Seeing it differently: visual processing in autism

Several recent behavioral and neuroimaging studies have documented an impairment in face processing in individuals with Autism Spectrum Disorder (ASD). It remains unknown, however, what underlying mechanism gives rise to this face processing difficulty. One theory suggests that the difficulty derives from a pervasive problem in social interaction and/or motivation. An alternative view proposes that the face-processing problem is not entirely social in nature and that a visual perceptual impairment might also contribute. The focus of this review is on this latter, perceptual perspective, documenting the psychological and neural alterations that might account for the face processing impairment. The available evidence suggests that perceptual alterations are present in ASD, independent of social function.     

Amygdalectomy and responsiveness to novelty in rhesus monkeys (Macaca mulatta): generality and individual consistency of effects

Rhesus monkeys (Macaca mulatta) with bilateral ibotenic acid-produced lesions of the amygdala were compared with controls in several novel situations, including exposures to metal objects, toy animals, and a person. Early in testing, the monkeys with lesions showed reduced inhibitions on responsiveness compared with controls. With continuing exposures, differences between groups diminished sharply as inhibitions waned in the controls. This outcome is consistent with the hypothesis that the amygdala mediates caution in initial reactions to ambiguous or threatening novel situations, which, in the absence of adverse consequences, diminishes with repetition. Consistency of individual responsiveness across different situations, including pairing with other monkeys, was substantial in lesioned and normal monkeys, suggesting that stable qualities of temperament influenced the results in both groups.     

Differential developmental trajectories for egocentric, environmental and intrinsic frames of reference in spatial memory

We studied the development of spatial frames of reference in children aged 3-6 years, who retrieved hidden toys from an array of identical containers bordered by landmarks under four conditions. By moving the child and/or the array between presentation and test, we varied the consistency of the hidden toy with (i) the body, and (ii) the testing room. The toy's position always remained consistent with (iii) the array and bordering landmarks. We found separate, additive performance advantages for consistency with body and room. These effects were already present at 3 years. A striking finding was that the room effect, which implies allocentric representations of the room and/or egocentric representations updated by self-motion, was much stronger in the youngest children than the body effect, which implies purely egocentric representations. Children as young as 3 years therefore had, and greatly favoured, spatial representations that were not purely egocentric. Viewpoint-independent recall based only on the array and bordering landmarks emerged at 5 years. There was no evidence that this later-developing ability, which implies object-referenced (intrinsic) representations, depended on verbal encodings. These findings indicate that core components of adult spatial competence, including parallel egocentric and nonegocentric representations of space, are present as early as 3 years. These are supplemented by later-developing object-referenced representations.     

A novel view of between-categories contrast and within-category assimilation

This research manipulated the portion of a category distribution that is misclassified by the optimal classifier and investigated the impact on assessments of category attributes. Three separate studies manipulated the direction of overlap, the extent of overlap, and the relative base rate of the comparison category. All 3 studies produced large between-categories contrast and within-category assimilation. As expected, these effects were enhanced in conditions in which the optimal classifier misclassified a larger portion of the target category. Study 4 demonstrated that intercategory overlap in the absence of overt classification does not produce contrast and assimilation. Ironically, optimizing categorization accuracy can produce highly inaccurate beliefs about category attributes.     

Parents' and teachers' concordance with children's self-ratings of suicidality: findings from a high-risk sample

This study examined concordance between adult and child reports of child suicidality using a sample of 1,046 8-year-old children at risk for, or having experienced, maltreatment. Concordance was low with both caregivers and teachers. For children reporting no suicidality, caregiver-child agreement was associated with few transitions in caregiver and low social withdrawal and aggression, and teacher-child agreement was associated with non-White ethnicity, good academic performance, and low thought problems. For children reporting suicidality, care-giver-child agreement was associated with perceptions of child mental health needs, aggression, and somatic complaints, and teacher-child agreement was associated with thought problems.     

Online Story Comprehension among Children with ADHD: Which Core Deficits are Involved?

Children with ADHD have difficulty understanding causal connections and goal plans within stories. This study examined mediators of group differences in story narrations between children ages 7-9 with and without ADHD, including as potential mediators both the core deficits of ADHD (i.e., inattention, disinhibition, planning/working memory) as well measures of phonological processing and verbal skills. Forty-nine children with ADHD and 67 non-referred children narrated a wordless book and completed tasks assessing the core deficits of ADHD, phonological processing, and verbal skills. Results revealed that, although no shorter than those of non-referred children, the narratives of children with ADHD contained fewer elements relating to the story's causal structure and goal plan. Deficits in sustained attention accounted for the most variance in these differences. Results have implications for understanding and ameliorating the academic problems experienced by children with ADHD.     

Individual differences in children's memory and reading comprehension: an investigation of semantic and inhibitory deficits

Three experiments compared the verbal memory skills of children with poor reading comprehension with that of same-age good comprehenders. The aims were to determine if semantic and/or inhibitory deficits explained comprehenders' problems on measures of verbal short-term memory and verbal working memory. In Experiment 1 there were no group differences on word- and number-based measures of short-term storage and no evidence that semantic knowledge mediated word recall. In Experiment 2 poor comprehenders were impaired on word- and number-based assessments of working memory, the greatest deficit found on the word-based task. Error analysis of both word-based tasks revealed that poor comprehenders were more likely to recall items that should have been inhibited than were good comprehenders. Experiment 3 extended this finding: Poor comprehenders were less able to inhibit information that was no longer relevant. Together, these findings suggest that individual differences in inhibitory processing influence the ability to regulate the contents of working memory, which may contribute to the differential memory performance of good and poor comprehenders.     

Disgust vulnerability and symptoms of contamination-based OCD: descriptive tests of incremental specificity

The present investigation examines the incremental association between disgust propensity and sensitivity and contamination-based obsessive-compulsive disorder (OCD) symptoms. Structural equation modeling in Study 1 indicated that general disgust was related to contamination fear even when controlling for negative affect in a nonclinical sample. Evidence was also found for a model in which the effect of negative affect on contamination fear is mediated by general disgust. Study 1 also showed that both disgust sensitivity and disgust propensity uniquely predicted contamination fear when controlling for negative affect. Growth curve analyses in Study 2 indicated that higher baseline contamination fear is associated with less reduction in contamination fear over a 6-week period as disgust sensitivity increases even when controlling for negative affect. Lastly, disgust propensity was associated with concurrent levels of excessive washing symptoms among patients with OCD in Study 3 when controlling for depression. Implications of these findings from nonclinical, analogue, and clinical samples for future research on the specificity of disgust-related vulnerabilities in the etiology of contamination concerns in OCD are discussed.     

Efficacy of self-administered treatments for pathological academic worry: A randomized controlled trial

Research on treatments for reducing pathological worry is limited. In particular, academic worry is a common theme in generalized anxiety disorder (GAD) samples as well as non-clinical student samples. Given the high cost of anxiety disorders to society, research is needed to examine the efficacy of self-administered treatments designed to reduce pathological worry. The primary goal of this study was to investigate the benefits of three self-administered interventions for reducing academic worry. College students (N = 113) experiencing clinically significant academic worry were randomized to either: (a) worry exposure (WE); (b) expressive writing (EW); (c) relaxation consisting of pulsed audio-photic stimulation (APS); or (d) waitlist control (WLC). Participants were instructed to practice their interventions three times per week for one month and completed home practice logs online to track treatment adherence. Academic worry, general anxiety, and perceived stress were assessed at baseline and post-treatment. Academic worry and general anxiety were also assessed at a three-month follow-up. Those assigned to the WE and APS conditions showed significant improvement relative to EW and WLC at post-treatment. All treatment conditions showed continued improvement by follow-up, with no between-group differences. Treatment and public health implications are discussed.     

Intrusive imagery in severe health anxiety: Prevalence, nature and links with memories and maintenance cycles

Increased understanding of the nature and role of intrusive imagery has contributed to the development of effective treatment protocols for some anxiety disorders. However, intrusive imagery in severe health anxiety (hypochondriasis) has been comparatively neglected. Hence, the current study investigates the prevalence, nature and content of intrusive imagery in 55 patients who met DSM-IV-TR (APA, 2000) criteria for the diagnosis of hypochondriasis. A semi-structured interview was used to assess the prevalence, nature and possible role of intrusive imagery in this disorder. Over 78% of participants reported experiencing recurrent, distressing intrusive images, the majority (72%) of which either were a memory of an earlier event or were strongly associated with a memory. The images tended to be future orientated, and were reliably categorised into four themes: i) being told ‘the bad news’ that you have a serious/life threatening-illness (6.9%), ii) suffering from a serious or life-threatening illness (34.5%), iii) death and dying due to illness (22.4%) and iv) impact of own death or serious illness on loved ones (36.2%). Participants reported responding to experiencing intrusive images by engaging in avoidance, checking, reassurance seeking, distraction and rumination. Potential treatment implications and links to maintenance cycles are considered.