Stimulus- or response-induced excitation. A comparison of the behavior of introverts and extraverts

The tendency to inspect visual material (slides) rather than to respond by pressing a key in an attempt to move on to the next slide, was compared among introverts and extraverts. As predicted from Brebner and Cooper (1974): (1) extraverts inspected the stimuli for a shorter time before making their first response, (2) extraverts made more responses at a faster rate than introverts did, and (3) extraverts produced a significantly higher proportion of runs of accelerating responses.     

Interpersonal attraction and person perception: Two tests of three balance models

Two experiments tested the adequacy of three balance models (equal-weights tetrahedron model, unequal-weights tetrahedron model, Feather model) for the p?o?x triad. In the first experiment, involving a variation of Byrne's anonymous-stranger technique, a PDP-11 computer was used to provide feedback on five attitude issues for each of the cells of a design created by five levels of the p?x variable (?2, ?1, 0, +1, +2) and five levels of the o?x variable (?2, ?1, 0, +1, +2). The dependent variable was p?o, interpersonal attraction. In the second experiment there were five-level manipulations of both p?x and o?p with an o-x (person perception) dependent variable. The correlations between obtained results and the predicted values for each of the three models were quite high (.64, .65, .61, respectively, in the first experiment and .60, .59, and .58, respectively, in the second), but the Feather model was judged least adequate. The data in the first experiment were best described by the unequal-weights tetrahedron model, and the data in the second experiment were best described by the equal-weights tetrahedron model. It was argued that avoidance of mutual dislike was responsible for the relatively greater support for the unequal-weights than equal-weights tetrahedron model in the first experiment.     

Intelligence and teachers' ratings as predictors of abstract and concrete learning

This study concerned the prediction of children's learning with an individual measure of intelligence and teachers' evaluations. Eight abstract and eight concrete nouns were paired with nonsense geometric figures and presented to 60 elementary school children in a three-trial paired-associate (PA) learning task. Subjects' IQ scores on the Wechsler Intelligence Scale for Children-Revised and teachers' ratings of learning proficiency were used to predict children's performance on the PA task. Multiple correlations favored abstract learning with verbal scale intelligence, accounting for the majority of the variability. Teachers' ratings provided a surprising degree of predictive efficiency for abstract recall which was redundant with verbal intelligence.     

The modification of intelligence through early experience

Infants judged to be at risk for subnormal intellectual growth were randomly assigned to an Experimental (N = 27) or a Control (N = 25) group. Infants in both groups received medical care and dietary supplements; their families received social work services on a request basis. Experimental children participated in an educational daycare program beginning before the third month of life. The daycare program was composed, in part, of curriculum activities designed to stimulate intellectual growth. Between 6 and 36 months of age, Experimental children maintained normal intellectual growth; Control children declined in IQ beginning between 12 and 18 months of age and remained significantly lower than Experimental children at 24 and 36 months. The mother-child IQ correlation for Control dyads was 43; for Experimental dyads the correlation was ?.05. These two types of evidence are interpreted as support for the importance of early environments in the development of intelligence.     

Reactions to receiving expected and unexpected help from a person who violates or does not violate a norm

Different factors may affect reciprocity and attraction to an aid-giver. Sixty white South African high school students participated in a “record contest”. Hints provided by the quizmaster enabled them to win a prize. His help was expected or unexpected and, in providing this help, the quizmaster either did or did not violate a specific norm against doing so. It was predicted that recipients of unexpected help would display more reciprocity than recipients of expected help, but that the aid-giver would be derogated only when he behaved in both an unexpected and counternormative way and that, in general, attraction and reciprocity would be unrelated. These hypotheses were supported. They suggest that reciprocity is normally not mediated by attraction and that neither expectancy violation nor counternormative behavior will be itself produce derogation of an aid-giver. They further suggest recipients of unexpected help probably feel more obliged to repay an aid-giver than do recipients of expected help.     

An experimental analysis of social traps

Social traps, such as the overgrazing of pasturelands, overpopulation, and the extinction of species, are situations where individuals in a group respond for their own advantage in a manner damaging to the group. A laboratory analog was devised to simulate conditions that produce social traps. The traps were constructed by superimposing schedules of reinforcement. Single responses were followed by multiple consequences which were opposite in valence, with the negative consequence delayed. Subjects in groups of three could respond individually for points that applied toward class credit. Each ten presses of a button added one point to the subject's total and subtracted one point from a common pool. The pool was replenished with points at fixed rates. If subjects responded for points faster than the replenishment rates, the pool would empty and the experiment would terminate before subjects could accumulate maximum credit. In addition, the maximum pool size and the ability to communicate were varied. Main effects were found for both, which indicated the least effective resource management occurred when the pool was small and no communication allowed. An analysis of cumulative records showed differing response patterns across conditions.     

Differential acquisition of conditioned suppression in rats with increased and decreased luminance levels as CS + s

Using a conditioned suppression procedure, it was demonstrated that suppression of responding was substantially enhanced when the CS signaling the occurrence of shock was an increment in luminance level (bright CS), relative to an equivalent decrement in luminance level serving as a signal for shock (dim CS). The results of a pseudoconditioning control procedure illustrated that the differential effectiveness of the bright and dim CSs was dependent upon explicit CS-US pairings. The bright and dim stimuli were found to produce equivalent rates of conditioning when they were used to signal the availability of reinforcing stimuli in an appetitive discrimination procedure. The interpretation considered to be most consistent with the data is associative in nature; rats may be brought into the experimental setting prepared to associate bright light with danger and contraprepared to associate dim light with danger.