Lelon J. Peacock

Acute alcohol intoxication and female orgasmic response

Abstract This study tested the hypothesis that increasing levels of acute alcohol intoxication are related to systematic changes in female orgasmic experience reflected by physiological, behavioral, and cognitive indices. Using a repeated measures design with monthly experimental sessions, each of 18 university women were sustained at four different blood alcohol concentrations (BAC) in counterbalanced order prior to viewing sexually explicit videotapes and engaging in masturbation to orgasm. Measures of vaginal blood volume obtained by means of a vaginal photoplethysmograph and complemented by a behavioral latency measure showed a progressive and systematic depressant effect of alcohol on orgasmic responding. Higher BACs were associated with longer orgasmic latencies and decreased subjective intensity of orgasm, while, paradoxically, women reported significantly greater sexual arousal and orgasmic pleasurability under conditions of moderate and high alcohol intoxication. Results have implications for tre...

Disruption of a radiation-induced preference shift by hippocampal lesions

Abstract Male rats with extensive hippocampal lesions, in contrast to control rats, continued to exhibit a strong preference for a saccharin solution after saccharin ingestion was paired with exposure to low level X-irradiation. The results suggest that the hippocampus mediates, in part, the motivational consequences of exposure to X-radiation.

Taste aversion and passive avoidance in rats with hippocampal lesions

Rats with near total hippocampal lesions were compared with cortical and normal control animals on taste aversion and passive avoidance conditioning. While the initial magnitude of the taste aversion induced through illness was not significantly affected by hippocampal ablation, the aversion did extinguish more rapidly in experimental animals. Locomotor passive avoidance was significantly impaired by the lesion.

Conditioned taste aversion as a function of age in mature male rats

Experimental groups of young mature (90-120 days), mature (365-395 days), and aged (730-760 days) Fischer-344 rats were allowed to drink a saccharin solution followed by lithium chloride toxicosis initiated at one of three intervals, either 15, 60, or 240 minutes. Control groups were given saline placebos according to the same schedule. In a preference test conducted 48 hours after conditioning, there was little evidence of age differences in the acquisition of a saccharin aversion. Age differences were noted in the extinction of the aversion which was tested by monitoring preference over a period of 32 days of continuous access to saccharin and water. Older animals tended to show greater resistance to extinction.

Feeding regime affects activity-stress ulcer production.

Rats were divided into either an active group housed in activity wheels or a control group housed in stationary laboratory cages. Both active and control groups were further divided into groups receiving 1, 2, 3, or 4 meals daily for a total feeding time of 1 hr. Control rats were food-yoked to active animals. Results indicated that active rats fed 1 meal daily developed significantly more ulceration, lost more weight, and consumed less food and water than other groups. The number of daily meals had no effect on the amount of activity. No control animals developed ulcers, although they received the same amount of food. These results suggest that frequent feedings mitigate gastric peptic ulcer formation in rats placed in the activity-stress ulcer paradigm.

Taste-aversion conditioning in rats with septal lesions

Two experiments were conducted to assess the effects of lesions in the septal forebrain area of rats on the development and maintenance of a radiation-induced taste aversion. While the lesioned animals were found to drink more of the fluid used as a conditioned stimulus during X-radiation, no effect of the lesion on subsequent aversion to the stimulus was found. The data further restrict the generality of viewing the function of the septal forebrain area as inhibitory.

Acoustic Startle Eyeblink Response After Acute Exercise

The acoustic startle eyeblink response (ASER) is a useful probe for investigating central nervous system activity associated with emotional responses to aversive and appetitive stimuli. Though the ASER is sensitive to change in emotional arousal, the effect of acute physical exertion on ASER has not been reported. We examined changes in ASER amplitude and latency in 26 healthy young men (24 ± 5 yr) after 20 min of cycling at light and hard intensities (40% and 75% VO2peak) and after 20 min of quiet rest. Mixed model ANCOVA, controlling precondition scores, indicated no effects for ASER amplitude or latency in either sedentary or active participants (p >. 10). Our findings indicate that possible effects of acute exercise on potentiated startle or ASER responses elicited by positive or negative foreground stimuli should not be expected to be confounded by an altered baseline acoustic startle eyeblink response when measured in healthy young men.

Kainic acid stimulation of the lateral septum elicits tachycardia

Electrical stimulation of the lateral septum results in a transient cardiodeceleration which may represent parasympathetic rebound to a brief sympathetic activation. Kainic acid (KA) is a potent neuronal excitant. Stimulation of the lateral septum by KA produced a short-latency tachycardia. Vehicle injections, as well as KA administration to adjacent structures, did not effect significant changes in heart rate. Intraventricular KA, however, did result in a significant tachycardia. Knife cuts of the fornix, interrupting the glutamatergic innervation of the septum, completely blocked the cardiovascular response to KA. Pharmacological treatments reducing sympathetic activity prevented or reversed KA-elicited tachycardia. Thus, it appears that septal administration of KA produces sympathetic activation. KA may serve as a useful tool in studies assessing central regulation of the autonomic nervous system, and the interrelationship between autonomic activity and seizure-induced neuronal loss.

General activity in hamsters with septal lesions

Abstract The general activity of septal-lesioned and control male golden hamsters was measured pre- and post-operatively with the ultrasonic device. Increased activity following the lesion was found during dark, but not light hours. The lesion did not appreciably alter the hourly activity rhythm.

Interval Histogram Analysis of Eeg Hemispheric Activity In Schizophrenia

While research into the psychophysiological correlates of maladaptive behavior has expanded during recent years, the investigation of the hemispheric processes related to psychopathology has experienced unprecedented growth during the last few years (e.g., Flor-Henry, 1979). One particular branch of this type of hemisphericity research which has received considerable attention and yielded results of heuristic value has been the study of hemispheric activity in schizophrenics, see Flor-Henry, Koles & Reddon (this volume); Flor-Henry & Koles (1984); Newlin, Carpenter and Golden (1981) and Walker, Hoppes and Emory (1981) for comprehensive reviews on this subject.