Neurologic syndrome in 25 workers from an aluminum smelting plant.

BACKGROUND: This article expands on an earlier series of three patients with a neurologic syndrome, who had all worked in an aluminum smelting plant. METHODS: Twenty-five symptomatic workers from the same plant were referred for a standardized evaluation, including completion of a health questionnaire, neurologic examination, and neuropsychologic evaluation. An exposure index was calculated for each worker based on level and duration of exposure in the potroom, where exposures were the greatest. This index was correlated with symptoms, signs, and neuropsychologic test scores. RESULTS: Twenty-two (88%) of the patients reported frequent loss of balance, and 21 (84%) reported memory loss. Neurologic examination revealed signs of incoordination in 21 (84%) of the patients. Neuropsychologic test results showed preservation in certain spheres of functioning, such as verbal IQ, with substantial impairment in others, particularly memory functioning. On memory tests, 70% to 75% showed mild or greater impairment. The majority (17 of 19 tested, or 89%) showed depression on the Minnesota Multiphasic Personality Inventory. The exposure index was significantly correlated with signs and symptoms of incoordination. CONCLUSIONS: This study and others in humans and animals support the existence of a syndrome characterized by incoordination, poor memory, impairment in abstract reasoning, and depression. Aluminum exposure in the potroom seems the most likely cause.

Central nervous system manifestations in human immunodeficiency virus infection without AIDS.

To characterize neurological and neuropsychological findings associated with human immunodeficiency virus type-I (HIV) infection, 77 seropositive homosexual or bisexual males with no or minor symptoms of HIV were compared prospectively to 44 HIV seronegative men by observers blinded to serological status of the subjects. Neurological symptoms and examination findings were not significantly different between seropositives and seronegatives except for cranial nerve findings, predominantly mild hearing impairment. Mean performance scores for a 15-test neuropsychological battery were within an unimpaired range for both groups, although for five tests, mean scores were significantly poorer in seropositives. After adjustment for vocabulary score, and demographic and psychosocial variables, the mean score of seropositives was significantly worse only for the Benton Visual Retention Test. Magnetic resonance (MR) images of brain were abnormal in 14 (27%) of 52 seropositives and one of 10 seronegatives (value was not significant). HIV was isolated from cerebrospinal fluid (CSF) in 31 (61%) of 51 seropositives. The only clinical or laboratory difference between CSF culture positives and negatives was a higher CSF immunoglobulin synthesis rate in the former subjects (medians of 10.3 versus 0.1 mg/day; p = 0.03). An additional 13 seropositive subjects had immunologic evidence of central nervous system HIV infection, defined by a serum-to-CSF HIV antibody ratio of less than 5.5. Intracranial abnormalities on MR imaging were associated with CSF immunologic responses to HIV. Nervous system involvement occurred in the vast majority of men with early HIV infection, but clinically significant impairment was uncommon.

Neurobehavioral outcomes in cardiac operations. A prospective controlled study.

To assess the severity and duration of new organic brain dysfunction after cardiac operations, we used an extensive battery of neuropsychologic tests to evaluate 65 patients undergoing coronary artery bypass grafting and 25 patients undergoing intracardiac operations with cardiopulmonary bypass. Patients were tested the day before the operation, before discharge from the hospital, and approximately 7 months later. Compared to 47 nonsurgical control subjects tested at comparable time intervals, surgical subjects showed generalized impairment of neuropsychologic abilities near the time of discharge from the hospital. At follow-up testing, there was no evidence of residual impairment among the surgically treated patients as a whole. In fact, they showed greater improvement compared to initial test scores than did control subjects. However, performance of 10 patients (11%) declined on half of the neuropsychologic variables between preoperative and follow-up testing. Neurobehavioral outcome was not related to the type of operation (coronary bypass versus intracardiac), to factors of cardiopulmonary bypass (duration, aortic occlusion time, hypotension, arterial carbon dioxide tension, minimum hematocrit value, minimum temperature). The only predictor of negative outcome was advanced age. We conclude that, although neurobehavioral impairment is common during hospitalization after cardiac operations, the prognosis for eventual full recovery is favorable, although less so among the elderly.

Cognition and metacognition at extreme altitudes on Mount Everest.

The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.

Diagnosis of attention deficit disorder with hyperactivity in Chinese boys.

Parental and teacher ratings of adjustment on the Achenbach Child Behavior Checklist and Teacher Rating Form were obtained on 39 subjects diagnosed as having attention deficit disorder with hyperactivity (ADDH), 31 subjects with ADDH plus learning disability (ADDH-LD), and 29 controls. Subjects were all males between the ages of 9 and 11 years and resided in Changsha, People's Republic of China. Significant group differences were found between the two clinical groups and the control group. Ratings by parents and teachers of the ADDH and ADDH-LD groups indicated more behavior problems and poorer social adjustment than controls. ADDH and ADDH-LD groups were not significantly different from one another except on ratings of school and learning problems.

Prospective cerebral MR study of HIV seropositive and seronegative men: correlation of MR findings with neurologic, neuropsychologic, and cerebrospinal fluid analysis.

PURPOSE: As part of a longitudinal study of human immunodeficiency virus type 1 (HIV) infection, we attempted to identify early cerebral MR findings that might correlate to clinical evidence of central nervous system involvement. METHODS: We studied 65 seropositive and 40 seronegative homosexual males using cranial MR, neurologic, immunologic, and neuropsychologic examinations. RESULTS: The incidence of mildly enlarged ventricles, sulci, and punctate areas of abnormal signal in both groups was similar in both groups. Diffuse, poorly defined areas of abnormal white matter signal were difficult to consistently identify in seropositives. Enlarged adenoidal lymphoid tissue was found in 30 (46%) of seropositives and 2 (5%) of seronegatives (P = .0001). The incidence of sinus inflammatory change was similar in the two groups. CONCLUSION: MR of intracranial contents is substantially normal in a non-AIDS HIV(+) population.

Equivalence of the Color Trails Test and Trail Making Test in nonnative English-speakers.

The Color Trails Test (CTT) has been described as a culture-fair test of visual attention, graphomotor sequencing, and effortful executive processing abilities relative to the Trail Making Test (TMT). In this study, the equivalence of the TMT and the CTT among a group of 64 bilingual Turkish university students was examined. No difference in performance on the CTT-1 and TMT Part A was found, suggesting functionally equivalent performance across both tasks. In contrast, the statistically significant differences in performance on CTT-2 and TMT Part B, as well as the interference indices for both tests, were interpreted as providing evidence for task nonequivalence of the CTT-2 and TMT Part B. Results have implications for both psychometric test development and clinical cultural neuropsychology.

Factor analysis of the Wechsler Memory Scale: is the associate learning subtest an unclear measure?

A factor analysis of the Wechsler Memory Scale (WMS) with 30-minute delayed recall scores (percent retained) for the Logical Memory, Visual Reproduction, and Associate Learning subtests indicated that this variant of the WMS taps different types of learning and memory for new material. With regard to the verbal learning/recall subtests, Logical Memory appears to be related to attention/ concentration ability, while Associate Learning is relatively independent. The results also showed that both the easy and hard items from Associate Learning tap the same ability, providing evidence that this subtest is a measure of rote verbal learning. These results support the clinical utility of the WMS with delayed recalls in neuropsychiatric populations.

Age group differences on neuropsychological battery performance in a neuropsychiatric population: an international descriptive study with replications.

The relationship of age to performance on the Halstead-Reitan Neuropsychological Battery was examined in three samples drawn from neuropsychiatric populations: an initial sample of 217 subjects, a within-laboratory replication of 307 subjects, and a cross-national replication sample of 101 subjects. The results showed significant relationships of age to subtests of the Halstead-Reitan Battery involving problem-solving abilities and motor strength, which were replicated across the three samples. Verbal and perceptual subtests were not consistently related to age across samples. For those problem-solving and motor tests showing replicated correlations with age. mean scores are provided for three age groups (16-34, 35-54, and 55 and above), and group differences were tested with analysis of variance. These results help clarify for which measures age group differences are consistent in neuropsychiatric populations. Implications of these results for treatment program planning are discussed

Hemodilution of polycythemic mountaineers: effects on exercise and mental function.

We studied the effects of acute, isovolemic hemodilution on the exercise ability and mental function of four polycythemic mountain climbers (mean hematocrit 58 +/- 1.25%) during the American Medical Research Expedition to Mt. Everest (AMREE). The subjects were studied at 5400 m (PB = 400 mm Hg). Approximately 15% of their blood volume was removed and replaced with an equal volume of 5% human albumin solution. Final hematocrits were 50.5 +/- 1.5%. Before and after hemodilution, the subjects performed psychological and exercise tests. Maximum work level, oxygen uptake, minute ventilation, and blood oxygen saturation did not change. After hemodilution, heart rate increased slightly at all work levels, and there was a small but significant improvement on the psychological tests. It is concluded that this degree of hemodilution was well tolerated and that a hematocrit of greater than 50% conferred no advantage for exercise and may have impaired cerebral function. Although, in these circumstances, isovolemic hemodilution improved cerebration, we feel that this potentially hazardous maneuver is rarely indicated.

Neurobehavioral and psychosocial functioning of women exposed to high altitude in mountaineering.

The effects of chronic hypoxemia upon cognition and behavior were studied in women exposed to high altitude in mountaineering. Neuropsychological tests and psychosocial and physiological questionnaires were given to eight women before, during, and immediately after a Himalayan climb to 20,500 feet. Cognitive functioning remained relatively intact with only two significant decrements, complex abstract reasoning and word-finding ability. Significant changes were found on all psychosocial and physiological questionnaires. Feelings of acceptance of others and anxiety declined significantly. Physical symptoms were greatest during the first five days of ascent. Subjects' self-ratings of mental functioning were significantly better after the expedition than either before or during the climb. Self-assessments were correlated with emotions and physical symptoms, not with actual performances on the test battery. It is suggested that complex cognitive tasks and psychosocial functioning be studied in more detail as these were more influenced by exposure to high altitude in mountaineering.

Fingertip number-writing errors by psychiatric patients.

Records from 495 psychiatric patients from two neuropsychology laboratories indicated the Fingertip Number Writing test shows a significant and reliable left-hand advantage within and between laboratories. While the left-hand advantage may reflect a right-hemisphere superiority for tactile-spatial processing, it is not possible to distinguish between right hemispheric functional superiority and practice effects between hands because the standard fingertip writing task always starts with the right hand.

Differences in psychological sex, adjustment, and familial influences among homosexual and nonhomosexual populations.

The present study investigated differences in psychological sex, present and past adjustment, and parental influences among homosexual cross-dressers, homosexual non-cross-dressers, applicants for sex change surgery, and heterosexuals. The homosexual non-cross dresser and heterosexual groups were found to have the most masculine gender role, with the sex change group having the most feminine gender identity. The two homosexual groups were most accepting of homosexuality, with the sex change group having the least acceptance of homosexuality. Support was not found for the prediction that the sex change group would have the worst present and past adjustment followed by the homosexual cross-dressers with the poorest past adjustment. As predicted, however, fathers were perceived as more nurturant in the heterosexual group than among the remaining three groups. These findings suggest that variations in sexual-life-style can be understood as manifestations of different combinations of the components of psychological sex and that a nurturant father is important in the development of a heterosexual life-style.