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.     

Spatial stimulus cue information supplying auditory saltation

Auditory saltation is a misperception of the spatial location of repetitive, transient stimuli. It arises when clicks at one location are followed in perfect temporal cadence by identical clicks at a second location. This report describes two psychophysical experiments designed to examine the sensitivity of auditory saltation to different stimulus cues for auditory spatial perception. Experiment 1 was a dichotic study in which six different six-click train stimuli were used to generate the saltation effect. Clicks lateralised by using interaural time differences and clicks lateralised by using interaural level differences produced equivalent saltation effects, confirming an earlier finding. Switching the stimulus cue from an interaural time difference to an interaural level difference (or the reverse) in mid train was inconsequential to the saltation illusion. Experiment 2 was a free-field study in which subjects rated the illusory motion generated by clicks emitted from two sound sources symmetrically disposed around the interaural axis, ie on the same cone of confusion in the auditory hemifield opposite one ear. Stimuli in such positions produce spatial location judgments that are based more heavily on monaural spectral information than on binaural computations. The free-field stimuli produced robust saltation. The data from both experiments are consistent with the view that auditory saltation can emerge from spatial processing, irrespective of the stimulus cue information used to determine click laterality or location.     

Wanting,having, and satisfaction: examining the role of desire discrepancies in satisfaction with income

In 3 studies, the authors tested the predictors of income satisfaction, examining whether discrepanc between the things people have and the things they desire predict satisfaction. Study 1 manipulated the desirability of items that can be purchased with participants' income, and showed that their satisfaction with that income depended on the desirability of these items. Study 2 demonstrated that whether people's income enabled them to purchase the things they desired influenced their satisfaction with income. Study 3 found that the effect of comparisons with a person's past on income satisfaction is completely mediated by one's desires; and the effect of social comparison on income satisfaction is partially mediated by desires. Thus, desires play a pivotal role in determining people's satisfaction with income.     

Mechanisms of source confusion and discounting in short-term priming: 1. Effects of prime duration and prime recognition

Huber, Shriffrin, Lyle, and Ruys (2001) measured short-term repetition priming effects in perceptual identification with two-alternative forced-choice testing. There was a preference to choose repeated words following passive viewing of primes and a preference against choosing repeated words following active responding to primes. In this present study, we explored conditions of prime processing that produce this pattern of results. Experiment 1 revealed that increased prime duration under passive viewing instructions produces the active priming pattern. Experiment 2 assessed memory for primes: With poor recognition of primes, there was a strong preference for repeated words; however, with good recognition of primes, this preference was eliminated. These results are modeled by a computational theory of optimal decision making, responding optimally with unknown sources of evidence (ROUSE). In ROUSE, a preference for repeated words results from source confusion between primes and choice words. A reversal in the direction of preference arises from the discounting of words known to have also appeared as primes.     

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.     

Marital conflicts in the home when children are present versus absent

Characteristics of marital conflict when children (8-16 years) were present versus absent were compared on the basis of 47 mothers' and fathers' reports during a 15-day period. Mothers described 669 incidents of marital conflict, and fathers described 551 incidents. About two thirds of the conflicts occurred in children's absence. Contrary to predictions, conflicts in which children were present were more negative (e.g., more negative emotions, more destructive conflict tactics) and more often about children than were child-absent conflicts. Although parents may attempt to protect children from conflict exposure, children tend to be exposed to a relatively hostile and emotionally negative subset of the marital conflicts that occur in the home.     

Representing motion in a static image: constraints and parallels in art,science, and popular culture

Representing motion in a picture is a challenge to artists, scientists, and all other imagemakers. Moreover, it presents a problem that will not go away with electronic and digital media, because often the pedagogical purpose of the representation of motion is more important than the motion itself. All satisfactory solutions evoke motion-for example, dynamic balance (or broken symmetry), stroboscopic sequences, affine shear (or forward lean), and photographic blur-but they also typically sacrifice the accuracy of the motion represented, a solution often unsuitable for science. Vector representations superimposed on static images allow for accuracy, but are not applicable to all situations. Workable solutions are almost certainly case specific and subject to continual evolution through exploration by imagemakers.     

Second-class citizen? Contract workers' perceived status,dual commitment and intent to quit

Outsourcing of jobs to contract workers who work alongside a client's employees has changed the human resource landscape of many organizations. In this study we examine how a contract worker's perceived employment status similarity to the client's own standard employees influences his/her affective commitment to both the client and the employer and ultimately intent to quit the employer. Using a sample of 623 contract workers, we found strong support for our hypotheses. In particular, findings indicate an important role for perceived employment status at the client organization in driving contract worker's attitudes and that contract workers consider both the client and the employer when making decisions to leave the employer. Implications for managing contractor relationships are discussed.     

Responsibility: The tie that binds

People share significantly more money with others in common lab paradigms like the dictator game than they do in real life. What accounts for this difference? Paradigms like the dictator game link each recipient to a single dictator with the implication that each recipient can receive funds from only one person. We argue that this “burden” of responsibility to a single recipient helps to explain high levels of laboratory sharing. In two experiments—a modified dictator game experiment and a charitable giving experiment—participants donated significantly more to others when they were solely responsible for a recipient's outcome than when the responsibility for a recipient was potentially shared. Taken together with past findings from social psychology and experimental economics, the results show how unambiguous responsibility for a single recipient increases generosity.