Observational learning of two visual discriminations by pigeons: a within-subjects design.

Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.     

DOES EFFORT PLAY A ROLE IN THE EFFECT OF RESPONSE REQUIREMENTS ON DELAYED MATCHING TO SAMPLE?

The possible role of "effort" in the accuracy of pigeons' performance on a delayed matching-to-sample procedure was investigated by examining the effects of response requirements that accompanied a trial-initiating stimulus and that accompanied a sample stimulus. In the first experiment, the effect of varying the size of a fixed-ratio requirement for responses during an initiating stimulus was compared to that of varying a similar requirement for responses during the sample stimulus. Accuracy increased reliably with increases in the ratio scheduled during the sample stimulus, but was not significantly affected by increases in the ratio scheduled on the key during the initiating stimulus. In another phase of Experiment 1, sample duration was held constant while the ratio requirement was varied during the initiating stimulus. Again, accuracy of matching to sample was not significantly affected by the size of the ratio scheduled during the initiating stimulus. Experiment 2 provided a systematic replication of these results in another group of pigeons and included a more detailed analysis of responding. These results support the view that increases in sample-response requirement facilitate accuracy of delayed matching by increasing the durations of exposure to the sample stimuli, and do not support a role of effort in the sample-response effect. In Experiment 3, the facilitative effect of responses on the sample but not of those on the initiating stimulus was replicated using a simultaneous matching-to-sample procedure. This finding provides further evidence against an interpretation of response-requirement effects that appeals to effort; the finding also suggests that sample exposure might affect initial discrimination of the sample rather than remembering the sample.     

Comparing the effects of two correction procedures on human acquisition of sequential behavior patterns

Thirty-one college undergraduates learned to touch abstract stimuli on a computer screen in arbitrarily designated “correct” sequential orders. Four sets of seven stimuli were used; the stimuli were arrayed horizontally on the screen in random sequences. A correct response (i.e., touching first the stimulus designated as first) resulted in that stimulus appearing near the top of the screen in its correct sequential position (left to right), and remaining there until the end of the trial. Incorrect responses (i.e., touching a stimulus out of sequence) terminated the trial. New trials displayed either the same sequence as the one on which an error had occurred (same-order correction procedure), or a new random sequence (new-order correction procedure). Whenever all responses occurred in the correct sequence, the next trial displayed a new random sequence. Each phase ended when five consecutive correct response sequences occurred. Initially, the same-order correction procedure increased control by the position as well as by the shape of the stimuli; also, it produced more errors, more total trials, more trials to mastery, and more individual patterns of reacquisition than were produced by the new-order procedure.     

Of beasties and butterflies: Evidence for the stability and domain-specificity of individual differences in categorization

Previous research has failed to demonstrate unambiguously the relative stability across time and consistency across tasks of individual differences in categorization, or categorization breadth The present study of categorizing behavior in college students assesses breadth at each of four points in time over a six-week period Results are consistent with an interpretation of breadth as a highly stable individual difference variable, but one that is constrained by the nature of the stimulus sets employed High stability coefficients were observed for each of two redundant tasks In contrast, cross-task consistency indices were generally low Personality correlates of breadth were similarly weak and inconsistent Several variables are suggested that may attenuate the generality of categorization breadth The existence of multiple styles of categorization is discussed     

Sex typing and division of labor as determinants of marital change across the transition to parenthood

This investigation examines the proposition that wives who describe their personality in ways that deviate from sex stereotypes will become less positive and more negative about their marriage from before to after they become mothers, particularly when the transition to parenthood is accompanied by an increase in the traditionalism of marital roles. Sixty-one couples were studied longitudinally from the last trimester of pregnancy through the third postpartum month. The wives completed the Personal Attributes Questionnaire (Spence & Helmreich, 1978), which measures the extent to which they ascribe personality attributes stereotyped as "masculine" (i.e., instrumental, agentic) and "feminine" (expressive, affectional) to themselves, and several questionnaires assessing the marital relationship at both times of measurement. Results revealed that the more division of labor changed toward traditionalism, the greater the decline in wives' evaluations of the positive aspects of marriage and that changes in wives' evaluations of both positive and negative aspects of marriage can be significantly predicted by the interaction of the wives' expressivity and changes toward increased traditionalism in division of labor. Additional analyses showed that wives who do not ascribe female sex-typed attributes to themselves (relative to those who see themselves in sex-stereotyped ways) are more apt to evaluate their marriage less favorably from before to after parenthood when roles shift toward greater traditionalism.     

Concordance between clinicians' and patients' ratings of anxiety and depression as mediated by private self-consciousness

This study assesses the relations between the ratings of clinicians and psychiatric inpatients on several anxiety and depression measures, as mediated by private self-consciousness. The overall concordance between clinicians' and patients' ratings is quite high, particularly on the depression measures. Levels of private self-consciousness do not appear to mediate concordance of structured behavior or symptom-based ratings of either anxiety or depression; however, there is limited support for levels of private self-consciousness mediating concordance between patients' global ratings of anxiety and clinicians' anxiety ratings.     

Alternative scoring system of repeated items on the MMPI: caveat emptor

There are 16 items in the standard MMPI group forms which are included twice. It was found that a number of computerized scoring services use only the first occurrence of repeated items in scoring the MMPI scales, whereas the handscoring templates use an arbitrary combination of the first and second occurrence of these items. Comparison of these conventions suggested a potential for significant differences in score, particularly on the Sc scale. Scoring a set of 126 MMPIs of chronic pain patients by both of these scoring conventions revealed differences of up to 10 T points on the Sc scale. It is recommended that a single scoring convention for the MMPI be adopted by psychologists. For several reasons we suggest that only the first occurrence of repeated items should be used for scoring purposes. In the absence of a single convention, comparisons between Sc scores on different protocols should not be made without first insuring that the protocols were scored in the same manner.     

Self-report measurement of type A behavior: toward refinement and improved prediction

Self-report measures of Type A personality receive wide research usage despite mounting evidence that they are poor predictors of coronary heart disease. It was proposed that the limited prediction results in part from the failure to restrict measurement to only those Type A characteristics that are demonstrably related to excessive stress. The first study in this article reports a factor analysis of all items on the Jenkins Activity Survey (JAS), the most popular Type A questionnaire, along with 25 stress symptoms. Self-ratings were obtained from both male and female college students. Only one stress-related factor emerged including 12 JAS items out of 44. These were relevant to (a) hard-driving and competitive, (b) time-urgent, and (c) hostile/irritated characteristics. Study 2 reports correlations of +.50 and +.43 between the stress-relevant JAS items and stress for new samples of female and male college students. Study 3 considers the broader personality correlates of scores on the stress-relevant Type A items and reports markedly different patterns for male and female college students. Predicted correlations were found on new samples between these personality correlates, considered as scales, and stress-relevant Type A scores and stress.     

Auditory word discriminations in the pigeon.

Four pigeons were trained on a multiple variable-interval 30-s extinction schedule with various pairs of spoken English words presented as the discriminative stimuli. The birds typically produced discrimination indices of 70% to 90% accuracy. Discrimination accuracy was improved by shortening the interval between auditory stimulus presentations, and by increasing the number of syllables in the words.