Memory for Self-Performed Actions in Individuals with Asperger Syndrome

Tiziana Zalla,Daniele Nico,Pauline Chaste,Elena Daprati,Anca-Maria Sav,Marion Leboyer,Mark W Greenlee

doi:10.1371/journal.pone.0013370

Abstract

Memory for action is enhanced if individuals are allowed to perform the corresponding movements, compared to when they simply listen to them (enactment effect). Previous studies have shown that individuals with Autism Spectrum Disorders (ASD) have difficulties with processes involving the self, such as autobiographical memories and self performed actions. The present study aimed at assessing memory for action in Asperger Syndrome (AS). We investigated whether adults with AS would benefit from the enactment effect when recalling a list of previously performed items vs. items that were only visually and verbally experienced through three experimental tasks (Free Recall, Old/New Recognition and Source Memory). The results showed that while performance on Recognition and Source Memory tasks was preserved in individuals with AS, the enactment effect for self-performed actions was not consistently present, as revealed by the lower number of performed actions being recalled on the Free Recall test, as compared to adults with typical development. Subtle difficulties in encoding specific motor and proprioceptive signals during action execution in individuals with AS might affect retrieval of relevant personal episodic information. These disturbances might be associated to an impaired action monitoring system.

Highlights

Autism spectrum disorders (ASD) are pervasive developmental disorders characterized by abnormal social interaction, verbal and non-verbal communication problems and restricted interests
The present study aimed at assessing whether adults with Asperger Syndrome (AS) would benefit from the enactment effect when recalling a list of previously enacted items vs. items that were only visually and verbally experienced. The presence of this memory facilitation was tested through a Free Recall test and an Old/New Recognition task. We investigated whether these individuals can overtly distinguish self-performed actions from actions performed by others through a Source Memory Recognition task
The interaction was due to participants with AS recalling significantly fewer enacted items compared to comparison participants, whereas the proportion of the observed items was comparable in the two groups (Figure 2)

Summary

Introduction

Autism spectrum disorders (ASD) are pervasive developmental disorders characterized by abnormal social interaction, verbal and non-verbal communication problems and restricted interests. Within the domain of ASD, High functioning autism (HFA) commonly refers to individuals meeting criteria for autism with normal intellectual functioning and a history of speech and language delay. Those at the higher-functioning end of the HFA group, sometimes diagnosed with Asperger Syndrome (AS) [1,2] show no evidence of delayed language function and their intellectual abilities fall within the normal range. As with other individuals with ASD, the clinical features of HFA and AS include troubles forming friendships, difficulties with social cognition, inappropriate social interactions, poor communication, restricted interests and diminished capacity for empathy. Individuals with AS can often solve first-order (e.g. ‘‘Sally thinks it’s x, when really it’s y’’) and second-order false beliefs tests (e.g. ‘‘Sally thinks Mary thinks x, but both Sally and Mary are wrong’’) [4,5], they might fail more ‘advanced’ ToM tasks, based on detection of sarcasm, irony or bluff [6] or on recognition of Faux Pas [7,8]

Results

Discussion

Conclusion