Short-term memory in autism spectrum disorder.

Three experiments examined verbal short-term memory in comparison and autism spectrum disorder (ASD) participants. Experiment 1 involved forward and backward digit recall. Experiment 2 used a standard immediate serial recall task where, contrary to the digit-span task, items (words) were not repeated from list to list. Hence, this task called more heavily on item memory. Experiment 3 tested short-term order memory with an order recognition test: Each word list was repeated with or without the position of 2 adjacent items swapped. The ASD group showed poorer performance in all 3 experiments. Experiments 1 and 2 showed that group differences were due to memory for the order of the items, not to memory for the items themselves. Confirming these findings, the results of Experiment 3 showed that the ASD group had more difficulty detecting a change in the temporal sequence of the items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory functioning in children and adolescents with autism.

Objective: Memory functioning in children and adolescents ages 5–19 with autism (n = 50) and typically developing controls (n = 36) was assessed using a clinical assessment battery, the Test of Memory and Learning (TOMAL). Method: Participant groups were statistically comparable in age, nonverbal IQ, handedness, and head circumference, and were administered the TOMAL. Results: Test performance on the TOMAL demonstrated broad differences in memory functioning in the autism group, across multiple task formats, including verbal and nonverbal, immediate and delayed, attention and concentration, sequential recall, free recall, associative recall, and multiple-trial learning memory. All index and nearly all subtest differences remained significant even after comparing a subset of the autism group (n = 36) and controls that were matched for verbal IQ (p > .05). However, retention of previously remembered information after a delay was similar in autism and controls. Conclusions: These findings indicate that performance on measures of episodic memory is broadly reduced in autism, and support the conclusion that information encoding and organization, possibly due to inefficient cognitive processing strategies, rather than storage and retrieval, are the primary factors that limit memory performance in autism. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Episodic memory and episodic future thinking in adults with autism.

The ability to remember past experiences (episodic memory) is thought to be related to the ability to imagine possible future experiences (episodic future thinking). Although previous research has established that individuals with autism spectrum disorder (ASD) have diminished episodic memory, episodic future thinking has not previously been investigated within this population. In the present study, high-functioning adults with ASD were compared to closely matched typical adults on a task requiring participants to report a series of events that happened to them in the past and a series of events that might happen to them in the future. For each event described, participants completed two modified Memory Characteristics Questionnaire items to assess self-reported phenomenal qualities associated with remembering and imagining, including self-perspective and degree of autonoetic awareness. Participants also completed letter, category, and ideational fluency tasks. Results indicated that participants with ASD recalled/imagined significantly fewer specific events than did comparison participants and that participants with ASD demonstrated impaired episodic memory and episodic future thinking. In line with this finding, participants with ASD were less likely than comparison participants to report taking a field (first-person) perspective and were more likely to report taking an observer (third-person) perspective during retrieval of past events (but not during simulation of future events), highlighting that they were less likely to mentally reexperience past events from their own point of view. There were no group differences in self-reported levels of autonoetic awareness or fluency task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The development of prospective memory in typically developing children.

Objective: This study aimed to use specifically designed tasks to capture time-based, activity-based, and event-based prospective memory (PM) performance in typically developing school-age children. Method: Two PM tasks (Fishing Game & Happy Week) were used to examine the developmental patterns of PM in these children. Retrospective memory (RM) was also examined in these tasks. A total of 120 children aged between 7 and 12 years (10 girls and 10 boys in each age band) were recruited. Tests of working memory, inhibition, and IQ were also administered. Results: The age effect on PM accuracy was significant, with improvements identified between ages 7 to 8 and 10 to 11 years. For both tasks, performance on the time-based PM task was significantly poorer than that on the event-based PM task, which in turn was significantly poorer than that on the activity-based PM task. In terms of errors, results indicated that while errors associated with the PM component of the tasks decreased with age, errors associated with the RM component showed an inverted-U shape. The different patterns of errors suggest qualitative as well as quantitative differences in PM development in children. Finally, IQ, working memory, and inhibition were found to relate to PM when age was partialed out. Conclusions: Results of the study highlight the importance of contextual cues, such as activities and events, for prospective remembering in children. In addition, they have provided a general picture of PM development in school-age children and have implications for educators and parents. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The structure of intelligence in children and adults with high functioning autism.

Confirmatory factor analyses of the commonly used 11 subtests of the Wechsler child and adult intelligence scales were accomplished for 137 children and 117 adults with high functioning autism (HFA) and for comparable age groups from the standardization samples contained in the Wechsler manuals. The objectives were to determine whether the structure of intelligence in HFA groups was similar to that found in the normative samples, and whether a separate social context factor would emerge that was unique to HFA. Four-factor models incorporating a Social Context factor provided the best fit in both the autism and normative samples, but the subtest intercorrelations were generally lower in the autism samples. Findings suggest similar organization of cognitive abilities in HFA, but with the possibility of underconnectivity or reduced communication among brain regions in autism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Executive function in individuals with subthreshold autism traits.

Objective: Recent research has documented increased psychosocial difficulties in individuals who report higher-than-typical autistic traits but without an Autism Spectrum Disorder (ASD) diagnosis. Less is known, however, regarding the cognitive profile of individuals with subthreshold autism symptomatology. The objective of the present study was to provide additional insight into this issue and examine whether young adults who report higher degrees of autism traits also report experiencing increased difficulties with executive control. Method: The Behavior Rating Inventory of Executive Function was utilized to evaluate behavioral aspects of executive functioning in 66 and 28 individuals who endorsed high and low subthreshold levels of autism symptomatology, respectively. Results: After accounting for Attention Deficit/Hyperactivity Disorder (ADHD) symptomatology at both the group and individual participant levels, we found that autism traits continued to explain a significant amount of variance in participants' overall level of executive function (Global Executive Composite) as well as within most individual executive domains. Interestingly, the high and low trait groups did not differ on the inhibitory control and organization of materials scales, areas of functioning that appears to be largely spared in individuals with ASD as well. Conclusions: Findings from the present study are consistent with past research linking ASD and executive control impairment. In addition, ASD and ADHD traits were associated with unique contributions to the executive control profile of individuals with subthreshold autism symptomatology. This finding underscores the importance of accounting for ADHD symptomatology in studying ASD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Superior visual search in autism.

Children with a diagnosis of autism and normally developing children, matched for age and general ability, were tested on a series of visual search tasks in 2 separate experiments. The children with autism performed better than the normally developing children on difficult visual search tasks,. This result occurred regardless of whether the target was uniquely defined by a single feature or a conjunction of features, as long as ceiling effects did not mask the difference. Superior visual search performance in autism can be seen as analogous to other reports of enhanced unique item detection in autism. Unique item detection in autism is discussed in the light of mechanisms proposed to be involved in normal visual search performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Links between theory of mind and executive function in young children with autism: Clues to developmental primacy.

There has been much theoretical discussion of a functional link between theory of mind (ToM) and executive function (EF) in autism. This study sought to establish the relationship between ToM and EF in young children with autism (M = 5 years, 6 months) and to examine issues of developmental primacy. Thirty children with autism and 40 typically developing children, matched on age and ability, were assessed on a battery of tasks measuring ToM (1st- and 2nd-order false belief) and components of EF (planning, set shifting, inhibition). A significant correlation emerged between ToM and EF variables in the autism group, independent of age and ability, while ToM and higher order planning ability remained significantly related in the comparison group. Examination of the pattern of ToM-EF impairments in the autism group revealed dissociations in 1 direction only: impaired ToM with intact EF. These findings support the view that EF may be 1 important factor in the advancement of ToM understanding in autism. The theoretical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word learning in children with autism spectrum disorders.

Autism spectrum disorders (ASD) have been gaining attention, partly as an example of unusual developmental trajectories related to early neurobiological differences. The present investigation addressed the process of learning new words to explore mechanisms of language delay and impairment. The sample included 21 typically developing toddlers matched on expressive vocabulary with 21 young children with ASD. Two tasks were administered to teach children a new word and were supplemented by cognitive and diagnostic measures. In most analyses, there were no group differences in performance. Children with ASD did not consistently make mapping errors, even in word learning situations that required the use of social information. These findings indicate that some children with ASD, in developmentally appropriate tasks, are able to use information from social interactions to guide word–object mappings. This result has important implications for understanding of how children with ASD learn language. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selectivity of executive function deficits in mild cognitive impairment.

Impairment in executive cognition (EC) is now recognized as relatively common among older persons with mild cognitive impairment (MCI) and may be predictive of the development of dementia. However, both MCI and executive functioning are broad and heterogeneous constructs. The present study sought to determine whether impairments in specific domains of EC are associated with specific subtypes of MCI. MCI patients (n = 124) were divided into 4 subgroups (amnestic vs. nonamnestic, and single- vs. multiple-domain) on the basis of their performance of widely used neuropsychological screening tests. These patients and 68 normal older persons were administered 18 clinical and experimental tests of executive function. Principal components analysis suggested 2 highly reliable EC components, planning/problem solving and working memory, and a less reliable 3rd component, judgment. Planning/problem solving and working memory, but not judgment, were impaired among the MCI patients. This was true even among those with “pure amnestic” MCI, the least impaired group overall. Multiple-domain MCI patients had more severe impairments in planning/problem solving and working memory than single-domain patients, leading to the supposition that they, not pure amnestic MCIs, are at highest risk of imminent dementia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Patterns of growth in verbal abilities among children with autism spectrum disorder.

Verbal skills were assessed at approximately ages 2, 3, 5, and 9 years for 206 children with a clinical diagnosis of autism (n = 98), pervasive developmental disorders-not otherwise specified (PDD-NOS; n = 58), or nonspectrum developmental disabilities (n = 50). Growth curve analyses were used to analyze verbal skills trajectories over time. Nonverbal IQ and joint attention emerged as strong positive predictors of verbal outcome. The gap between the autism and other 2 groups widened with time as the latter improved at a higher rate. However, there was considerable variability within diagnostic groups. Children with autism most at risk for more serious language impairments later in life can be identified with considerable accuracy at a very young age, while improvement can range from minimal to dramatic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for selective inhibitory impairment in individuals with autism spectrum disorder.

Objective: The social and communicative challenges faced by individuals with autism spectrum disorder (ASD) are often compounded by additional difficulties with executive function. It remains unclear, however, to what the extent individuals with ASD experienced impairment in inhibitory control. The objective of the present study was to assess the three main subtypes of executive inhibitory control within a single ASD sample thus providing new insight into the unique ASD-related pattern of sparing and impairment observed across different aspects of inhibitory control. Method: A sample of 28 children with ASD (mean age = 13.1 years) and a comparison group of 49 neurologically uncompromised children (mean age = 13.3 years) participated. A prepotent response inhibition task, a flanker visual filtering task, and a proactive interference memory task were used to evaluate prepotent response inhibition, resistance to distracter interference, and resistance to proactive interference, respectively. Results: After accounting for individual differences in noninhibition abilities (e.g., processing speed) and overall level of functioning, there was no evidence of group-related differences in inhibitory performance on the prepotent response inhibition test or proactive interference test. ASD-related impairments in inhibitory control were evident, however, on the flanker visual filtering task. Conclusions: Taken together, the present findings indicate that ASD is associated with impairments in some, but not all, aspects of inhibitory control. Individuals with ASD appear to have difficulty ignoring distracting visual information, but prepotent response inhibition and resistance to proactive interference are relatively intact. The current findings also provide support for a multitype model of inhibitory control. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Early patterns of verbal memory impairment in children treated for medulloblastoma.

Children treated for medulloblastoma demonstrate a variety of cognitive deficits in addition to white matter and hippocampal neuropathology. This study examined 40 children treated for medulloblastoma as compared with 40 demographically matched controls on the California Verbal Learning Test-Children's Version (D. C. Delis, J. H. Kramer, E. Kaplan, & B. A. Ober, 1994). Results revealed significantly poorer performance on indices of word recall in the patient group as compared with the controls in addition to milder but still significantly poorer recognition memory. These findings suggest that children treated for medulloblastoma demonstrate a mixed profile of memory impairment consisting of both retrieval and recognition deficits. Implications of these findings for understanding neurobehavioral sequelae within pediatric medulloblastoma populations and for designing educational and remediation strategies to be used with these children are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relative risk and timing of divorce in families of children with an autism spectrum disorder.

We compared the occurrence and timing of divorce in 391 parents of children with an autism spectrum disorder (ASD) and a matched representative sample of parents of children without disabilities using a survival analysis. Parents of children with an ASD had a higher rate of divorce than the comparison group (23.5% vs. 13.8%). The rate of divorce remained high throughout the son's or daughter's childhood, adolescence, and early adulthood for parents of children with an ASD, whereas it decreased following the son's or daughter's childhood (after about age 8 years) in the comparison group. Younger maternal age when the child with ASD was born and having the child born later in the birth order were positively predictive of divorce for parents of children with an ASD. Findings have implications for interventions focused on ameliorating ongoing and long-term marital strains for parents of children with an ASD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Understanding of emotional experience in autism: Insights from the personal accounts of high-functioning children with autism.

In this study, the authors investigate emotional understanding in autism through a discourse analytic framework to provide a window into children's strategies for interpreting emotional versus nonemotional encounters and consider the implications for the mechanisms underlying emotional understanding in typical development. Accounts were analyzed for thematic content and discourse structure. Whereas high-functioning children with autism were able to discuss contextually appropriate accounts of simple emotions, their strategies for interpreting all types of emotional (but not nonemotional) experiences differed from those used by typically developing children. High-functioning children with autism were less inclined to organize their emotional accounts in personalized causal-explanatory frameworks and displayed a tendency to describe visually salient elements of experiences seldom observed among comparison children. Findings suggest that children with autism possess less coherent representations of emotional experiences and use alternative strategies for interpreting emotionally evocative encounters. Discussion focuses on the significance of these findings for informing the nature of emotional dysfunction in autism as well as implications for theories of emotional understanding in typical development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Music training improves verbal but not visual memory: Cross-sectional and longitudinal explorations in children.

The hypothesis that music training can improve verbal memory was tested in children. The results showed that children with music training demonstrated better verbal but not visual memory than did their counterparts without such training. When these children were followed up after a year, those who had begun or continued music training demonstrated significant verbal memory improvement. Students who discontinued the training did not show any improvement. Contrary to the differences in verbal memory between the groups, their changes in visual memory were not significantly different. Consistent with previous findings for adults (A. S. Chan, Y. Ho, & M. Cheung, 1998), the results suggest that music training systematically affects memory processing in accordance with possible neuroanatomical modifications in the left temporal lobe. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Goal-directed memory: The role of cognitive control in older adults' emotional memory.

The present study revealed that older adults recruit cognitive control processes to strengthen positive and diminish negative information in memory. In Experiment 1, older adults engaged in more elaborative processing when retrieving positive memories than they did when retrieving negative memories. In Experiment 2, older adults who did well on tasks involving cognitive control were more likely than those doing poorly to favor positive pictures in memory. In Experiment 3, older adults who were distracted during memory encoding no longer favored positive over negative pictures in their later recall, revealing that older adults use cognitive resources to implement emotional goals during encoding. In contrast, younger adults showed no signs of using cognitive control to make their memories more positive, indicating that, for them, emotion regulation goals are not chronically activated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Executive function in parents of children with autism

BACKGROUND: Previous studies have shown that individuals with autism show impaired performance on tests of executive function (Ozonoff et al. 1991, 1993; Hughes & Russell, 1993; Hughes et al. 1994). There is also strong evidence for genetic involvement in autism (see Rutter, 1991 for review). If executive dysfunction is a core impairment in autism, then similar impairments are hypothesized to exist in a subtler form among the parents of autistic children. METHODS: Forty parents of autistic children were compared with 40 parents of learning disabled children and 36 adults from unaffected families on three computerized tests of executive function. These tasks tapped attentional-shifting skills, visuospatial planning and working memory. Participants also received a computerized control test of spatial memory-span. In addition, the interviewer's initial impressions of family members were coded using a new 33-item questionnaire. RESULTS: A significant proportion of parents of autistic children (especially fathers) showed impaired executive function. By contrast, parents did as well as both comparison groups on a control test of spatial span, and on other 'non-executive' measures from the tasks, indicating that the autism group were as able and motivated as comparison groups. Interestingly, impairment of executive function was significantly correlated with the interviewer's pre-test impression of social abnormality among parents of autistic children. CONCLUSIONS: The hypothesis that a significant proportion of parents of autistic children show impaired executive function was supported. Parents showed good memory ability, but relatively poor planning skills and attentional flexibility. The extent to which this is an inherent trait in family members, rather than a reflection of the difficulties involved in caring for an autistic child, remains to be examined.     

The complexities of complex span: Explaining individual differences in working memory in children and adults.

Two studies are presented that investigated the constraints underlying working memory performance in children and adults. In each case, independent measures of processing efficiency and storage capacity are assessed to determine their relative importance in predicting performance on complex span tasks, which measure working memory capacity. Results show that complex span performance was independently constrained by individual differences in dornain-general processing efficiency and domain-specific storage capacity. Residual variance, which may reflect the ability to coordinate storage and processing, also predicted academic achievement. These results challenge the view that complex span taps, a limited-capacity resource pool shared between processing and storage operations. Rather, they are consistent with a multiple-component model in which separate resource pools support the processing and storage functions of working memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Daily stress, coping, and well-being in parents of children with autism: A multilevel modeling approach.

This study used a repeated daily measurement design to examine the direct and moderating effects of coping on daily psychological distress and well-being in parents of children with Autism Spectrum Disorders (ASD). Twice weekly over a 12-week period, 93 parents provided reports of their daily stress, coping responses, and end-of-day mood. Multilevel modeling analyses identified 5 coping responses (e.g., seeking support, positive reframing) that predicted increased daily positive mood and 4 (e.g., escape, withdrawal) that were associated with decreased positive mood. Similarly, 2 coping responses were associated with decreased daily negative mood and 5 predicted increased negative mood. The moderating effects of gender and the 11 coping responses were also examined. Gender did not moderate the daily coping?mood relationship, however 3 coping responses (emotional regulation, social support, and worrying) were found to moderate the daily stress?mood relationship. Additionally, ASD symptomatology, and time since an ASD diagnosis were not found to predict daily parental mood. This study is perhaps the first to identify coping responses that enhance daily well-being and mitigate daily distress in parents of children with ASD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)