Individual response patterns in binary choice tasks with nondiscriminable stimuli

The present experiment sought to determine whether individual Ss tend to employ repeatedly the same response patterns in binary choice tasks containing nondiscriminable stimuli and, if so, whether the response sequences when used to constructstimulus sequences improve the performance of other choice tasks. Information and frequency analyses of the response sequences of 48 Ss showed moderate consistency of patterning within a light and within a tone task. Performance of a card task following the light and tone tasks was closely related to the task (light or tone) from which the stimulus sequence was obtained. The frequency analysis showed that repetition patterns were preferred by most Ss but at the expense of alternation responses. The presentation of reinforcement in the card task did not improve performance over that observed in the light and tone tasks.     

The role of stimulation in the delay of onset of crying in the newborn infant

Crying is said to result from stimulus need. An experiment was done in which infants were stimulated during quiet periods to see if this would postpone the onset of crying. The results were positive. An alternative explanation in terms of internal temperature control is considered.     

Negative recency and event-dependence

In a two-choice situation with event-probabilities of 0.67 and 0.33, recency effects were studied as a function of (a) event-dependence and (b) fore-knowledge of event-probabilities. The following conclusions are drawn: (1) Belief in some kind of event-dependence is a necessary condition for the occurrence of negative recency; (2) Foreknowledge of the event-probabilities does not affect recency phenomena; (3) The behaviour of subjects in the two-choice situation, is less irrational than some writers have claimed.     

Sex differences in the duration of visual attention

Normal adult males and females looked at a series of photographs containing either a single adult male or female. Ss viewed each picture for as long as they wished. Assuming that measures of the duration of attention would reflect Ss attraction for the opposite sex, it was hypothesized that Ss would spend relatively more time viewing photographs of the opposite sex. The results failed to support the hypothesis. Although males did not differentially attend to the stimuli, females looked significantly longer at the females than they did at the males. The results were interpreted in terms of the “overt sexual content” of the stimuli and socially conditioned attentiveness and inattentiveness.     

Specificity of a cutaneous receptor

Absolute vibrotactile thresholds are determined on the human tongue and compared to corresponding data obtained on the hand. The mucosa of the tongue is devoid of Pacinian corpuscles but the hand is richly with these nerve endings. Summation of energy is characteristic of responses recorded from tissue containing Pacinian corpuscles and absent where the corpuscle is specifically sensitive to mechanical vibration.