Perceptual identification across the life span: a dissociation of early gains and late losses

The age-correlated gains and losses in visual identification under backward pattern masking were studied in a representative sample of 226 individuals ranging from 6 to 88 years of age. Participants identified masked symbols at leisure under high and low stimulus quality and at varying Stimulus Onset Asynchronies. Performance increased from childhood to early adulthood and then decreased, describing the common inverted U-shaped function. However, measures of general processing speed accounted for the gains in childhood and adolescence but not for losses in older age. This asymmetry between child development and aging is inconsistent with general-factor lifespan theories of cognitive development and suggests that specific mechanisms underlying visual identification during child development and aging are different.     

Visual search across the life span

Gains and losses in visual search were studied across the life span in a representative sample of 298 individuals from 6 to 89 years of age. Participants searched for single-feature and conjunction targets of high or low eccentricity. Search was substantially slowed early and late in life, age gradients were more pronounced in conjunction than in feature search, and all age groups were uniformly affected by eccentricity manipulations. However, developmental and aging trends were distinctly asymmetrical: Children's performance was particularly affected by the mere presence of distractors; whereas in late life, performance was particularly impaired on target-absent trials and with increasing numbers of distractors. The implications for life span theories of cognitive and attentional development and for cognitive-speed and inhibitory-control accounts are discussed.     

Global self-esteem across the life span

This study provides a comprehensive picture of age differences in self-esteem from age 9 to 90 years using cross-sectional data collected from 326,641 individuals over the Internet. Self-esteem levels were high in childhood, dropped during adolescence, rose gradually throughout adulthood, and declined sharply in old age. This trajectory generally held across gender, socioeconomic status, ethnicity, and nationality (U.S. citizens vs. non-U.S. citizens). Overall, these findings support previous research, help clarify inconsistencies in the literature, and document new trends that require further investigation.     

Executive function across the life span

The development and determinants of executive function (EF) were studied in children (mean age=8.8 years), young adults ( M= 22.3 years), and elderly adults (M = 7 years). EF was indexed by perseverative responding on two bidimensional sorting tasks (Visually Cued Color-Shape task and Auditorily Cued Number-Numeral task), and age-related changes in EF were considered in relation to estimates of conscious vs. unconscious memory that were obtained using the process dissociation procedure (PDP). Results revealed the rise and fall of EF across the life span, with significant quadratic trends found for performance on both sorting tasks and for the conscious recollection component (C) of the PDP task. Regression analyses indicated that PDP estimates of conscious memory accounted for variation in performance on the visual sorting task, but not on the auditory sorting task. The findings are discussed in terms of their implications for hierarchical models of EF and its development.     

Perceptual asymmetry for chimeric stimuli in children with early unilateral brain damage

The present study used a chimeric stimuli task to assess the magnitude of the left-hemispace bias in children with congenital unilateral brain damage (n = 46) as compared to typically developing matched controls (n = 46). As would be expected, controls exhibited a significant left-hemispace bias. In the presence of left hemisphere (LH) damage, the left-hemispace preference was found to be present, but attenuated, whereas right hemisphere (RH) damage resulted in a less lateralized process. Examination of lesion severity revealed that large lesions in the RH were associated with a reversal of the typical left-hemispace bias, while small lesions resulted in a left bias approximating that of controls. In contrast, the left-hemispace preference in children with LH damage was similar across lesion size. We conclude that damage to either hemisphere early in brain development may alter hemispheric preference for processing of nonverbal stimuli, and that at least in the case of RH damage, alteration of the normal perceptual asymmetry may depend on the interaction between lesion side and severity.     

Naming ability across the adult life span

Abstract

Longitudinal performance on the Boston Naming Test (BNT) was evaluated in 53 normal subjects aged 30 to 79 who were each tested three times over a 7-year span. Naming performance showed a significant decline over time that was greatest for the oldest subjects. These results confirm that decline in naming is a real phenomenon in normal aging that cannot be attributable primarily to cohort effects. We conclude that the changes in naming ability across the life span reflect more than simply a breakdown in lexical retrieval and that perceptual and semantic processing may be implicated.     

Stability of self-esteem across the life span

Two studies examined the rank-order stability of self-esteem from age 6 to 83: Study 1 was a meta-analysis of 50 published articles (N = 29,839) and Study 2 analyzed data from 4 large national studies (N = 74,381). Self-esteem showed substantial continuity over time (disattenuated correlations ranged from the .50s to .70s), comparable to the stability found for personality traits. Both studies provided evidence for a robust developmental trend: Self-esteem stability was low during childhood, increased throughout adolescence and young adulthood, and declined during midlife and old age. This trend could not be explained by age differences in the reliability of self-esteem measures, and generally replicated across gender, ethnicity, self-esteem scale, nationality (U.S. vs. non-U.S.), and year of publication.     

Emotional experience in everyday life across the adult life span

Age differences in emotional experience over the adult life span were explored, focusing on the frequency, intensity, complexity, and consistency of emotional experience in everyday life. One hundred eighty-four people, age 18 to 94 years, participated in an experience-sampling procedure in which emotions were recorded across a 1-week period. Age was unrelated to frequency of positive emotional experience. A curvilinear relationship best characterized negative emotional experience. Negative emotions declined in frequency until approximately age 60, at which point the decline ceased. Individual factor analyses computed for each participant revealed that age was associated with more differentiated emotional experience. In addition, periods of highly positive emotional experience were more likely to endure among older people and periods of highly negative emotional experience were less stable. Findings are interpreted within the theoretical framework of socioemotional selectivity theory.     

Nasal trigeminal chemosensitivity across the adult life span

Individuals can determine the side of the nose that receives an odorant during unilateral presentation (lateralize) if endings of the trigeminal nerve are stimulated. By using psychophysical methods, olfactory detection and trigeminal lateralization thresholds for 1-butanol were obtained from 142 individuals ranging in age from 20 to 89 year. Sensitivity in both chemosensory pathways declined with advancing age, especially in people older than 60 years.     

Self-concept differentiation across the adult life span.

This study used 2 measures to examine 158 adults' (80 men, 78 women; ages 20 to 88 years) self-concept differentiation (SCD) across 5 role-specific self-representations. Findings revealed that the 2 measures did not assess SCD in similar ways and that they showed different associations with age. Specifically, the 1st measure was not significantly related to age, whereas the 2nd measure showed a curvilinear, U-shaped association with age. The 2nd SCD index also showed significant associations with several measures of emotional adjustment and 6 dimensions of psychological well-being. Additional analyses showed that age moderated the associations between SCD and positive and negative psychological well-being. A high level of SCD was associated with lower positive and higher negative psychological well-being for both young and older adults. However, this effect was significantly more pronounced in older adults.     

Personality and obesity across the adult life span

Personality traits contribute to health outcomes, in part through their association with major controllable risk factors, such as obesity. Body weight, in turn, reflects our behaviors and lifestyle and contributes to the way we perceive ourselves and others. In this study, the authors use data from a large (N = 1,988) longitudinal study that spanned more than 50 years to examine how personality traits are associated with multiple measures of adiposity and with fluctuations in body mass index (BMI). Using 14,531 anthropometric assessments, the authors modeled the trajectory of BMI across adulthood and tested whether personality predicted its rate of change. Measured concurrently, participants higher on Neuroticism or Extraversion or lower on Conscientiousness had higher BMI; these associations replicated across body fat, waist, and hip circumference. The strongest association was found for the impulsivity facet: Participants who scored in the top 10% of impulsivity weighed, on average, 11Kg more than those in the bottom 10%. Longitudinally, high Neuroticism and low Conscientiousness, and the facets of these traits related to difficulty with impulse control, were associated with weight fluctuations, measured as the variability in weight over time. Finally, low Agreeableness and impulsivity-related traits predicted a greater increase in BMI across the adult life span. BMI was mostly unrelated to change in personality traits. Personality traits are defined by cognitive, emotional, and behavioral patterns that likely contribute to unhealthy weight and difficulties with weight management. Such associations may elucidate the role of personality traits in disease progression and may help to design more effective interventions.     

Competitiveness across the life span: the feisty fifties

Existing theories on life span changes in confidence or motivation suggest that individuals' preferences to enter competitive situations should gradually decline with age. We examined competitive preferences in a field experiment using real financial stakes in 25- to 75-year-olds (N = 543). The critical dependent variable was whether participants chose to perform a simple mental arithmetic task either under a piece-rate payment schedule (i.e., $.25 per solved item) or a competitive payment schedule ($.50 per solved item if the overall score is better than that of a randomly selected opponent, $0 otherwise). Results revealed that competitive preferences increased across the life span until they peaked around age 50, and dropped thereafter. We also found that throughout, men had a substantially larger preference for competing than women-extending previous findings on college-aged participants. The age/gender differences in preferences were neither accounted for by actual differences in performance nor individuals' subjective confidence. This first systematic attempt to characterize age differences in competitive behavior suggests that a simple decline conception of competitiveness needs to be reconsidered.     

Control across the life span: A model for understanding self-direction

A comprehensive four-factor interactive model on physical, psychological, and environmental processes related to the sense of control is presented for adult development with an emphasis on later life. The four experienced components are (1) control from within oneself, (2) control over oneself, (3) control over the environment, and (4) control from the environment. Control over oneself and over the environment measure self-directed control, while control from within oneself and from the environment measure nonself-directed control. Coping (a bidimensional control scale) measures control from powerlessness and suicide to overcontrolling. Findings confirm a significant loss of coping in an older cohort group from a white, rural sample composed primarily of single subjects with low coping representing a significant drop in self-directed behavior. A discussion of the relationship between self-direction and health in the older cohort group follows.     

A model of cognitive development across the life span

A model of cognitive development across the life span was proposed. A distinction was drawn between an individual's unexercised potential, which refers to the level of performance that would be expected if the individual had no exercise and/or training on the ability in question, and an individual's optimally-exercised potential, which refers to the level of performance that would be expected if the individual had optimal exercise and training. Both unexercised and optimally-exercised potential levels were proposed to increase with age up to early adulthood and decrease gradually thereafter. The region between the two types of potential, which was also suggested to increase during childhood and decrease during later adulthood, indicates the extent to which exercise and/or training can affect performance. This model was shown to be consistent with a number of different types of empirical findings.     

World benevolence beliefs and well-being across the life span

Do people's worldviews change across the life course? Beliefs in the benevolence (goodness) of the world and their relations with age and well-being were examined in a 2-year study of a nationally representative sample (N = 2,138) ranging in age from 18 to 101 years. Multilevel modeling analyses controlling for demographics, mental health history, prior experience with stressful life events, and other key beliefs indicated that benevolence beliefs were positively associated with well-being and that these associations were stronger with increasing age. Analyses also demonstrated that individuals' benevolence beliefs increased during the study, were positively associated with age, and increased with the experience of bereavement, although they declined with the experience of other negative events. Age-related worldview change may be a part of life-span adaptation.     

Adults' conceptions of intelligence across the adult life span.

To examine whether young, middle-aged, and older adults view the concept of intelligent person as similar or different during adulthood, 140 adults of various ages rated how likely it would be for individuals of average and exceptional intelligence at 30, 50, and 70 years of age to be engaged in behaviors previously identified by adults as characterizing adult intelligence. Adults perceived more similarity between exceptionally intelligent prototypes of closer ages (i.e., 30 and 50 and 50 and 70). Intelligence was perceived to consist of interest and ability to deal with novelty, everyday competence, and verbal competence--dimensions that were perceived to be differentially important for different-aged prototypes and by individuals of different ages. Participants' conceptions also included the idea that intelligence is malleable and that abilities differentially increase or decrease across the life span.