Search PubMed⌕ Search

Biomedical subjects

M Galizio

Publications and source records attributed to M Galizio.

27 records · Page 2Linked to original sources

Sensation seeking, reinforcement, and student drug use.

College student volunteers completed the Sensation Seeking Scale, a drug use survey, and provided demographic information. Subjects were also asked to generate a list of the events that they found most reinforcing (Reinforcer List). Drug use was positively related to scores on all subscales of the Sensation Seeking Scale. Although neither drug use nor sensation seeking scores were related to the total number of items generated on the Reinforcer List, drug users did generate a higher percentage of items rated as high sensation producing items, and percent high sensation reinforcers was correlated with scores on the Sensation Seeking Scale. These results illustrate the importance of the sensation seeking motive as a correlate of student drug use.

Adult↗

Sensation seeking and drug choice.

Sensation Seeking Scale scores were obtained from two groups of drug program clients: polydrug users and opiate and depressant drug users. The major findings were that polydrug users scored higher in sensation seeking than depressant users, and that this effect was independent of demographic differences between groups. These results suggest that the sensation-seeking motive may be a significant factor for polydrug, but not depressant, abuse patterns.

Adult↗

Conditional gradient displacements: the effects of conditional discrimination training on human auditory frequency generalization.

The effects of conditional discrimination training on human auditory frequency generalization were examined. In Experiment 1 subjects learned to press a key to one tone, but not to a higher pitched tone when presented in the left earphone, and to respond to the higher pitched tone but not to the lower tone in the right earphone. Generalization tests revealed conditional peak shifts, with subjects responding to frequencies lower than the positive stimulus (S+) for left-earphone presentations and to frequencies higher than S+ for right-earphone presentations. The shifts observed following conditional discrimination were larger than those obtained from subjects who received simple discrimination training. Experiment 2 showed that these larger shifts were not simply due to extended discrimination training. In Experiment 3 subjects were trained with conditional discriminations involving an S+ and a negative stimulus (S-) in one earphone but only a single, positive stimulus in the other earphone. These subjects also showed conditional gradient shifts with displacements in both directions. The occurrence of peak shift without an S- can only be interpreted as involving relational responding.

Adolescent↗

Contingency-shaped and rule-governed behavior: instructional control of human loss avoidance.

Instructions can override the influence of programmed schedules of reinforcement. Although this finding has been interpreted as a limitation of reinforcement schedule control in humans, an alternative approach considers instructional control, itself, as a phenomenon determined by subjects' reinforcement histories. This approach was supported in a series of experiments that studied instructional and schedule control when instructions either did or did not accord with the schedule of reinforcement. Experiment I demonstrated that accurate instructions control discriminative performances on multiple avoidance schedules, and that such control persists in a novel discrimination. Experiments II and III showed that elimination of instruction-following occurs when inaccurate instructions cause subjects to contact a monetary loss contingency. Experiment IV demonstrated the reinforcing properties of accurate instructions. Skinner's view of rule-governed behavior is consistent with these findings, and can be extended to account for many aspects of instructional control of human operant behavior.

Journal Article↗

Chained schedules of avoidance: Reinforcement within and by avoidance situations.

Four rats were exposed to chained schedules with variable-cycle avoidance in both links. Responding in the initial link cancelled shocks scheduled once per minute and, according to a conjoint fixed-ratio schedule, produced a terminal link where scheduled shock rates varied from 0 to 8 shocks per minute in different conditions of the experiment. Response rates in the terminal link increased as a function of the scheduled shock rate. Response rates in the initial link, on the other hand, decreased as a function of the shock rate actually received (rather than scheduled) in the terminal link. While consistent with other studies of aversive control, these results differ from those obtained in chained schedules of positive reinforcement in that increases in reinforcement within the terminal link of the chain did not systematically increase the reinforcing value of that link.

Journal Article↗

Semantic representations of drug terms by industrial workers.

Studied semantic representations of drug terms as a function of reported use of illicit drugs, with young-adult industrial workers as the Ss (college students served in a preliminary study). Procedures for describing semantic organizations included the semantic differential, similarity ratings, sorting, and verbal production of drug names. In general, structured representations of drug terms were produced, in line with the categories: illicit drugs, medicinal drugs, alcohol products, and substances containing nicotine or caffeine. Increased drug use was accompanied by more positive evaluations of illicit drugs on the semantic differential and more extensive clustering on the verbal production task. It was concluded that use of illicit drugs is accompanied by distinctive semantic representations, that these patterns mainly involve drugs used illicitly, and that they are most apparent on tasks in which responses are least constrained, such as verbal production.

Adult↗

Clock control of human performance on avoidance and fixed-interval schedules.

The avoidance and fixed-interval performances of human subjects were studied in two experiments. Addition of time-correlated stimuli (added clock) improved behavioral efficiency, since response rates decreased without decreases in reinforcement rates. Response-dependent display of the clock maintained a second, observing response and reductions in clock duration weakened such observing behavior. Generally, the reinforcing properties of the clock were more apparent with the avoidance than with the fixed-interval schedule, a finding attributed to temporal cues already provided by delivery of the fixed-interval reinforcers. Reduced rates of the main response when the clock was dependent on an observing response were more than offset by rates of the observing response in the majority of subjects. Thus, the results do not support an interpretation of the reinforcing properties of added clocks simply in terms of work reduction.

Journal Article↗

The effects of ethanol and naloxone on extinction of jump-up avoidance performance in rats.

The present study assessed the effects of ethanol and naloxone on the extinction of a jump-up avoidance response in Sprague-Dawley rats. Rats were first trained to jump onto a shelf to escape or avoid shock (0.5 mA). Upon reaching an acquisition criterion of 8 consecutive avoidance trials, animals were removed from the apparatus and exposed to 1 of 4 doses of ethanol (0, 1.0, 2.0, or 2.5 g/kg), and either naloxone (3 mg/kg) or saline. Rats were then returned to the conditioning apparatus with the shock turned off, and resistance to extinction was assessed. Ethanol had biphasic effects with low doses (1 g/kg) facilitating, and higher doses (2 and 2.5 g/kg) suppressing number of extinction responses by comparison to controls. Naloxone did not influence the course of extinction, and did not reverse any of the effects of ethanol. These results did not support the hypothesis that the effects of ethanol on aversively-motivated behavior are opioid-mediated.

Animals↗

Effects of ethanol and naltrexone on aggressive display in the siamese fighting fish, Betta splendens.

The present study used the aggressive display of Betta splendens in response to a mirror as an index of the effects of ethanol and the opiate antagonist, naltrexone. Naltrexone produces an opiate receptor blockade and thus provided a test of the hypothesis that ethanol effects on aggression are mediated by the opioid system. Eighty fish were randomly assigned to one of eight groups in a 4 X 2 factorial design with Ethanol (0, 0.25, 0.50, and 0.75 g%) and Naltrexone (0 and 5 mg/l) as the main factors. The 0.75 g% dose of ethanol reliably suppressed aggressive display as measured by number of gill show responses, but lower doses had no effect or tended to increase aggressive display. At the same time, all doses of ethanol increased arousal in the fish as measured by airgulping. Naltrexone alone did not have effects on aggression or arousal, and did not interact with ethanol on either measure. Thus the results did not support the ethanol-opioid common-link hypothesis.

Aggression↗