Frederiec K. Withaar

Fitness to drive in older drivers with cognitive impairment

This paper is a literature review on assessment of fitness to drive in older drivers with cognitive impairment. Early studies on dementia and driving generally failed to distinguish between safe and unsafe drivers on the basis of cognitive test performance. Predictive studies demonstrated that cognitively impaired persons as a group perform significantly worse than controls on both neuropsychological and driving measures. A high prevalence of cognitive impairment was found in groups of older drivers involved in traffic accidents and crashes. However, a large range in neuropsychological test scores has been found. Low to moderate correlations could be established between neuropsychological test results and on-road driving performance, making it difficult to discriminate between cognitively impaired subjects who are fit or unfit to drive. The review concludes with a discussion of methodological difficulties in the field of dementia and driving, including participant selection, the choice of neuropsychological tests, and the operationalization of driving performance.

The predictive value of measures of social cognition for community functioning in schizophrenia: implications for neuropsychological assessment.

The objective of this study was to examine the unique contribution of social cognition to the prediction of community functioning and to explore the relevance of social cognition for clinical practice. Forty-six schizophrenia patients and 53 healthy controls were assessed with tests of social cognition [emotion perception and Theory of Mind (ToM)], general cognition, and, within the patient sample, psychiatric symptoms. Community functioning was rated by nurses or family members. Social cognition was a better predictor of community functioning than general cognition or psychiatric symptoms. When the contributions of emotion perception and ToM were examined separately, only ToM contributed significantly to the prediction of community functioning. Independent living skills were poor in patients with impaired social cognition. In controls, social cognition was not related to community functioning. ToM was the best predictor of community functioning in schizophrenia. However, to fully understand a patients strengths and weaknesses, assessment of social cognition should always be combined with assessment of general cognition and psychiatric symptoms.

The efficacy of SMS text messages to compensate for the effects of cognitive impairments in schizophrenia

BACKGROUND AND AIMS Many people with schizophrenia have severe cognitive impairments that hamper their activities. The effect of pharmacological and behavioural interventions on cognitive functioning has been demonstrated, but even after successful intervention considerable impairments can remain. Therefore, we sought for alternative ways to help patients cope with the effects of their cognitive impairments. In the present study, we have evaluated the efficacy of short message service (SMS) text messages to compensate for the effects of cognitive impairments in schizophrenia in daily life. DESIGN A waiting list controlled trial was conducted: patients were quasi-randomly assigned to an A-B-A (baseline-intervention-follow-up) condition or an A-A-B-A condition that included an additional 7-week waiting list. The waiting list was included to control for the effect of time on relevant outcome. METHOD Sixty-two people with schizophrenia or related psychotic disorders were included in the study. All patients showed impaired goal-directed behaviour in daily life-situations. Patients were prompted with SMS text messages to improve their everyday functioning. The primary outcome measure was the percentage of goals achieved. RESULTS The overall percentage of goals achieved increased with prompting, while performance dropped to baseline level after withdrawing the prompts. Keeping appointments with mental health workers and carrying out leisure activities increased with prompting, while medication adherence and attendance at training sessions remained unchanged. A majority of the patients enjoyed receiving the SMS text messages. DISCUSSION Prompting can significantly improve achievement of a number of relevant goals. For other goals, combining prompting with interventions that enhance motivation seems indicated.

Fitness to Drive After Traumatic Brain Injury

This paper deals with the issue of fitness to drive in patients suffering from traumatic brain injury (TBI). Guidelines for assessment are proposed and three types of studies are reviewed: studies about impairments of attention and information processing, studies of driving competence, and driver selection studies, applying and evaluating the procedures for assessing fitness to drive. From these reviews a relicensing rate emerges of slightly over 50% for very severe TBI patients. Failures in relicensing particularly occur in patients with a very long duration of post-traumatic amnesia (exceeding 1 month), and with severe impairments of perception and judgement. Furthermore, a review of studies describing training of driving competence in traumatically brain-injured patients is presented. It is argued that graded procedures for (re)training should be developed and assessment should extend to training advice and prediction of training success. When expanding assessments according to this suggestion, evaluat...

Attention and driving in traumatic brain injury: a question of coping with time-pressure.

Background:Diffuse and focal traumatic brain injury (TBI) can result in perceptual, cognitive, and motor dysfunction possibly leading to activity limitations in driving. Characteristic dysfunctions for severe diffuse TBI are confronted with function requirements derived from the hierarchical task analysis of driving skill. Objective:Specifically, we focus on slow information processing, divided attention, and the development of procedural knowledge. Also the effects of a combination of diffuse and focal dysfunctions, specifically homonymous hemianopia and the dysexecutive syndrome, are discussed. Finally, we turn to problems and challenges with regard to assessment and rehabilitation methods in the areas of driving and fitness to drive.

What is measured by verbal fluency tests in schizophrenia

INTRODUCTION Schizophrenia patients perform below the norm on verbal fluency tests. The causes for this are unknown, but defective memory, executive functioning and psychomotor speed may play a role. METHOD We examined 50 patients with schizophrenia and related disorders, and 25 healthy controls with a cognitive test battery containing tests for verbal memory, executive functioning and psychomotor speed, and a categorical fluency test. RESULTS Patients obtained significantly lower test results than the controls on most cognitive measures including the verbal fluency test. During the fluency test, they formed as many clusters, and switched as often between clusters as the controls did, but they generated fewer words per cluster. Interestingly, in the control group, fluency performance was predicted by memory and executive functioning, but not by psychomotor speed. In patients, verbal fluency was predicted by psychomotor speed, but not by memory or executive functioning. DISCUSSION We conclude that psychomotor speed could be a crucial factor in cognition, and its influence on cognitive test performance should be considered in schizophrenia research. Furthermore, these data illustrate the importance of qualitative analysis of cognitive impairments in schizophrenia patients, as traditional cognitive tests often only provide quantitative information.

SMS text messages as a prosthetic aid in the cognitive rehabilitation of schizophrenia

Objective: To evaluate the efficacy of short message service (SMS) text messages as a compensatory aid to improve independence in individuals diagnosed with schizophrenia and cognitive deficits. Design: An ABA withdrawal single-case experimental design was used. Eight men diagnosed with schizophrenia took part in the study; all demonstrated memory or planning problems in everyday life. Results: Five participants completed the entire trial. Four were more successful in carrying out daily activities when receiving prompts, whereas I did not profit from the intervention. Conclusion: SMS text messages can be effective in compensating for cognitive impairment in some but not all individuals with schizophrenia.

Deviant Strategy on the Modified Six Elements Test in Patients with Schizophrenia

Impaired executive functioning is found in a considerable proportion of schizophrenia patients. Neuropsychological tests are originally designed to measure the behavior of neurological patients and may therefore miss psychiatry-related cognitive deficits. Qualitative information on tests for executive functioning is important in psychiatric populations. The Modified Six Elements Test (MSET) is a planning test that consists of 6 tasks, for which subjects have limited time and have to obey to switching rules. This study concerns a qualitatively different approach schizophrenia patients use on the MSET, and its relationship with cognitive measures. MSET scores and strategies of schizophrenia patients were compared to those of healthy controls, closed-head-injury patients, and peripheral injury patients. Also, schizophrenia patients and healthy controls were compared on verbal memory and vigilance. Schizophrenia patients finish fewer assignments on the MSET, receive a lower profile score compared to healthy controls, and use a different strategy on the test compared to the other groups. They also perform below healthy controls on the tests for verbal memory and vigilance. Use of the different strategy in schizophrenia patients was related to impaired cognitive functioning. An interesting strategy used by schizophrenia patients on the MSET appears to be indicative of impaired cognitive functioning. This strategy may be a compensatory strategy to spare cognitive resources. It could also be the result of a concrete interpretation of the test instructions.

Cognitive deficits and social functioning in schizophrenia: A clinical perspective

Impaired social functioning is one of the diagnostic features of schizophrenia. Cognitive functioning is also often impaired in several domains. Meta-analysis has shown a predictive value of cognition for a variety of domains related to social functioning (Green, Kern, Braff, & Mintz, 2000). The significance of these findings for clinical practice has remained largely uninvestigated, however, and is therefore taken up here. We investigated verbal memory, attention and executive functioning in 52 schizophrenia patients. Social functioning was assessed for different types of social roles. The percentages of cognitive and social impairments in our group were assessed according to clinical principles, normally used to judge an individual patient. A possible predictive relationship between cognition and social functioning was studied on the basis of these clinical criteria. A large proportion of patients showed impairments in both cognitive functioning and social functioning. However, the clinical method resulted in a successful prediction of social functioning in only 21–69% of the cases. Social functioning and cognitive functioning were impaired in a large proportion of patients, but were largely independent from each other. Since relationships between cognition and social functioning are weak, assessment procedures are inconsistent and possibly not optimally adjusted to the psychiatric population, the clinical relevance of cognitive testing in order to predict social functioning is as yet questionable.

Divided Attention After Closed Head Injury

Abstract: One of the most persisting sequelae of closed head injury (CHI) is a general slowing of information processing. With neuropsychological testing, the effect is already apparent in simple reaction time tests. The slowing is more pronounced in complex tasks requiring divided attention. This study aims at explaining impairments in divided attention in terms of reduced speed of information processing, and impaired mental flexibility. Three types of mental flexibility are proposed: Stimulus driven (four choice reaction time and auditory reaction time task), memory driven (Trailmaking B test), and strategy driven flexibility tasks (continuous tracking task and arrow identification task). Divided attention paradigms were studied in 26 subacute CHI patients and 25 orthopedic control subjects. Results demonstrated that a reduced speed of information processing was largely responsible for divided attention impairments. Additional impairments in complex divided attention tasks only emerged in the most compl...