Heterogeneity in verbal memory: a marker of preclinical Alzheimer's disease?

Demonstrations of memory changes in those at risk for Alzheimer's disease by the presence of the APOE e4 allele have been inconsistent to date. The present study went beyond traditional analyses of central tendency (i.e., group differences on mean test scores) and also conducted distribution analyses to search for subtle cognitive differences in subgroups of normal-functioning elderly persons with the APOE e4 genotype. The results of the study revealed that (a) the e4 and non-e4 groups failed to differ in terms of their mean scores on tests of memory and verbal skills; and (b) relative to the non-e4 group, the e4 subjects had significantly greater heterogeneity of variance on the memory measures but not on fundamental verbal skills. Logistic regression analyses indicated that the discrepancy in scores on the memory measures was a significant predictor of genotype group membership (82% correct classification rate). Implications of these findings for the detection of a preclinical phase of AD are discussed.     

Connectivity among semantic associates: an fMRI study of semantic priming

Semantic priming refers to a reduction in the reaction time to identify or make a judgment about a stimulus that has been immediately preceded by a semantically related word or picture and is thought to result from a partial overlap in the semantic associates of the two words. A semantic priming lexical decision task using spoken words was presented in event-related fMRI and behavioral paradigms. Word pairs varied in terms of semantic relatedness and the connectivity between associates. Thirteen right-handed subjects underwent fMRI imaging and 10 additional subjects were tested in a behavioral version of the semantic priming task. It was hypothesized priming would be greatest, reaction time fastest, and cortical activation reduced the most for related word pairs of high connectivity, followed by related word pairs of low connectivity, and then by unrelated word pairs. Behavioral and fMRI results confirmed these predictions. fMRI activity located primarily in bilateral posterior superior and middle temporal regions showed modulation by connectivity and relatedness. The results suggest that these regions are involved in semantic processing.     

The Inventory of Children's Individual Differences: Development and Validation of a Short Version

The development of programmed, actuarial interpretation of personality tests, especially the MMPI, is discussed. The presentation seeks to present a synoptic overview of the topic, including its more important trends, apparent present status, and possible consequences. Several commercially available systems are described, and an example of the output of each of three of them, in interpreting the same MMPI protocol, is presented for comparative illustration.     

the impacts of self-control and social bonds on juvenile delinquency in a national sample of midadolescents

This study examines the effects of self-control and social bonds on delinquent behavior in a nationally representative sample. It is proposed that both self-control and social bonds affect delinquency and that the effects of these factors interact with each other. These hypotheses were tested in a regression model controlling for race, gender, delinquent association, and illegitimate opportunity. As predicted, low self-control is positively related to juvenile delinquency while social bonds are negatively related to delinquency. Some of the interaction terms between self-control and social bonds significantly impact delinquency, suggesting that the effects of self-control and social control are interdependent.     

Information underpinning anticipation of goal-directed throwing

We identified the information used to anticipate throw direction in handball. In two experiments, we examined how anticipation performance is affected when the information from one of five body areas (right arm, shoulders, hips, trunk, or total throw side) was either neutralized or decoupled from the motion of other body segments. In the first experiment, performance was significantly reduced when information from the throwing arm was neutralized, irrespective of skill levels. Skilled participants were negatively affected when the shoulders, hips, and trunk were neutralized, whereas less-skilled participants showed trends toward improvement under identical conditions. In the second experiment, partially disrupting relative motion via decoupling was not enough to reduce the anticipation performance among skilled participants to chance levels, whereas less-skilled participants lost their ability to anticipate in three conditions. Our findings suggest that skilled and less-skilled participants employ different information extraction strategies, yet information from the throwing arm is critical to anticipation for both groups. The two experiments suggest that relative motion mediated by both the absolute displacement trajectories of individual marker locations and their relative timings are important in informing anticipation, irrespective of skill level.     

Facilitating the Academic Success of International Students

International seminarians seeking an education at academic institutions located in the United States often face a host of learning challenges. Seminary faculty that teach in these institutions are often confronted with a need to adjust their teaching methods to facilitate learning by international students. This essay outlines specific strategies to facilitate academic success of international seminarians by offering specific teaching methods for faculty and learning strategies for international students. Topics include training faculty in how to respond to diverse learning styles, expanding learning environments beyond the classroom, methods for enhancing student participation, and development of assignments. Strategies for student success include developing skills in how to improve note taking, critical reading, and writing.     

Visual search under conditions of very rapid sequential Input rates

The purposes of the present experiment were to provide information on rate of information processing in visual perception and to determine the degree to which the “sequential blanking” effect found by Mayzner. Tresselt, and Cohen (1966) constituted a limitation on rapid sequential input rates. A 10-channel tachisto scope was employed that permitted controlled durations of each of the 10 channels and the 9 inter channel intervals. The S’s task was one of visual search or detection in which he searched for a target letter among noise letters. A temporal interval forced-choice procedure was used. In addition to varying the rate at which letters were sequentially presented, various irregular temporal spatial orders of presentation of the letter sequences were employed and the direction and orientation of the display in the visual field was varied as was also the spacing between adjacent stimuli. No evidence of “sequential blanking” was found either in terms of the detection criterion or in the Ss’ phenomenal reports. Detection performance was as good at a rate of 2 1/2 msec per letter as it was at a rate of 30 msec per letter.