Event-related brain potentials in boys at risk for alcoholism.

Recent neurophysiological findings have demonstrated that abstinent chronic alcoholics manifest deficits in event-related brain potentials. To explore possible biological antecedents of alcoholism the present study examined boys at high risk for alcoholism. Event-related brain potentials were recorded from biological sons of alcoholic fathers and matched control boys. Differences in the P3 component of the potentials were obtained between the high-risk and control subjects.

Evoked potential correlates of expected stimulus intensity.

The electrophysiological responses to a flash of medium intensity have different wave shapes in trials in which the occurrence of bright stimuli or dim stimuli is expected. When a bright or dim stimulus is signaled, the potentials evoked by the medium stimulus resemble the responses evoked by a real bright or dim flash.

Biological investigations in alcohol research.

The biological mechanisms examined in this paper cover only a small portion of those that may be involved in the pathogenesis of alcoholism. Certain areas on which a great deal of work has already been done have been entirely omitted. Among these are studies on brain acetylcholine and gamma-aminobutyric acid metabolism in alcohol-related conditions; the effect of alcohol on brain proteins and nucleotides and the relationship of changes in these to the development of tolerance and physical dependence; and a variety of other areas involving biochemical and physiological parameters. The omission of any of these areas in no way suggests that they are less significant than those that have been covered. It is just that I have attempted to present a cohesive and coherent review of some areas of biological research which thus far appear to throw light on the clinical development and phenomenology of the alcoholism syndrome. In order to present such a thesis, I have inevitably crowded the evidence to fit some of my pet hypotheses. However, in controversial areas (which are many), I have tried to present some of the evidence on both sides and, hopefully, have succeeded in offering a fair overview of the state of the science as it exists today.

Neurochemical correlates of alcohol preference in inbred strains of mice.

C57B1/6J, a specific inbred strain of mice with high alcohol preference and DBA/2J, a specific inbred strain with poor preference for alcohol were studied. Brain content of acetylcholine, uptake of 14C-Choline by whole brain homogenate were significantly higher in the C57B1/6J mice whereas brain acetylcholinesterase was higher in the DBA/2J mice. No significant difference was found for the level of brain serotonin, uptake of 3H-norepinephrine or 3H-dopamine. Treatment with a specific inhibitor of choline transferase, 4-(1-napthylvinyl) pyridine salt (10 mg/kg, twice daily) shifted the selection of alcohol to water in the C57B1/6J mice. These findings suggest a direct involvement of central cholinergic mechanism in alcohol preference.

Event-related brain potentials to high incentive stimuli in abstinent alcoholics.

We have previously found that the P3 component of the event-related potential (ERP) is reduced in alcoholics in visual target-selection paradigms. P3 voltage depends on the "subjective significance" of the stimulus (e.g., task relevance, probability of occurrence, motivational factors). We were interested in assessing P3s in alcoholics to motivationally significant stimuli that did not differ with respect to other aspects of significance. Equiprobable, task-relevant visual stimuli with different acquired incentive values were presented to alcoholics under baseline and two incentive conditions. Alcoholics manifested similar lower P3 voltages without P3 latency delays to all stimuli, regardless of incentive values. Latency Corrected Averages indicated that these results were not due to latency jitter in the averages. These results suggest multiple system deficits in alcoholics, perhaps in involving frontal and/or medial temporal lobe, the brain sources implicated in the generation of P3. Our results perhaps reflect a deficit in motivational-cognitive systems in alcoholics, possibly affecting their ability to actively sustain information processing.

Oral cytologic patterns and nutritional status: some relationships in alcoholic subjects.

Exfoliative cytologic preparations from the cheeks of 790 alcoholic patients were evaluated for relationships between microscopic features and selected indicators of nutritional status. Significant associations were observed between the cell/nucleus ratio, degree of cornification, relative concentrations of leukocytes and microorganisms, and poor dietary patterns, as well as body weight statua and serum albumin and blood hemoglobin levels. Microscopic examination, as an adjunct to gross inspection of the mouth, may be of value in the clinical assessment of nutriture.

Oral cytologic patterns in relation to smoking habits. Some epithelial, microfloral, and leukocytic characteristics.

Papanicolaou smears from the cheeks and tongues of 790 alcoholic patients were evaluted for possible associations between cytologic features and cigarette consumption. The findings appear consonant with the view that microscopic changes are frequent in clinically unremarkable areas of the mouth and that tobacco induces some of the cellular changes to which its use has been clinically and epidemiologically related.

The N2 component of the event-related brain potential in abstinent alcoholics.

The latencies of the N2 component of the ERP and reaction time were manipulated in abstinent alcoholics and controls. The experimental design consisted of visual stimuli that differed in difficulty of discrimination. N2 latencies were found to be significantly delayed in alcoholics compared to controls, particularly for the easy discrimination. While controls manifested significantly earlier N2 latencies for the easy discrimination compared to the difficult discrimination, alcoholics did not manifest any significant difference in the latency of N2 as a function of the level of difficulty. There were no significant differences between groups in terms of RT or number of errors. In addition, alcoholics displayed significantly reduced P3 amplitudes to target stimuli compared to controls. These results suggest that match/mismatch processes are impaired in alcoholics and that they have difficulty evaluating the potential significance of a stimulus.