Kimberly A. Kerns

Analysis of assets for virtual reality applications in neuropsychology

Abstract Virtual reality (VR) technology offers new opportunities for the development of innovative neuropsychological assessment and rehabilitation tools. VR-based testing and training scenarios that would be difficult, if not impossible, to deliver using conventional neuropsychological methods are now being developed that take advantage of the assets available with VR technology. If empirical studies continue to demonstrate effectiveness, virtual environment applications could provide new options for targeting cognitive and functional impairments due to traumatic brain injury, neurological disorders, and learning disabilities. This article focuses on specifying the assets that are available with VR for neuropsychological applications along with discussion of current VR-based research that serves to illustrate each asset. VR allows for the precise presentation and control of dynamic multi-sensory 3D stimulus environments, as well as providing advanced methods for recording behavioural responses. This serves as the basis for a diverse set of VR assets for neuropsychological approaches that are detailed in this article. We take the position that when combining these assets within the context of functionally relevant, ecologically valid virtual environments, fundamental advancements can emerge in how human cognition and functional behaviour is assessed and rehabilitated.

Investigation of a Direct Intervention for Improving Attention in Young Children With ADHD

The efficacy of a new set of child-oriented direct intervention materials, Pay Attention! (1994), was investigated in 14 children, ages 7 to 11 years, diagnosed with attention deficit hyperactivity disorder (ADHD). Treatment and control groups were matched for age, sex, and medication status. Both groups completed pre- and posttraining assessment batteries that included psychometric measures of attention, a measure of academic efficiency, and behavioral rating scales completed by parents and teachers. Results indicate that children who received the direct intervention did significantly better on a number of nontrained measures of attention and academic efficiency. Behavioral ratings of inattention-impulsivity and hyperactivity completed by parents did not differ following treatment, although a marginally significant improvement in inattention-impulsivity was noted by school teachers. These results suggest that direct interventions aimed at improving attention may be a valuable treatment option for improvi...

Magnetic resonance imaging outcomes from a comprehensive magnetic resonance study of children with fetal alcohol spectrum disorders

BACKGROUND Magnetic resonance (MR) technology offers noninvasive methods for in vivo assessment of neuroabnormalities. METHODS A comprehensive neuropsychological/psychiatric battery, coupled with MR imaging, (MRI), MR spectroscopy (MRS), and functional MRI (fMRI) assessments, were administered to children with fetal alcohol spectrum disorders (FASD) to determine if global and/or focal abnormalities could be identified, and distinguish diagnostic subclassifications across the spectrum. The 4 study groups included: (i) fetal alcohol syndrome (FAS)/partial FAS (PFAS); (ii) static encephalopathy/alcohol exposed (SE/AE); (iii) neurobehavioral disorder/alcohol exposed (ND/AE) as diagnosed with the FASD 4-Digit Code; and (iv) healthy peers with no prenatal alcohol exposure. Presented here are the MRI assessments that were used to compare the sizes of brain regions between the 4 groups. The neuropsychological/behavioral, MRS, and fMRI outcomes are reported separately. RESULTS Progressing across the 4 study groups from Controls to ND/AE to SE/AE to FAS/PFAS, the mean absolute size of the total brain, frontal lobe, caudate, putamen, hippocampus, cerebellar vermis, and corpus callosum length decreased incrementally and significantly. The FAS/PFAS group (the only group with the 4-Digit FAS facial phenotype) had disproportionately smaller frontal lobes relative to all other groups. The FAS/PFAS and SE/AE groups [the 2 groups with the most severe central nervous system (CNS) dysfunction] had disproportionately smaller caudate regions relative to the ND/AE and Control groups. The prevalence of subjects in the FAS/PFAS, SE/AE, and ND/AE groups that had 1 or more brain regions, 2 or more SDs below the mean size observed in the Control group was 78, 58, and 43%, respectively. Significant correlations were observed between size of brain regions and level of prenatal alcohol exposure, magnitude of FAS facial phenotype, and level of CNS dysfunction. CONCLUSIONS Magnetic resonance imaging provided further validation that ND/AE, SE/AE, and FAS/PFAS as defined by the FASD 4-Digit Code are 3 clinically distinct and increasingly more affected diagnostic subclassifications under the umbrella of FASD. Neurostructural abnormalities are present across the spectrum. MRI could importantly augment diagnosis of conditions under the umbrella of FASD, once population-based norms for structural development of the human brain are established.

The CyberCruiser: an investigation of development of prospective memory in children.

Prospective memory can be defined as the timely execution of a previously formed intention, and is critical in daily life because of its inherent involvement in goal-directed behavior. Cognitive systems involved in prospective memory have been hypothesized as involving the frontal cortex, and in adults, associated with working memory and executive functions. This study introduces a new computerized measure of prospective memory designed for children. In this study prospective memory is examined in a driving game task called the CyberCruiser. In a sample of 80 children ages 6-12 years, variables from this task demonstrated a significant age effect and were significantly correlated with other well known measures of executive function, even after controlling for chronological age. Performance on this task also demonstrated the anticipated pattern of strategic monitoring that has been demonstrated in other studies of prospective memory.

Time Reproduction, Working Memory, and Behavioral Inhibition in Children with ADHD

Barkley (1997a) proposed that the central deficit in Attention Deficit Hyperactivity Disorder (ADHD) is in behavioral inhibition, resulting in deficits both in working memory and sense of time. To test this theory, 21 children with ADHD and a matched sample (ages 6–13) completed a variety of tasks that measured behavioral inhibition, working memory, attention, and time reproduction. Children with ADHD performed significantly below controls on measures of inhibition, attention, and time reproduction. They did not differ significantly from controls, however, on tasks of working memory. In addition, performance on the working memory tasks was not correlated with the time reproduction task. We discuss the relevance of these results in the context of current theories of ADHD.

A Latent Variable Approach to Determining the Structure of Executive Function in Preschool Children

The composition of executive function (EF) in preschool children was examined using confirmatory factor analysis (CFA). A sample of 129 children between 3 and 5 years of age completed a battery of EF tasks. Using performance indicators of working memory and inhibition similar to previous CFA studies with preschoolers, we replicated a unitary EF factor structure. Next, additional performance indicators were included to distinctly measure working memory, set shifting, and inhibition factors. A two-factor model consisting of working memory and inhibition fit the data better than both a single-factor model and a three-factor model. Findings suggest that the structure of EF in preschoolers that emerges from CFA is influenced by task and performance indicator selection.

Time Reproduction in Children With ADHD: Motivation Matters

The primary goal of this study was to examine whether children with ADHD have a true deficit in subjective time sense, or whether their impairment reflects a motivational deficit. Thirty children with ADHD and 30 matched control children completed two versions of a time reproduction paradigm (“Regular” and “Enhanced”) in which motivational level was manipulated by the addition of positive sham feedback and the prospect of earning a reward. A secondary goal was to investigate performance on measures of working memory and behavioural inhibition, and how those constructs relate to time reproduction in the context of Barkley’s (1997a) model of ADHD. Children with ADHD performed significantly better on the motivating ‘Enhanced’ versus the Regular time reproduction paradigm, although they continued to perform significantly worse than controls on both tasks. Control children exhibited no reliable change in performance between versions of the task. Significant group differences were also observed on the working memory and behavioural inhibition tasks. We discuss the impact of motivation, working memory, and behavioural inhibition on time reproduction performance.

Utilization Behavior: Clinical Manifestations and Neurological Mechanisms

This paper describes a variety of motor release phenomena, including manual grasping and groping, imitation behavior, utilization behavior, and alien hand sign, their clinical manifestations, and proposed neural mechanisms. One of these specific neurobehavioral disorders, initially described by Lhermitte (Brain [1983] 106: 237–255), and termed utilization behavior, is addressed in more detail. Patients with this disorder are described as reaching out and using objects in the environment in an automatic manner. The current paper provides a comprehensive review of studies that have documented utilization behavior in individuals with a variety of pathologies, all having a specific predilection for the frontal lobes and frontal-striatal systems. Goldbergs (Behavioral and Brain Sciences [1985] 8: 567–616) theoretical framework for understanding motor release phenomena, which conceptualizes these behaviors as resulting from an imbalance between proposed medial (voluntary, goal directed, and future directed) and lateral (automatic, stimulus bound, and visually based) motor systems, is also discussed. Utilization behavior may prove to be a common underlying cause of high levels of excessive and intrusive motor behaviors within various clinical populations. A more comprehensive understanding of the neural systems underlying utilization behavior may prove highly useful for the differential diagnosis of conditions involving the mesial frontal cortex and fronto-striatal connections. Recent studies have started to investigate utilization behavior in clinical populations with known or suspected frontal system dysfunction, including adult patients with a variety of psychiatric conditions and children with ADHD.

Management of Attention and Memory Disorders Following Traumatic Brain Injury

Disorders of attention, memory, and executive function are common sequelae in children who have sustained traumatic brain injuries. Given the persistent nature of these deficits, there is a need for efficacious remedial approaches. Typically, remediation is approached through one of three general intervention strategies: externally focused interventions aimed at changing the environment so that the effect of the dysfunction is minimized, internally focused interventions aimed at improving the underlying cognitive ability, and compensatory interventions aimed at teaching children to use alternate strategies that lessen the impact of the dysfunction. This article describes current research involving these approaches for the treatment of attention and memory disorders in children.

Assessing multitasking in children with ADHD using a modified Six Elements Test.

The study was designed to investigate whether children with Attention Deficit Hyperactivity Disorder (ADHD) demonstrate a deficit in multitasking, measured by their performance on a modified Six Elements Test designed for use with children (C-SET). The C-SET was administered to 38 children, aged 7-13. The subjects comprised two groups: an ADHD sample (n = 19) and a community control sample (n = 19). The results show that the ADHD group performed significantly worse on the C-SET, in that they attempted fewer tasks than the control group. However, they did not commit more rule breaks. These findings suggest that children with ADHD did not have problems with retrospective memory, as they were as able to remember the rules as the control group. Rather, the ADHD children appeared to have a specific deficit in monitoring their ongoing behaviors and generating useful strategies for task completion, as indicated by the decreased number of tasks attempted compared to the control group. The number of tasks tried on the C-SET correlated significantly with a measure of working memory, but not with a measure of response inhibition. C-SET total tasks tried also correlated with all subscales of the Conners Parent Rating Scale-Revised (Short Version). The C-SET appears to be a useful measure of rule-governed multitasking behavior in children.