Brain correlates of declarative memory atypicalities in autism: a systematic review of functional neuroimaging findings.

This study looked at brain scans during memory tasks in autistic people versus non-autistic people. Researchers found that autistic brains show different patterns of activity, with more activity on the left side of the brain, more activity in back brain areas (including the hippocampus which is important for memory), and different processing pathways. These brain differences may explain why autistic people often have stronger verbal memory than visual-spatial memory, and why they may struggle with some types of memory tasks while doing well with others.

This systematic review examined functional neuroimaging studies to understand brain differences during memory processing in autism spectrum disorder (ASD). The review identified three key patterns of brain asymmetries in individuals with ASD compared to typical development: greater left hemisphere activity versus right, increased posterior brain region activity (including hippocampus) versus anterior regions, and preferential ventral stream activation versus dorsal streams. These neural patterns appear linked to specific memory characteristics in autism, including stronger verbal than spatial memory processing, difficulties with active working memory maintenance, and preserved relational memory despite challenges with contextual processing in episodic memory.

These findings suggest memory interventions for autistic individuals should leverage verbal processing strengths while providing additional support for spatial memory tasks. Understanding these neural differences can inform educational strategies and cognitive remediation approaches, potentially improving daily functioning and academic outcomes through targeted memory training programs.

Sample size not reported. The review appears to synthesize existing neuroimaging studies but specific methodological details, study quality assessment, and number of included studies are not provided in the abstract. The confidence in some findings (particularly dorsal vs ventral stream differences) appears tentative.

The long-described atypicalities of memory functioning experienced by people with autism have major implications for daily living, academic learning, as well as cognitive remediation. Though behavioral studies have identified a robust profile of memory strengths and weaknesses in autism spectrum disorder (ASD), few works have attempted to establish a synthesis concerning their neural bases. In this systematic review of functional neuroimaging studies, we highlight functional brain asymmetries in three anatomical planes during memory processing between individuals with ASD and typical development. These asymmetries consist of greater activity of the left hemisphere than the right in ASD participants, of posterior brain regions-including hippocampus-rather than anterior ones, and presumably of the ventral (occipito-temporal) streams rather than the dorsal (occipito-parietal) ones.

These functional alterations may be linked to atypical memory processes in ASD, including the pre-eminence of verbal over spatial information, impaired active maintenance in working memory, and preserved relational memory despite poor context processing in episodic memory.