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PubMed1983

Field dependency, n power and locus of control variables in alcohol aversion.

Male volunteer alcoholics (N = 47) were given I-E Scale, Embedded Figures Test and a newly devised n Power inventory in a 20-trials, 10-day electroconditioning aversion program. Some were given vodka, some preferred beverage, some both shock and covert sensitization. Follow-up was 2 months by interview, 6 months by letter, with combination therapy more effective. External control and field dependency were associated with being older. Internals and hard liquor drinkers tended to be abstinent for both periods as predicted. Field dependency was a more unstable variable for outcome. A non-preferred beverage generalizes to preferred beverage abstinence.

Adult↗
PubMed1982

Factors regulating drug cue sensitivity: the effects of dose ratio and absolute dose level in the case of fentanyl dose-dose discrimination.

This study presents a parametric analysis of the difference case in drug discrimination; rats were trained to discriminate a higher training dose of fentanyl, a narcotic analgesic, from a lower dose. Two parameters of dose-dose discrimination were investigated. First, dose ratio indicates the magnitude of the difference, expressed as a ratio, between the higher and the lower of the two training doses; dose ratios were 2, 4, 8, and 16 in four groups of animals. The second parameter is the absolute level of fentanyl dose at which any given ratio can be discriminated; in all four groups, the higher of the two training doses was progressively lowered from 0.04 to 0.00125 mg/kg. It was found that dose-dose discriminability of fentanyl was proportional to dose ratio in the entire 2 to 16 range of dose ratio, and that discriminability decreased monotonically as the absolute dose level was lower. Bias in discriminative responding was determined by absolute dose level only; dose ratio exerted no effect. The slope of the fentanyl generalization gradient increased as the dose ratio was smaller, and decreased as the absolute dose level was lower. Both dose ratio and absolute dose level also exerted effects on the ED50-value, but the effects of dose ratio were apparent only at higher training doses of 0.04 to 0.01 mg/kg. The data are consistent with the suggestion that fentanyl-saline discrimination is a special case of dose-dose discrimination; it is similar to the case where the higher of two training doses differs about 16-fold from the lower one. At this point, the lower training dose produces only liminal effects.

Animals↗
PubMed1982

Discrimination of facial expressions by preschool children.

This study investigated preschool children's ability to discriminate and categorize facial expressions. Children were shown drawings of persons with expressions of joy, sadness, surprise, and anger and asked to choose from an array of drawings the face that felt "the same" as the standard. The choice array varied on 1 or more features of the standard's expression or had identical key facial elements. In some cases the match had identical facial features and in others the match was a generalized version with no identical features. Children were given various prompts to select the accurate match for the standard. Both with and without prompts children made fewer errors matching happy expressions and matched generalized happy expressions as accurately as identical expressions. Surprised and angry faces were less accurately matched. Providing verbal labels for the faces facilitated matching, particularly for happy and generalized expressions, suggesting that labeling or explicitly providing a conceptual category may aid comparison and/or memory of the expressions. A levels-of-processing effect is suggested to be operating in young children's discrimination and categorization of facial expressions.

Anger↗
PubMed1982

[Role of the frontal cortex in the differentiation of conditioned stimuli].

Unrestrained cats were trained for a two-side choice of alimentary reinforcement in response to one of two initial figures differing in size (larger--smaller). Subsequently, new tasks were presented with the same alternative: differentiation of geometric figures, contour pictures, differentiation of the number of stimuli (two or five asterisks), abstraction from present signals (tasks with temporal extrapolation) a. oth. It has been shown that ablation of the proreal gyrus does not affect simple forms of generalisation, but excludes detection of a quantitative parameter and disturbs elementary abstract thinking.

Animals↗
PubMed1980

[Supersensitivity by reserpine and means of antagonizing it].

Single or repeated reserpine application elicited in rats a supersensitivity which is measurable both by the rotation behavior and motor activity. This supersensitivity is accompanied by enhanced responsiveness to unspecific stimuli and increased responsiveness to receptor-active substances (dopamine, noradrenaline, serotonin, carbachol). Pretreatment with actinomycin D can transiently inhibit the development of supersensitivity, while repeated lithium application has no effect on it. The results give evidence for the unspecificity of reserpine-induced supersensitivity, which comprises both aminergic transmission systems and cholinergic systems and can be antagonized by inhibitors of protein synthesis.

Animals↗
PubMed1980

The feature-positive effect in adult human subjects.

Previous experiments with animals and young children have shown that discriminations based on the presence versus absence of a single feature are learned more easily when the feature appears on reinforced rather than nonreinforced displays. Six experiments demonstrated an analogous effect in college students, across a range of stimulus materials, general procedures, kinds of feedback, pacing of trials, and instructions to the subject. The results were analyzed in terms of the exceptionally strong control of behavior by events that are present on positive trials. These findings have implications for theoretical interpretations of human concept learning and decision making, and offer additional examples of the difficulty organisms experience in using "nonoccurrence" as a cue.

Concept Formation↗