Development of differences in response latencies to right and left visual fields

Robust lateralization developed in right-handed adults who were asked to judge letter pairs as "same" or "different" during 4608 trials. By the end of the first two blocks (768 trials) "same" responses were favored when presented in the RVF (transmitted directly to the left hemisphere) and "different" responses were favored when presented in the LVF (transmitted direction to the right hemisphere). This gradually reversed over sessions with "same" responses becoming faster for letters presented in the LVF, and "different" responses becoming faster for stimuli presented in the RVF. The laterality acquired under these conditions was cumulative and reproducible, appeared in all 16 subjects, and was preserved between sessions a week apart. The data suggest that laterality is a flexible and reversible characteristic of the human brain even when stimulus and task remain constant.     

Representation of linear orders

Two binary classification tasks were used to explore the associative structure of linear orders. In Experiment 1, college students classified English letters as targets or nontargets, the targets being consecutive letters of the alphabet. The time to reject nontargets was a decreasing function of the distance from the target set, suggesting response interference mediated by automatic associations from the target to the nontarget letters. The way in which this interference effect depended on the placement of the boundaries between the target and nontarget sets revealed the relative strengths of individual interletter associations. In Experiment 2, students were assigned novel linear orders composed of letterlike symbols and asked to classify pairs of symbols as being adjacent or nonadjacent in the assigned sequence. Reaction time was found to be a joint function of the distance between any pair of symbols and the relative positions of those symbols within the sequence. The effects of both distance and position decreased systematically over 6 days of practice with a particular order, beginning at a level typical of unfamiliar orders and converging on a level characteristic of familiar orders such as letters and digits. These results provide an empirical unification of two previously disparate sets of findings in the literature on linear orders, those concerning familiar and unfamiliar orders, and the systematic transition between the two patterns of results suggests the gradual integration of a new associative structure.     

Children's understanding of conversational principles

Sixteen preschool, first-, and third-grade children were presented with short stories ending with a verbal statement by a story character. Two alternative ending statements were provided. One alternative violated a postulate (H. P. Grice, 1975, in P. Cole & J. Morgan (Eds.), Syntax and Semantics (Vol. 3), New York: Academic Press) or a reasonable request condition (D. Gordon & G. Lakoff, 1971, Conversational postulates, papers from the seventh regional meeting of the Chicago Linguistic Society, University of Chicago, Department of Linguistics), while the other alternative did not. The child's task was to choose the “funny or silly“ ending, i.e., the violation. Data analysis showed that 100% of the third-graders, 83% of the first-graders, and 19% of the preschoolers performed with significant (P < .02) accuracy. These results suggest that children's understanding of conversational principles improves considerably between preschool and first grade. There were no significant differences among four types of conversational principles examined.     

Cognitive dysfunction in compulsive checkers: Further explorations

Recent evidence suggests a relationship between certain memory deficits and compulsive-checking behavior. The present study explores this relationship in the context of several additional memory capacities not yet investigated. Using the Maudsley Obsessional-Compulsive Inventory and the Everyday Checking Behavior Scale four groups of Ss were identified: (1) frequent checkers, (2) occasional checkers, (3) infrequent checkers and (4) noncheckers. Consistent with previous research, a memory-for-actions task indicated a deficit among compulsive checkers. Furthermore, checking status was found to be negatively related to memory functioning as measured by the Wechsler Memory Scale (WMS) and the Cognitive Failures Questionnaire (CFQ). This memory deficit was most pronounced on the Logical Memory subtest of the WMS. Checkers appear to have difficulty recalling details of meaningfully linked sequences, either presented in narrative form or engaged in personally. Although the reasons for these checking-related deficits are not clear, a complete understanding of checking phenomena will involve an appreciation of the role played by memory deficits.     

THE IMPACT OF PSYCHOLOGICAL TESTING ON EDUCATIONAL AND PERSONNEL SELECTION IN AFRICA

Psychological testing for Education and Personnel selection is of great importance in the efforts by many African countries to ensure that suitable candidates are selected for education beyond the primary school level and for training for different employment. Major investigations directed to this need have been in the area of adapting tests already available in Western countries and determining the reliability and predictive validity of battery of tests so adapted and their tryout in African schools to determine their efficiency as tools for selection.     

Neurology,psychology, and extraordinary religious experiences

Temporal lobe epilepsy and certain personality disorders often result in experiences described as religious. TLE research suggests a possible neurological basis for such experiences. Immediately the question arises about the authenticity of these experiences as religious. An experience is authentic if it furthers the authentic growth of the subject, regardless of what triggered it. So pathology may occasion authentic religious experiences, even as history exemplifies. For practical purposes, the further question about God in religious experience is secondary. The exception, miraculous occurrences, should not be granted without sufficient reason. This approach dissolves all conflict between science and faith.     

Reactivity and unreliability of husbands as participant observers

This study examined the reliability and reactivity of participant observation. Twelve couples engaged in two discussions in a laboratory, one on a conflict topic and one on a consensus topic. For the eight couples in the experimental sequences, a baseline discussion was followed by participant observation in which the husband recorded his wife's use of I while continuing to converse. The four couples in the control sequences conversed without participant observation. Compared to observations made by a trained observer, the husbands were unreliable observers, underestimating their wives' use of I. Participant observation was reactive (P<.01), with more wives decreasing their use of I in the experimental sequences than in the control sequences (p<.094). The topic of discussion did not differentially influence reliability or reactivity.This research was conducted as the first author's independent doctoral research project. We extend gratitude to the Research Council of the University of North Carolina at Greensboro for Grant 0-2-110-218-XXXXX-7548; the Statistical Consulting Center of the University of North Carolina at Greensboro; two anonymous reviewers; and our research assistants, Suzanne Brannon, Ben Hardie, Kathy Lindamood, Amy Mitchem, Regina Pierce, and Elga Wulfert. Portions of this paper were presented at the meeting of the Association for Advancement of Behavior Therapy, Washington, D.C., December 1983.     

Behavioral consequences of song learning: Discrimination of song types by male white-crowned sparrows

The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.