Reconstructive memory bias in recall of neuropsychological symptomatology.

Subjective recall of symptoms among nonlitigants with closed-head and back injuries and non-injured participants with high and low levels of life stressors was evaluated. All participants completed a demographic questionnaire, the Brief Symptom Inventory, and a symptom checklist. Recall of symptoms by participants with closed-head and back injuries was consistent with perceptions of being worse now than they were before their injuries. The results further suggest that these participants tend to overestimate the actual degree of change that has taken place by recalling fewer pre-injury symptoms than control participants. In addition, participants with closed-head injuries, but not with back injuries, showed significantly higher levels of symptom endorsement now than controls.

Neuropsychological toxicology of methylene diphenyl diisocyanate: a report of five cases.

The neuropsychological functioning of five men suffering alleged physical, cognitive and behavioural changes following exposure to methylene diphenyl diisocyanate (MDI), an industrial chemical, was investigated in the present study. At the time of assessment, four of the five patients remained symptomatic despite having no contact with MDI for periods ranging from 5 to 9 months. All patients reported experiencing subjective symptoms consisting of respiratory distress, headaches, depression, irritability, forgetfulness, decreased calculating ability, word-finding problems and reduced concentration. While the pattern of neuropsychological deficits varied among the patients, common findings for the group included intact psychomotor, psychosensory, visuographic and language functions accompanied by deceased concentration, mental efficiency, rate of information processing, learning ability and abstract reasoning. All five patients also revealed significant emotional distress on an objective personality measure. In general, the neuropsychological test data support the presence of behavioural and cognitive correlates of CNS injury following exposure to MDI.

Neuropsychological sequelae of methyl bromide: a case study.

Methyl bromide (MB) is a pesticide used primarily as a fumigating agent for homes, storage vehicles and soil. Chronic exposure to MB is known to cause damage to the central nervous system and other organs. Previously published post-mortem studies have also revealed significant brain abnormalities in patients whose deaths were attributed to MB. Only one study to date has examined the neuropsychological effects of this potential neurotoxin. The present case report documents the events surrounding an incident of acute and subacute MB exposure following home fumigation and the neuropsychological after-effects associated with that exposure. Behavioural and cognitive correlates of CNS dysfunction revealed by the neuropsychological testing included impairments in concentration, information processing, learning and memory. Emotional sequelae appeared to be a secondary problem associated with fears over physical well-being and impaired cognition. The cognitive symptomatology did not abate after completion of litigation and award of compensation.

Effects of sophistication and motivation on the detection of malingered memory performance using a computerized forced-choice task.

The present study employed a computerized forced-choice recognition memory task, the Multi-Digit Memory Test (MDMT), to examine the effects of instructional set (i.e., dissimulation information provided subjects) and motivation (i.e., monetary incentive) on simulated malingering behavior in a group of 119 university undergraduate students and 33 patients sustaining varying severity of closed-head injury. For the nonpatient groups, a significant effect of instructional set was revealed. Motivational incentive, however, did not affect forced-choice performance. Overall, significant performance differences emerged between all groups with nonmalingering students performing nearly perfectly, the brain-injured patients performing well above chance levels, sophisticated student malingers performing at chance, and naive student malingers performing well below chance levels. These results suggest the MDMT may offer a clinically useful and convenient addition to a neuropsychological assessment when there is suspicion of feigned memory problems. These data also support the use of naive and sophisticated malingering subjects in further analog studies addressing this topic.

Remediation of alexia without agraphia: a case study.

Following a left temporoparietal-occipital haemorrhage and surgery, a 43-year-old, right-handed male exhibited alexia without agraphia. A remediation programme consisted of training in head turning to compensate for a right visual field defect, letter-by-letter reading aloud and covertly, drill with flash-cards to improve word recognition and practice in naming objects to improve dysnomia. The patient's reading improved markedly over a 6-week period and he was able to resume work as a respiratory therapy supervisor. A post-morbid depression resolved concomitantly with the patient's return to work. The training programme and the patient's post-training approach to reading are discussed in terms of hemispheric functioning as well as 'direct path' and 'indirect path' reading. The effectiveness of training is considered in the context of spontaneous recovery.

Lateralized cerebral dysfunction in early and late stage alcoholics.

The neuroanatomical consequences of chronic alcohol ingestion were investigated using verbal and nonverbal neuropsychological measures known to be sensitive to the integrity of the left and right cerebral hemispheres, respectively. The performances of a group of 15 men alcoholics with a self-reported drinking history of less than 10 years and a group of 15 men alcoholics with a self-reported drinking history of 10 or more years were compared to that of a group of 15 men nonalcoholic controls. A multiple covariate analysis was done prior to analyzing group differences to determine what influence three covariates (age, education and socioeconomic status) had on the group performances. Some of the tests were significantly influenced by age or education and group differences were analyzed with adjustment for the appropriate covariate. Late stage alcoholics were significantly impaired in some tests of both right and left hemisphere functioning relative to controls. The performance of early stage alcoholics fell between that of controls and late stage alcoholics on most measures and differed significantly from either group on only one measure, where early stage alcoholics were superior to late stage alcoholics. Greater duration of alcoholism and higher average daily consumption were significantly related to decreased performance on some neuropsychological tests used.

The relationship between neuropsychological functioning and psychopathology in temporal lobe epileptic patients.

With the use of Goldberg's method of Minnesota Multiphasic Personality Inventory (MMPI) analysis, evidence has been recently provided of a positive relationship between psychopathology and deficits in neuropsychological functioning in epileptic patients. The present study attempted to replicate this finding using more precise and appropriate criteria for grouping patients according to severity of neuropsychological impairment. Application of Goldberg's MMPI Rules to 34 temporal lobe epileptic patients grouped according to their neuropsychological status (nonimpaired or impaired) failed to support these findings. Possible reasons for the discrepant results, including differing methodologies and seizure patient characteristics across studies, are discussed.