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V DeNoble

Publications and source records attributed to V DeNoble.

5 recordsLinked to original sources
PubMed1981

Methohexital-reinforced responding in rats: effects of fixed ratio size and injection dose.

The rate and pattern of lever pressing were studied in nine rats during daily 6-hr sessions in which responding led to the i.v. injection of sodium methohexital. Level pressing was shown to be established and maintained by the response-drug contingency in the absence of physiological dependence or aversive stimulation. Effects of 1.0, 2.0, 3.0 and 4.0 mg/kg/injection of methohexital and fixed ratio schedules of 1, 5, 10, 15 and 20 responses per injection were determined on response rate and drug intake. At 1.0, 2.0 and 3.0 mg/kg/injection, increases in fixed ratio value produced systematic decreases in drug intake; the magnitude of the effect was dose-dependent. More total drug was taken at each fixed ratio value as injection dose was increased. At 4.0 mg/kg/injection, drug intake remained relatively stable over 1, 5, 10 and 15 responses per injection, and decreased at 20 responses per injection. Response rate was inversely related in injection dose at 1 and 5 responses per injection and directly related to injection dose at 15 and 20 responses per injection.

Animals↗
PubMed1977

Changes in fixed-ratio performance and blood alcohol levels in monkeys.

Three female Bonnet monkeys prepared with indwelling venous catheters were maintained on a fixed-ratio schedule of food reinforcement until response rates were stable. The animals were then intubated with alcohol (5.0 g/kg) 30 min prior to testing. Blood alcohol concentrations (BACs) were determined every 15 min throughout the 90-min session. Each alcohol intubation was separated by 3 days and on the second control day an isocaloric sucrose solution was intubated. The results show that the alcohol-induced response suppression gradually returns to baseline levels after 5 alcohol intubations, and the BACs were concomitantly decreased. The results indicate that the reversibility of alcohol induced behavioral impairments and changes in BACs develop within similar temporal intervals.

Animals↗
PubMed1977

Enhanced response acceleration or suppression produced by response-independent food presentations in rats with septal lesions.

In two separate experiments, the response rates of rats with septal lesions were compared with those of control rats when response-independent food was presented while subjects were responding on a differential-reinforcement-of-low-rate schedule of reinforcement (Experiment 1) or according to a conjunctive differential-reinforcement-of-high-rate, fixed-ratio schedule (Experiment 2). Free-food deliveries resulted in acceleration of responding of subjects working on the low-rate schedule and in suppression of responding of those animals working on the high-rate schedule. Both of these effects were localized to a brief time period immediately following the free-food deliveries, and baseline rates of responding were not altered. The acceleration and suppression of responding that occurred on the respective schedules were greatly enhanced in rats with septal lesions. This finding supports the suggestion that these animals are hyperreactive to the reinforcing and/or eliciting properties of discrete stimulus events.

Animals↗