Everyday cognition: age and intellectual ability correlates

The primary aim of this study was to examine the relationship between a new battery of everyday cognition measures, which assessed 4 cognitive abilities within 3 familiar real-world domains, and traditional psychometric tests of the same basic cognitive abilities. Several theoreticians have argued that everyday cognition measures are somewhat distinct from traditional cognitive assessment approaches, and the authors investigated this assertion correlationally in the present study. The sample consisted of 174 community-dwelling older adults from the Detroit metropolitan area, who had an average age of 73 years. Major results of the study showed that (a) each everyday cognitive test was strongly correlated with the basic cognitive abilities; (b) several basic abilities, as well as measures of domain-specific knowledge, predicted everyday cognitive performance; and (c) everyday and basic measures were similarly related to age. The results suggest that everyday cognition is not unrelated to traditional measures, nor is it less sensitive to age-related differences.     

Nonlinear blood pressure effects on cognition in old age: separating between-person and within-person associations

Midlife hypertension is associated with increased risk of cognitive impairment in later life. The association between blood pressure (BP) in older ages and cognition is less clear. In this study we provide estimates of between-person and within-person associations of BP and cognition in a population-based sample (N = 382) followed from age 70 across 12 occasions over 30 years. Between-person associations refer to how individual differences in BP relates to individual differences in cognition. Within-person associations refer to how individual and time specific changes in BP relate to variation in cognition. Hierarchical linear models were fitted to data from three cognitive measurements (verbal ability, spatial ability, and perceptual speed) while accounting for demographic and health-related covariates. We found consistent nonlinear between-person associations between diastolic BP (DBP) and cognition, such that both low (<75 mmHg) and high (>95 mmHg) pressure were associated with poorer cognition. Within-person decreases in systolic BP (SBP) and DBP were associated with decreases in perceptual speed. Notably, between-person and within-person estimates did not reveal similar associations, suggesting the need to separate the two effects in the analysis of associations between BP and cognition in old age.     

Social cognition and its neural correlates in schizophrenia and autism

The study of social cognition in psychiatric disorders has become increasingly popular in recent years. This is due to the its proposed link to social functioning and the inability of general neurocognitive skills to explain the spectrum of impairments observed in patients. This article reviews research into two of the processes thought to underlie social cognition (emotion perception and theory of mind) in schizophrenia and autism. This is followed by a look at neuroimaging studies and their efforts to localize the neural correlates of emotion perception and theory of mind in the two disorders. We concluded that while a specific impairment in emotion perception and theory of mind skills cannot be generalized to all individuals with autism and schizophrenia, there are subpopulations that have lingering deficits of social cognition tasks. Neuroimaging work consistently points to the involvement of the fusiform gyrus and amygdala in emotion processing, while the medial prefrontal and frontal cortex are implicated in tasks invoking theory of mind. We propose that deficits of social cognition may benefit from cognitive remediation therapy and pharmacological cognitive enhancers.     

Typical intellectual engagement and cognition in old age

Typical Intellectual Engagement (TIE) comprises the preference to engage in cognitively demanding activities and has been proposed as a potential explanatory variable of individual differences in cognitive abilities. Little is known, however, about the factorial structure of TIE, its relations to socio-demographic variables, and its influence on intellectual functioning in old age. In the present study, data of 364 adults (65-81 years) from the Zurich Longitudinal Study on Cognitive Aging (ZULU) were used to investigate the factorial structure of TIE and to examine the hypothesis that TIE is associated more strongly with crystallized intelligence than with fluid intelligence in old age. A measurement model of a second order factor based on a structure of four correlated first order factors (Reading, Problem Solving, Abstract Thinking, and Intellectual Curiosity) evinced an excellent fit. After controlling for age, sex, and formal education, TIE was more strongly associated with crystallized intelligence than with fluid intelligence, comparable to results in younger persons. More detailed analyses showed that this association is mostly defined via Reading and Intellectual Curiosity.     

Neurogenesis decreases with age in the canine hippocampus and correlates with cognitive function

New neurons are continually produced in the adult mammalian brain from progenitor cells located in specific brain regions, including the subgranular zone (SGZ) of the dentate gyrus of the hippocampus. We hypothesized that neurogenesis occurs in the canine brain and is reduced with age. We examined neurogenesis in the hippocampus of five young and five aged animals using doublecortin (DCX) and bromodeoxyuridine (BrdU) immunostaining. The total unilateral number of new neurons in the canine SGZ and granule cell layer (GCL) was estimated using stereological techniques based upon unbiased principles of systematic uniformly random sampling. Animals received 25mg/kg of BrdU once a day for 5 days and were euthanized 9 days after the last injection. We found evidence of neurogenesis in the canine brain and that cell genesis and neurogenesis are greatly reduced in the SGZ/GCL of aged animals compared to young. We further tested the hypothesis that an antioxidant fortified food or behavioral enrichment would improve neurogenesis in the aged canine brain and neurogenesis may correlate with cognitive function. Aged animals were treated for 2.8 years and tissue was available for six that received the antioxidant food, five that received the enrichment and six receiving both treatments. There were no significant differences in the absolute number of DCX or DCX-BrdU neurons or BrdU nuclei between the treatment groups compared to control animals. The number of DCX-positive neurons and double-labeled DCX-BrdU-positive neurons, but not BrdU-positive nuclei alone, significantly correlated with performance on several cognitive tasks including spatial memory and discrimination learning. These results suggest that new neurons in the aged canine dentate gyrus may participate in modulating cognitive functions.     

Global and domain-specific changes in cognition throughout adulthood

Normative adult age-related decrements are well documented for many diverse forms of effortful cognitive processing. However, it is currently unclear whether each of these decrements reflects a distinct and independent developmental phenomenon, or, in part, a more global phenomenon. A number of studies have recently been published that show moderate to large magnitudes of positive relations among individual differences in rates of changes in different cognitive variables during adulthood. This suggests that a small number of common dimensions or even a single common dimension may underlie substantial proportions of individual differences in aging-related cognitive declines. This possibility was directly examined using data from 1,281 adults 18-95 years of age who were followed longitudinally over up to 7 years on 12 different measures of effortful processing. Multivariate growth curve models were applied to examine the dimensionality of individual differences in longitudinal changes. Results supported a hierarchical structure of aging-related changes, with an average of 39% of individual differences in change in a given variable attributable to global (domain-general) developmental processes, 33% attributable to domain-specific developmental processes (abstract reasoning, spatial visualization, episodic memory, and processing speed), and 28% attributable to test-specific developmental processes. Although it is often assumed that systematic and pervasive sources of cognitive decline only emerge in later adulthood, domain-general influences on change were apparent for younger (18-49 years), middle aged (50-69 years), and older (70-95 years) adults.     

When time is running out: changes in positive future perception and their relationships to changes in well-being in old age

How optimistically individuals view their future and what they expect from it has often been studied in younger adults. Less attention has been paid to future perceptions in older adults whose future is temporally limited. Using longitudinal data from the Berlin Aging Study, the authors examined whether future orientation and optimism change in older adults (70-104 years) and whether changes in future perception precede changes in well-being. With advancing age participants reported fewer future plans and less optimism. Those changes were related to changes in well-being with partial support for a lead-lag relationship.     

Brain-Age quotient: age and education correlates.

The Brain-Age Quotient (BAQ) of Reitan has been proposed as a means of studying age-related cognitive differences. This study examined age and education correlates of the BAQ and a BAQ short form. A heterogeneous group of 100 subjects were selected from the neuropsychological testing case records published by Golden, Osmon, Moses, and Berg in 1981, Boll (undated), and Reitan (undated). Results suggest the BAQ and the BAQ short form are not significantly correlated with age and education.     

Duration discrimination in the context of age,sex, and cognition

It has been proposed that the perception of very short duration is governed by sensory mechanisms, whereas the perception of longer duration depends on cognitive capacities. Four duration discrimination tasks (modalities: visual, auditory; base duration: 100 ms, 1000 ms) were used to study the relation between time perception, age, sex, and cognitive abilities (alertness, visual and verbal working memory, general fluid reasoning) in 100 subjects aged between 21 and 84 years. Temporal acuity was higher (Weber fractions are lower) for longer stimuli and for the auditory modality. Age was related to the visual 100 ms condition only, with lower temporal acuity in elder participants. Alertness was significantly related to auditory and visual Weber fractions for shorter stimuli only. Additionally, visual working memory was a significant predictor for shorter visual stimuli. These results indicate that alertness, but also working memory, are associated with temporal discrimination of very brief duration.     

Socialization and cognition in children between the age of 18 and 24 months

A cross-cultural study of mother–child dyads was set up to test the hypothesis that sociocultural differences, mediated by variations of maternal intervention, influence the way in which the child manipulates objects and, thereby, his cognitive and social competences. Two series of observations were conducted with three groups of children aged 18–24 months (15 from the American middle class, 15 from French families and 15 from North African families—the last two groups both underprivileged): (a) ‘naturalistic’ observations of two systems of interaction (child–mother and child–children interaction) showed that each child is characterized by one type of object manipulation (protected, induced, activated or autonomous) and that maternal intervention varies with the sociocultural background; assessment of the child's behavioural sequences unravelled his strategies for solving and avoiding conflicts with his peers; (b) observations of the child with a standardized material permitted an evaluation of his cognitive competences for spontaneous problem-solving. Regarding the assumptions of our hypothesis, the results furnish the following conclusions: (1) social and cognitive competences are related to the object manipulation type. In all samples, children characterized by ‘activated’ and ‘autonomous’ manipulation obtain the better results; (2) maternal intervention differs among the samples depending on the sociocultural background; these differences (limitation and physical contact) do not correspond to differences in types of manipulation; (3) type of manipulation is an interactive construction; it characterizes the functioning of the mother–child dyad and its prevailing dynamics between permanence and change. ©1997 by John Wiley & Sons, Ltd.     

Cross-sectional age differences and longitudinal age changes of personality in middle adulthood and old age

The present study examines different aspects of personality continuity (or change) in middle adulthood and old age both cross-sectionally and longitudinally. The sample comprised 445 middle-aged (42-46 years) and 420 older (60-64 years) participants, reassessed after a 4-year interval. Personality was measured using the NEO-FFI personality inventory. After having established strict factorial invariance, factor covariances were found to be equal for both age groups and at both testing occasions, indicating perfect structural continuity of personality. A number of age differences in personality emerged at both measurement occasions. Longitudinally, in both age groups, an average decline in Neuroticism was observed. Longitudinal stability coefficients were around .80 in middle-aged and old participants, implying high, but not perfect, differential continuity. With respect to continuity of divergence, statistically significant cross-sectional age differences were found for the variance of Openness at both measurement occasions. Eventually, concerning specific versus general continuity, a variety of medium effect-sized correlated changes in the Big Five personality domains across the 4-year period was established, implying that personality changes share a certain amount of commonality.     

Executive functions after age 5: Changes and correlates

Research and theorizing on executive function (EF) in childhood has been disproportionately focused on preschool age children. This review paper outlines the importance of examining EF throughout childhood, and even across the lifespan. First, examining EF in older children can address the question of whether EF is a unitary construct. The relations among the EF components, particularly as they are recruited for complex tasks, appear to change over the course of development. Second, much of the development of EF, especially working memory, shifting, and planning, occurs after age 5. Third, important applications of EF research concern the role of school-age children’s EF in various aspects of school performance, as well as social functioning and emotional control. Future research needs to examine a more complete developmental span, from early childhood through late adulthood, in order to address developmental issues adequately.     

Paranormal beliefs: their dimensionality and correlates

Lack of conceptual clarity and multivariate empirical studies has troubled research on superstitious, magical and paranormal beliefs. We defined paranormal beliefs as beliefs in physical, biological or psychological phenomena that feature core ontological properties of another ontological category. The aim was to bring together a range of beliefs and their potential correlates, to analyse whether the beliefs form independent subsets, and to test a structural model of the beliefs and their potential correlates. The results (N = 3261) showed that the beliefs could be best described by one higher‐order factor. There were also four lower‐order factors of paranormal beliefs but their explanatory power was low. Magico‐religious beliefs were best explained by high intuitive thinking, a humanistic world view and low analytical thinking. Copyright © 2006 John Wiley & Sons, Ltd.     

Personality change profiles and changes in cognition among middle-aged and older adults

Research on the relationship between personality traits and cognitive abilities has primarily used cross-sectional designs and considered personality traits individually in relation to cognitive dimensions. This study (N = 2652) examined the relationship between Big Five personality change profiles and change in cognitive factors, episodic memory and executive functioning. Latent profile analysis was used to capture patterns of change across the Big Five traits. Three profiles of personality change were defined: Decreasers, Maintainers, and Increasers. The Decreasers declined more in episodic memory compared to the Increasers and Maintainers. Also, the Decreasers declined more in executive functioning compared to the Increasers, but not the Maintainers. The findings advance our understanding of the links between patterns of personality change and cognitive aging.     

Confirmatory reinforcement learning changes with age during adolescence

Understanding how learning changes during human development has been one of the long-standing objectives of developmental science. Recently, advances in computational biology have demonstrated that humans display a bias when learning to navigate novel environments through rewards and punishments: they learn more from outcomes that confirm their expectations than from outcomes that disconfirm them. Here, we ask whether confirmatory learning is stable across development, or whether it might be attenuated in developmental stages in which exploration is beneficial, such as in adolescence. In a reinforcement learning (RL) task, 77 participants aged 11–32 years (four men, mean age = 16.26) attempted to maximize monetary rewards by repeatedly sampling different pairs of novel options, which varied in their reward/punishment probabilities. Mixed-effect models showed an age-related increase in accuracy as long as learning contingencies remained stable across trials, but less so when they reversed halfway through the trials. Age was also associated with a greater tendency to stay with an option that had just delivered a reward, more than to switch away from an option that had just delivered a punishment. At the computational level, a confirmation model provided increasingly better fit with age. This model showed that age differences are captured by decreases in noise or exploration, rather than in the magnitude of the confirmation bias. These findings provide new insights into how learning changes during development and could help better tailor learning environments to people of different ages.

Research Highlights

• Reinforcement learning shows age-related improvement during adolescence, but more in stable learning environments compared with volatile learning environments.
• People tend to stay with an option after a win more than they shift from an option after a loss, and this asymmetry increases with age during adolescence.
• Computationally, these changes are captured by a developing confirmatory learning style, in which people learn more from outcomes that confirm rather than disconfirm their choices.
• Age-related differences in confirmatory learning are explained by decreases in stochasticity, rather than changes in the magnitude of the confirmation bias.

     

Cross-sectional and longitudinal relationships among age, cognition, and processing speed

Cross-sectional and longitudinal age effects on cognitive function were examined in 302 older adults followed longitudinally. Processing speed was related to cognitive performance at cross-section, and change in speed predicted within-person longitudinal cognitive decline. Statistical control of processing speed greatly reduced cross-sectional age effects but did not attenuate longitudinal aging effects. This difference in processing speed's ability to account for cross-sectional and longitudinal age effects is discussed in the context of theories of cognitive aging and methodological and statistical issues pertaining to the cross-sectional and longitudinal study of cognitive aging.     

On the specificity of face cognition compared with general cognitive functioning across adult age

Face cognition is considered a specific human ability, clearly differentiable from general cognitive functioning. Its specificity is primarily supported by cognitive-experimental and neuroimaging research, but recently also from an individual differences perspective. However, no comprehensive behavioral data are available, which would allow estimating lifespan changes of the covariance structure of face-cognition abilities and general cognitive functioning as well as age-differences in face cognition after accounting for interindividual variability in general cognition. The present study aimed to fill this gap. In an age-heterogeneous (18-82 years) sample of 448 adults, we found no factorial dedifferentiation between face cognition and general cognition. Age-related differences in face memory were still salient after taking into account changes in general cognitive functioning. Face cognition thus remains a specific human ability compared with general cognition, even until old age. We discuss implications for models of cognitive aging and suggest that it is necessary to include more explicitly special social abilities in those models.