Artificially created stimuli produced by a genetic algorithm using a saliency model as its fitness function show that Inattentional Blindness modulates performance in a pop-out visual search paradigm

Salient stimuli are more readily detected than less salient stimuli, and individual differences in such detection may be relevant to why some people fail to notice an unexpected stimulus that appears in their visual field whereas others do notice it. This failure to notice unexpected stimuli is termed 'Inattentional Blindness' and is more likely to occur when we are engaged in a resource-consuming task. A genetic algorithm is described in which artificial stimuli are created using a saliency model as its fitness function. These generated stimuli, which vary in their saliency level, are used in two studies that implement a pop-out visual search task to evaluate the power of the model to discriminate the performance of people who were and were not Inattentionally Blind (IB). In one study the number of orientational filters in the model was increased to check if discriminatory power and the saliency estimation for low-level images could be improved. Results show that the performance of the model does improve when additional filters are included, leading to the conclusion that low-level images may require a higher number of orientational filters for the model to better predict participants' performance. In both studies we found that given the same target patch image (i.e. same saliency value) IB individuals take longer to identify a target compared to non-IB individuals. This suggests that IB individuals require a higher level of saliency for low-level visual features in order to identify target patches

Interplay between supramodal attentional control and capacity limits in the low-level visual processors modulate the tendency to inattention

When engaged in a demanding task, individuals may neglect unexpected visual stimuli presented concomitantly. Here we use a change detection task to show that propensity to inattention is associated with a flexible allocation of attentional resources to filter and represent visual information. This was reflected by N2 posterior contralateral (N2pc) and contralateral delay activity (CDA) respectively, but also during high-order reorienting of attentional resources (known as anterior directing attention negativity, ADAN). Results show that differences in noticing and failing to notice unexpected stimuli/changes are associated with different patterns of brain activity. When processing (N2) and working memory (CDA) capacities are low, resources are mostly allocated to small set-sizes and associated with a tendency to filter information during early low-level processing (N2). When resources are high, saturation is obtained with larger set-sizes. This is also associated to a tendency to select (N2) and reorient resources (ADAN) to maintain extra information (CDA)

Development of second order Theory of Mind: assessment of environmental influences using a dynamic system approach

Theory of Mind (ToM) refers to the ability to attribute beliefs to oneself and others. The present study used a dynamic systems approach to assess how environment may affect the development of second-order ToM (e.g., John knows that Mary knows that he went out yesterday). ToM is divided into two major dimensions: comprehension (i.e., to understand a mental state) and prediction (i.e., to predict someone else’s future behaviour or mental state). Two age groups were assessed: 5-6 and 10-11 years old children. In both age groups, participants were assigned to a condition of “Support” (help provided) or “Non-Support” (help not provided). Results show that second-order ToM follows a dynamic growth law that depends on support. Support facilitates performance in ToM production (i.e., to predict one’s future behaviour) for both the 5-6 and 10-11 year old children. Interestingly, the 5-6 year olds who received support presented an increase in the second-order prediction performance at the expense of the second-order comprehension, suggesting that a temporary dip in comprehension performance may facilitate the development of mental rules to predict one’s future behaviour