Visual orientation estimation

A systematic error is reported in orientation estimation, in that on average, estimates are closer to the vertical axis than are the stimuli by up to 6°. This systematic error results from a specific mechanism that may be related to depth perception, and that is avoided in certain circumstances or when other mechanisms take over. For example, the estimates of one observer who was a welltrained professional draughtsman did not show this systematic error. Furthermore, for all observers tested, estimation of clock time is not subject to the regular orientation estimation error. Rather, observers tend to estimate timesas slightly further from the quarter hour than they really are. Orientation judgment channel capacity was also studied under various conditions. The number of discriminable orientations is far above the magic number “7“ limit, reaching over 20 in optimal circumstances. The distribution of discriminable orientations is nonlinear, in that these are more closely packed about the horizontal and vertical axis than at the oblique.     

Mood-congruent memory in depression: emotional priming or elaboration?

We investigated whether mood-congruent memory (MCM) bias in depression is a function of implicit or explicit memory. Implicit memory is taken as a measure of ease of activation, whereas explicit memory also taps elaboration. As expected, MCM bias was found in the explicit memory task but not in the implicit memory task. We believe this finding supports the involvement of elaborative mechanisms in MCM. In addition, memory bias was found with words related to depression but not with words denoting physical threat. Thus, the MCM bias in explicit memory was found to be specific to information that was congruent with depression rather than to all negative information.     

Selection of vigilant and avoidant coping strategies among repressors, highly anxious and truly low anxious subjects

70 female graduate students from a western university were classified as to personality type: Highly Anxious, Truly Low Anxious, and Repressing, using a combination of scores from the Taylor Manifest Anxiety Scale and the Marlowe-Crowne Social Desirability Scales. Each subject's preference for monitor or blunter coping strategy was assessed via the Miller Behavioral Style Scale. Highly Anxious subjects chose significantly more monitor strategies than did Truly Low Anxious subjects or Repressors. The number of blunter strategies chosen did not differ across personality types. Chi-squared indicated that Highly Anxious subjects were more often classified as monitors than blunters whereas the proportions of monitors and blunters did not significantly differ between Truly Low Anxious subjects and Repressors. Results suggest that the repressor trait is distinct from avoidant and vigilant coping strategies.     

The effect of instruction with relational and item-specific elaborative strategies on young children's organization and free recall

One hundred and sixty second-grade children were assigned on the basis of a free recall pretest to four instruction conditions and were given a series of lists of pictures for free recall. For three groups, the instructions were directed at encoding either (a) list organizational information, (b) item-specific semantic information, or (c) organizational and individual item information, while the fourth group constituted a “No-training” control with standard free recall instructions. The subjects received either related or unrelated lists during the training phase and related or unrelated lists during two post-tests, immediately following and 1 week after training. For both types of lists, instructions emphasizing list organization were more effective than those emphasizing item-specific elaboration. Subjects given individual item elaborative instructions showed levels of recall which were comparable to those of the control subjects. While the combined effect of organizational and individual item processing did not exceed the performance produced by organizational instructions alone, the degree of generalization was greater for subjects processing both kinds of information, especially when subjects received related lists during training.     

Hemisphere functioning and motor imitation in autistic persons

Previous research has found that a high proportion of autistic individuals exhibit an atypical pattern of hemispheric specialization suggestive of impaired left hemisphere functioning: namely, right hemisphere dominance for both verbal and visual-spatial processing. Studies of brain-damaged persons have suggested that the left hemisphere is specialized for the use of nonverbal gesture. Since a major characteristic of autism is an impairment in the use of gesture, it was predicted that autistic persons would also show atypical hemispheric specialization for motor imitation. To test this hypothesis, hemispheric activation was measured using EEG recordings of alpha rhythm in autistic and matched normal control subjects during four motor imitation tasks. Autistic subjects showed significantly greater right hemisphere activation during the imitation tasks, than normal subjects. This pattern was particularly evident in younger autistic subjects and during oral, rather than manual, imitation tasks.     

A simplification of a completeness proof of Guaspari and Solovay

The modal completeness proofs of Guaspari and Solovay (1979) for their systems R and R ^– are improved and the relationship between R and R ^– is clarified.