The Episodic Memory Profile in Autism Spectrum Disorder: A Bayesian Meta-Analysis

Area of Science:

• Neuroscience
• Psychology
• Developmental Disorders

Background:

• Autism spectrum disorder (ASD) is often associated with episodic memory impairments, but existing research presents conflicting findings.
• Understanding these memory differences is crucial for targeted interventions and support.

Purpose of the Study:

• To quantitatively synthesize episodic memory differences between individuals with ASD and typically developing (TD) controls.
• To investigate how test modality, delay, retrieval demands, and sensory modality influence these memory differences.

Main Methods:

• Multilevel Bayesian meta-analysis and meta-regression were employed.
• Data from 113 empirical articles, comprising 338 effect sizes and 5,632 participants (2,777 ASD, 2,855 TD), were analyzed.

Main Results:

• Individuals with ASD showed larger memory deficits in recall (g = -0.52) compared to recognition (g = -0.25).
• Memory deficits varied by test modality, with smaller effects for words and pictures, and larger effects for sentences, stories, and staged events.
• Effect sizes were largest for staged events (g = -0.75) and smallest for word lists (g = -0.28).

Conclusions:

• ASD is associated with a small to medium reduction in episodic memory test performance compared to TD individuals.
• The extent of memory impairment in ASD is influenced by specific testing parameters, highlighting the need for nuanced interpretation of memory assessments.