Biomedical subjects

Peter K Isquith

Publications and source records attributed to Peter K Isquith.

9 recordsLinked to original sources

PubMed2006

Self- and informant reports of executive function on the BRIEF-A in MCI and older adults with cognitive complaints.

Amnestic mild cognitive impairment (MCI) is characterized by impaired episodic memory, although subtle executive problems have been noted on neuropsychological tests. Recent research also has described a group of healthy, non-depressed older adults with significant cognitive complaints (CC) but normal performance on neuropsychological testing. These individuals show structural and functional brain changes intermediate between those seen in MCI and healthy older adults without such complaints (HC). We evaluated executive functions in MCI and CC using the Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A), a newly developed self- and informant report questionnaire in 29 patients with amnestic MCI, 28 CCs, and 30 demographically matched HCs. MCI and CC participants reported significant difficulties with selective aspects of executive functioning relative to HCs despite clinically normal performance on neuropsychological tests of this cognitive domain. Scores were generally in the pattern of MCI>CC>HC, and findings were most pronounced for working memory. Additionally, MCI and CC participants were more likely than their informants to report clinically meaningful executive problems, though informants identified a similar pattern of difficulty overall. Results failed to reveal strong relations between the BRIEF-A and standardized neuropsychological tests of executive function. Overall findings indicate that the BRIEF-A is sensitive to subtle executive changes in MCI and CC and suggest the need for research to determine if executive complaints are predictive of clinical course.

Aged↗

PubMed2005

Relationship of surgical approach to neurodevelopmental outcomes in hypoplastic left heart syndrome.

OBJECTIVE: Two strategies for surgical management are used for infants with hypoplastic left heart syndrome (HLHS), primary heart transplantation and the Norwood procedure. We sought to determine how these 2 surgical approaches influence neurodevelopmental outcomes at school age. METHODS: A multicenter, cross-sectional study of neurodevelopmental outcomes among school-aged children (>8 years of age) with HLHS was undertaken between July 2003 and September 2004. Four centers enrolled 48 subjects, of whom 47 completed neuropsychologic testing. Twenty-six subjects (55%) had undergone the Norwood procedure and 21 (45%) had undergone transplantation, with an intention-to-treat analysis. The mean age at testing was 12.4 +/- 2.5 years. Evaluations included the Wechsler Abbreviated Scale of Intelligence, Clinical Evaluation of Language Fundamentals, Wechsler Individual Achievement Test, and Beery-Buktenica Developmental Test of Visual-Motor Integration. RESULTS: The mean neurocognitive test results were significantly below population normative values. The mean full-scale IQ for the entire cohort was 86 +/- 14. In a multivariate model, there was no association of surgical strategy with any measure of developmental outcome. A longer hospital stay, however, was associated significantly with lower verbal, performance, and full-scale IQ scores. Aortic valve atresia was associated with lower math achievement test scores. CONCLUSIONS: Neurodevelopmental deficits are prevalent among school-aged children with HLHS, regardless of surgical approach. Complications that result in prolonged hospitalization at the time of the initial operation are associated with neurodevelopmental status at school age.

Adolescent↗

PubMed2005

Assessment of executive function in preschool-aged children.

Assessment of the overarching self-regulatory mechanisms, or executive functions, in any age group is challenging, in part due to the complexity of this domain, in part due to their dynamic essence, and in part due to the inextricable links between these central processes and the associated domain-specific processes, such as language, motor function, and attention, over which they preside. While much progress has been made in clinical assessment approaches for measuring executive functions in adults and to some extent in adolescents and school-aged children, the toolkit for the preschool evaluator remains sparse. The past decade, however, has seen a substantial increase in attention to executive functions in very young children from a developmental neuropsychological perspective. With this has come a necessity for better, more specific, and more internally valid performance measures, many of which are now described in the experimental literature. Few such tasks, however, have adequately demonstrated psychometric properties for clinical application. We present two performance tasks designed to tap selective aspects of executive function in preschoolers that are emerging from the experimental laboratory and hold promise of appropriate reliability and validity for the clinical laboratory. Performance tests alone, however, are insufficient to develop a comprehensive picture of a child's executive functioning. Thus, we present a rating scale of preschoolers' executive function in the everyday context, and advocate a model of executive function assessment that incorporates both controlled performance tasks that target specific aspects of executive function and parent/teacher ratings that target more global aspects of self-regulation in the everyday context.

Aptitude Tests↗

PubMed2005

Psychosocial treatment of children in foster care: a review.

A substantial number of children in foster care exhibit psychiatric difficulties. Recent epidemiological and historical trends in foster care, clinical findings about the adjustment of children in foster care and adult outcomes are reviewed, followed by a description of current approaches to treatment and extant empirical support. Available interventions for these children can be categorized as either symptom-focused or systemic, with empirical support for specific methods ranging from scant to substantial. Even with treatment, behavioral and emotional problems often persist into adulthood resulting in poor functional outcomes. We suggest that self-regulation may be an important mediating factor in the appearance of emotional and behavioral disturbance in these children.

Adolescent↗

PubMed2004

Psychometric and behavioral measures of central auditory function: the relationship between dichotic listening and digit span tasks.

We hypothesized that the Digit Span (DS) subtest and component tasks (Wechsler, 1991) would show strong relationships with a dichotic listening test (Musiek, 1983). In two sets of archival clinical data (N = 74 and N = 51) we demonstrated that: (a) individuals with central auditory deficits had lower DS scores, F(1, 72) = 7.34, p = .008; eta2 = .09; and (b) left-ear dichotic deficits impacted forward span, F(2, 48) = 8.45, p = .001. Right-ear dichotic listening performance also accounted for significant variance in digit forward span (R2 = 0.17, p = .003). While limited in scope, the studies conclude that forward but not reverse span performance is strongly related to dichotic listening, and can serve as a marker for possible central auditory deficits.

Adolescent↗

PubMed2004

Ecological assessment of executive function in traumatic brain injury.

Executive dysfunction is a common outcome in children who have sustained traumatic brain injury (TBI). Appropriate assessment of these complex interrelated regulatory functions is critical to plan for the necessary interventions yet present a challenge to our traditional methodologies. Ecological validity has become an increasingly important focus in neuropsychological assessment with particular relevance for the executive functions, which coordinate one's cognitive and behavioral capacities with real-world demand situations. The Behavior Rating Inventory of Executive Function (BRIEF) was developed to capture the real-world behavioral manifestations of executive dysfunction. Its development and various forms of validity, including ecological validity, are described. Application of the BRIEF's methodology to the assessment of executive dysfunction in TBI is provided. We advocate a multilevel approach to understanding executive function outcome in TBI, including traditional test-based measures of executive function, real-world behavioral manifestation of executive dysfunction, and the environmental system factors that impact the child. In this model, ecologically valid assessment of executive dysfunction provides an important bridge toward understanding the impact of component-level (i.e., test-based) deficits on the child's everyday adaptive functioning, which can assist the definition of targets for intervention.

Adaptation, Psychological↗

PubMed2004

Executive function in preschool children: examination through everyday behavior.

Clinical assessment of executive function in preschool-age children is challenging given limited availability of standardized tasks and preschoolers' variable ability to participate in lengthy formal evaluation procedures. Given the benefits of ecological validity of measuring behavior by rating scales, the Behavior Rating Inventory of Executive Function (Gioia, Isquith, Guy, & Kenworthy, 2000) was modified for use with children ages 2 through 5 years to assess executive functions in an everyday context. The scale development process, based on samples of 460 parents and 302 teachers, yielded a single 63-item measure with 5 related, but nonoverlapping, scales, with good internal consistency and temporal stability. Exploratory factor analyses identified 3 consistent factors: Emergent Metacognition, Flexibility, and Inhibitory Self-Control across parent and teacher samples. In a second study with a mixed sample of preschool children with various developmental disorders, parents and teachers rated these preschool children as having greater executive difficulties in most domains than matched controls. Such rating-scale methodology may be a useful complementary tool by which to reliably assess executive functions in preschool children via everyday behaviors in the natural environment.

Child Behavior↗

PubMed2002

Profiles of everyday executive function in acquired and developmental disorders.

Executive function profiles were examined within and between several clinical disorders via the multi-domain Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000). Parent ratings of children with Inattentive and Combined types of Attention-Deficit/Hyperactivity Disorder (ADHD-I, ADHD-C), Autistic Spectrum Disorders (ASD), moderate and severe Traumatic Brain Injury (TBI), and Reading Disabilities (RD) were compared with controls. Profile analysis revealed significant (p<.01) and substantial (eta2>.10) differences in global elevations and in profile of scale elevations between diagnostic groups. ASD, ADHD-I and ADHD-C groups exhibited greater elevations across the BRIEF scales than did RD and Severe TBI groups, who were in turn more elevated than Moderate TBI and Control groups. The ADHD-C group was unique in its frequency and severity of inhibitory deficits, while the ASD group was distinguishable by its deficits in flexibility. Within diagnostic groups, relative risk for executive dysfunction was calculated with variability present in the frequency of clinically elevated scales. While the BRIEF captures executive profiles characteristic of specific disorders in the clinical setting, it is not diagnostic in its own right and is best used within the context of a broad based evaluation.

Attention Deficit Disorder with Hyperactivity↗

PubMed2002

Confirmatory factor analysis of the Behavior Rating Inventory of Executive Function (BRIEF) in a clinical sample.

Evidence for the validity of the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) based on internal structure was examined in a sample of children with mixed clinical diagnoses via maximum likelihood confirmatory factor analysis. Four alternative factor models of children's executive function, based on current theories that posit a unidimensional versus fractionated model (Rabbitt, 1997; Shallice & Burgess, 1991), using the revised 9-scale BRIEF configuration that separates two components of the Monitor scale, were examined for model fit. A 3-factor structure best modeled the data when compared directly with 1-, 2-, and 4-factor models. The 3-factor model was defined by a Behavior Regulation factor consisting of the BRIEF Inhibit and Self-Monitor scales, an Emotional Regulation factor consisting of the Emotional Control and Shift scales, and a Metacognition factor composed of the Working Memory, Initiate, Plan/Organize, Organization of Materials, and Task-Monitor scales. The findings support a fractionated, multi-component view of executive function as measured by the BRIEF.

Adolescent↗