# Brain activation patterns of figurative language comprehension in individuals with autism spectrum disorder: an activation likelihood estimation meta-analysis

## TL;DR

This study finds that individuals with autism show reduced brain activity in specific regions when understanding figurative language, which may explain their language comprehension difficulties.

## Contribution

The study identifies consistent hypoactivation in the left STG and MTG in ASD during figurative language tasks using ALE meta-analysis.

## Key findings

- ASD and NCs both activate a core network including the bilateral STG and right insula during figurative language comprehension.
- ASD individuals show hypoactivation in the left STG and MTG compared to NCs.
- The hypoactivation suggests reduced semantic and socio-linguistic integration in ASD.

## Abstract

Individuals with Autism Spectrum Disorder (ASD) consistently exhibit difficulties in comprehending figurative language. While prior neuroimaging studies have identified discrepancies in brain activation between ASD individuals and neurotypical controls (NCs) during such tasks, the specific and consistent neural patterns underlying these deficits remain unclear.

We conducted an activation likelihood estimation (ALE) meta-analysis to identify consistent brain activation patterns associated with figurative language comprehension in ASD. A systematic literature search was performed across five databases (PubMed, Embase, Web of Science, CNKI, Wanfang) up to January 31, 2025. Six functional magnetic resonance imaging (fMRI) studies, comprising 95 individuals with ASD and 98 NCs, met the inclusion criteria.

The analysis revealed that during figurative language comprehension, both ASD and NCs consistently activated a core network involving the bilateral superior temporal gyrus (STG), transverse temporal gyrus, and right insula. A conjunction analysis confirmed the stability of these shared regions. Crucially, the meta-analysis of group differences (NCs > ASD) identified a significant cluster of hypoactivation in the ASD group within the left STG and middle temporal gyrus (MTG). No significant hyperactivation was found in the ASD group compared to NCs.

This meta-analysis demonstrates that while individuals with ASD recruit typical language networks during figurative language comprehension, they exhibit a consistent pattern of reduced neural recruitment in the left STG and MTG. This hypoactivation may reflect a dual deficit encompassing reduced efficiency in semantic access/integration and impaired socio-linguistic integration, providing a neurobiological substrate for the pragmatic language difficulties characteristic of ASD.

https://www.crd.york.ac.uk/PROSPERO/view/CRD42023467185, CRD42023467185.