Ulman Lindenberger

Sensory functioning and intelligence in old age: A strong connection

Relations among age, sensory functioning (i.e., visual and auditory acuity), and intelligence were examined in a heterogeneous, age-stratified sample of old and very old individuals (N = 156, M age = 84.9 years, age range = 70-103). Intelligence was assessed with 14 tests measuring 5 cognitive abilities (speed, reasoning, memory, knowledge, and fluency). Together, visual and auditory acuity accounted for 49.2% of the total and 93.1% of the age-related reliable variance in intelligence. The data were consistent with structural models in which age differences in intelligence, including speed, are completely mediated by differences in vision and hearing. Results suggest that sensory functioning is a strong late-life predictor of individual differences in intellectual functioning. Explanations are discussed, including the possibility that visual and sensory acuity are indicators of the physiological integrity of the aging brain (common cause hypothesis).

Aging cognition: from neuromodulation to representation

Basic cognitive functions, such as the abilities to activate, represent, maintain, focus and process information, decline with age. A paradigm shift towards cross-level conceptions is needed in order to obtain an integrative understanding of cognitive aging phenomena that cuts across neural, information-processing, and behavioral levels. We review empirical data at these different levels, and computational theories proposed to enable their integration. A theoretical link is highlighted, relating deficient neuromodulation with noisy information processing, which might result in less distinctive cortical representations. These less distinctive representations might be implicated in working memory and attentional functions that underlie the behavioral manifestations of cognitive aging deficits.

Adult age differences in task switching.

Age differences in 2 components of task-set switching speed were investigated in 118 adults aged 20 to 80 years using task-set homogeneous (e.g., AAAA ...) and task-set heterogeneous (e.g., AABBAABB ... ) blocks. General switch costs were defined as latency differences between heterogeneous and homogeneous blocks. whereas specific switch costs were defined as differences between switch and nonswitch trials within heterogeneous blocks. Both types of costs generalized over verbal, figural, and numeric stimulus materials; were more highly correlated to fluid than to crystallized abilities; and were not eliminated after 6 sessions of practice, indicating that they reflect basic and domain-general aspects of cognitive control. Most important, age-associated increments in costs were significantly greater for general than for specific switch costs, suggesting that the ability to efficiently maintain and coordinate 2 alternating task sets in working memory instead of 1 is more negatively affected by advancing age than the ability to execute the task switch itself.

The correlative triad among aging, dopamine, and cognition: Current status and future prospects

The brain neuronal systems defined by the neurotransmitter dopamine (DA) have since long a recognized role in the regulation of motor functions. More recently, converging evidence from patient studies, animal research, pharmacological intervention, and molecular genetics indicates that DA is critically implicated also in higher-order cognitive functioning. Many cognitive functions and multiple markers of striatal and extrastriatal DA systems decline across adulthood and aging. Research examining the correlative triad among adult age, DA, and cognition has found strong support for the view that age-related DA losses are associated with age-related cognitive deficits. Future research strategies for examining the DA-cognitive aging link include assessing (a) the generality/specificity of the effects; (b) the relationship between neuromodulation and functional brain activation; and (c) the release of DA during actual task performance.

Intellectual functioning in old and very old age: Cross-sectional results from the Berlin Aging Study

This study documents age trends, interrelations, and correlates of intellectual abilities in old and very old age (70-103 years) from the Berlin Aging Study (N = 516). Fourteen tests were used to assess 5 abilities: reasoning, memory, and perceptual speed from the mechanic (broad fluid) domain and knowledge and fluency from the pragmatic (broad crystallized) domain. Intellectual abilities had negative linear age relations, with more pronounced age reductions in mechanic than in pragmatic abilities. Interrelations among intellectual abilities were highly positive and did not follow the mechanic-pragmatic distinction. Sociobiographical indicators were less closely linked to intellectual functioning than sensory-sensorimotor variables, which predicted 59% of the total reliable variance in general intelligence. Results suggest that aging-induced biological factors are a prominent source of individual differences in intelligence in old and very old age.

FACES - A database of facial expressions in young, middle-aged, and older women and men : Development and validation

Faces are widely used as stimuli in various research fields. Interest in emotion-related differences and age-associated changes in the processing of faces is growing. With the aim of systematically varying both expression and age of the face, we created FACES, a database comprising N=171 naturalistic faces of young, middle-aged, and older women and men. Each face is represented with two sets of six facial expressions (neutrality, sadness, disgust, fear, anger, and happiness), resulting in 2,052 individual images. A total of N=154 young, middleaged, and older women and men rated the faces in terms of facial expression and perceived age. With its large age range of faces displaying different expressions, FACES is well suited for investigating developmental and other research questions on emotion, motivation, and cognition, as well as their interactions. Information on using FACES for research purposes can be found at http://faces.mpib-berlin.mpg.de.

Transformations in the Couplings Among Intellectual Abilities and Constituent Cognitive Processes Across the Life Span

Two-component theories of intellectual development over the life span postulate that fluid abilities develop earlier during child development and decline earlier during aging than crystallized abilities do, and that fluid abilities support or constrain the acquisition and expression of crystallized abilities. Thus, maturation and senescence compress the structure of intelligence by imposing age-specific constraints upon its constituent processes. Hence, the couplings among different intellectual abilities and cognitive processes are expected to be strong in childhood and old age. Findings from a population-based study of 291 individuals aged 6 to 89 years support these predictions. Furthermore, processing robustness, a frequently overlooked aspect of processing, predicted fluid intelligence beyond processing speed in old age but not in childhood, suggesting that the causes of more compressed functional organization of intelligence differ between maturation and senescence. Research on developmental changes in functional brain circuitry may profit from explicitly recognizing transformations in the organization of intellectual abilities and their underlying cognitive processes across the life span.

Walking While Memorizing: Age-Related Differences in Compensatory Behavior

This study investigated predictions of the life-span theory of selection, optimization, and compensation, focusing on different patterns of task priority during dual-task performance in younger and older adults. Cognitive (memorizing) and sensorimotor (walking a narrow track) performance were measured singly, concurrently, and when task difficulty was manipulated. Use of external aids was measured to provide another index of task priority. Before dual-task testing, participants received extensive training with each component task and external aid. Age differences in dual-task costs were greater in memory performance than in walking, suggesting that older adults prioritized walking over memory. Further, when given a choice of compensatory external aids to use, older adults optimized walking, whereas younger adults optimized memory performance. The results have broad implications for systemic theories of cognitive and sensorimotor aging, and the costs and benefits of assistive devices and environmental support for older populations.

Memory aging and brain maintenance

Episodic memory and working memory decline with advancing age. Nevertheless, large-scale population-based studies document well-preserved memory functioning in some older individuals. The influential ‘reserve’ notion holds that individual differences in brain characteristics or in the manner people process tasks allow some individuals to cope better than others with brain pathology and hence show preserved memory performance. Here, we discuss a complementary concept, that of brain maintenance (or relative lack of brain pathology), and argue that it constitutes the primary determinant of successful memory aging. We discuss evidence for brain maintenance at different levels: cellular, neurochemical, gray- and white-matter integrity, and systems-level activation patterns. Various genetic and lifestyle factors support brain maintenance in aging and interventions may be designed to promote maintenance of brain structure and function in late life.

A theoretical framework for the study of adult cognitive plasticity

Does plasticity contribute to adult cognitive development, and if so, in what ways? The vague and overused concept of plasticity makes these controversial questions difficult to answer. In this article, we refine the notion of adult cognitive plasticity and sharpen its conceptual distinctiveness. According to our framework, adult cognitive plasticity is driven by a prolonged mismatch between functional organismic supplies and environmental demands and denotes the brains capacity for anatomically implementing reactive changes in behavioral flexibility (i.e., the possible range of performance and function). We distinguish between 2 interconnected but distinct cognitive outcomes of adult cognitive plasticity: alterations in processing efficiency and alterations in representations. We demonstrate the usefulness of our framework in evaluating and interpreting (a) increments in frontal brain activations in the course of normal aging and (b) the effects of cognitive training in adulthood and old age. Finally, we outline new research questions and predictions generated by the present framework and recommend design features for future cognitive-training studies.