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Biomedical subjects

R M Ruff

Publications and source records attributed to R M Ruff.

10 recordsLinked to original sources
PubMed1992

Parallel and serial visual search after closed head injury: electrophysiological evidence for perceptual dysfunctions.

Event-related potentials (ERPs) were recorded from closed head injury (CHI) patients at least 2 years postinjury and from controls in order to assess their parallel and serial processing abilities during visual search. In Experiment 1, stimuli consisted of arrays of eight triangles; half of the arrays contained a target item. In the "feature-present" condition, the target item was a triangle with an additional horizontal line that could be detected automatically and in parallel, while in the "feature-absent" condition all items except for the target triangle had an additional horizontal line, thus requiring a serial search. In Experiment 2, stimuli consisted of eight solid bars (50%), seven solid bars and a vertical open bar (25%), and seven solid bars and a horizontal open bar (25%): the array containing the horizontal bar served as a target. By recording ERPs to the arrays containing vertical open bars, which were similar to the target items, parallel processing of "pop-out" stimuli could be studied in the absence of any overt response. ERP data were compared with the results of neuropsychological and neuroimaging (MRI, CAT) examination. Patient exhibited a decreased behavioral performance both in the parallel and in the serial processing mode. Furthermore, abnormalities of early and intermediate ERP components (P1, N1, P2, N2) were found, whereas the late component (P3) was less affected by CHI. The results were interpreted as an index of CHI-induced dysfunctions in perceptual processes such as simple feature registration and early target discrimination. It was suggested that these dysfunctions contribute to impairments of parallel as well as serial processes in visual search.

Adult↗
PubMed1992

The Ruff 2 and 7 Selective Attention Test: a neuropsychological application.

The neuropsychological application of the Ruff 2 and 7 Selective Attention Test as a measure of visual selective attention was investigated. The instrument was constructed as a paper-and-pencil approach to evaluate sustained attention utilizing different distractor conditions in the study of voluntary or intentional aspects of attention. Four patient groups with cerebral lesions confined to either the right or left anterior or left or right posterior region (ns = 8, 8, 8, 6) were studied. Patients with right-hemispheric lesions showed a greater over-all reduction in processing speed independent of the serial or parallel processing mode in comparison to individuals with left-sided lesions. Furthermore, as predicted, the two groups with anterior brain damage showed a larger discrepancy between serial and parallel processing modes than patients with posterior lesions. Specifically, the right frontal cases showed the greatest differential of accuracy on the serial and parallel tasks.

Adult↗
PubMed1991

Vegetative state after closed-head injury. A Traumatic Coma Data Bank Report.

To elucidate the clinical course of the vegetative state after severe closed-head injury, the Traumatic Coma Data Bank was analyzed for outcome at the time of discharge from the hospital and after follow-up intervals ranging up to 3 years after injury. Of 650 patients with closed-head injury available for analysis, 93 (14%) were discharged in a vegetative state. In comparison with conscious survivors, patients in a vegetative state sustained more severe closed-head injury as reflected by the Glasgow Coma Scale scores and pupillary findings and more frequently had diffuse injury complicated by swelling or shift in midline structures. Of 84 patients in a vegetative state who provided follow-up data, 41% became conscious by 6 months, 52% regained consciousness by 1 year, and 58% recovered consciousness within the 3-year follow-up interval. A logistic regression failed to identify predictors of recovery from the vegetative state.

Adolescent↗
PubMed1991

Neuropsychological sequelae of arteriovenous malformations.

A total of 24 patients harboring arteriovenous malformations (AVMs) in either the dominant hemisphere (n = 12) or the nondominant hemisphere (n = 12) were examined neuropsychologically. When compared with 24 matched normal control subjects, the AVM patients demonstrated differential degrees of impairment in verbal or visuospatial processing, depending on whether the lesion involved the dominant or nondominant hemisphere. As predicted, most compelling were the findings of cognitive deficit associated with the hemisphere contralateral to the AVM relative to matched normal control subjects. Evidence of higher cortical dysfunction contralateral to the residing AVM is discussed in the context of cerebrovascular steal.

Adult↗
PubMed1990

Computer-assisted attention retraining in head-injured individuals: a controlled efficacy study of an outpatient program.

The efficacy of a computer-assisted attention retraining program was evaluated with 29 outpatients suffering from moderate to severe traumatic brain injury. Ss who were at least 12 months postinjury were randomly assigned either to the attention training program or a memory training program that served as a control condition. Training lasted 9 weeks with two 2-hr sessions per week for both groups. The experimental design evaluated outcome by juxtaposing a multiple baseline procedure for a 1st set of measures of attention and memory with a pre and post group comparison that relied on a 2nd set of neuropsychological tests. The experimental group improved significantly in comparison with the control group on measures of attention. The reversed pattern for the memory measures was not observed. None of the treatment effects generalized to the 2nd set of dependent variables.

Adolescent↗
PubMed1990

Neurobehavioral outcome 1 year after severe head injury. Experience of the Traumatic Coma Data Bank.

The outcome 1 year after they had sustained a severe head injury was investigated in patients who were admitted to the neurosurgery service at one of four centers participating in the Traumatic Coma Data Bank (TCDB). Of 300 eligible survivors, the quality of recovery 1 year after injury was assessed by at least the Glasgow Outcome Scale (GOS) in 263 patients (87%), whereas complete neuropsychological assessment was performed in 127 (42%) of the eligible survivors. The capacity of the patients to undergo neuropsychological testing 1 year after injury was a criterion of recovery as reflected by a significant relationship to neurological indices of acute injury and the GOS score at the time of hospital discharge. The neurobehavioral data at 1 year after injury were generally comparable across the four samples of patients and characterized by impairment of memory and slowed information processing. In contrast, language and visuospatial ability recovered to within the normal range. The lowest postresuscitation Glasgow Coma Scale (GCS) score and pupillary reactivity were predictive of the 1-year GOS score and neuropsychological performance. The lowest GCS score was especially predictive of neuropsychological performance 1 year postinjury in patients who had at least one nonreactive pupil following resuscitation. Notwithstanding limitations related to the scope of the TCDB and attrition in follow-up material, the results indicate a characteristic pattern of neurobehavioral recovery from severe head injury and encourage the use of neurobehavioral outcome measurements in clinical trials to evaluate interventions for head-injured patients.

Adolescent↗
PubMedDate not supplied

Self-rating versus neuropsychological performance of moderate versus severe head-injured patients.

Head-injured patients frequently appear to be inaccurate in judging their cognitive functioning. To examine this clinical impression, self-ratings were compared with neuropsychological test performances. The sample was comprised of 28 patients with severe and 28 with mild-moderate head injuries, and these two groups were further subdivided according to chronicity, i.e. less than or equal to 1 year versus greater than 1 year between the date of injury and the evaluation. The control group of 31 adults was matched according to age and education. Head-injured patients rated themselves lower than normals regardless of severity of injury. Chronicity affected only the self-rating of learning and memory. The severely head-injured were generally less accurate when comparing self-ratings to test performance. However, this was not uniform across cognitive domains. Recommendations for self-assessment in neuropsychology are discussed.

Adolescent↗
PubMedDate not supplied

Cognitive rehabilitation versus day treatment in head-injured adults: is there an impact on emotional and psychosocial adjustment?

Emotional and psychosocial adjustments are typically the most challenging problems faced by the head injured, but there exists a paucity in research as to how affective problems are best ameliorated. In the present analysis, emotional and psychosocial adjustment were evaluated as part of a study comparing the efficacy of cognitive remediation versus day treatment. Out of 24 head-injured patients, half were randomly assigned into either treatment condition, each conducted 4 days a week over an 8-week span. A more favourable outcome for emotional adjustment was postulated for the day-treatment programme, since it was far more nurturing compared with cognitive remediation, which was thought to be more challenging if not confronting. However, our differential hypothesis for the two treatments was not confirmed, because in both groups there was a lessening of depression as measured by the Katz Adjustment Scale. The need is discussed for providing ongoing structured activities for the head injured in order to facilitate their emotional and psychosocial adjustment.

Adaptation, Psychological↗