Polarizing calcifications.
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Biopsy, Needle↗
Biomedical subjects
H W Gordon
Publications and source records attributed to H W Gordon.
Introduction: individual differences in the biobehavioral etiology of drug abuse.
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Disease Susceptibility↗
Ultradian rhythms in performance on tests of specialized cognitive function.
Performance on cognitive tasks cycled at ultradian frequencies for 24 males over a test period of eight hours. The verbal task of written word production cycled at 80 minutes; the spatial task of locating points in space cycled at 96 minutes. Multiple cycles were seen for a perceptual speed task that factor loads on both the verbal and spatial task. Replication of the results for the first 12 and second 12 subjects demonstrated their robustness. The verbal and spatial tasks were chosen to reflect specialized functions of the left and right cerebral hemispheres, respectively. Accordingly, the results are interpreted as evidence that specialized task performances are associated with independent neurochemical systems. In addition, blood samples were taken at task performance to assess cyclicity of hormone levels. Luteinizing hormone had a period of 120 minutes, testosterone and cortisol were inconsistent and none seemed to be related to the cognitive tasks. However when subjects were divided according to a winter or summer testing schedule, the spatial periodicity was absent for the summer group and the verbal periodicity was absent for the winter peak.
Activity Cycles↗
Human neuroscience at National Institute on Drug Abuse: implications for genetics research.
It is becoming clear that there is a genetic component to drug abuse. Family studies, adoption studies, and critical twin studies have all pointed to some genetic vulnerability or risk factors for an individual to abuse psychoactive drugs depending on certain psychopathologies in the biological parents and/or parents' own drug use. The question for the next generation of research at the National Institute on Drug Abuse (NIDA) is to apply the rapidly developing technology in molecular genetics in an effort to determine the candidate genes contributing to the risk.
Adoption↗
A neuropsychologic profile of adolescent alcoholics.
Male and female adolescents who qualified for a DSM-III-R diagnosis of Alcohol Abuse or Dependence and a control sample of nonalcohol-abusing male and female adolescents were administered a battery of intellectual, achievement, and neuropsychologic tests. Alcohol-abusing adolescents were found to have significantly lower verbal and full-scale IQ scores than controls. Furthermore, alcohol-abusing adolescents were found to have a trend toward lower age-standardized scores on achievement tests of reading ability and spelling. Surprisingly, alcohol-abusing adolescents made less perseverative errors and commission errors on a learning and memory task than controls. Control males performed worse on the Wisconsin Card Sort than alcoholic males, whereas alcohol-abusing females performed worse than control females. In addition, alcoholic subjects scored better than controls on a measure of visual memory sensitivity. The results indicate that adolescent alcohol abusers in general have poorer language skills than adolescents who do not abuse alcohol. However, in contrast to results obtained from studies of adult alcoholics, there is little evidence of significant brain damage as revealed by using neuropsychologic test performance.
Adolescent↗
No difference in cognitive performance between phases of the menstrual cycle.
No differences were seen in performance on either verbosequential or visuospatial neuropsychological tests among three groups of women. There were also no differences among the phases of the menstrual cycle on any of the tests. The design of this study was to sample performance of women on verbosequential and visuospatial neuropsychological tests during phases of the normal menstrual cycle in regularly menstruating women, and at comparable time points among women taking oral contraceptives and among those who had amenorrhea. Serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol, and progesterone were assayed to document these hormone levels at each time point for each group. These data are consistent with previous results in our laboratory but conflict with other reports in which shifts in cognitive function were related to fluctuations in estrogen. The only indications of positive results were weak correlations with gonadotropins and cognitive function across subjects. While some of these correlations replicated previous results, they were weak and should be considered with caution.
Adult↗
Laterality for music perception in musicians, mathematicians, and dancers: jumping to conclusions.
Group differences for ear asymmetries for a melodies task were reported for talented music, mathematics, and dance students. Evidence is presented that it is premature to conclude that these group differences were the result of specialized training in their areas of expertise.
Aptitude↗
The influence of gender, handedness, and performance level on specialized cognitive functioning.
Individual differences in performance on neuropsychological tests were analyzed across age (prepubertal to adult), gender, and handedness groups and examined for performance level as a moderating variable. No differences were observed for the factor structure of these tests across ages and between genders, suggesting similar cognitive structures among these groups. Significant differences in performance were observed between males and females and, to a lesser extent, between right and left handers. Of interest, were significant Gender x Handedness and Gender x Handedness x Level (of performance) interactions seen especially in the older (postpubertal and adult) subjects. High performing, right handed males and left handed females performed better on visuospatial tasks while left handed males and right handed females performed better on verbosequential tasks.
Adolescent↗
Hemisphericity and its validity for education, vocation, and cognitive style.
Six studies are described demonstrating practical use for individual assessment of specialized cognitive function associated with the left and right cerebral hemispheres. Study #1 demonstrates that the majority of referred reading difficulties have a cognitive profile for which verbosequential abilities are 0.5 SD below average, while visuospatial abilities are 0.5 SD above average. Study #2 also demonstrates that first degree family members of dyslexics favor visuospatial skills. Study #3 demonstrates that public school children have lower reading but not lower arithmetic scores if their cognitive profile favors visuospatial skills. Study #4 demonstrates that visuospatial skills were predictive of success in training military pilots. Study #5 demonstrates a modest association of cognitive function and management skill. Finally, study #6 demonstrates that valid tests of brain function were not related to preference inventories purportedly designed to measure the same thing. The conclusion from these studies is that tests assessing specialized cognitive function may be useful in some areas of prediction of academic success and, to a lesser degree, management success. But caution in interpretation is advised because not all predictions were supported by the data.
Cognition↗
Ultradian rhythms of right and left hemisphere function.
Two studies are described that demonstrate ultradian shifts in performance on tests of specialized function associated with the left or right cerebral hemispheres. The first study demonstrated that right-handed males who were tested upon wakening from Rapid Eye Movement sleep performed relatively better on visuospatial skills compared to themselves when tested upon wakening from Non-Rapid Eye Movement sleep. In the second study, subjects were tested continuously for eight hours on a written word production test, a test of point localization, and a test of symbol digit substitution. Each of the tests was performed cyclically but with different periods. The results from both studies suggest that underlying cerebral mechanisms for verbosequential and visuospatial function are neurochemical in nature and not neuroanatomical because of the rapid (ultradian) shifts in performance level.
Biological Clocks↗
Specialized cognitive function and reading achievement in hearing-impaired adolescents.
This study evaluated the performance of hearing-impaired adolescents on tests of specialized cognitive functioning and explored the linkage between cognitive profile and reading achievement. Other variables noted were mathematics achievement, speech production, etiology, and age of onset of hearing loss. Subjects were 62 severely-to-profoundly hearing-impaired students between 15 and 20 years of age, 31 "high readers" and 31 "low readers." Results indicated that, for this sample, cognitive function was below average for the verbal and sequential skills associated with the left hemisphere but above average for the "visuospatial" skills associated with the right hemisphere. Reading performance proved to be highly correlated with cognitive profile, as did mathematics performance and, to a lesser extent, speech and age of onset. Ramifications for instruction are discussed--in particular, development of strategies for using the right hemispheric cognitive strengths, as identified in this sample, to help overcome the deficits in "verbosequential" processing and reading achievement traditionally associated with hearing-impaired students.
Achievement↗
A relationship between gonadotropins and visuospatial function.
Follicle Stimulating Hormone (FSH) levels were negatively correlated with visuospatial function in two successive testing sessions in 32 young adult men. Men with high concentrations of FSH performed poorly on three-dimensional tests and tests of point localization. Men with low concentrations tended to perform better. Luteinizing Hormone (LH) tended to correlate positively with verbal/sequential skills and with two of the visuospatial skills for one session; testosterone was positively correlated with one spatial test. Multiple regression between the average performance on visuospatial tests and the three hormones produced Rs of 0.67 and 0.60, accounting for 39% and 29% of the variance, respectively, in Sessions 1 and 2. In women, the hormonal/behavior relationships were less clear although in many ways similar. For example, FSH was negatively correlated with one visuospatial test but only after the effects of estradiol and progesterone were partialled out. FSH was positively correlated with word fluency as was LH. With respect to sex differences women were poorer than men on the visuospatial tests and better on verbal fluency which is consistent with women's generally higher FSH levels and the negative relationship between FSH and visuospatial skills and the positive relationship with fluency.
Adolescent↗
Changes in specialized cognitive function following changes in hormone levels.
Increase of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in men by injection of luteinizing hormone releasing hormone (LHRH) prevented improvement in a spatial orientation test relative to a placebo condition. By contrast, performance on a fluency task was significantly increased after LHRH injection relative to the placebo condition. These data support between-subject results where FSH was negatively correlated with visuospatial skills and positively correlated with fluency. There was no change in cognitive function in males following injection of testosterone. There were also no fluctuations in cognitive function that coincided with hormonal fluctuations of the menstrual cycle in women.
Adolescent↗
The cognitive laterality battery: tests of specialized cognitive function.
The Cognitive Laterality Battery of neuropsychological tests is described and normative data and statistics are presented. Selection of tests was based on converging evidence from studies on patients with unilateral cerebral lesions, complete forebrain commissurotomy, and on normal subjects suggesting that visuospatial skills are primarily related to the right hemisphere while verbal and sequential skills are primarily related to the left. Factor analyses confirmed the dichotomy of the test choices. It is suggested that test results on individuals be interpreted as a cognitive profile defining the relative performance of specialized functions rather than the relative right or hemisphere locations. Previous studies with the CLB are described.
Adolescent↗
Right hemisphere superiority in processing new symbols for arithmetic operators.
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Adolescent↗
Hemispheric asymmetry in fighter and helicopter pilots.
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Adolescent↗
Shift in cognitive asymmetries between wakings from REM and NREM sleep.
Twelve subjects were awakened from REM and NREM sleep and tested on three tests designed to measure functions attributed to the left cerebral hemisphere and three tests designed to measure right hemisphere function. A significant shift in cognitive profile was found in the direction of tasks attributed to left hemisphere performance following waking from NREM sleep relative to waking from REM sleep. These results are consistent with the observed reciprocal oscillations between left and right functions during the waking period and imply that performance of these specialized functions may be controlled by some of the same mechanisms that govern biorhythms.
Adult↗
Asymmetrical cognitive deterioration in demented and Parkinson patients.
Patients with Parkinson's disease and patients with dementia showed greater deterioration on functions attributed to the right cerebral hemisphere, than on functions attributed to the left. Relative to matched controls, Parkinson patients were significantly impaired on right hemisphere tests, but did not differ on left hemisphere tests. Demented patients were significantly deficient on all tests, but right decline was greater than left. Ninety-six patients were tested: 32 diagnosed as senile or presenile dementia, 32 Parkinson patients, and 32 non-neurological patients matched for age, sex and education. Functional performance was assessed by a battery of validated tests for left and right hemisphere cognitive functions. Patients were defined with two scores based on the results of the test: Cognitive Laterally Quotient (CLQ) reflecting the averaged performance on the left hemisphere tests, subtracted from the average performance on right hemisphere tests, and Cognitive Performance Quotient (CPQ), reflecting the total level of performance of both hemispheres. These measures defined a characteristic cognitive profile for each group.
Aged↗