Spatial navigation from same and different directions: The role of executive functions, memory and attention in adults with autism spectrum disorder

Mental rotation and language in autism spectrum disorder

Though visuospatial skills are often considered a relative strength in autism spectrum disorder (ASD), unexplained difficulties relative to neurotypical (NT) peers have also been observed. Dissociations between spatial cognition and language skills in ASD may explain these difficulties given that these systems are linked in NT individuals. The current study examined performance on a mental rotation task that systematically varied stimulus features and the degree to which performance was associated with language in ASD relative to NT peers. Participants were children and young adults with ASD and 25 pairwise age- and IQ-matched NT peers (p's>0.53). The mental rotation task involved four conditions: two-dimensional (2D) abstract figures, three-dimensional (3D) abstract figures, 2D common objects, and 3D common objects. Structural language was measured using the grammar subscale from the Test of Language Development: Intermediate adapted for Norwegian. Mixed-effects model results indicated that autistic individuals were less accurate and had slower reaction time across mental rotation task conditions than NT peers. Language was associated with mental rotation accuracy for both groups across conditions, but with reaction time only for the NT group. The current study demonstrated selective associations between language and performance on a classic spatial cognition task in autistic individuals. Namely, there was a dissociation between language and in-the-moment efficiency in the ASD group, and this dissociation may reflect a broader dissociation between visuospatial and language systems.

Hippocampal contributions to social and cognitive deficits in autism spectrum disorder

Autism spectrum disorder (ASD) is characterized by hallmark impairments in social functioning. Nevertheless, nonsocial cognition, including hippocampus-dependent spatial reasoning and episodic memory, is also commonly impaired in ASD. ASD symptoms typically emerge between 12 and 24 months of age, a time window associated with critical developmental events in the hippocampus. Despite this temporal overlap and evidence of hippocampal structural abnormalities in ASD individuals, relatively few human studies have focused on hippocampal function in ASD. Herein, we review the existing evidence for the involvement of the hippocampus in ASD and highlight the hippocampus as a promising area of interest for future research in ASD.

Maternal immune activation targeted to a window of parvalbumin interneuron development improves spatial working memory: Implications for autism

Maternal immune activation (MIA) increases risk for neuropsychiatric disorders such as autism spectrum disorder (ASD) in offspring later in life through unknown causal mechanisms. Growing evidence implicates parvalbumin-containing GABAergic interneurons as a key target in rodent MIA models. We targeted a specific neurodevelopmental window of parvalbumin interneurons in a mouse MIA model to examine effects on spatial working memory, a key domain in ASD that can manifest as either impairments or improvements both clinically and in animal models. Pregnant dams received three consecutive intraperitoneal injections of Polyinosinic:polycytidylic acid (poly(I:C), 5 mg/kg) at gestational days 13, 14 and 15. Spatial working memory was assessed in young adult offspring using touchscreen operant chambers and the Trial-Unique Non-matching to Location (TUNL) task. Anxiety, novelty seeking and short-term memory were assessed using Elevated Plus Maze (EPM) and Y-maze novelty preference tasks. Fluorescent immunohistochemistry was used to assess hippocampal parvalbumin cell density, intensity and co-expression with perineuronal nets. qPCR was used to assess the expression of putatively implicated gene pathways. MIA targeting a window of parvalbumin interneuron development increased spatial working memory performance on the TUNL touchscreen task which was not influenced by anxiety or novelty seeking behaviour. The model reduced fetal mRNA levels of Gad1 and adult hippocampal mRNA levels of Pvalb and the distribution of low intensity parvalbumin interneurons was altered. We speculate a specific timing window for parvalbumin interneuron development underpins the apparently paradoxical improved spatial working memory phenotype found both across several rodent models of autism and clinically in ASD.

Tell me where it is: Selective difficulties in spatial language on the autism spectrum

LAY ABSTRACT

How we think and talk about space is an essential ability, necessary for understanding the world around us. We recruit spatial thinking every day when finding our way or using tools but also in more advanced tasks, such as reading complex graphs or maps. We do so also in daily communication when we use spatial language, terms such as under, over, to the left of or in front of, and when we give instructions. Spatial terms appear in children's early vocabularies and continue to develop until late childhood or even early adolescence. Because spatial language develops over many years, some spatial terms are mastered very early, whereas others take longer to acquire. In the current set of studies, we tested how intellectually high-functioning children and adults on the autism spectrum use and understand these early- and late-acquired spatial terms in comparison to typically developing age-matched individuals. We found that children and adults on the autism spectrum experience difficulties with the use of some spatial terms (e.g. near and far or out of and down off) but not with others, which are acquired early (e.g. in and on or over and under). We also found that remembering spatial terms from short stories was more difficult for the individuals on the autism spectrum compared with typically developing individuals. These results reveal difficulties that can profoundly affect everyday communication of children and adults on the autism spectrum but also open new directions of research on language development in autism spectrum disorders.

Children with ASD Show Impaired Item-Space Recollection, But Preserved Item-Color Recollection

Although individuals with autism spectrum disorder (ASD) have been often shown to display similar memory performance on semantic memory tasks compared to typically developing (TD) children, there is ongoing debate about whether and how their ability to remember specific past events (i.e., episodic memory) is impaired. We assessed a sample of 62 children with ASD and 72 TD children, ranging in age between 8 and 12 years on 2 memory tasks. Participants encoded a series of images and their association with either where they appeared on the screen (item-space association task) or with the color of an image's border (item-color association task). Children with ASD showed worse memory in the item-space association task compared to their TD peers, but comparable memory for the item-color association task. These differences persisted when age, intellectual quotient, and general item recognition memory were accounted for statistically. We interpret these results in light of evidence for specific deficits along the dorsal stream affecting processing of spatiotemporal information in ASD. Autism Res 2020, 13: 1985-1997. © 2020 International Society for Autism Research and Wiley Periodicals LLC LAY SUMMARY: Episodic memory requires the ability to bind contextual details (such as color, location, etc.) to an item or event in order to remember the past with specific detail. Here, we compared children with autism spectrum disorder (ASD) and typically developing (TD) children on tasks examining episodic memory. Children with ASD recalled more poorly previously seen items and their associated space-related details, but they performed comparably to TD children on color details. We discuss the possible mechanisms that contribute to worse spatial processing/recall in ASD.

Public transport planning tool for users on the autism spectrum: from concept to prototype

PURPOSE

This research explored the challenges of public transport use for individuals on the autism spectrum. It, subsequently, proposed a mobile application solution, coproduced by individuals on the autism spectrum, to facilitate public transport use.

METHODS

We, first, conducted a review of the literature to highlight the challenges people on the autism spectrum face when utilizing public transport. We, then, designed a list of mobile application functionalities that address the identified problems. To validate these functionalities, 27 young autistic adults and 19 families of autistic individuals were employed. Finally, based on the findings, we designed a mobile application that helps facilitate public transport use for those on the autism spectrum.

RESULTS

We found that the most prevalent concerns, in public transport use, amongst autistic individuals and their families are safety and spatial awareness. Specific problems include finding one's way to the bus stop, boarding the correct service and disembarking at the correct stop. Interestingly, anxiety about unexpected events was also a barrier. Sensory sensitivity, similarly, was found to be an obstacle.

CONCLUSIONS

This study defined the challenges of public transport use for autistic individuals and proposed a technological solution. The findings can also inform innovators, public transport providers and policymakers to improve public transport accessibility.Implications for rehabilitationPeople on the autism spectrum heavily rely on other individuals, namely family and friends, for their transportation needs. This dependence results in immobility for the autistic individuals and significant time and economical sacrifice for the person responsible for the transportation.Public transport, a cheap and widely available form of transportation, has not yet been clearly studied with individuals on the autism spectrum.We clearly define the challenges of using public transport and put forward a trip planner mobile application, coproduced by autistic individuals, that facilitate it.In the long term, this enhanced travel independence can lead to greater education and employment opportunities and an overall improved quality of life.