Memory can be thought of as the capacity of an organism to utilise past experience in order to direct current and future behaviour. Such a capacity entails the registering and recording – the encoding – of that experience in such a way as to enable its subsequent retrieval. Retrieval can be either voluntary or involuntary and the resultant information may or may not form part of conscious awareness. The processes of encoding and retrieval are the result of a range of psychological processes and are in turn influenced by other factors both psychological and physiological. In this respect, study of the patterning of memory processes and the factors that influence their operation can give clues to the wider psychological functioning of the individual. It is in this last respect that the study of memory can enhance our understanding of people with Autism Spectrum Disorder (ASD). ASD is not ‘caused by’ difficulties in memory, but the patterning of memory seen in individuals with ASD can provide clues to underlying cognitive and neuropsychological atypicalities as well as giving us a window onto their inner experiences of the world.

Preliminary remarks

Any discussion of memory in ASD must first emphasise the heterogeneous nature of the conditions that comprise the autism spectrum. An important aspect of this diversity is the distinction between ASD with accompanying intellectual disability (often referred to as ‘low-functioning ASD’ or LFA) and ASD without it (often termed ‘high-functioning ASD’ or HFA), a group that, as here defined, also includes individuals with Asperger's disorder.

Introduction

Memory difficulties are neither a prominent nor a defining feature of autism spectrum disorders (ASDs) yet these conditions are characterized by a consistent pattern of memory strengths and weaknesses. The earliest clinical reports of autistic memory often commented on good rote memory, and early experimental investigations mapped out a profile of spared and impaired areas of memory performance as well as highlighting the reduced role of structure and meaning in enhancing memory performance. The enlargement seen in the last two decades of our conception of autism to that of a spectrum of related conditions has been accompanied by research that has both confirmed many of these early findings in a wider diagnostic context and has also established distinct patterns of performance in other memory processes, such as an attenuated sense of self-awareness when recalling the personally experienced past and a diminished recall of incidentally encoded context. We now have sufficient understanding of memory in people with autism to enable some speculations about why in this group some memory processes should function typically and others not. Such speculations can also provide us with insights into how memory interacts with and depends on other psychological processes in ASD-specific ways, insights that in turn can illuminate a broader range of psychological functioning in this population.