Kim W. Schaeffer
University of Oklahoma Health Sciences Center
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Featured researches published by Kim W. Schaeffer.
Alcohol | 1987
Bradley W. Patterson; Harold L. Williams; Garnet A. McLean; Landgrave T. Smith; Kim W. Schaeffer
In a dual-modality paradigm, visual and auditory event-related potentials were elicited in 40 alcoholic men and 30 controls, equated with the alcoholics on age and education. Half of each group had first-degree relatives who were alcoholic (family history positive). The amplitude of the visual N1 component was reduced among the alcoholics, but their auditory N1 amplitudes were normal. Average N1 amplitudes were also smaller in the family history positive subjects but this effect was significant only for auditory stimuli. Alcoholics showed reduced average P3 amplitudes to both visual and auditory signals, particularly in the family history positive group. Clearly, stratification by family history is useful for ascertainment of ERP variation among alcoholics. There were no effects on P3 latency. Among several possible explanations of P3 deficits in alcoholics, two are particularly interesting: (1) alcoholics cannot mobilize sufficient processing resources in the service of effortful cognitive functions; (2) alcoholics, being poorly motivated, apply insufficient effort to cognitive tasks. An experiment designed to test these hypotheses is described.
Addictive Behaviors | 1990
Oscar A. Parsons; Kim W. Schaeffer; Susan Wagner Glenn
The prediction of resumption of drinking in posttreatment alcoholics was investigated as a function of five possible confounding variables: depression, anxiety, childhood symptoms of attention deficit and conduct disorders and family history of alcoholism. Male and female detoxified alcoholics (n = 103) in inpatient treatment programs were administered a neuropsychological battery and retested as outpatients 14 months later; peer nonalcoholics (n = 73), given the same battery, had a similar interest interval. Alcoholics who resumed drinking (N = 41) performed significantly poorer on an overall neuropsychological performance index than abstainers (N = 62) who performed significantly poorer than nonalcoholics. Stepwise multiple regression equations using the variables noted above revealed that depressive symptoms, ADD and the performance index were the only variables to enter the prediction (R2 = .26, p less than .001); depression accounted for most of the variance. At retest all three groups improved significantly, but not differentially, and were as significantly different at retest as at initial testing. Implications of these results are discussed.
International Journal of Neuroscience | 1988
Kim W. Schaeffer; Oscar A. Parsons
The performance deficits of alcoholics on tests of learning and memory are typically attributed to cognitive impairment. This study tests an alternative hypothesis that the deficits are due to motivational impairment. A face-name learning and memory test was administered to 30 sober male nonalcoholic and 40 alcoholic subjects in a 2 x 2 [Group (alcoholic, nonalcoholic) x Monetary incentive (incentive, no incentive)] between-subjects design. The monetary incentive was made contingent upon performance. Alcoholics required significantly more trials to learn face-name pairs, and they recalled fewer face-name pairs at the delayed recall. Incentive subjects manifested a trend toward impairment on the trials-to-learn measure. However, there were no significant Group x Incentive interactions in learning or memory, or on a self-report questionnaire of subjective states (e.g., effort expended) experienced during the test. Thus, no evidence was found to support the impaired motivation hypothesis; the cognitive hypothesis remains as the most credible hypothesis to account for the performance deficits of alcoholics.
International Journal of Neuroscience | 1989
Bradley W. Patterson; Rajita Sinha; Harold L. Williams; Oscar A. Parsons; Landgrave T. Smith; Kim W. Schaeffer
The relationships between event-related potential (ERP) measures and neuropsychological measures were investigated in a group of 39 male alcoholics and 22 age-matched male controls. Late component ERP measures such as N1, Nd, and P3 components and neuropsychological measures of perceptual-motor function, semantic and figural memory and verbal abstracting functions were included in a correlational analysis. No significant correlations between N1 amplitude or latency and neuropsychological tests were obtained. However, visual Nd amplitude correlated significantly with perceptual-motor tests and figural memory scores in the alcoholics. Significant correlations were found in alcoholics for visual P3 amplitude at PZ and delayed figural memory scores and two of the perceptual-motor tests. No significant correlations were obtained among the controls. These data indicate that significant relationships exist between some neuropsychological and ERP measures but that these relationships are restricted to measures of perceptual-motor functioning and to delayed figural memory.
Applied Neuropsychology | 1995
Sara Jo Nixon; Oscar A. Parsons; Kim W. Schaeffer; Robert L. Hale
In Study 1, 430 sober male alcoholics and 98 nonalcoholics completed the Shipley Institute of Living-Vocabulary (SILS-V) and Abstraction (SILS-A) under the standard instructions. Alcoholics performed significantly more poorly than the nonalcoholics on SILS-A. High test-retest reliability of the SILS with a 2-week interval between testings was obtained. Item analysis of the 20-item SILS-A revealed that only items 4-14 discriminated alcoholics and controls, six items required reversal of a cognitive set (reversal) and five did not (nonreversal items). Exploratory factor analyses confirmed essentially the same division of items. In Study 2, two 10-item forms of SILS-A equated for difficulty level and reversal-nonreversal cognitive demands were administered to 186 male and female college students. Results indicate the two forms are equivalent in difficulty, demonstrate no gender differences and correlate significantly with cumulative college grade point averages.
Alcoholism: Clinical and Experimental Research | 1984
Kim W. Schaeffer; Oscar A. Parsons; J. Robert Yohman
Journal of Nervous and Mental Disease | 1987
Kim W. Schaeffer; Oscar A. Parsons
Journal of Consulting and Clinical Psychology | 1988
J. Robert Yohman; Kim W. Schaeffer; Oscar A. Parsons
Journal of Nervous and Mental Disease | 1988
Bradley W. Patterson; Oscar A. Parsons; Kim W. Schaeffer; Austin L. Errico
Archives of Clinical Neuropsychology | 1988
Mark Allen Everett; Kim W. Schaeffer; Oscar A. Parsons