Observing Behavior Topography in Delayed Matching to Multiple Samples

The Psychological Record - This study examined relations between eye movements and accuracy scores in a delayed matching-to-sample procedure with multiple sample stimuli. Four adult humans...     

What is the role of mothers in the acquisition of termite-fishing behaviors in wild chimpanzees (Pan troglodytes schweinfurthii)?

This paper explores the role of maternal influences on the acquisition of a tool-using task in wild chimpanzees (Pan troglodytes schweinfurthii) in order to build on and complement previous work done in captivity. Young chimpanzees show a long period of offspring dependency on mothers and it is during this period that offspring learn several important skills, especially how to and on what to forage. At Gombe National Park, one skill that is acquired during dependency is termite-fishing, a complex behavior that involves inserting a tool made from the surrounding vegetation into a termite mound and extracting the termites that attack and cling to the tool. All chimpanzees observed at Gombe have acquired the termite-fishing skill by the age of 5.5 years. Since the mother is the primary source of information throughout this time period, I investigated the influence of mothers' individual termite-fishing characteristics on their offsprings' speed of acquisition and proficiency at the skill once acquired. Mother's time spent alone or with maternal family members, which is highly correlated to time spent termite-fishing, was positively correlated to offspring's acquisition of critical elements of the skill. I also investigated the specific types of social interactions that occur between mothers and offspring at the termite mound and found that mothers are highly tolerant to offspring, even when the behavior of the offspring may disrupt the termite-fishing attempt. However, no active facilitation by mothers of offsprings' attempts were observed. Electronic Supplementary Material Electronic supplementary material Supplementary material is available for this article at http://dx.doi.org/10.1007/s10071-005-0002-7 and accessible for authorised users.     

“To Cook, Sew, to Be a Man”: The Socialization for Competence and Black Men's Involvement in Housework

The context in which Black children do housework and its effect on adult behavior have been relatively unexplored. This article presents analyses of the recollections of 45 Black fathers of young children about performing household chores when they were children and its relevance for their involvement in housework as adults. The fathers' relatively high involvement in housework is traced to the ‘socialization for competence’ that most of them experienced as boys. Four dimensions in the socialization for competence are discussed: the actual household chores done in childhood, the ways of performing them, the rationale for assigning them, and parents' justifications for making children engage in housework. Although the childhood socialization for competence does not translate uniformly into men's sharing housework equally, it takes away ineptitude as an excuse for resisting housework as adults.     

On the problems of being more or less the same

Sixty children aged 2–3 to 5-2 were given four quantity tasks which tested their understanding of more and same. Two tasks involved addition, two involved judgment of static quantities. One of each type of task required a manipulative response, and one of each required a yes/no judgment. The tasks involved judgments of equality and inequality. Tasks involving a manipulative response were significantly easier than those involving a yes/no judgment, indicating that the nature of the response required of the child is crucial. All other differences were negligible, indicating that the other task variables investigated do not affect the child's ability to respond correctly. The ability to make accurate responses was not strongly associated with counting ability. There was a significant difference in the children's counting responses depending on the method used to elicit it.     

Perception of American sign language in dynamic point-light displays

Perception of dynamic events of American Sign Language (ASL) was studied by isolating information about motion in the language from information about form. Four experiments utilized Johansson's technique for presenting biological motion as moving points of light. In the first, deaf signers were highly accurate in matching movements of lexical signs presented in point-light displays to those normally presented. Both discrimination accuracy and the pattern of errors were similar in this matching task to that obtained in a control condition in which the same signs were always represented normally. The second experiment showed that these results held for discrimination of morphological operations presented in point-light displays as well. In the third experiment, signers were able to accurately identify signs of a constant handshape and morphological operations acting on signs presented in point-light displays. Finally, in Experiment 4, we evaluated what aspects of the motion patterns carried most of the information for sign identifiability. We presented signs in point-light displays with certain lights removed and found that the movement of the fingertips, but not of any other pair of points, is necessary for sign identification and that, in general, the more distal the joint, the more information its movement carries.     

Self-monitoring personality at work: a meta-analytic investigation of construct validity

The validity of self-monitoring personality in organizational settings was examined. Meta-analyses were conducted (136 samples; total N = 23,191) investigating the relationship between self-monitoring personality and work-related variables, as well as the reliability of various self-monitoring measures. Results suggest that self-monitoring has relevance for understanding many organizational concerns, including job performance and leadership emergence. Sample-weighted mean differences favoring male respondents were also noted, suggesting that the sex-related effects for self-monitoring may partially explain noted disparities between men and women at higher organizational levels (i.e., the glass ceiling). Theory building and additional research are needed to better understand the construct-related inferences about self-monitoring personality, especially in terms of the performance, leadership, and attitudes of those at top organizational levels.     

Probing the Time Course of Nonlinear Discriminations during Human Electrodermal Conditioning

Animal-based theories of Pavlovian conditioning propose that patterning discriminations are solved using unique cues or immediate configuring. Recent studies with humans, however, provided evidence that in positive and negative patterning two different rules are utilized. The present experiment was designed to provide further support for this proposal by tracking the time course of the allocation of cognitive resources. One group was trained in a positive patterning schedule (A−, B−, AB+) and a second in a negative patterning schedule (A+, B+, AB−). Electrodermal responses and secondary task probe reaction time were measured. In negative patterning, reaction times were slower during reinforced stimuli than during nonreinforced stimuli at both probe positions while there were no differences in positive patterning. These results support the assumption that negative patterning is solved using a rule that is more complex and requires more resources than does the rule employed to solve positive patterning.     

全球生命伦理学——梦想还是梦魇？

导言对于出席这次在东京召开的第四届国际生命伦理学大会开幕式的很多人来讲,好像有实现了一个梦想的感觉。国际生命伦理学学会和亚洲生命伦理学学会的共同努力是一个强有力的信号：     

Change in cognitive functioning associated with apoE genotype in a community sample of older adults

The influence of a genetic risk factor, apolipoprotein E (apoE) epsilon4 variant, was assessed in older adults aged 70 to 94 on 3 occasions over 7 years. The results of latent growth curve analyses are reported for individuals genotyped for apoE at the 2nd measurement occasion (n = 601) and for a subsample of individuals without probable or definite dementia during the 1st or 2nd occasion (n = 434). ApoE-epsilon4 status was a significant predictor of level and change in memory performance and change in speed performance in the full sample, and of initial level and change in memory performance in the nondemented subsample. These results support previous findings that apoE-epsilon4 is associated with accelerated memory deterioration in individuals without clinical dementia.     

The structure of language abilities at 4 years: a twin study

Normal language development was studied in 310 pairs of 4-year-old twins born in the United Kingdom in 1994. Twins were assessed individually in their homes on a diverse battery of language and nonverbal measures. Rotated factor analyses indicated the presence of a general Language factor (L) as well as a general Nonverbal (NV) factor. Moderate genetic influence was found for both L and NV abilities. Bivariate genetic analysis estimated a genetic correlation of .63 between L and NV abilities, implying that over half of the genetic influence on L overlaps with genetic influence on NV. These results suggest that at age 4, genetic influences on individual differences in language overlap substantially with genetic influences on individual differences in other cognitive abilities, although perhaps less so than later in development.