Timing behavior and conditioned fear

Rats were trained on a two-response timing procedure which required that response B follow response A by at least a minimum specified interval in order to be reinforced with food. Repeated presentation (5 min on, 5 min off) of an auditory warning stimulus terminated by a brief electric shock to the feet (conditioned fear) produced a marked suppression in the frequency of A-to-B response sequences during the warning stimulus. The distribution of A-to-B interresponse times (timing behavior), however, did not change during the warning stimulus.     

Nine Critical Questions About Selective College Admissions

The misgivings of college faculty, college administrators, and high school counselors about selective admissions are focused on 9 issues. Data relevant to those issues reveal that: (1) prediction of grades is sufficiently accurate to be useful; (2) prediction equations from one year are sound for use in the immediately succeeding years; (3) predictions of first-year grades are related to performance over the 2-year period at a junior college and the 4-year career at a senior college; (4) there may need to be separate prediction procedures for widely different majors, such as science and nonscience; (5) accurate predictions can be made before the student has completed high school; (6) the nonacademic courses students take do not reduce prediction accuracy; (7) introduction of selectivity has not been found to decrease diversity in educational opportunity; (8) grading practices in an institution will tend to fluctuate with the degree of selectivity; and (9) procedures are available to set admissions cutoffs, to provide students with sound counseling information, and to provide a second chance for those who do net meet minimum admissions standards.     

Job Satisfaction Factors Among Underprivileged Workers

16 factors dealing with motivation on the job were presented in a paired comparison format to 513 underprivileged adults in a federally supported job retraining project in South Carolina. They were directed to select for each pair the one factor which was more important to them on a job. Analyses were computed for the total sample and for subsamples based on race, sex, and economic environment of residence. The results point out that intrinsic, personal factors are more important than job context factors. Slight differences were found across sex; larger differences were found across race and economic environment.     

Brightness inhibition re size of surround

The amount by which the apparent brightness of a visual field is inhibited by a surrounding field depends on the area of the inhibiting field. Interocular brightness matches showed that, as the size of a surrounding annulus is increased from a thin ring, the degree of inhibition on the brightness of an inner disk increases rapidly at first and then more slowly as the effect approaches an asymptote. The increase of the inhibition with size of annulus can be expressed as an increase in the exponent of the power function that relates the apparent brightness of the dish to its physical luminance.     

New analysis of variance formulas for treating data from mutually paired subjects

The experimental design considered in this paper is one in which each of a group of several subjects is observed in the presence of each of the other subjects of the group, the entire set of possible pairings being repeated or replicated on several occasions. Analysis of variance formulas are described for this somewhat unusual design. Both the model of constants and mixed model are considered. Reliability formulas growing out of the analysis of variance calculations are developed.This work was supported in part by grants M-627; M-627C from the National Institutes of Health, Public Health Service.     

The effects of a pre-time-out stimulus on matching-to-sample of humans,

In each of two experiments human subjects were intermittently reinforced with money on a fixed-ratio schedule for emitting correct matching responses. A pre-time-out stimulus which signaled removal of positive reinforcement was periodically superimposed. In the first experiment the superimposed pre-time-out stimulus was paired with a 1-min or 4-min response-independent time out. In the second experiment the pre-time-out stimulus was paired with a 1-min or 4-min time out contingent on the incorrect responses. The pre-time-out stimulus did not markedly influence performance when the time out was response independent. In contrast, the pre-time-out stimulus markedly suppressed incorrect responding when the time out was contingent on the incorrect responses. When duration of this time-out was increased from 1-min to 4-min, suppression of incorrect responding increased and correct responding was suppressed. Therefore, behavioral suppression by a pre-time-out stimulus was obtained only when the signaled aversive event-time out-was response produced. In this case, suppression was influenced by time-out duration.     

Effect of Person

The role of the experimenter in the behavioral study, although recognized by Darwin, Pavlov, psychiatrists and others, has not been adequately evaluated in terms of the quantitative measures of the CR. Our study in this paper concerns especially the cardiac changes induced by “Person” in normal and pathological animals—monkey, dog, cat, opossum, guinea pig and rabbit. Owing to the greater sensitivity of the cardiovascular and respiratory systems, these are more reliable and delicate measures than the usual somatic muscular ones. The Person can be used as an unconditional stimulus on the basis of which conditional reflexes are formed. Person has an especially pronounced effect on neurotic animals—shown often in a more pronounced way in the cardiorespiratory responses than in the more superficial behavioral ones. This Effect of Person may provide insights into the production of neurosis as well as some of the beneficial effects of therapy, e.g., the personal factor of the therapist.     

The interaction between sensory and tonic factors in the perception of the vertical in pigeons

In two separate experiments, 21 pigeons were given 10 days of training to peck a key on which a white vertical line was exposed. Next, the birds were given generalization tests along the angularity dimension with the floor tilted 24° to the right or to the left. Reliable asymmetrical gradients were obtained with enhanced responding to the side toward which the floor was tilted. This posturally induced distortion in the visual perception of the vertical indicates that sensory-tonic interactions typically observed in humans have a parallel in this lower species.