No abstract

Recently Muenzinger (5) and Wischner (11) have discussed certain differences in the results of their respective experiments on the effect of shock upon the learning of a discrimination habit by the white rat. The present writers do not question the results obtained by either investigator, but call attention to one noteworthy feature: In the studies of both, shock was employed for right choices only, or for wrong choices only. In view of Muenzinger's suggestion (4) that shock anywhere after choice facilitates learning, and in view of the literature concerning secondary reinforcement in discrimination learning situations, it seems desirable to discover whether shock will facilitate such learning when the shock cannot serve as a cue to the correctness or incorrectness of the responses, i.e., when shock accompanies both right and wrong responses in the same subjects. If the shocked group learns faster than the nonshocked group, Muenzinger's suggestion is upheld, and the results are consistent with the literature on secondary reinforcement. METHOD SubjectsThe subjects were 20 experimentally naive albino rats from the colony maintained by the Psychology Department at Bowling Green State University. There were 10 males and 10 females, ranging in age from 60 to 100 days at the start of the experiment. With the aid of a table of random numbers, 5 males and 5 females were assigned to each condition.

Equidistance settings were obtained from 50 Os with a Howard-Dolman type apparatus which was either stationary or rotating about O at angular speeds of 60 to 180 deg/sec. The correlation between the settings decreased as the disparity of the speeds being compared increased, and there was a sharp drop in correlation between the stationary condition and any speed. At any speed of rotation, there was an increase in the variability of the settings as viewing time decreased and a sharp increase below .3 sec. A positive localization error was made by 24 Os and a negative error was made by 26 Os. There appears to be a relationship between positive errors and exophoria and between negative errors and esophoria.

No abstract

Forty college students served as 5s. Six-consonant slides were tachistoscopically rear-projected on a screen with a central fixation point. Four orders of report were used: unspecified, counterbalanced, left to right, and right to left. The order of report was indicated prior to stimulation in some groups and after stimulation in others. Practice in scanning was given some groups. Thus the effects of order of report, training, and expectancy on differential perception in the visual field could be assessed. The order of report and expectancy affected 5"s performance, but training did not, giving support to the cognitive scanning hypothesis rather than to the selective retinal training hypothesis.