PMC2635918_01
PMC2635918_02
PMC2635918_03
PMC2635918_04
PMC2635918_05
PMC2635918_06
PMC2635918_07
PMC2635918_08
PMC2635918_09
The extent of the lesions in these patients as reconstructed on the International Consortium of Brain Mapping single subject template image. No scan was available for P3.
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F1
Three participants took part in this experiment: P1, P2, and P7. (see Figure 1).
Temporal bias does not influence point of maximal extinction. (A) Experiment 1: the proportion of correctly reported contralesional stimuli under conditions of double presentation with different temporal asynchronies. Each line illustrates the performance of an individual participant. In this experiment, double stimulation trials straddle the fixation, but with a high proportion of presentations with a ipsilesional lead. The stimulus onset asynchronies (SOA) are expressed from the left stimulus having an onset a prior to the right (a negative value), to the right stimulus having an onset prior to the left (a positive value). The SOAs are expressed in units of stimulus durations, which was titrated between participants (P2 = 600ms, P5 = 480ms, P6 =300ms). Note that maximal extinction is observed near objective simultaneity (SOA = 0). (B) Results from experiment 1: the proportion of correctly reported contralesional stimuli under conditions of double presentation with different temporal asynchronies. This experiment is similar to Experiment 1, except that there was a preponderance of stimulus pairs with a contralesional lead. The target durations were 400ms of P1, 600ms for P2 and 400ms for P7. Note that again maximal extinction is observed near maximal simultaneity.
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F2
The effects of varying the asynchrony of the two stimuli are shown in Figure 2A. The effects of varying the asynchrony of the two stimuli are shown in Figure 2B.
Spatial bias influences extinction. The vertical axis shows the participant's accuracy, while the horizontal axis shows the temporal asynchrony between the relatively left and right targets (e.g. -400 suggests that the leftmost target appears 400 ms prior to the rightward target). (A) The solid line shows P9's performance on spatially unbiased blocks, where targets straddled fixation. The dotted line show's this individual's performance on spatially biased blocks where both targets appeared in the ipsilesional hemifield. Note that the point of maximal extinction shifts when items are presented in the ipsilesional hemifield. (B) Performance of participants P3, P4 and P8 on spatially biased trials. Note that all individuals perform worst at positive SOAs (e.g. when the more peripheral and ipsilesional right item occurs before the more foveal and relatively contralesional item).
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F3
The effects of varying the asynchrony of the two stimuli are shown in Figure 3. P9 on spatially biased versus spatially unbiased blocks, while the lower panel (Figure 3B) shows the performance of the P3, P4 and P8 with the spatially biased trials. P3 X2 (6) = 33.299, p < 0.00001; P4 X2 (6) = 17.032, p < 0.00917; P8 X2 (6) = 34.978, p < 0.00001; P9 during biased blocks X2 (6) = 54.067, p < 0.00001; P9 during unbiased blocks X2 (6) = 50.588, p < 0.00001.