A summary by Eleanor K Braithwaite.
This work was motivated by a recent study by other members of our group and their colleagues, which found that infant EEG theta changes predicted non-verbal cognitive ability throughout childhood in children at high-risk of autism.
This formed the basis of our hypotheses, which we pre-registered - along with our analysis plan. We also predicted a relationship between change in theta EEG and measures of inhibitory control, motivated by the large body of work which indicates a link between theta activity and cognitive control in adults, and executive functioning in childhood.
We also included an additional measure of EEG theta change and predicted a relationship between change in theta EEG and measures of inhibitory control.
The paradigm was relatively simple: EEG was recorded whilst infants watched a non-social video (i.e. leaves falling). We were interested in (a) whether EEG theta power increased over the course of video viewing and (b) whether the degree of this increase was associated with cognitive measures.
To address (a), we used the comparison measure used in the previous study by Jones et al. (2019) and an additional measure of EEG theta change. The extra measure (which we call Index b) enabled a reduced drop-out rate and allowed for potential differences in the time-frame of EEG changes across individuals. Using Index b, we found that theta increased over the course of video viewing at 6-months-old; extending the previous finding to a younger age. We then used Index b as a measure of theta change in subsequent analyses.
In these analyses we found that the degree of dynamic change (specifically, an increase) in EEG theta power over the frontal brain area at 6-months-old predicted non-verbal cognitive ability at 9-months-old. This seemed to be driven by a relation between theta change and Visual Reception skills, r = 0.50, p = 0.001.
We found no indication of an association between theta change and executive functions (EF). This may be due to the immature development of EF at 6 months, or could indicate that frontal theta is linked specifically to learning mechanisms (rather than cognitive or attentional control) in infancy. More work is needed to draw these apart.
Nonetheless, the finding of a relation between theta modulation and non-verbal cognitive ability is interesting. We suggest that frontal theta might reflect integrative neural processes across attentional, perceptual and memory domains which, when compromised, may lead to sub-optimal basic cognitive abilities in infancy. These may have cascading effects on subsequent learning and cognition.
Frontal theta change may thus have potential as an early neural marker of cognitive development which could be used to identify children who are at risk of less optimal cognitive outcomes. Early identification may facilitate support and intervention for children during optimal periods, enabling difficulties to be countered before broader cognitive difficulties emerge - which is the ultimate goal!
A summary by Teresa Del Bianco
Social Attention - our tendency of focusing on cues with social relevance in the environment, such as eyes and faces - has been long studied by comparing the grand-average of people with some characteristic in common. By measuring the overall Social Attention levels of autistic people, and comparing it with the same measure from neurotypical people, researchers were able to draw general differences, for example, that autistic people, on average, look less at other people's faces and eyes. However, the same analysis revealed outstanding heterogeneity: while less Social Attention characterised Autism as a group, it was difficult to explain why this result could not be easily replicated.
This research tried to capitalise on heterogeneity and implement a method that could help to understand the changes of Social Attention. We unwrapped Social Attention, by looking at the second-by-second change of the looking time on the face, and focused on age, asking ourselves if we could situate this average difference in time.
We found that we could quantify a late peak (after 10-15 seconds of observation passed already) of the looking time to the face, emerging with age (between 6 and 30 years!). This trend was significantly stronger in neurotypical people.
We think that this finding might be related to the specialisation of the social brain towards face processing, derived from accumulating experience with other people. Autistic people might experience external social environment and/or self-directed experience to a less extent, thus not developing a peak as strong as the neurotypicals in this specific time-window. To know more, read our article!
A summary by Georgia Lockwood Estrin
There is increased recognition that autistic women and girls are underserved by the clinical criteria and processes required to receive a diagnosis. A small team of researchers at Birkbeck College and King’s College London conducted a mixed-methods systematic review aimed to identify key barriers to obtaining an Autism Spectrum Disorder (ASD) diagnosis in girls and young women under 21 years.
An initial sample of 795 papers were found by the database searches, and were screened. A total of 13 quantitative, six qualitative and one mixed-methods papers met our inclusion criteria and were included in the review.
Six themes were identified that focused on perceived gendered symptoms as barriers to diagnosis: behavioural problems, social and communication abilities, language, relationships, restricted and repetitive behaviours and interests, and additional diagnoses/difficulties. Five themes were identified as (parental) perceived barriers to diagnosis: compensatory behaviours, parental concerns, others’ perceptions, lack of information/resources and clinician bias.
Our results highlighted that in many cases, for females to be diagnosed, certain behaviours and symptoms had to be exaggerated to sufficiently to warrant a diagnosis. This may be particularly problematic, because females, much more often than males, have been reported to compensate for, or “mask”, aspects of their ASD characteristics. This has been referred to as the ‘camouflage’ hypothesis. For example, at school autistic girls may either intentionally or unconsciously ‘mask’ their social communication difficulties when in social situations. This is a key reason why females may not come to clinical attention and may fail to reach diagnostic thresholds during assessments.
One overarching concept illuminated by this review, and which was continuously highlighted as a barrier that impacted all levels of identification and diagnosis in females, was that of ASD being perceived as a male disorder. Not only did parents initially face disbelief and scepticism from others when expressing concerns about their daughters, often mixed messages were also received from clinicians and health professionals regarding autism characteristics in their daughters.
This review therefore highlights the importance of enhancing widespread understanding and recognition of ASD presentation in both sexes and all genders across development.
Click here to read the review in full!