research on the topic was heavily focused on early selection, research since the late 1970s has been shifted mainly to the late selection theories. This change resulted primarily from a shift in paradigms used to study inattentional blindness which revealed new aspects of the phenomenon. Today, late selection theories are generally accepted, and continue to be the focus of the majority of research concerning inattentional blindness. Evidence for late selection A significant body of research has been gathered in support of late selection in the perception of visual stimuli. One of the popular ways of investigating late selection is to assess the priming properties (i.e. influencing subsequent acts) of unattended stimuli. Often used to demonstrate such effects is the stem completion task. While there exist a few variations, these studies generally consist of showing participants the first few letters of words, and asking them to complete the string of letters to form an English word. It has been demonstrated that observers are significantly more likely to complete word fragments with the unattended stimuli presented in a trial than with another similar word. This effect holds when stimuli are not words, but instead objects. When photos of objects are shown too quickly for participants to identify, subsequent presentation of those items lead to significantly faster identification in comparison to novel objects. A notable study by Mack and Rock has also revealed that showing a word stimulus differing from the participant's name by one letter did not generally call conscious attention. By simply changing a character, transforming the presented word into the observer's first name, the now highly meaningful stimulus is significantly more likely to be attended to. This suggests that the stimuli are being extensively processed, at least enough to analyze their meaning. These results point to the fact that attentional selection may be determined late in processing. The evidence outlined above suggests that even when stimuli are not processed to the level of conscious attention, they are nonetheless perceptually and cognitively processed, and can indeed exert effects on subsequent behavior. Evidence for early selection While the evidence supporting late selection hypotheses is significant and has been consistently reproduced, there also exists a body of research suggesting that unattended stimuli in fact may not receive significant processing. For example, in a functional magnetic resonance imaging (fMRI) study by Rees and colleagues, brain activity was recorded while participants completed a perceptual task.