Biomedical subjects

Jacob A Burack

Publications and source records attributed to Jacob A Burack.

10 recordsLinked to original sources

PubMed2006

Global-local visual processing in high functioning children with autism: structural vs. implicit task biases.

Global-local processing was examined in high-functioning children with autism and in groups of typically developing children. In experiment 1, the effects of structural bias were tested by comparing visual search that favored access to either local or global targets. The children with autism were not unusually sensitive to either level of visual structure. In experiment 2 a structural global bias was pitted against an implicit task bias favoring the local level. Children with autism were least sensitive to the structural global bias but showed greater sensitivity to the implicit task bias. This suggests that autism is associated with differences in the executive control processes used to guide attention to either the global or local level, and strategies may be more "data driven".

Attention↗

PubMed2006

Social perspective-taking skills in maltreated children and adolescents.

The primary goal of this study was to assess the ability of maltreated school-age children and adolescents to understand the thoughts, feelings, and points of view of others. Level of egocentrism and social perspective-taking coordination were assessed in a group of 49 maltreated and 49 demographically matched nonmaltreated children. Twenty-six elementary and 23 high school students in each group were individually interviewed and their responses to hypothetical interpersonal situations coded for egocentricity and level of perspective-taking ability. The findings revealed that maltreated children and adolescents were more egocentric and delayed in their social perspective-taking development than their nonmaltreated peers and that they reported lower levels of global self-worth. However, differences within the group of maltreated children and adolescents emerged with regard to negotiating novel relationships, as those with fewer internalizing or externalizing symptoms exhibited better skills in this area than their peers who displayed more symptoms.

Adolescent↗

PubMed2006

The development of change detection.

Changes to a scene often go unnoticed if the objects of the change are unattended, making change detection an index of where attention is focused during scene perception. We measured change detection in school-age children and young adults by repeatedly alternating two versions of an image. To provide an age-fair assessment we used a bimanual choice rather than open-ended verbal responses. The difference in detection speed and accuracy between 50-ms versus 250-ms blank screens between views indexed change detection in short-term visual memory independent of sensory and response processes. Younger children were significantly less efficient than older participants, especially when an object changed color or had a part deleted. Changes in object orientation were detected more readily. These results point to important differences in the perceptual reality of younger and older children.

Adolescent↗

PubMed2005

Eyes are special but not for everyone: the case of autism.

Current research indicates that human gaze direction is a special cue for shifting attention for one of two reasons: (1) it reflects social desires and intentions and (2) its basic perceptual features usually correspond to important events in the environment. This study, conducted with individuals with autism and with age- and IQ-matched typically developing individuals, dissociates these two often-confounded explanations and demonstrates that eyes appear to be special for typically developing individuals because of their social power, whereas gaze effects are mediated by feature correspondence among persons with autism.

Attention↗

PubMed2005

Voluntary orienting among children and adolescents with Down syndrome and MA-matched typically developing children.

A forced-choice reaction-time (RT) task was used to examine voluntary visual orienting among children and adolescents with trisomy 21 Down syndrome and typically developing children matched at an MA of approximately 5.6 years, an age when the development of orienting abilities reaches optimal adult-like efficiency. Both groups displayed faster reaction times (RTs) when the target location was cued correctly than when cued incorrectly under both short and long SOA conditions, indicating intact orienting among children with Down syndrome. This finding is further evidence that the efficiency of many of the primary components of attention among persons with Down syndrome is consistent with their developmental level.

Adolescent↗

PubMed2004

On mosaics and melting pots: conceptual considerations of comparison and matching strategies.

Conceptual and pragmatic issues relevant to the study of persons with autism are addressed within the context of comparison groups and matching strategies. We argue that no choice of comparison group or matching strategy is perfect, but rather needs to be determined by specific research objectives and theoretical questions. Thus, strategies can differ between studies in which the goal is to delineate developmental profiles and those in which the focus is the study of a specific aspect of functioning. We promote the notion of a "mosaic," rather than a "melting pot," approach to science in which researchers communicate conservative and precise interpretations of empirical findings.

Age Factors↗

PubMed2004

Intact covert orienting to peripheral cues among children with autism.

The focus of the present study was to examine covert orienting responses to peripheral flash cues among children with autism in a situation where attentional processes were taxed by the presence of distractors in the visual field. Fourteen children with autism (MA = 6-7 years) were compared to their MA-matched peers without autism on a forced choice RT covert orienting paradigm. The task conditions varied with regard to the target location, the validity of the cue, and the presence or absence of distractors. The results showed no group differences as both children with autism and their MA-matched peers showed similar effects of cue validity and distractors. These findings are inconsistent with the view that orienting is generally impaired in children with autism.

Adolescent↗

PubMed2003

Locally oriented perception with intact global processing among adolescents with high-functioning autism: evidence from multiple paradigms.

BACKGROUND: According to predictions from the Weak Central Coherence (WCC) theory for perceptual processing, persons with autism should display a tendency to focus on minute details rather than on a more general picture (Frith & Happé, 1994). However, the evidence for this theory is not consistent with findings of an enhanced detection of local targets (Plaisted, O'Riordan, & Baron-Cohen, 1998b; Plaisted, Swettenham, & Rees, 1999), but a typical global bias (Mottron, Burack, Stauder, & Robaey, 1999; Ozonoff, Strayer, McMahon, & Filloux, 1994). METHOD: Adolescents with high-functioning autism and CA- (approximately 15 years) and IQ- (approximately 105-110) matched typically developing adolescents were administered a series of global-local visual tasks, including a traditional task of hierarchical processing, three tasks of configural processing, and a disembedding task that involved rapid perceptual processing. RESULTS: No group differences were found on either the traditional task of hierarchical processing or on tasks of configural processing. However, group differences were found on the disembedding task as the search for embedded, in relation to isolated stimuli, was slower for the typically developing adolescents but similar for the participants with autism. CONCLUSIONS: These findings are consistent with other reports of superior performance in detecting embedded figures (Jolliffe & Baron-Cohen, 1997; Shah & Frith, 1983), but typical performance in global and configural processing (Mottron, Burack et al., 1999; Ozonoff et al., 1994) among persons with high-functioning autism. Thus, the notions of local bias and global impairment that are part of WCC may need to be reexamined.

Adolescent↗

PubMed2003

Developmental changes of autistic symptoms.

The study examined developmental changes in autistic symptoms retrospectively in a sample of 28 verbal children and adolescents with autism. Individuals with Asperger syndrome, PDD-NOS, and related medical conditions were not included in the study. We compared autistic symptoms present at the retrospective assessment and during the 4- to 5-year age period using the ADI-R. Our findings revealed a significant improvement in the three domains relevant for the diagnosis of autism, independent of age or IQ level. Improvement occurred in more symptoms from the social than the communication domain, and for more symptoms from the latter than the restricted interest and repetitive behavior domains. The finding that improvement was not linked to level of functioning and was found in individuals still positive for a diagnosis of autism suggests that improvement belongs to the 'natural history' of the handicap.

Adolescent↗

PubMed2002

Benefits and pitfalls in the merging of disciplines: the example of developmental psychopathology and the study of persons with autism.

Recent advances in the discipline of developmental psychopathology highlight the contributions of developmental thought to the study of persons with autism. This article briefly outlines primary developmental innovations in theory, methodology, and the interpretation of findings. Specifically. we discuss two sets of issues that arise from the general notion of developmental level. One set is relevant to the choice of persons that comprise the comparison group and the other to the various implications of the subjects' levels of functioning. In sum, we contend that researchers need to frame their empirical work within the context of developmental theory and methodology and interpret their findings accordingly. This will lead to scientifically compelling work and an increasingly heuristic approach to the study of persons with autism.

Attention Deficit Disorder with Hyperactivity↗