Working Memory in ASD

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Working Memory

Working memory refers to an individual's ability to retain information in memory for a short period of time for a specific goal. It is thought of as a component of Executive_Functioning.There are many types of Working Memory (e.g. object, spatial, etc). One popular task for measuring spatial working memory is the Oculomotor Delayed Response task(ODR). The ODR task is a memroy-guided saccade task.1 More information on the Working Memory construct can be found here. There is some evidence supporting the heritability of spatial working memory, as implied by poorer performance by parents of ASD children on spatial working memory tasks.8

Working Memory and ASD

Working memory appears to be abnormal in those with ASD through studies which have used working memory tasks in ASD populations and the general population.3,4,5,6,7 ODR studies involving high-functioning autistic participants suggest that the ASD groups have reduced accuracy in memory guided saccades. Deficits are present in both adults with ASD and adolescents with ASD, but there appears to be improvement in performance from childhood to adolescence.1 One study found most of the circuitry involved in Working Memory intact in those with autism, including the insula, intraparietal sulcus, basal ganglia, thalamus, supramarginal gyrus, FEF, SEF, presupplementary motor area, ACC, precuneus, and cerebellum. The authors suggested that there may be a specific impairment involving the connectivity of prefrontal cortex with the posterior cortex. 2 There have also been evidence that working memory is not significantly different in those with ASD. The discrepancies may indicate compensatory mechanisms employed by participants to improve performance.1


Those with ASD demonstrate abnormal activation even if performance on working memory tasks is not significantly different from control groups. A study using an N-back working memory task with letter stimuli found that those with ASD show less activation in the left prefrontal regions, especially in the dorso-lateral prefrontal cortex, inferior frontal gyrus, and posterior pre-central sulcus. The authors suggested that verbal working memroy is related to the left prefrontal cortex while non-verbal working memroy is related to the right. Adults with ASD, they assert, may have been processing the letter stimuli as visual codes rather than phonological ones. A secondary study done by the same group using the same task except with facial stimuli found decreased activation in left prefrontal and right posterior temporal cortices. This implies that ASD participants viewed faces as objects rather than attaching emotional significance to the faces. However, functional connectivity analysis found lower connectivity in the frontal area and normal connectivity in the parietal cortices, which suggests that those with autism have a fundamentally different cortical network for working memory which makes extrapolation of findings to a normal population difficult.8

Cognitive tasks which assess Working Memory

  1. Oculomotor Delayed Response task
  2. Self-ordered Search task


1. O'Hearn K et. al. Neurodevelopment and executive function in autism.Dev Psychopathol. 2008 Fall;20(4):1103-32. PMID 18838033

2. Koshino H et. al. Functional connectivity in an fMRI working memory task in high-functioning autism.Neuroimage. 2005 Feb 1;24(3):810-21. PMID 15652316

3. Goldberg, M. C et. al. Deficits in the initiation of eye movements in the absence of a visual target in adolescents with high functioning autism.Neuropsychologia. 2002;40(12):2039-49. PMID 12208001

4. Luna B, et. al. Neocortical system abnormalities in autism: an fMRI study of spatial working memory.Neurology. 2002 Sep 24;59(6):834-40. PMID 12297562

5. Luna B et. al. Maturation of executive function in autism. Biol Psychiatry. 2007 Feb 15;61(4):474-81. PMID 16650833

6. Minshew NJ et. al. Oculomotor evidence for neocortical systems but not cerebellar dysfunction in autism.Neurology. 1999 Mar 23;52(5):917-22. PMID 10102406

7. Takarae Y et. al. Pursuit eye movement deficits in autism.Brain. 2004 Dec;127(Pt 12):2584-94 PMID 15509622

8.Greene CM et. al. Imaging the genetics of executive function.Biol Psychol. 2008 Sep;79(1):30-42. PMID 18178303