Ned L. Kirsch

Assistive technology for cognitive rehabilitation: State of the art

For close to 20 years, clinicians and researchers have been developing and assessing technological interventions for individuals with either acquired impairments or developmental disorders. This paper offers a comprehensive review of literature in that field, which we refer to collectively as assistive technology for cognition (ATC). ATC interventions address a range of functional activities requiring cognitive skills as diverse as complex attention, executive reasoning, prospective memory, self-monitoring for either the enhancement or inhibition of specific behaviours and sequential processing. ATC interventions have also been developed to address the needs of individuals with information processing impairments that may affect visual, auditory and language ability, or the understanding of social cues. The literature reviewed indicates that ATC interventions can increase the efficiency of traditional rehabilitation practices by enhancing a persons ability to engage in therapeutic tasks independently and by broadening the range of contexts in which those tasks can be exercised. More importantly, for many types of impairments, ATC interventions represent entirely new methods of treatment that can reinforce a persons residual intrinsic abilities, provide alternative means by which activities can be completed or provide extrinsic supports so that functional activities can be performed that might otherwise not be possible. Although the major focus of research in this field will continue to be the development of new ATC interventions, over the coming years it will also be critical for researchers, clinicians, and developers to examine the multi-system factors that affect usability over time, generalisability across home and community settings, and the impact of sustained, patterned technological interventions on recovery of function.

Altitudinal neglect following traumatic brain injury: a case report.

We present an analysis of altitudinal neglect in a patient who following traumatic brain injury showed extinction to a visual stimulus presented in the lower field when another stimulus was simultaneously presented in the upper field. When estimating the midpoint of vertically-oriented rods presented below eye level using visual cues, tactile/kinesthetic cues or a combination of these cues, she consistently pointed higher than control subjects did. She showed less severe impairments when the rods were presented at or above eye level. When estimating the midpoint between two clicks presented above and below her head, she pointed higher than did control subjects. These deficits cannot be accounted for by sensory or motor disorders and appear to be due to a disorder in attending to stimuli in the lower half to space.

Health status, not head injury, predicts concussion symptoms after minor injury.

OBJECTIVE Postconcussion (PC) syndrome etiology remains poorly understood. We sought to examine predictors of persistent PC symptoms after minor injury. METHODS Health status, symptom, and injury information were obtained on a sample of patients presenting to the emergency department after minor injury. Postconcussion and cognitive symptoms were assessed at 1, 3, and 12 months. RESULTS Among 507 patients enrolled, 339 had head injury. Repeated-measures logistic regression modeling of PC and cognitive symptom presence across time indicated that baseline mental health status and physical health status were most predictive of persistent symptoms. In contrast, head injury presence did not predict persistent PC syndrome. DISCUSSION Baseline mental health status and physical health status were associated with persistent PC syndrome after minor injury, but head injury status was not. Further studies of PC syndrome pathogenesis are needed.

The effect of lateralized dynamic stimuli on unilateral spatial neglect following right hemisphere lesions

Patients with unilateral (left-sided) spatial neglect following right-hemisphere stroke were tested for the effects of visual stimulation on performance of a line-bisection task. As predicted from research on brain mechanisms of spatial orientation and attention, dynamic visual stimuli presented on the left side substantially reduced neglect in the task. In contrast, left sided static stimuli reduced neglect significantly less and dynamic stimuli presented in the center had no effect on neglect. Neglect patients with hemianopia did not show significantly less benefit of left-sided dynamic stimuli compared to neglect patients without hemianopia, suggesting that the effect of these stimuli was unconscious and automatic. The potential advantages of lateralized dynamic stimuli in the rehabilitation of neglect are discussed.

Computer-assisted interactive task guidance: Facilitating the performance of a simulated vocational task

Compensatory systems can be helpful for Individuals with traumatic brain injuries whose functional skills do not Improve in response to other types of treatment. An interactive computer–assisted compensatory cuing system, designed to assist brain–injured patients with the performance of functional skills, is described. By using this system, two of four patients Improved their performance of a simulated janitorial task. The advantages and disadvantages of interactive cuing systems are discussed, including their use as a pragmatic intervention for patients who benefit from successful experiences while they are learning at a much slower pace.

Prevalence and Associated Features of Depression and Psychological Distress in Polio Survivors

This cross-sectional study examines the prevalence of psychological distress and depression among 116 polio survivors. It investigates demographic, medical, and coping differences between subjects with (n = 17) and without (n = 99) these symptoms. Subjects were administered the Brief Symptom Inventory (BSI), the Coping with Disability Inventory (CDI), and a questionnaire about their polio histories. The BSI provided measures of psychological distress and depression that defined the subgroups. The CDI assessed coping behaviors. BSI scores for the overall sample were within the normal range indicating no major distress, depression, nor elevated somatic complaints. Several significant differences were found between the two subgroups. On average, depressed/distressed subjects reported an increase in pain (p < .01) and further deterioration of their medical status since the time of their physical best subsequent to the onset of polio (p < .01). They consistently rated their health as poorer than did nondepressed/nondistressed subjects (p < .001). They also reported less satisfaction with life and their occupational status (p < .001) and displayed poorer coping behaviors combined (p < .001). Selected variables such as life satisfaction, pain, decrease in activity, and current living situation accounted for 51% of the variance when predicting distress and depression among this group of polio survivors.

Evaluating a Clinical Measure of Reaction Time: An Observational Study

The present study was an initial evaluation into the reliability and validity of a novel clinical measure of reaction time that consists of a vertical cylinder that is released and caught as quickly as possible. 65 healthy adults performed clinical and computerized reaction time tasks (RTclin and RTcomp) under simple and dual-task conditions. RTclin demonstrated excellent test-retest and interrater reliabilities and was significantly correlated with the criterion standard RTcomp. RTclin increased with increasing age and when tested under dual-task conditions. These preliminary results suggest that RTclin is a reliable and valid measure of reaction time.

Aggregating Validity Indicators Embedded in Conners' CPT-II Outperforms Individual Cutoffs at Separating Valid from Invalid Performance in Adults with Traumatic Brain Injury

Continuous performance tests (CPT) provide a useful paradigm to assess vigilance and sustained attention. However, few established methods exist to assess the validity of a given response set. The present study examined embedded validity indicators (EVIs) previously found effective at dissociating valid from invalid performance in relation to well-established performance validity tests in 104 adults with TBI referred for neuropsychological testing. Findings suggest that aggregating EVIs increases their signal detection performance. While individual EVIs performed well at their optimal cutoffs, two specific combinations of these five indicators generally produced the best classification accuracy. A CVI-5A ≥3 had a specificity of .92-.95 and a sensitivity of .45-.54. At ≥4 the CVI-5B had a specificity of .94-.97 and sensitivity of .40-.50. The CVI-5s provide a single numerical summary of the cumulative evidence of invalid performance within the CPT-II. Results support the use of a flexible, multivariate approach to performance validity assessment.

Nature and implications of selective impairment on the booklet category test and Wisconsin card sorting test

Abstract The neuropsychological characteristics of patients, selected on the basis of their pattern of performance on the Booklet Category Test (BCT) and the Wisconsin Card Sorting Test (WCST), were assessed. Correlation and factor analyses revealed that the BCT and WCST shared minimal variance in a neuropsychological test battery. There were no statistically significant differences on individual neuropsychological tests between groups of patients with selective impairment on the BCT or WCST. It was concluded that the BCT and WCST are not interchangeable, and that they assess different aspects of cognitive functioning. The nature of the difficulties of patients with selective impairment on the BCT or WCST were discussed.

Automatic assessment of cognitive impairment through electronic observation of object usage

Indications of cognitive impairments such as dementia and traumatic brain injury (TBI) are often subtle and may be frequently missed by primary care physicians. We describe an experiment where we unobtrusively collected sensor data as individuals with TBI performed a routine daily task (making coffee). We computed a series of four features of the sensor data that were increasingly representative of the task, and that we hypothesized might correlate with severity of cognitive impairment. Our main result is a significant correlation between the most representational feature and an apparent indicator of general neuropsychological integrity, namely, the first principal component of a standard suite of neuropsychological assessments. We also found suggestive but preliminary evidence of correlations between the computed features and a number of the individual tests in the assessment suite; this evidence can be used as the basis of larger-scale studies to validate significance.