Extraction and generalisation of category-level information during visual statistical learning in autistic people

Abstract

Background We aimed to assess whether autistic individuals were able to generalise across contexts when building statistical expectations of their environment to the same extent as non-autistic individuals. We did this by assessing the implicit awareness of statistical regularities in a sequence of naturalistic scene images in both autistic and non-autistic individuals. Methods125 participants (61 participants with an autism diagnosis and 64 non-autistic controls) were presented with a fast serial presentation sequence of images and given a cover task to avoid attention being explicitly drawn to patterns in the underlying sequences. This was followed by a two-alternative forced choice task to assess participants’ implicit recall. Participants were presented with 1 of 3 unique versions of the task, in which the presentation and assessment of statistical regularities was done at either a low feature-based level or a high semantic-based level. ResultsThere were no significant group differences in how performance varied across the 3 conditions, but there was an overall significant reduction in visual statistical learning in the autistic group. There was also a lack of statistical significant effect of learning for the autistic participants who completed the generalisation condition.LimitationsWhile the overall sample was fairly large, the sample sizes for the subgroups within the study were modest, so the lack of statistically significant effect of learning for the autistic participants who completed the generalisation condition may be due to a lack of power rather than a true absence of learning. Additionally, this study did not directly assess if semantic information was being processed to a similar extent by both autistic and non-autistic participants.ConclusionsThese results do not support the claim that autistic individuals experience difficulties in either acquiring or generalising statistic regularities at the category-level, but suggest that differences in visual statistical learning occur in autistic people.

Discrimination sensitivity of visual shapes sharpens in autistic adults but only after explicit category learning

“…), by disregarding heterogeneity within group and by using experimental approaches and stimuli that are not always suitable to study prototype formation [16,21]. In addition, autistic individuals would be slower in learning categories [22], display no typical "discrimination peak" (i.e., no higher discrimination sensitivity across the category compared to within the category; [23]), have difficulties categorizing atypical exemplars [24,28], are less inclined to use an interpolation learning style (i.e., INT: extracting regularities; [12,25]), have reduced generalization of category learning [26,27], or would have difficulties with multi-dimensional categorization (i.e., when stimuli differ on two or more dimensions; [29,30]). Thus far, almost no study has investigated the interplay between perceptual discrimination and category learning, to address sensory and information processing issues in ASC and the underlying mechanisms in a coherent way [18,24,31].…”

Discrimination sensitivity of visual shapes sharpens in autistic adults but only after explicit category learning

“…The results of this research have been con icting due to uncontrolled confounding factors and the use of different experimental approaches and stimuli. In addition, autistic individuals would be slower in learning categories (21), display no typical "discrimination peak" (22), have di culties categorizing atypical exemplars (15), are less inclined to use an interpolation learning style (INT: extracting regularities) (11,23), have reduced generalization of category learning (9,24), or would have di culties with multidimensional categorization (i.e., when stimuli differ on two or more dimensions) (26,27). Thus far, almost no study has investigated the interplay between discrimination and category learning, to address sensory and information processing issues in ASC and the underlying mechanisms in a coherent way (15,19,28).…”