This is the accepted version of the paper.This version of the publication may differ from the final published version. Behavioral evidence concerning memory in high-functioning forms of autism (HFA) and in moderately low-functioning autism (M-LFA) is reviewed and compared. Findings on M-LFA are sparse. However, it is provisionally concluded that memory profiles in HFA and M-LFA (relative to ability-matched controls) are similar, but that declarative memory impairments are more extensive in M-LFA than in HFA. Specifically, both groups have diminished memory for emotion-or person-related stimuli. Regarding memory for non-social stimuli, both groups probably have mental-age appropriate nondeclarative memory; and within declarative memory, both groups have mental-age appropriate immediate free recall of within-span or supra-span lists of unrelated items, as well as cued recall and paired associate learning. By contrast, recognition is largely unimpaired in HFA but moderately impaired in M-LFA; and free recall of meaningful or structured stimuli is moderately impaired in HFA but more severely impaired in M-LFA. Permanent repository link:Theoretical explanations of data on declarative memory in HFA identify problems in the integrative processing, or the consolidation and storage, of complex stimuli; or a specific problem of recollection. Proposed neural substrates include the following: disconnectivity of primary sensory and association areas; dysfunctions of medial prefrontal cortex, hippocampus or posterior parietal lobe; or combinations of these associated with neural disconnectivity.Hypothetically, perirhinal dysfunction might explain the more extensive declarative memory impairments in M-LFA. Foreseeable consequences of uneven memory abilities in HFA and M-LFA are outlined, including possible effects on language and learning in M-LFA. Finally, priorities for future research are identified, highlighting the urgent need for research on memory in lower-functioning individuals. "It is impossible to separate the study of memory from that of autism" DeLong (2003, p. 741) Memory and learning are inseparable, and congenital or early acquired anomalies of memory will affect how and what an individual learns, which will in turn affect the course and outcomes of behavioral and brain development, including the ways in which an individual experiences and responds to the external world.It is well established that certain memory impairments are present in all individuals with autistic spectrum disorder (ASD) (Boucher & Bowler, 2008). It is less clear, however, what differences there may be in the range and severity of memory impairments across the spectrum, from linguistically and intellectually able individuals with Asperger syndrome; through those high-functioning individuals in whom language is initially delayed but subsequently normalizes; through those with persistent, mild to moderate language impairment, usually accompanied by intellectual disability (ID); to the substantial subgroup of individuals with ASD who have ...

We hypothesise that of the two processes underlying declarative memory, recollection is impaired in high-functioning autism (HFA) whereas recollection and familiarity are impaired in low-functioning autism (LFA). Testing these hypotheses necessitates assessing recollection and familiarity separately. However, this is difficult, because both processes contribute to performance on standard memory tests. Moreover, tests must be suitable for use with young or intellectually disabled participants. This study aimed to develop tests of recollection and familiarity separately, and to make preliminary tests of our hypotheses. We developed a temporal source memory task to assess recollection in LFA, and a shape recognition task to assess familiarity and an action recall task assessing recollection in HFA. The methods and implications of the results are discussed.

No abstract

The hypothesis that a pervasive impairment of declarative memory contributes to language impairment in low functioning autism (LFA) was tested. Participants with LFA, high functioning autism (HFA), intellectual disability (ID) without autism, and typical development (TD) were given two recognition tests and four tests of lexical understanding. It was predicted that recognition would be impaired in the LFA group relative to the HFA and TD groups but not the ID group, and that recognition would correlate with lexical knowledge in the LFA group but none of the other groups. These predictions were supported except that the HFA group performed more similarly to the LFA group than expected, a finding interpreted in terms of selectively impaired episodic memory.