Visuo-Proprioceptive Matching Errors Are Consistent with Biases in Distance Judgments

People make systematic errors when matching the location of an unseen index finger with that of a visual target. These errors are consistent over time, but idiosyncratic and surprisingly task-specific. The errors that are made when moving the unseen index finger to a visual target are not consistent with the errors when moving a visual target to the unseen index finger. To test whether such inconsistencies arise because a large part of the matching errors originate during movement execution, we compared errors in moving the unseen finger to a target with biases in deciding which of two visual targets was closer to the index finger before the movement. We found that the judgment as to which is the closest target was consistent with the matching errors. This means that inconsistencies in visuo-proprioceptive matching errors are not caused by systematic errors in movement execution, but are likely to be related to biases in sensory transformations.     

Domain‐specific impulsivity in school‐age children

Impulsivity is a salient individual difference in children with well‐established predictive validity for life outcomes. The current investigation proposes that impulsive behaviors vary systematically by domain. In a series of studies with ethnically and socioeconomically diverse samples of middle school students, we find that schoolwork‐related and interpersonal‐related impulsivity, as observed by teachers, parents, and the students themselves, are distinct, moderately correlated behavioral tendencies. Each demonstrates differentiated relationships with dimensions of childhood temperament, Big Five personality factors, and outcomes, such as report card grades. Implications for theoretical conceptions of impulsivity as well as for practical applications (e.g. domain‐specific interventions) are discussed.     

Probing the Brain Substrates of Cognitive Processes Responsible for Context Effects on Recognition Memory

ABSTRACT

Context effects on episodic recognition memory involve separable contributions of target-context binding, additive familiarity, and configural constancy. Here we examine whether these factors reflect contributions of processes attributed to different brain substrates. First, we challenged frontal and medial temporal lobe-based cognitive capacities in healthy young adults, employing divided attention tasks at encoding and retrieval, and extended retrieval delay, respectively. Target-context binding effects were specifically attenuated by delay, but not by divided attention. In a second experiment, older adults were identified by neuropsychological testing as having different levels of frontal and medial temporal lobe-dependent cognitive functions. Consistent with Experiment 1, older adults with low medial temporal lobe function exhibited reduced target-context binding effects, but levels of frontal function did not modulate binding effects. These findings indicate that unlike source memory, context effects on memory are associated with the integrity of medial temporal lobe-based processes but not with the integrity of frontal lobe-based processes. Our findings also emphasize the importance of discriminating between functional subgroups in the attempt to characterize memory processes in older adults.     

Genetic Mediation of the Associations Among Motor and Perceptual Speed and Adult Cognitive Abilities

Quantitative genetic analyses were conducted to determine the genetic mediation of the associations among motor speed, perceptual speed, and cognitive abilities in normal aging. Measures of motor performance, perceptual speed, and cognitive functioning in four domains (crystallized, fluid, spatial, and memory) were available from the Swedish Adoption/Twin Study of Aging. The sample included 206 twin pairs ranging in age from 44 to 82 years. A Motor Speed factor was constructed from 17 timed measures of motor performance. Heritability of Motor Speed was .26 in middle-aged twins and .00 in older twins. Results indicated that genetic variance in cognitive functioning in the middle-aged cohort may be defined by working memory, whereas genetic variance in the older cohort was defined by perceptual speed. Indications of a nonshared environmental component in the association among motor speed, perceptual speed, and spatial abilities suggest possible frontal lobe involvement.     

Social relationships,stressful life events,and self-reported physical health: Genetic and environmental influences

Abstract

This study investigates how the associations between self-reported health, stressful life events, and social relationships are mediated by genetic and environmental influences and how much of the variance in health is in common with variation in these psychosocial factors. The analyses are based on questionnaire data from 576 pairs of twins reared apart and twins reared together. The data revealed that for men environmental influences were solely important for variation in the psychosocial measures and were the primary mediators of the relationship with health. For women, on the other hand, a substantial portion of the variance in the psychosocial factors was due to genetic influences and these influences also contributed to the bulk of the correlations with health. The gender differences for the relationships and their mediation indicate that what should be regarded as a psychosocial factor of importance for health might differ between genders.     

Later life health optimism,pessimism and realism: Psychosocial contributors and health correlates

Prior research has established positive outcomes of health optimism (appraising one's health as good despite poor objective health (OH)) and negative outcomes of health pessimism (appraising health as poor despite good OH), yet little is known about their contributors. We examined the role of psychosocial factors (life event stress, depression, dispositional optimism, perceived social support) in health realism (appraising health in accordance with OH), optimism and pessimism among 489 older men and women. We then accounted for the psychosocial factors when examining multiple health correlates of health realism, optimism and pessimism. Controlling for age, gender and income, regression results indicate that depression and social support were associated with less health optimism, while dispositional optimism was associated with greater health optimism among those in poor OH. Dispositional optimism was associated with less health pessimism and life event stress was associated with greater pessimism among those in good OH. Beyond the effects of the psychosocial factors, structural equation model results indicate that health optimism was positively associated with healthy behaviours and perceived control over one's health; health pessimism was associated with poorer perceived health care management. Health optimism and pessimism have different psychosocial contributors and health correlates, validating the health congruence approach to later life well-being, health and survival.     

Rey AVLT: Developmental Norms for Children and the Sensitivity of Different Memory Measures to Age

Nine hundred and forty-three children (487 boys and 456 girls, age range 8 to 17 years, divided into 10 age cohorts) were administered the Hebrew version of the Rey AVLT. Separate norms for boys and girls in each age group are reported. Sensitivity to age for 14 memory measures extracted from the Rey AVLT was analyzed. One of the most consistent findings across the different scores is that memory changes in the 8- to 10- year-old age range are more dynamic than changes in the 11- to 17- year-old age range. The results also show a significant and consistent advantage for girls over boys on most of the verbal memory measures. Detailed analyses of sensitivity to age of the different measures extracted from the Rey AVLT provide very useful information for the diagnostician testing auditory-verbal memory in children.     

Genetic and environmental contributions to the associations between intraindividual variability in reaction time and cognitive function

Intraindividual variability (IIV) in reaction time has been related to cognitive decline, but questions remain about the nature of this relationship. Mean and range in movement and decision time for simple reaction time were available from 241 individuals aged 51–86 years at the fifth testing wave of the Swedish Adoption/Twin Study of Aging. Cognitive performance on four factors was also available: verbal, spatial, memory, and speed. Analyses indicated that range in reaction time could be used as an indicator of IIV. Heritability estimates were 35% for mean reaction and 20% for range in reaction. Multivariate analysis indicated that the genetic variance on the memory, speed, and spatial factors is shared with genetic variance for mean or range in reaction time. IIV shares significant genetic variance with fluid ability in late adulthood, over and above and genetic variance shared with mean reaction time.