Objective:For 3,670 stroke patients from the United Kingdom, United States, Australia, Belgium, and Italy, we performed a genome-wide meta-analysis of white matter hyperintensity volumes (WMHV) on data imputed to the 1000 Genomes reference dataset to provide insights into disease mechanisms.Methods:We first sought to identify genetic associations with white matter hyperintensities in a stroke population, and then examined whether genetic loci previously linked to WMHV in community populations are also associated in stroke patients. Having established that genetic associations are shared between the 2 populations, we performed a meta-analysis testing which associations with WMHV in stroke-free populations are associated overall when combined with stroke populations.Results:There were no associations at genome-wide significance with WMHV in stroke patients. All previously reported genome-wide significant associations with WMHV in community populations shared direction of effect in stroke patients. In a meta-analysis of the genome-wide significant and suggestive loci (p < 5 × 10−6) from community populations (15 single nucleotide polymorphisms in total) and from stroke patients, 6 independent loci were associated with WMHV in both populations. Four of these are novel associations at the genome-wide level (rs72934505 [NBEAL1], p = 2.2 × 10−8; rs941898 [EVL], p = 4.0 × 10−8; rs962888 [C1QL1], p = 1.1 × 10−8; rs9515201 [COL4A2], p = 6.9 × 10−9).Conclusions:Genetic associations with WMHV are shared in otherwise healthy individuals and patients with stroke, indicating common genetic susceptibility in cerebral small vessel disease.

Comprehensive AF genetic risk scores were specific for cardioembolic stroke. Incomplete workups and subtype misclassification may have limited the power to detect associations with strokes of undetermined pathogenesis. Future studies are warranted to determine whether AF genetic risk is a useful biomarker to enhance clinical discrimination of stroke pathogeneses.

BackgroundAutistic individuals commonly show circumscribed or “special” interests: areas of obsessive interest in a specific category. The present study investigated what impact these interests have on attention, an aspect of autistic cognition often reported as altered. In neurotypical individuals, interest and expertise have been shown to result in an automatic attentional priority for related items. Here, we examine whether this change in salience is also seen in autism.MethodsAdolescents and young adults with and without autism performed a personalized selective attention task assessing the level of attentional priority afforded to images related to the participant’s specific interests. In addition, participants performed a similar task with generic images in order to isolate any effects of interest and expertise. Crucially, all autistic and non-autistic individuals recruited for this study held a strong passion or interest. As such, any differences in attention could not be solely attributed to differing prevalence of interests in the two groups. In both tasks, participants were asked to perform a central target-detection task while ignoring irrelevant distractors (related or unrelated to their interests). The level of distractor interference under various task conditions was taken as an indication of attentional priority.ResultsNeurotypical individuals showed the predicted attentional priority for the circumscribed interest images but not generic items, reflecting the impact of their interest and expertise. Contrary to predictions, autistic individuals did not show this priority: processing the interest-related stimuli only when task demands were low. Attention to images unrelated to circumscribed interests was equivalent in the two groups.ConclusionsThese results suggest that despite autistic individuals holding an intense interest in a particular class of stimuli, there may be a reduced impact of this prior experience and expertise on attentional processing. The implications of this absence of automatic priority are discussed in terms of the behaviors associated with the condition.Electronic supplementary materialThe online version of this article (doi:10.1186/s13229-017-0132-1) contains supplementary material, which is available to authorized users.

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.