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Duration perception in the range of seconds to minutes is an essential feature of cognition and behaviour; however, its precise underlying neural mechanisms are still unclear. Most accounts rely on the assumption that there is a mechanism directly mapping physical time into perceived time, i.e. a neural 'clock' or 'pacemaker' (Block & Zakay, 1996; Matell & Meck, 2004; Treisman, 1963; Treisman, Faulkner, Naish, & Brogan, 1990). Among these, the prominent pacemaker-accumulator model proposes that duration perception arises from a process wherein a pacemaker generates sequential neural pulses that are stored in an accumulator: according to this suggestion, the number of pulses accumulated over a certain interval constitutes the brain's estimation of the duration of that interval (Church, 1984; Treisman et al., 1990). A variation of this model proposed that perceived duration depends on the functioning of multiple neural oscillators, each with phasic activity operating on different timescales (Matell & Meck, 2004; Mauk & Buonomano, 2004; Treisman et al., 1990; van Rijn, Gu, & Meck, 2014).
Several studies have now linked levels of striatal dopamine to duration perception (Allman & Meck, 2012a; Coull, Cheng, & Meck, 2011; Coull, Hwang, Leyton, & Dagher, 2012; Matell & Meck, 2004; Meck, 2006; Soares, Atallah, & Paton, 2016). Specifically, increased dopaminergic activity has been related to overestimation of duration, and vice versa, for intervals in the region of one second (Coull et al., 2011; Terhune, Sullivan, & Simola, 2016). This has led several researchers to propose a fundamental role in time perception for neural oscillators that form a part of the ascending nigrostriatal dopamine pathway of the dorsal striatum (Coull et al., 2011; Matell & Meck, 2004; Meck, 2006; van Rijn et al., 2014). Taking advantage of the link between increased striatal dopamine and spontaneous blinking (Groman et al., 2014; Karson, 1988), Terhune and colleagues reported an apparent behavioural correlate of the influence of dopaminergic activity in human reports of duration. They presented evidence for transient variations in duration estimation in the sub- and supra-second range, with participants systematically biased towards reporting durations as longer immediately after spontaneous blinking, as compared to when no prior blink was present (Terhune et al., 2016). This finding was interpreted as a demonstration of dopaminergic influence on neural 'clock speed' or temporal attention, implying that the results provided evidence in favour of the existence of such a clock underlying duration perception (Terhune et al., 2016).
By contrast with neural clocks, a basis for human duration perception in broader physiological terms has a long history (Hoagland, 1933; Hoagland, 1935; Münsterberg, 1899; Pollack, Ochberg, & Meyer, 1965), and in recent years has again become popular (Craig, 2009a; Lernia et al., 2018; Meissner & Wittmann, 2011; Wittmann, Simmons, Aron, & Paulus, 2010). This broad physiological basis may be linked with the pacemaker-accumulator model by interpreting physiological processes as sources of pacemaker pulses (Lernia et al., 2018). Recent suggestions focus on the role of rhythmic interoceptive signals: in particular the heartbeat. Although researchers have long attempted to uncover a relationship between cardiac activity and duration perception, most attempts have been unsuccessful, or at best not easily interpreted (Bell & Provins, 1963; Ochberg, Pollack, & Meyer, 1964; Osato, Ogawa, & Takaoka, 1995; Schaefer & Gilliland, 1938; Schwarz, Winkler, & Sedlmeier, 2013; Surwillo, 1982). Only few studies have found suggestive changes in cardiac activity during the encoding of time intervals (Meissner & Wittmann, 2011; Pollatos, Yeldesbay, Pikovsky, & Rosenblum, 2014), though a major confounding factor in some of these studies is the association of autonomic activity with variations in arousal or attention that may have non-specific effects on time perception (as well as other cognitive) tasks (Bradley, 2009; Fernandes, Koji, Dixon, & Aquino, 2011; McConnell & Shore, 2011; Schwarz et al., 2013).
Alternative accounts for duration perception suggest that, rather than being (primarily) internally-driven by neural or physiological clocks or other rhythmic processes, the basis for duration perception lies in changes in perceptual content (Herbst, Javadi, Meer, & Busch, 2013; Kanai, Paffen, Hogendoorn, & Verstraten, 2011; Linares & Gorea, 2015; Ornstein, 1969). Under these accounts, measurable exteroceptive stimulus attributes, rather than bodily signals, should best correlate with duration estimates. This simple approach has often been dismissed because changes in internal states, such as arousal or attention, can lead to the exact same perceptual content (stimulus) being reported as different in duration (Block & Zakay, 1996; Brown, 1985; Polti, Martin, & van Wassenhove, 2018; van de Ven, van Rijswijk, & Roy, 2011; Zakay & Block, 2004). However, a recent development (Roseboom et al., 2019) of this simple idea suggests that it is not how much perceptual stimulation itself changes that is key, but rather how much change in neural activity occurs in perceptual classification networks, in response to perceptual stimulation, that provides a basis for duration perception. This distinction allows changes in stimulation to drive changes in neural activity (based on changes in perceptual content), but further, that this neural activity is constrained by the state of the perceptual system during estimation, allowing for fluctuations in, for example, attention to time (or other task-dependent features).
A computational model based on this proposal successfully predicts human duration estimations for a wide range of durations and types of perceptual content (Roseboom et al., 2019). Using an artificial perceptual classification network, the model produced duration estimates from input videos of natural scenes (1–64 seconds duration) based on frame-by-frame changes in network activation patterns in response to video content. Model-produced estimates were well-matched to human estimates made regarding the exact same scenes. Moreover, model estimates replicated qualitative biases in human reports by scene, with busy scenes (e.g., walking around a city) judged as longer in duration than less busy scenes (e.g., walking in the countryside or sitting in an office). Model performance was further improved when based on content from the area in the scene where human participants were looking (based on human gaze data), as opposed to the entire screen. That model estimates produced these qualitative biases provided strong evidence for a basis of human duration estimation in the dynamics of perceptual classification. Crucially, in achieving this outcome, the model made no use of autonomic or oscillatory neural processes.
Accompanying the behavioural reports of apparent duration by human participants, Roseboom et al (2019) recorded where in the scene participants were looking (using eye-tracking) and monitored their heartbeat (using blood-volume pulse measurements) throughout the experiment. In Roseboom et al., (2019), only the behavioural reports and computer modelling results were presented; results in the present study come from analyses conducted on the combination of behavioural reports, eye-movements (saccades, blinks, and pupil size), and heart rate data.
Unlike most studies on duration perception, which typically use simple stimuli (circles on a screen (Terhune et al., 2016), auditory tones (Meissner & Wittmann, 2011)), or in some cases specifically interoceptive stimuli (Lernia et al., 2018), the present study used complex, naturalistic visual scenes, closer to everyday phenomenological experience, in which complexly changing visual information is prominent. In combination with the eye-tracking and heartbeat data, this dataset allows investigation of the different proposed contributors to human duration estimation; in particular a contrast between external (stimulus change) and internal (potentially striatal dopaminergic activity and fluctuations in heart rate) components.
We hypothesized that time perception would arise from changes in perceptual content and therefore, under exposure to naturalistic visual stimulation, the influence of internal processes would be negligible. To investigate this proposal, we analysed the participants' data, partially presented in (Roseboom et al., 2019), to look for associations between duration estimates and external and internal events, specifically: i) visual content and saccades, ii) autonomic fluctuations and iii) dopaminergic phasic activity. The previously published analyses in Roseboom et al. (2019) presented only participants' duration estimates and no other physiological or eye behaviour data.
First, we looked at the relationship between visual content and duration estimation. An association between visual content (scene type: city, campus and outside, and office or café) and duration estimation has previously been reported for this data, with scenes with greater perceptual change driving longer estimates (Roseboom et al., 2019). This result is in agreement with the proposal that time perception is related to changes in perceptual content.
However, this association could instead arise from a potential relationship between visual content and eye movements – specifically saccade density, defined as the number of saccades per second. Previous evidence indicates that stimulus-driven factors (Itti, 2005; Mital, Smith, Hill, & Henderson, 2011) influence eye movements, with results often consistent with minimising sensory prediction error (Friston, Adams, Perrinet, & Breakspear, 2012; Gottlieb, Oudeyer, Lopes, & Baranes, 2013; Itti & Baldi, 2009; Tatler, Hayhoe, Land, & Ballard, 2011). In the context of a dynamic video, sensory prediction error might be, naïvely, expected to correlate with perceptual change between one time point and the next. A simple hypothesis might then be that saccade density would be greater for videos with greater perceptual change, showing a similar dependency of subjective duration as shown for visual content. This pattern of results would imply that an account of subjective time perception based on changes in perceptual content could instead be based on something far more trivial: tracking stimulus-driven eye movements. Aiming to rule out such trivial alternative interpretations, we analysed the threefold relationship between visual content, saccade density and duration estimates.
As mentioned, it has long been suggested that repetitive physiological signals may form the basis for human time perception. Craig (Craig, 2009a) postulated a key role for the accumulation of interoceptive visceral information in the anterior insula, which has been related to integration of autonomic signals and interoceptive awareness (Craig, 2009b; Nguyen, Breakspear, Hu, & Guo, 2016). An fMRI study by Wittmann and colleagues (Wittmann et al., 2010) identified a pattern of accumulating neural activity in the bilateral posterior insula during the encoding of time intervals in the range of seconds. The authors suggested that this accumulation corresponded to a clock-type (pacemaker) pattern, recording sequential physiological states during the attended interval (Wittmann et al., 2010). Another study (Meissner & Wittmann, 2011) examined the evolution of cardiac activity throughout the encoding of time intervals and found a progressive increase in cardiac periods (slowing down of heart rate). Furthermore, in this study, individuals' duration reproduction accuracy correlated positively both with the slope of cardiac slowing during encoding and with interoceptive accuracy, measured in a heartbeat counting task. The authors reasoned that such heart rate slowing could correspond an accumulation of parasympathetic activity, consistent with the proposed insular pacemaker.
In light of these claims, we looked for similar associations between cardiac activity and duration estimation or accuracy in our own data by assessing both average heart rate and progression of heart rate during video presentation. As an additional marker of autonomic activity, we also examined pupil size (Bradley, Miccoli, Escrig, & Lang, 2008; Laeng, Sirois, & Gredeback, 2012; McDougal & Gamlin, 2015) – presented in the Supplementary Materials. Information on interoceptive accuracy or awareness was not collected in our experiment.
Finally, we examined evidence for the proposed association between striatal dopaminergic activity and duration estimation (Coull et al., 2011; Matell & Meck, 2004; Mauk & Buonomano, 2004), following Terhune and colleagues' approach (Terhune et al., 2016) of employing spontaneous blinking as a proxy for transient fluctuations in striatal dopamine (Groman et al., 2014; Karson, 1988). Terhune and colleagues claimed that subjective duration reports in both the sub- and supra-second range (300–2600 milliseconds) were longer when the participant had blinked immediately before the trial (Terhune et al., 2016). In their experiment they employed simple auditory (white noise bursts) and visual stimuli (circles on a screen). We therefore decided to investigate whether the same association (particularly for the shorter videos, 1–3 seconds) was present while viewing dynamic, naturalistic visual stimuli.
The methods concerning data collection are as reported in (Roseboom et al., 2019); data analysis techniques are specific to the present study. Human participants watched a series of silent videos containing natural scenes with different amounts of 'liveliness' – which translated to different amounts of perceptual change. Their task was to report the estimated duration of each presented video. Eye-tracking recorded participants' pupil size, gaze fixation, saccades and blinks. Blood-volume pulse recordings allowed us to measure cardiac activity.
Fifty-five human participants (40 female, average age 21.4) took part in the experiment. All were recruited from the University of Sussex, over 18 and reported normal or corrected-to-normal vision. They provided informed consent and were awarded with course credits or, alternatively, £5 per hour for their participation. The study was granted ethical approval by the Research Ethics Committee of the University of Sussex.
Three (female) participants were excluded from the analysis because eye-tracking was not successfully recorded or substantially missing. After exclusion of those subjects, the remaining dataset totalled 4060 trials.
Stimuli were based on videos obtained in the city of Brighton (United Kingdom), the University of Sussex campus, and the local countryside. These videos were recorded with a GoPro Hero 4 camera at 60 Hz and 1920 × 1080 pixels, and further processed at 30 Hz and 1280 × 720 pixels. The brightness of the videos was not controlled. The stimulus employed in each experimental trial was extracted from a pseudo-random list of 4290 video fragments, comprising 330 repetitions of each of 13 durations ranging from 1 to 64 seconds (1, 1.5, 2, 3, 4, 6, 8, 12, 16, 24, 32, 48, 64 s).
The videos could be classified into three video types in terms of content: videos recorded while walking around the city, scenes recorded while walking around the campus and outside in the campus green zones, and quiet scenes in an office or café. Each video type has a greater amount of perceptual change than the next. Perceptual change can broadly be defined as the amount of change between consecutive video frames – more complex and dynamic videos will have greater perceptual change than static scenes involving inanimate objects. Although used only qualitatively in the present paper, the construct validity of 'perceptual change' for these stimuli was previously confirmed (Roseboom et al., 2019) by feeding the same videos into an image classification algorithm and quantifying the frame-by-frame rate of change at different hierarchical levels of visual information: from pixel-wise to object-level changes. Within each layer of the image classification network, frame-by-frame change was calculated as the Euclidean distance between the neural activation pattern for one video frame and the next; whenever it exceeded a dynamic 'saliency' threshold, perceptual change was deemed to have occurred and one 'change unit' was accumulated over time. For all video durations the network determined that perceptual change, thus computed, was greater for city videos, intermediate for campus and outside scenes, and lower for office and café (Roseboom et al., 2019). Specifically, duration estimates produced by the network (which were a transformation of the accumulated perceptual change, converted from arbitrary 'change units' into seconds by support vector regression) deviated from the mean by +24%, –4% and –7% for city, campus/outside and office/café videos, respectively.
Experiments were programmed in MATLAB 2012b (MathWorks Inc., Natick, US-MA), employing Psychtoolbox 3 and the Eyelink Toolbox, and presented on a LaCie Electron 22 BLUE II 22" with screen resolution of 1280 × 1024 pixels and refresh rate of 60 Hz. Eye tracking was performed with Eyelink 1000 Plus (SR Research, Mississauga, Ontario, Canada) at 1000 Hz sampling rate, using a desktop camera mount and a chin and forehead rest to stabilize head position at 57 cm from the screen. Calibration of the eye-tracking system was performed at the beginning of each 20-trial block, with a standard 5-point grid and a maximal average error of 0.5 degrees of visual angle (dva). The thresholds for saccade detection were: 0.15 dva motion, 22 dva/s speed, 4000 dva/s2 acceleration. Blood-volume pulse (BVP) measurements were obtained using a BVP-Flex/Pro (9308M) sensor and FlexComp System (T7550M) from Thought Technology (Montreal, Quebec, Canada). Heartbeats were detected by applying a peak detection algorithm on the BVP data.
The experimental session lasted for one hour and typically comprised 80 trials completed in four 20-trial blocks. As detailed in (Roseboom et al., 2019), for logistical reasons some participants did not complete all 80 trials. The specific trials assigned to each participant were randomized, and neither their content nor duration was balanced or constant across participants. However, all subjects watched at least one video of each of the 13 video durations – except one subject who lacked trials with three durations. The raw trial-by-trial data for each participant is available in the Supplementary Material. The task required a report of the estimated duration of each video in seconds, performed immediately after the video ending by using a visual analogue scale.
Statistical analysis was conducted on Matlab 2016a (MathWorks Inc., Natick, US-MA), R 3.4.4 (The R Foundation for Statistical Computing, http://www.R-project.org) and JASP 0.8.5.1 (JASP Team 2017).
In our analyses we separately employed two dependent variables related to duration estimation: responses and error sizes. 'Response' was the estimate of duration (in seconds) provided by the participant in a given trial and was analysed for potential under or overestimation of time intervals in different conditions. 'Error size' represented the amount of deviation of responses from veridical magnitude, regardless of direction; it was calculated as the absolute value of the relative error, i.e. error size = |response-duration|/duration. Both measures, but critically error size (inaccuracy), depend not only of time perception but also more broadly on general processes involved in cognitive tasks (Livesey, Wall, & Smith, 2007). In our analyses, we systematically tested the potential association between different external and internal factors (scene type, saccades, pupil size, blinking, cardiac activity) with these two dependent variables, as discussed in the Introduction – see 'General Aim and Rationale of Analyses'.
All tested factors were measured trial-wise. Saccade density and average heart rate were computed over video presentation. Heart rate progression through video presentation was calculated as described by Meissner and Wittmann in (Meissner & Wittmann, 2011): cardiac (inter-peak) periods were resampled at 5 Hz using cubic interpolation, averaged on a second-by-second basis and normalized per participant. The slope (linear regression coefficient) of the time series of cardiac period progression indicated the progression of heart rate throughout each trial's video presentation: a positive slope implies that heart rate progressively slowed down (inter-peak periods increasing with seconds since video onset) and vice versa.
Pre-trial blinking was assessed for the 2000 ms immediately preceding trial onset. In separate analyses, only the period between 2000 ms and 1000 ms prior to trial onset was considered. The purpose of the second analysis, following Terhune and colleagues (see 'Supplemental Experimental Procedures' in (Terhune et al., 2016)), was to prevent confounding effects by saccades elicited by blinks around stimulus onset, as saccades are known to affect time perception (Grossman, Gueta, Pesin, Malach, & Landau, 2019; Yarrow, Haggard, Heal, Brown, & Rothwell, 2001). We considered that a blink was present when the 'onset' of a blink was identified in the eye-tracking recording within the period of interest. Thus, we defined two binary variables based on the occurrence (or lack) of a blink within those two time ranges: 2000 ms to trial onset and 2000 – 1000 ms before trial onset. For brevity we will refer to these binary variables as B2000 and B1000, respectively.
Both dependent and quantitative independent variables were normalized within participant and video duration to make them independent of both these factors. Thus, normalized responses represent trial-by-trial variability of the estimates provided by the same participant for that specific duration. The other normalized variables are interpreted in an analogous manner.
Associations between (normalized) internal and external factors and duration estimation and accuracy were explored both for all video durations pooled and for each duration separately, considering that duration perception might depend on different mechanisms for shorter (~1 s) and longer (~1 min) intervals (Wiener, Turkeltaub, & Coslett, 2010). Results for individual video durations are presented in section S3 of the Supplementary Materials.
For Bayesian statistical analyses we employed the default JASP priors: for t-tests, a prior distribution Cauchy (0, √1/2); for Pearson correlations, a uniform distribution U(–1,1); for ANOVAs and repeated-measures ANOVAs, r scale prior width of 0.5 for fixed effects and 1 for random effects. The wording employed for describing the amount of evidence indicated by the Bayes factor corresponds to that suggested by Lee and Wagenmakers (Lee & Wagenmakers, 2013). We consider that evidence in favour of the alternative hypothesis is more than anecdotal when BF10 > 3; conversely, there is more than anecdotal evidence in favour of the null when BF10 < 1/3 (equivalently BF01 > 3).
The main analyses were concerned with independent hypothesis testing for the potential effect of each considered factor on duration perception. However, in the Supplementary Materials we report the effect size of each factor by means of Bayesian multilevel regression. See section S1 of the Supplementary Materials.
Figure 1a depicts participants' responses per video duration. As expected, veridical duration is strongly associated with subjective duration estimates, albeit showing an apparent effect of regression to the mean in responses (often referred to in the temporal domain as Vierordt's law) as suggested by a slope of less than one between veridical and estimated durations.
As reported in (Roseboom et al., 2019), videos with greater perceptual change were estimated as longer in duration, such that, in terms of scene type, duration reports followed the order: city > campus/outside > office/café. Specifically, in terms of z-scores (normalized reports within participant and video duration), average responses for video type were city z = 0.14, campus/outside z = 0.036, office/café z = –0.091. We ran a Bayesian ANOVA on the effect of scene type on duration estimates and found extreme evidence in favour of such effect, with a Bayes factor BF10 = 8.561 * 106. Figure 1b depicts the average and 95% credible intervals of the normalized responses per scene type. Examining all pairwise comparisons between scene types, we found only anecdotal evidence for a difference in responses between city scenes and campus/outside (BF10 = 1.378), but at least very strong evidence for a difference between the other pairs: BF10 = 3.621 * 107 for city versus office/café, BF10 = 34.789 for campus/outside versus office/café.
We ran a Bayesian ANOVA to test for differences in (normalized) average saccade density by video type (urban, campus/outside, office/café), obtaining extreme evidence for difference between all three types (BF10 > 100). However, the association between saccade density and perceptual change was not straightforward, as average saccade density was highest for city scenes (z = 0.218), smallest in campus/outside scenes (z = –0.216), and intermediate for office/café scenes (z = 0.012) (Figure 2b).
These results rule out trivial interpretations of the interaction of perceptual change and duration estimation in terms of differences in saccade density. Specifically, the relationship between perceptual change and duration estimation cannot be explained simply by tracking stimulus-driven eye movements, because saccade density is non-monotonically related to duration estimation (compare Figures 1B and 2B). This interpretation is in line with the modelling results reported in Roseboom and colleagues' study (Roseboom et al., 2019).
We performed a Bayesian bivariate correlation between trial-by-trial normalized saccade density and response – see scatter plot in Figure 2D. Pearson's coefficient and 95% credible intervals were r = 0.042 (0.011 – 0.073), suggesting a weak positive correlation; the Bayes factor was insensitive, anecdotally in the direction of the null hypothesis: BF10 = 0.621. Thus, there was no support for either the existence or absence of a correlation between saccade density and duration estimates, when considering the entire sample – a result consistent with the non-monotonic relationship between saccade density and video type reported above.
We further assessed whether an association between saccade density and responses could be present only for certain video durations and split the dataset according to the latter variable. We ran a Bayesian correlation between normalized saccade density and response for each of the 13 resulting datasets. Only for the longest duration (64 seconds) did we find evidence for an effect of saccade density on response (r = 0.190, BF10 = 16.879) – a positive correlation – though the meaning of this isolated finding is unclear. Scatterplots for all separate durations are presented in the Supplementary Materials, section S3.
Since the scatterplots for the performed correlations are difficult to interpret visually, we also provide a plot (Figure 2C) showing the pattern of descriptive results for the relationship between trial-by-trial saccade density and duration estimates. The error bars represent normalized responses per video duration, split into trials with below and above-average saccade density, compared with other trials from the same participant and with the same duration. No overall pattern is observed that in any way suggests a different distribution of reports for trials with different saccade density. Note that the dichotomization of saccade density has been adopted for graphical purposes only and all statistical analyses employ saccade density in its continuous, non-dichotomized form.
In summary, our data suggests a relationship between perceptual change and duration estimates, as well as (less straightforwardly) between perceptual change and saccade density. However, there is no clear global effect of saccade density on duration estimates.
In a Bayesian bivariate correlation between normalized saccade density and error size (Figure 2F), Pearson's correlation coefficient and 95% credible intervals were r = –0.061 (–0.093, –0.030), with the Bayes factor indicating strong evidence in favour of the existence of a correlation: BF10 = 29.07. The negative sign of the correlation indicates that participants were more accurate (made smaller errors) in trials where their saccade density was greater. Considering that saccade density was not directly associated with duration estimates, it seems likely that its correlation with accuracy does not necessarily imply a link between saccades and the neural basis of time perception. Instead, it could indicate an unspecified effect on task performance – perhaps as an index of the level of attention or engagement with a visual task.
The trial-wise relationships between both mean heart rate and response, and mean heart rate and error size were assessed by two Bayesian bivariate correlations. In both cases we found very strong evidence against the existence of a correlation. Concerning response (Figure 3B), the Pearson's correlation coefficient and 95% credible intervals were r = 0.008 (–0.025, 0.042), with a Bayes factor BF10 = 0.024. Results for accuracy (Figure 3D) were r = –0.013 (–0.047, 0.020), BF10 = 0.029. This absence of any clear overall relationship between mean heart rate and either response or error size is evident in Figures 3A and 3C, which depict aggregated responses (3A) and error sizes (3C), split by average heart rate. Scatterplots for each separate video duration are supplied in the Supplementary Materials.
After obtaining normalized second-by-second cardiac periods for each trial, as described in the Methods section, we split the dataset into 11 video durations – only considering durations over 2 seconds in order to allow second-by-second cardiac progression to be calculated. We tested whether there was any effect of time since video onset on cardiac periods by Bayesian repeated-measures ANOVA, run separately for each video duration. The dependent variable was the average normalized cardiac period measured at each second since video onset. The only within-participant factor was time (in seconds) since video onset. Thus, the ANOVA had as many levels as seconds of video duration.
Evidence for an effect of time from onset on second-by-second cardiac periods was at least moderate (BF10 > 3) for videos of 4s, 8s, 12s and 48s, with BF10 = 23, 95589, 230 and 11, respectively. Conversely, there was also at least moderate evidence for the null (no different cardiac periods at different time points, with BF10 < 1/3) for 2s, 3s, 6s, 16s, 32s and 64s. Figure 4 presents the average cardiac periods and 95% credible intervals at each time point (seconds since onset) for six different video durations. The ascending slope indicates that the effect of time (when it exists) involves a slowing-down of heart rate throughout the presentation of the video (i.e. increasing cardiac periods), consistent with the results reported by Meissner and Wittmann during the 'encoding phase' of time intervals of 8, 14 and 20 seconds (Meissner & Wittmann, 2011). As shown in lower panels of Figure 4, the deceleration of cardiac periods reaches a plateau after the first 5–10 seconds; this stabilization might be the reason why weak or no evidence in favour of the alternative hypothesis is found for the longest video durations.
Our finding of a reduction in heart rate throughout video presentation is in agreement with the results reported by Meissner and Wittmann (Meissner & Wittmann, 2011), who additionally found a positive correlation between heart rate reduction and accuracy in reproduction of the presented interval. This reduction was explained in terms of a hypothetical pacemaker-type accumulating mechanism related to an increase in parasympathetic activity that would track duration perception. We sought to test this hypothesis in our own data by analysing the relationship between cardiac period slope (linear slope for the second-by-second progression in cardiac periods throughout the trial) and duration estimation (response) and accuracy (error size). In a Bayesian bivariate correlation between cardiac period slope and response we obtained a Pearson's r = –0.030 with 95% credible intervals (–0.066, 0.005), and a Bayes factor BF10 = 0.094, indicating strong evidence against the existence of a correlation (Figures 5A–5B).
We approached the relationship between heart rate progression and accuracy in two ways: First, by analysing trial-wise associations within each participant, and second, following Meissner and Wittmann (Meissner & Wittmann, 2011), by looking for differences in participant's average cardiac period slope between good and poor duration estimators.
Bayesian correlation between trial-wise cardiac period slope and error size yielded Pearson's r = 0.005 (–0.030, 0.040), with Bayes factor (BF10 = 0.023) indicating very strong evidence against any effect of cardiac period slope on accuracy on the overall dataset (Figures 5C–5D). Similar results were obtained when assessing trials of each video duration separately: the Bayes factor indicated at least moderate evidence against the existence of a correlation (BF10 < 1/3) for all video durations, with the exception of 2-second videos, where evidence for the null was anecdotal (BF10 = 0.693, with a Pearson's coefficient of –0.277 (–0.548, 0.073)). See Supplementary Materials, section S3, for further detail.
Although we failed to find an association between heart rate progression and accuracy in duration estimation on a trial-by-trial basis, we enquired whether this association could be present at the participant, rather than the trial level. We classified participants into good or poor performers, depending on whether their average error size was below or above the sample median. We analysed the effect of time since video onset on cardiac period progression in good and poor performers, considering each participant's time-series of average second-by-second cardiac periods for all 11 video durations over 2 seconds, taken separately. We performed a Bayesian repeated-measures ANOVA for each duration – Figures 5E–5H show four of them (8, 12, 16 and 24s – the periods most similar to those used in Meissner & Wittmann, 2011). The dependent variable was the average cardiac period at each time point (seconds since video onset). We employed time since onset as the only within-participant factor (with as many levels as seconds of video duration) and the binary classification on performance (good or poor) as between-participant factor. If there was any difference in cardiac period progression between good and poor performers, we should find evidence for the inclusion of the interaction term (time since onset * performance) in the model.
In all analyses, the best model was either the one containing only time from onset, or the null model. This indicated that in some cases (specifically for 4, 8, 12 and 48 seconds) there was an effect of time since video onset on second-by-second cardiac periods, while in the remaining cases there was no evidence for a time-related difference. In any case, neither the cardiac periods at each time point (main effect) nor their progression throughout the trial (interaction with time) were different between good and poor performers. The Bayes Factor for inclusion of the interaction term (the one relevant to our question) was always at least moderately against its inclusion (BFinclusion < 1/3), except for duration of 3 seconds (BFInclusion = 0.367). Furthermore, it was extremely against inclusion (BFinclusion < 1/100) in all cases except for 2–4 and 8 seconds. Thus, evidence consistently opposed any supposed difference in cardiac period progression during video presentation in good versus poor performers in a duration estimation task.
In Supplementary Materials (S2) we explore the association between another autonomic marker, pupil size, and duration estimation. As with cardiac activity, we find no association with either the magnitude or the accuracy of duration estimates.
Trials were dichotomized according to the presence or absence of blinking in the 2000 ms leading to video onset (B2000), or in the pretrial period 2000–1000 ms (B1000). Considering that for long video durations pre-trial blinking may not be an accurate index of dopaminergic activity throughout the entire interval, we restricted the analyses to durations up to 3 seconds – comprising 1248 trials in total. Responses for those durations, split according to presence or absence of a pre-trial blink, are presented in Figure 6. We ran a Bayesian one-way ANOVA on short-video trials (1–3 s duration), with normalized response as dependent variable and B2000 as fixed factor. We repeated the same analysis using B1000 as fixed factor instead. The Bayes factor indicated strong evidence against the effect of B2000 on duration estimates (BF10 = 0.068), and moderate evidence against B1000 (BF10 = 0.150).
This study aimed to shed light on the mechanisms of human duration perception by assessing the contribution of internal physiological and neural signals to the biases in human duration estimates for naturalistic videos. As previously reported (Roseboom et al., 2019), human participants' estimates were longer for more dynamic videos, such as city scenes, than for less dynamic videos of a quiet office. That study presented a model of human duration perception that could reproduce these human biases by computing perceived video duration on the basis of frame-by-frame perceptual change, without appealing to previously hypothesised pacemaker processes. In the present analyses, we could not find any evidence to support the potential influence of hypothesised pacemakers on our participants' duration reports – whether driven by autonomic processes (revealed by cardiac activity and pupil size) or by dopaminergic phasic activity (indexed by spontaneous blinking).
First, our analyses ruled out trivial interpretations for the previously reported association between perceptual change and duration estimation, namely the possibility that time perception was produced by tracking saccadic movements. We found that there was evidence for some relationship between saccadic density and stimulus change in that longer video durations were associated with lower average density – likely reflecting a decrease in saccade frequency as a video progresses, possibly due to waning in novelty. However, average saccade density was greater for office/café scenes (with lowest amount of perceptual change, as computed in Roseboom et al., 2019) than for campus/outside videos, making any naïve novelty-based interpretation less than straightforward. Whatever the reason for the obtained pattern of results, the relationship between perceptual change and saccade density does not follow the same pattern as with duration estimates. In light of this, the observed association between saccade density and greater accuracy in duration estimation (but not estimated duration magnitude, according to the Bayes factor for the correlation) likely reflects greater general engagement, highlighting the caveat that associations between physiological signals and accuracy may indicate a non-specific attentional effect on cognitive performance, without any specific relation to the mechanism(s) of duration estimation.
Consistent with previous findings (Meissner & Wittmann, 2011) we found evidence for an initial change in cardiac rate at the beginning of a new video presentation, consisting of a progressive cardiac deceleration during the first 5–10 seconds of video presentation, compatible with parasympathetic activation (Bradley et al., 2008; Laeng et al., 2012). Cardiac deceleration (reportedly lasting up to the end of the presented intervals, ranging from 8 to 20 seconds) has been described as an indication of an accumulating pattern of autonomic activity working as a clock-type system, consistent with an interoception-based pacemaker-accumulator model (Meissner & Wittmann, 2011); in that study, cardiac deceleration was more pronounced in good performers (i.e., participants showing greater accuracy in duration reproduction). In our case, heart rate deceleration happened only at the beginning of video presentation, although for short videos this could comprise most or all of their duration, stabilizing thereafter: we therefore suppose that it reflects an initial arousal response in relation with a new video/task (Bradley, 2009), rather than a process specifically related to time perception. All of our analyses failed to reveal any statistical association between cardiac activity (heart rate or heart rate progression) and duration estimation or accuracy, with the vast majority indicating evidence for the null hypothesis.
Interestingly, when examining putative group differences in cardiac period progression in good versus poor performers, we found no difference in overall progression in both groups (contrary to findings in (Meissner & Wittmann, 2011)), but, on visual inspection, a more pronounced ascending slope was observed in good performers, only for the first 3–5 seconds of the video, in several video durations: see Figures 5E, 5G and 5H. This might indicate a more pronounced arousal response in good performers, related to greater engagement at the beginning of the video presentation, but the fact that the putative difference only affects the very early seconds of the presentation, and does not extend up to the end of the video, does not fit with the proposal of an accumulating pacemaker-type role involving cardiac period.
Regarding the purported association between striatal dopamine and duration perception, our results based on pre-trial blinking, following Terhune and colleagues' analyses (Terhune et al., 2016), were not consistent with the conclusions reported in their study. Nevertheless, several differences in the experiments must be considered. First, regarding the stimuli, our experiment used videos of natural scenes over a broad range of durations, while Terhune and colleagues (Terhune et al., 2016) used basic auditory noise bursts or visual flashes. Another difference was task. Our experiment required participants to directly estimate the observed duration in seconds. Terhune and colleagues (Terhune et al., 2016) used a temporal bisection task wherein participants reported whether the observed duration was closer to long or short anchor durations on which they had been trained. While a large literature has linked striatal dopamine to duration estimation and time perception generally (Allman & Meck, 2012b; Coull et al., 2011; Gu, Jurkowski, Lake, Malapani, & Meck, 2015; Jones, Malone, Dirnberger, Edwards, & Jahanshahi, 2008; Matell & Meck, 2004; Mauk & Buonomano, 2004; Rammsayer, 1999; Wiener, Lee, Lohoff, & Coslett, 2014), it is also well known that striatal dopamine is critically involved in the biasing of decisions in many other dimensions, especially for goal-directed or reward-driven decisions (Friston et al., 2014; Howard, Li, Geddes, & Jin, 2017; Lepora & Gurney, 2012; Lo & Wang, 2006; Nagano-Saito et al., 2012; Sarno, de Lafuente, Romo, & Parga, 2017) – see (Balci, 2014) for an overview of some of these issues as they relate to the time domain. Considering this, the absence of evidence for an effect of pre-trial blinks in our data may not reflect a failure to replicate the previously reported influence of spontaneous blinks on time perception. Instead, it may indicate that our direct duration estimation task is not susceptible to the kind of bias in report that is susceptible to dopaminergic influence: i.e. a shift in decision criterion in a bisection task (Soares et al., 2016; Terhune et al., 2016) or peak-interval procedure. The latter has been commonly used in the rodent literature (Balci, 2014), and presented as evidence of the influence of changes in striatal dopamine on time perception specifically, rather than reflecting uncertainty (Lak, Nomoto, Keramati, Sakagami, & Kepecs, 2017) and biases in decision making (Wang, Rangarajan, Gerfen, & Krauzlis, 2018) more generally. Our results support that further direct replication of the study by Terhune and colleagues (Terhune et al., 2016) with extension to other tasks is required.
Our study, as most studies referenced in this paper (e.g. (Meissner & Wittmann, 2011; Terhune et al., 2016)), involved prospective time judgments, wherein participants know they must estimate duration of an interval in advance of the interval presentation, and therefore direct their attention to ongoing time itself (Block & Gruber, 2014). By contrast, retrospective timing tasks require participants to be naïve to the fact that they will be asked about time until after the interval presentation (Block, Hancock, & Zakay, 2010). Differences in duration estimation under these different paradigms have led to proposals that estimation in different tasks must be, at least partially, underpinned by different processes (Block, 1982; Block et al., 2010; Block & Reed, 1978; Zakay & Block, 1995). As we only tested participants' duration judgements under a prospective paradigm, for now, we can only make conclusions regarding the putative processes related to tasks in that context. Further investigation is required to broadly understand and reconcile the common and different components of prospective and retrospective timing processes.
Several caveats may be considered regarding our study. As mentioned, our experiment contains several differences from previous studies claiming a role for autonomic or neural processes, including the stimuli – naturalistic scenes instead of simple, auditory visual (Meissner & Wittmann, 2011; Terhune et al., 2016) or interoceptive stimuli (Lernia et al., 2018) – and task, using prospective magnitude estimation instead of reproduction, bisection, etc. Participants were asked to watch and 'engage' with the video content, knowing that they would be asked to report its duration in the end: thus, the specific deployment of 'attention to time' would have played some role, relative to some other paradigms. Additionally, the use of pre-trial blinking as a marker of striatal dopamine may be problematic as it is possible that the recorded blinks were not all truly spontaneous – our experiment was not explicitly designed to capture this. Blinks in our task may sometimes have been due to eye fatigue due to the long durations of trials and dynamic visual nature of the trials, or any number of other factors that were not controlled for (though a similar criticism is also largely available for the original study as the precise definition of 'spontaneous' is not clear). However, the complete lack of any statistical association between pre-trial blink and duration estimation suggests that any such modulation had very little effect in the naturalistic conditions of our experiment.
In summary, our results (together with results reported in (Roseboom et al., 2019) for the basic behavioural dataset) strongly support the hypothesis that human subjective time perception (on the scale of seconds) can be characterised primarily as driven by perceptual change. This is not to say that humans never make use of interoceptive information when judging duration, nor that humans rely entirely on vision for temporal perception. Such positions would be unsustainable. Rather, our data show that when provided with dynamic, naturalistic visual input, in the absence of other meaningfully changing input (the videos were silent and participants were seated and stationary), changes in visual content are related to human time estimation while changes in the other measured (cardiac cycle) and implied (striatal dopamine in relation to eye-blinks) factors were not. It is possible that in conditions other than naturalistic wakeful experience (such as simplified laboratory conditions, resting state with closed eyes, exteroceptive sensory deprivation) interoceptive information plays a larger part in multi-modal perceptual content. Nevertheless, under circumstances where humans observe naturalistic video stimuli, there is no evidence for a meaningful contribution of proposed autonomic or neural pacemaker processes to duration estimation.
All the behavioural, eye-tracking data and blood-volume pulse recordings as well as Supplemental Materials can be found on the study's project page at https://osf.io/re8jv/.
The additional file for this article can be found as follows:Text S1
Supplemental material. DOI: https://doi.org/10.1525/collabra.234.s1
The authors are grateful to the Dr Mortimer and Theresa Sackler Foundation, which supports the Sackler Centre for Consciousness Science. This project was supported by the European Union Future and Emerging Technologies grant (GA:641100) TIMESTORM – Mind and Time: Investigation of the Temporal Traits of Human-Machine Convergence, and AKS is grateful to the Canadian Institute for Advanced Research (CIFAR) programme on Brain, Mind, and Consciousness. Thanks to Michaela Klimova, Francesca Simonelli and Virginia Mahieu for assistance with the experiment and data collection.
The authors have no competing interests to declare.
M.S.P., K.N., Z.F. and W.R. contributed to the conception and design of the study; W.R. contributed to data acquisition; M.S.P. performed data analysis and interpretation; all authors contributing to drafting and revising the article. All authors have approved the final version to be submitted for publication.
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Zakay, D., & Block, R. A. (2004). Prospective and retrospective duration judgments: an executive-control perspective. Acta Neurobiol Exp (Wars), 64(3), 319–328.


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No charges will be filed in the suicide of David Molak, Bexar County District Attorney says
Molak's family said he was the target of cyberbullies in Alamo Heights.
SAN ANTONIO — The Bexar County District Attorney said Wednesday that no criminal charges related to the suicide of Alamo Heights teen David Molak will be filed, citing "insufficient evidence."
The decision came after a months-long investigation into the death of Molak, a 16-year-old who was found dead in his backyard in January. The Bexar County Medical Examiner ruled his death a suicide.
Bexar County District Attorney Nico LaHood said in an interview that the San Antonio Police Department submitted the findings of its investigation to the DA on Feb. 17 as a case of harassment.
"If we're not talking about physical bullying, we're really talking about harassment, and that is a vague statute," LaHood said. "Under the harassment statute, we have to have the evidence to back up the different elements of the allegation, and it's just not there."
MORE: SAPD investigating harassment claims in David Molak's suicide in Alamo Heights
Molak's family and friends said his death was the result of months of bullying that began while he was a student at Alamo Heights High School, and continued online after he transferred schools in November 2015.
Rumors on social media initially pinned a 15-year-old Alamo Heights High School freshman as the ringleader of the cyberbullies who targeted Molak. However, the student was not named publicly by police and authorities would not officially confirm any rumors.
The rumored cyberbully had posted a picture of himself on the photo-sharing app Instagram posing with Molak's girlfriend in October. The caption tagged Molak and said the boy was going to "steal your girl." It sparked reactions from scores of other students, including Molak that grew increasingly heated.
RELATED: Exclusive: Fellow students threatened violence, insulted David Molak online before his suicide
"Molak's an ape," one Alamo Heights student commented. "The monkey looking human gets his woman stolen."
"Put um inna coffin," one teen said while another mimicked with "Put em 6 feet under."
LaHood said that he "can't stand" bullying, and believes that a solution lies in a multifaceted approach that includes parents and schools.
"When you're talking about cyberbullying, you're talking about just a constant, repeated attack on someone's mind that is very damaging," LaHood said.
Even so, he said in this case his office had to stay focused on the facts and the law, which were not sufficient to warrant criminal charges.
EARLY COVERAGE: Alamo Heights student was a victim of bullying before committing suicide, family says
The Molak family released a statement criticizing a lack of legislation specifically against cyberbullying.
"Unfortunately, it's clear there were roadblocks that inhibited their investigation that we hope to address through legislation," the statement said. "The laws regarding this new type of social media harassment simply have not kept up with the times."
Although extremely disappointed, it has only made our family more determined to pursue David's Law that will ensure cyber bullying is a punishable offense in order to hold perpetrators accountable for their actions."
State Sen. Jose Menendez, D-San Antonio, announced his plans to file a bill that would establish "David's Law" weeks after Molak's death.
"I will work with families, school administrators, law enforcement, and others to ensure our schools have the tools they need to keep our students safe and protected from cyberbullying. No student should be afraid to attend class because they were harassed online," Menéndez said in an email announcing his plans.
LaHood said such a law could open doors for investigators in future case of cyberbullying.
"It will give us more avenues from an investigative standpoint on getting more information and evidence," he said.
Since Molak's death signs have been placed in yard throughout Alamo Heights and surrounding communities that read: "#DavidsLegacy, STOP BULLYING NOW, Stand up, Speak out."
Twitter: @MDWilsonSA

subset: commoncrawl


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Strengthen Your Online Presence
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A health lifestyle is definitely a fast growing trend and there are many businesses out to make their mark on the health and wellness industry. Creative Click Media can help your business stand out in the crowd.
I am forever grateful to you for taking the time to help me with my website! You came very highly recommended to me and you did not disappoint. As a matter of fact you went above and beyond. I would highly recommend that if anyone is looking for a web designer with integrity and who really cares, go with Creative Click Media!! Thank you so much again!!!


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The Moss (S)
Welcome to The Moss! Completely handmade, this books features 140 blank pages of 80 lb paper hand stitched with 4 - ply waxed linen thread in natural white. The straight edge is secured closed by a silver button pin. This is a great, secure closure option for a minimalist look and ease of use. The natural green leather won't scratch easily and will age well holding it sheen and color. Scroll down for additional photos!
Dimensions: 6.5 X 4.75 inches (size small)


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A few days ago, I shared the new arrangement in our family room as well as the progress on Calvin's room. I said I would give all of the details on the new pieces of furniture and this post is making good on that promise! Now, I admit, furniture stores have never been my thing. Give me a flea market, … Read More
The trials of decorating for an 8-year-old boy
Decorating for kids is hard. I'm learning that as I'm working with my eight-year-old on transforming the guest room into his room. We have conversations about it that go something like this… "So, let's talk about your room, bud, and how you would like it to look." "Okay." "What colors would you like?" "Ummm… Red, green, black, gray, orange, blue. … Read More
styling the girl's vintage bedroom
When I was a little kid, my favorite toy was my dollhouse. I enjoyed living out the imaginary lives of the little people who resided there, but my favorite part was arranging and rearranging the furniture. Even building "additions" with metal lebkuchen tins to make room for more furniture. I carried that into my teen years when I rearranged and … Read More
Pine Cone Hill Giveaway
When I revealed my parent's bedroom makeover a couple of weeks ago, I shared that I would be hosting a giveaway for some Pine Cone Hill bedding and here it is! Pine Cone Hill furnished the bedding for this room makeover and offered to give away one Boyfriend Matelasse Coverlet in the color and size of your choosing to one … Read More
kim's coastal bedroom makeover | the reveal
My parent's bedroom makeover, officially called "Kim's Coastal Bedroom Makeover" here on the blog, is finally finished!! This is a looooong post, so you might want to get a snack to enjoy while you're reading this one. It's been a long time since I shared the before pictures of this room, so let me give you a then and now … Read More
Kim's coastal bedroom | installing the built-ins
The room makeover for my mom and dad is finally nearing completion! I am planning to photograph the finished room later this week. We finally got over the biggest hurdle in the room, the built-ins. I have assisted Jeff with building cabinets and shelves and I felt like it was something my dad and I could tackle, even though … Read More
Kim's coastal bedroom | non-chippy milk paint
I love the look of paint that has been worn with time. Chips, flakes, rubbed areas that reveal the warm patina of the wood underneath. It just speaks to me. But, I know some people look at those pieces and wonder when you're going to repaint or refinish them. It's just not a look that is up everyone's alley. My … Read More
Sally's farmhouse living room | the before
I mentioned taking on a second makeover as I'm finishing up the one for my mom, but I haven't had the chance to sit down, give it some focused thought (and edit the pictures I took back before Thanksgiving!) As I said, my services are free, but slow. While I haven't sat down with a blank piece of paper to … Read More


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Clarence Roy "Clarence" Brown
April 3, 1925 - March 19, 2008
BROWN Suddenly at Quinte Health Care Prince Edward County Memorial Hospital, on Wednesday, March 19th, 2008, CLARENCE ROY BROWN, of Main Street, Picton, at the age of 82. Beloved husband of the late Earla. Loving father of Stephen and his wife Elizabeth of Ottawa, Paula Clarke and her spouse Andre Lavoie of Kitchener Yvonne Brown and her partner Carmen of Smiths Falls and Robert and his wife Sheila of Ottawa. Dear Brother of Reuben, Carmen, Doreen, Patricia, Dale, Sheila and Wayne. Loved grandfather of Cara, Michael, Travis, Cassandra, Christopher and his great grandchildren Dominick and Chad. A CELEBRATION OF CLARENCE'S LIFE, WILL BE HELD AT THE ROYAL CANADIAN LEGION BRANCH #78, PICTON, on Saturday, March 22nd at 10:30 A.M. Padre Stan Whitehouse Officiating, If desired, donations to the Royal Canadian Legion Branch #78 would be appreciated by the family. (CHEQUES ONLY PLEASE). ARRANGEMENTS ENTRUSTED TO, THE WHATTAM FUNERAL HOME, 33 MAIN STREET, WEST, PICTON.


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Okay. I'll admit it. I laughed when I heard the story.
Two Tennessee women who accused a man of rape have admitted to cops that they had consensually agreed to sex with him in exchange for a pack of cigarettes. One woman told investigators that the duo filed a phony police report because they "didn't enjoy the sex," according to cops.You have to admit, the image of these two heinous water buffaloes prostituting themselves for cigarettes, then claiming rape before owning up to their fraud is chuckle-worthy. That is, until you think through the consequences that potentially faced the poor gentleman (and, boy, do I use THAT term loosely) who managed to achieve and maintain arousal with those two fugly hosebags.
Two counts of rape. The average sentence for an individual convicted of rape is 11.8 years. A casual interwebs search found sentences between 11 and 20 years for two counts of rape.
"Oh c'mon, Vulture! There's no way he would have been prosecuted!" Really? You're telling me that some Mike Nifong wannabe wouldn't press charges? You're telling me that some unscrupulous prosecutor wouldn't hide exculpatory evidence to ensure that their "won-loss record" wouldn't take a hit? You're telling me that a jury of "his peers" (read: people not smart enough to get out of jury duty) couldn't be persuaded by an emotional pair of women tearfully recounting how this man had "deflowered" them?
In 21st century America there is NO situation where being charged with a crime is the slightest bit funny. Because in 21st century America our tangled legal system seems to be designed to make criminals of us all rather than to assure the safety of the citizenry. And in that sort of legal system, no one is safe from malicious, fraudulent, or mistaken prosecution. No one.
So laugh if you will at the hideous HURTings now charged with filing a false police report. But I'm not laughing. Not as long as our system of laws is as effed up as it is right now. Not as long as innocent people can have their lives ruined by false allegations in a system run amok. And certainly not as long as people like this can practice law.


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Western Trauma Association WTA
The Western Trauma Association is committed to the improvement of trauma care through research, education, sharing of clinical experiences, and the development of physicians of all specialties who are involved in the care of trauma patients.
The goals of the Association are not only the intellectual growth attained through increased knowledge, but also the emotional growth attained through camaraderie and interaction with family and friends in an environment conducive to winter sports.
1741 Newnan Crossings Blvd E Ste O, #204
Newnan, Georgia 30265
United States


text: Print | Resources > Trade Shows Resources Trade Shows PPG TRUEFINISH® Industrial Coatings also participates in major industry trade shows and events throughout the year, enabling you to see our products and to speak face-to-face with our technical experts. See below on where to find us at one of these events: Frame Building Expo Feb. 26-28, 2020 Des Moines, IA NCIA 2020 National Conference Apr. 6-8, 2020 Austin, TX Shed Builder Expo Oct. 1-2, 2020 Grand Rapids, MI NAWLA/2020 Traders Market Nov. 4-6, 2020 Columbus, OH Fabtech Nov. 18-20, 2020 Las Vegas, NV TDS/MSDS Literature News Room Trade Shows


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Guitar/bass player, singer, performer, teacher, songwriter. Available as musical entertainment for all events.
University of North Texas graduate with a bachelors degree in music theory. Over 20 years of professional experience in performing/teaching. Performed in all major venues in the DFW area as well as world wide. Taught daughter of Don Henley and son of Nia Peeples. All styles and levels.
Worked in the television industry for 5 plus years. 4 short films written/directed/produced by myself.
Do you have questions about what I can do for your event? Are you interested in collaborating on a project? Send me a message, and I will get back to you soon.
Copyright © 2018 Eric Sykes - All Rights Reserved.


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Humorous Perceptions, Apprenticeships, Making Things and the Transportation of Goods (Case 9, nos. 213-244)
Tradesmen were often depicted, whether in books, journals, prints or in their own trade cards. They were also not infrequently the butt of humour. Many humorous prints relate to barbers, but more for the wigs of the customers than for the practice of their own trade.
Valentine writers (books of verses intended to be sent on St Valentine�s Day) related to many social spheres and relied heavily on puns relevant to the intended recipient. Example of valentine writers for tradesmen are at nos. 215 and 216.
Popular prints would show craftsmen, such as basket makers, coopers or brick makers, at their trade. These prints are not humorous and their aim seems to have been to instruct the public, often the juvenile public, in how things were made.
In order to exercise a trade, an apprenticeship had to be served. Trade cards occasionally give valuable information about a tradesman�s former master, or advertise for an apprentice.
The trade cards showing the skills of several craftsmen are mainly 19th century. Those of Tatlow & Johnson (no. 223) and Benjamin Pearkes (no. 27) are early (1760s) examples of the genre.
Transportation of Goods
Much of the end of the section relates to the transport and warehousing of goods, as important to trade in the 18th and 19th centuries as it is today. When so much was conveyed by sea, and so many consumables had to be imported, complicated arrangements had to be made for the storage of goods and their conveyance to and from the provinces. Goods would be shipped around the coast of Britain and brought inland from ports. London was very busy and it could take a week to get from London Bridge to Blackwall by river. The roles of wharfinger, warehouseman and shipping agent were crucial for the conveyance of goods to the eventual tradesman.


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A Safe Approach
A fter Hurricane Sandy, Long Island's flood levels have been drastically revised. Ensuring your home is in a safe spot is essential in many areas. Whatever reason you need to raise or move a building, we make the process easier with complete service. Lifting a home may sound easy but it is extremely difficulty.
Fortunately, our JMD Construction Group has been lifting homes for years on Long Island.
Don't wait for the next storm before you take action. Call us today for a free home lift evaluation and have peace of mind.


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36. Write five favorite memories of me and Charlie and attach to five red heart balloons on our anniversary.
One night after work, Charlie surprised me with a bouquet of balloons and wrote his five favorite memories. What a sweetie! I have no problem sharing how much I love my husband, but I like to keep personal details private. Which means I'm not sharing Charlie's favorite memories of us.
Because Charlie and I were in Las Vegas over our anniversary weekend, I didn't have a chance to buy five balloons and rank my favorite memories. Due to certain limitations (transportation and part-time job), I haven't had a chance to buy balloons and surprise my amazing husband.
Categories: 2014 Resolution: 40 Before 40, Jennifer Elliott


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Naperville IL: Directed by Supna Chaudhari Jain, Avegh dance troupe presented "The Making Of A Bahu", a journey of loss and recovery of identity on September 9 and 10. Aavegh took the more than 300 people in the audience on a journey familiar to many Indian women: growing up to be educated and independent and suddenly transitioning to the submissive role of daughter-in-law once married.
The show was an effort to explore issues like the expected role of daughters-in-law and its consequences, as well as the role of society and women in perpetuating these expectations and what could be done to change the dialogue.
The dances depicted various phases of a woman's journey from being a little girl to a daughter-in-law, a wife and a mother. Each segment was complemented with original artwork and quotes from Indian women interviewed as part of research conducted by Jain, the artistic director who is the Instructor of Communication at North Central College, and Mara K. Berkland, professor of communication at North Central College. Their research is entitled "Making of the Hollow Bahu: The Web of Influence on Bahu Disempowerment."
The dance program was followed by an invigorating and sometimes passionate exchange of dialogue between the researchers and the audience who expressed their thoughts and impressions on the dances, artwork, and research and on what can be done to change the dialogue.
"The concept of marriage as presented in Bollywood movies and soap operas versus the real-life marriage differ in many ways both good and bad," said one of the attendees, adding, "While it's easy to think it's no longer the case, the status quo towards women today is still flawed."
Proceeds from this production will be donated to Aavegh's local nonprofit partner Bridge Communities. The mission of Bridge Communities is to transition homeless families to self-sufficiency by working with partners to provide mentoring, housing, and supportive services. The adopted families are usually homeless mothers and their children who have been victims of domestic violence or poverty.
Aavegh has been helping local and worldwide nonprofits since 2005, according to the organization.


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I first became aware of the HBA when a former colleague received the Rising Star award. Out of curiosity, I carried out some research and quickly discovered that it is a network offering experiential leadership and professional development opportunities for all career levels. It was a perfect match for someone in the early stages of their career, full of energy and eager to learn more.
In 2014, I joined the HBA as a marketing volunteer, the only youngster at that time among a group of very experienced leaders. I have since held a number of different leadership positions with the most recent one chapter president for the Frankfurt area for the past two years. When I was approached to take on that challenge, the chapter was in a quite difficult situation. I had to start from scratch. But thanks to senior leaders like Kathrin Schoenborn, I was able to build the' next generation of volunteers for the HBA in the Frankfurt region. I learned what elements a high performing team needs and that in a volunteering world not everything is perfect, which is absolutely fine.
Sometimes, the role of chapter president felt like a second job, on top of my real, job but I loved it. I loved spending my Sunday mornings with energetic and passionate people who want to make a difference in the healthcare industry, by strongly believing and acting on gender parity.
The three takeaways, I want to share as a leader of teams in a volunteering world are:
- focus on relationship building instead of simple networking
- connections based on shared interest, goals and trust are the most powerful.
- have the courage to let things go
- providing the stage for someone else lets you shine even brighter.
- believe in the power of diversity
- the more, the merrier and better the outcome.
The three takeaways on how my role at the HBA influenced…
- my approach to new opportunities
- I learned not to hesitate too much and say yes to new opportunities, even though timing might not be perfect.
- my leadership style
- I was able to gain initial leadership experience, by leading a team of 12 volunteers. I learned to delegate more and never forget about the power of motivation.
- my career
- I met so many inspiring leaders along my way, expanded my professional network and built trustful relationships. All in all, I was able to boost my professional career at the same time I advanced in my HBA career.
After almost five years of volunteering, I am happy that we have found a successor Julia Speicher - my partner in crime for the past years. Julia, enjoy the ride on the HBA career rollercoaster, one which enabled me to grow beyond my horizon. A big thank you to my whole team – each one of them with a great personality and high potential to make a difference in the healthcare industry and also to the whole HBA Europe team – inspiring leaders all of them.


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When searching for answers leave the letters that you don't know blank! E.g. B OTH R (BROTHER)
Endless journey made free is a crossword clue for which we have 1 possible answer and we have spotted 1 times in our database. This crossword clue was last seen on 22 November 2019 in The Sun Cryptic Crossword puzzle!


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ID: 0167 - Apartments / Complex in Golden Sands
Location: Golden Sands
Size from: 47 sq. m.
Type: Apartment
Price Price starts from:
Send to friend
General information
Payment plan
Property management
DescriptionThe complex is situated in the north part of Golden Sands resort directly on the white sands of Black Sea Coast and near the yacht port.
The unique location and impressive architecture of the hotel, along with its great number of amenities, facilities and extras of this hotel features makes it an enjoyable place to stay.
An overall atmosphere of beautiful, seaside serenity delight the guests since the first moment. In addition, area attractions and venues that guests would like to experience are all around.
DetailsModern hotel complex (4 stars) consisted of 276 standard and family rooms and apartments situated at two parts - 6 storied building (newly constructed part) and 11 storied building (completely renovated part).
First-class studios and apartments with sea view
After spending peaceful days on the beach, a long day of sightseeing, business or pleasure, guests will look forward to retiring to the tastefully furnished hotel rooms, which are well equipped to meet the needs and expectations of modern travellers. Each spacious, comfortable room is beautifully decorated and all rooms offer a full range of modern amenities like air-condition, direct dial telephone, mini bar , SAT-TV, hair dryer, black-out curtains, shower or bath, balcony. Rooms with sea- and park view.
Equipped and furnished like the standard rooms but much more spacious, with lounge area and possibilities for accommodation of a third/ fourth person.
With area more than 50 sq. m. and equipped and furnished like the standard rooms but with an extra living/sleeping room for a third/fourth person. All apartments are with a sea view.
Facilities and amenities:
- parking
- rent-a-car
- laundry service
- safety deposit boxes
- business centre
- gift shops
- restaurant with a sunny terrace and live music (a-la-carte restaurant)
- bars (lobby bar, fitness bar, pool bar)
- hairdressers
- exchange office
- internet
Guests can find at the hotel: fitness hall, sauna, massage, medical services, beauty salon, in- and outdoor swimming pools with mineral water, sun beds with matraces, sun umbrellas and beach towels
Sport and entertainment:
The complex offers games and entertainments for kids
- in- and outdoor swimming pools, sun beds, sun umbrellas and beach towels
- billiard, table tennis, darts
- internet
- sauna, fitness hall
- morning- and water gymnastics
- animation program and evening shows
- tennis court in LTI – Berlin Green Park Hotel
Wellness center:
- medical cosmetics
- aromatherapy, massage
- medical services
- hairdressers
Business center:
- Hall Sofia - 15 seats.
- Hall Berlin – up to 100 seats, depending on the layout. Equipped with a flip chart.
- Possibilities for hiring of a multimedia, overhead projector, microphones and for interpreting services.
- Organizing of transfers, excursions and related social events, by request.
- Business services (fax, internet, copying, printing, secretarial services).
Facilities for children:
- playground
- children pool
Payment planReseravtion fee – 2 000 Euro
100 % from the purchase price of the apartment due 1 month.
There are available individual payment plans on request.
DiscountsBuy apartments or villas in resort Golden Sands through our company, "FMF properties" and get a discount of 5%, which is not bound in any way with the concessions given to investors.
To receive the discount upon purchase of an apartment or villa in resort Golden Sands given personally by our company, "FMF properties" you must do the following:
Send us E-mail: firstname.lastname@example.com
- Phone number to contact you
- Your passport data
- The number of studio or apartment you have chosen in the complex
- The scheme of payment which you are most comfortable
- Short text in which they would like to receive a discount given personally by our company
Once you send us an email with the information requested by us, we will contact you by phone to explain your in details all the other things that interest you to start purchasing your desired apartment.
Property management8 Euro/sq. m. annually. Price include VAT
Rentalthe complex offers rental agreement.


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Friday's election-interference indictment by U.S. special counsel Robert Mueller underscores how thoroughly U.S. social-media companies like Facebook and Twitter were played by Russian propagandists.
And it's not clear if the companies have taken sufficient action to prevent something similar from happening again.
Thirteen Russians, including a businessman close to Vladimir Putin, were charged Friday with plotting to interfere in the 2016 U.S. election through social media propaganda. Their alleged aims included helping Republican Donald Trump and harming Democrat Hillary Clinton.
Twitter declined comment Friday, but Facebook says it's grateful to the U.S. government for taking "aggressive action." Facebook also says it's doing more to prevent future attacks by hiring more people to work on security and collaborating with the FBI and others. Experts are skeptical that will work.
Source: abcnews.go.com


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20-race 2015 calendar surfaces at Monza
A preliminary calendar for 2015 is doing the rounds in the Monza paddock.
The schedule, first published by Speed Week after seeing it at the scene of the Italian grand prix, features all 19 grands prix that are on this year's calendar, plus Mexico, with the old Mexico City layout set to host a race in late October.
"The track only needs to be resurfaced," Bernie Ecclestone told reporters earlier at Monza.
But according to Speed Week, many of the dates on the provisional 2015 calendar - currently featuring an unprecedented 20 races - are in fact not set in stone.
Organisers of the Australian grand prix, however, are already advertising next year's Melbourne race, reportedly to open the world championship as usual, for March 15.
And the report said Abu Dhabi will once again host the finale at the end of November.


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My skin was never close to perfect, I have had random pimples growing on my face now and then. My skin condition worsened when I first entered NTU last year and started staying in hall ... Sleeping irregular hours and sleeping in a non air-conditioned room killed my skin. Pimples appear regularly and its quite rare to see my face being clear of pimples. Also, those pimples left quite some scars and marks on my face :(
I went to The DRx Clinic last week for my first skin consultation. Yes, I don't want to live with pimples or pimple scars on my face anymore, hence the decision to seek professional help. I've heard many good reviews about The DRx Clinic online, especially from those people who are fighting acne and I can't wait to witness the positive results on myself! Will be sharing the progress of my skin's condition on my blog in the following weeks to come so keep reading!~
We have to go there without wearing make up for proper skin analysis. I hid behind my geek specs on my way there haha! (This photo is edited, hence the perfect skin.)
The DRx Clinic is located at the 16th level of Tong building, which is conveniently in between Lucky plaza and Paragon, about 5-10 minutes walk from Orchard MRT station. Quite easy to find them even for people who always get lost (like me hehe). They actually own the whole 16th floor - the clinic on one half and the Mediaspa on the other half!
Was greeted with a clean and classy interior as well as the reception area once I entered the clinic.
Since it was my first time there, I had to fill in the Patient's Registration Form which is about one page long. Apart from personal particulars and contact details, they also have some questions that make you feel like they really care about you... Questions like how do we want to be addressed, our preferred spoken language, and even which type of magazines will we like to see in the waiting room!
The clinic was quite crowded, considering the fact that I was there on a weekday afternoon. However, the waiting time was quite short as we have to make appointments before going down for our consultations.
The DRx Clinic carries Derma-Rx products!
Was ushered into the consultation room and my doctor is Dr David Ng! He's quite friendly and even chatted a little with me. When he asked about my skin concerns, I told him that my main concern was pimples and scars left behind by pimples. He took a closer look at my skin with his magnifying glass + light device and proceeded to tell me about my skin problems - my skin is a little on the oily side and I have some clogged pores apart from pimples and marks. He also mentioned that mine wasn't a very big problem so I was secretly relieved deep inside! He went on to prescribe me some products to use at home and also explained to me what they are for.
Here's a photo Dr David Ng and me!
After that, I went to the briefing rooms and the consultant explained to me how to use the products step by step. The consultant was in the consultation room during consultation with Dr David Ng the whole time so she knows what products I was prescribed, no worries about getting the wrong products.
She also wrote down the steps in a booklet for me to bring home, good for super forgetful people like me!
Its time to take photos next! Not camwhoring, but photos of our full face without make up and with our fringe up. These photos are for them to record and track the progress of our skin condition. Hopefully, I will have nicer skin for them to take photo of in my next visit! :)
After taking photos, I was supposed to wait at the waiting area to collect my prescribed products, but I didn't even get to sit down before my name was called, how efficient! Here are the products which I brought home!
I actually explored the clinic and medispa a little, shall share some photos of the other parts of the clinic!
One of the treatment rooms..
A separate private waiting area for patients doing laser treatment, for them to rest and wait for the numbing cream to set in, how thoughtful of The DRx Clinic right!
Make up area for ladies who want to put on their make up after doctor's consultation!
Excited to start on The Derma-Rx regime!! :D
Here are the products which I was prescribed, just in case you wanna know! I'm actually giving up my usual skincare routine and the huge store of skincare products that I have at home just for this Derma-Rx regime for maximum result and efficacy.
- Milk Cleanser
- Foaming Cleanser
- Toner
- Comedone Formula
- Liposomal Sunscreen
- Acne Spot Lotion
- X cream
- Samples of: Hydrator and Alpha-Beta Gel
Been using these products for a week now and my skin is already getting better! I'll do a more detailed review on them again when I have used them for a longer period of time.
The DRx Clinic
Website: http://www.drxclinic.com/
Facebook: https://www.facebook.com/TheDRxClinic
Tel: 6733 1555