Variability of response location for pigeons responding under continuous reinforcement, intermittent reinforcement, and extinction

The effect of several reinforcement schedules on the variability in topography of a pigeon's key-peck response was determined. The measure of topography was the location of a key peck within a 10-in. wide by 0.75-in. high response key. Food reinforcement was presented from a magazine located below the center of the response key. Variability in response locus decreased to a low value during training in which each response produced reinforcement. Variability increased when fixed intervals, variable intervals, random intervals, or extinction were scheduled.     

SEX AND JOB ORIENTATION

Three samples, each divided into males and females, were asked to indicate to what degree some job characteristics were important to them. The job characteristics represented both intrinsic and extrinsic factors. In the first sample (40 male and 44 female university students) there was no sex difference in job orientation. Both selected the intrinsic factors more than the extrinsic factors. There was also no sex difference in the second sample, which consisted of 68 male and 33 female public school teachers. They, however, stressed as many intrinsic factors as extrinsic. The general results of the third sample showed significant sex differences. The sample of 259 male and 143 female employees represented a technical division of a large service-oriented organization. Education and job level were significantly different for the two subgroups. When these two variables were controlled for a sample of clerks and of first-level supervisors, no sex difference appeared in job orientation. The results also showed that the higher the job level, the more intrinsically-oriented the employees were regardless of their sex.     

Tactile short-term memory

Subjects tried to recall the location of a tactile stimulus on the underside of the forearm after delays of 0, 3, 5, 10, 15, 30, 45 and 60 sec. When “rehearsal” was prevented by requiring subjects to count backwards during the delay, accuracy of recall decreased systematically reaching an asymptote after 45 sec. When subjects were left free to “rehearse,” this did not affect the decline in accuracy over the first 10 sec. Between 10 and 15 sec. there was a significant increase in accuracy followed by a slow decline which had not reached asymptote by 60 sec. It is suggested that tactile STM (short-term memory) depends on two processes, a fading sensory trace which is unaffected by distraction and a less labile system which does not appear to be verbal but which depends on “rehearsal.”     

Prior stimulation and the perception of causality

An attempt was made to discover whether, in conditions similar to those of Michotte, the number of causal responses given by subjects was influenced by stimulation during the period just before the main experiment. Time-intervals between the arrival of object A and the departure of object B were systematically varied within the range 60 to 390 msec. Those who had earlier been exposed to shorter time-intervals (60 to 210 msec.) gave fewer causal responses than those who had been exposed to longer ones (150 to 300 msec. and 240 to 390 msec.). A possible explanation is offered in terms of the modification of existing “schemata.”     

A technique for the construction of discrete dichotic stimulation material

Procedures are described for the generation, synchronization. and accurate spacing of discrete dichotic stimulation material. A suggested standard definition of interpair interval is proposed.