The unity and diversity of executive functions and their contributions to complex "Frontal Lobe" tasks: a latent variable analysis.

▪ Abstract The prefrontal cortex has long been suspected to play an important role in cognitive control, in the ability to orchestrate thought and action in accordance with internal goals. Its neural basis, however, has remained a mystery. Here, we propose that cognitive control stems from the active maintenance of patterns of activity in the prefrontal cortex that represent goals and the means to achieve them. They provide bias signals to other brain structures whose net effect is to guide the flow of activity along neural pathways that establish the proper mappings between inputs, internal states, and outputs needed to perform a given task. We review neurophysiological, neurobiological, neuroimaging, and computational studies that support this theory and discuss its implications as well as further issues to be addressed

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An integrative theory of prefrontal cortex function

Publisher Summary This chapter focuses on the modern notion of short-term memory, called working memory. Working memory refers to the temporary maintenance of information that was just experienced or just retrieved from long-term memory but no longer exists in the external environment. These internal representations are short-lived, but can be maintained for longer periods of time through active rehearsal strategies, and can be subjected to various operations that manipulate the information in such a way that makes it useful for goal-directed behavior. Working memory is a system that is critically important in cognition and seems necessary in the course of performing many other cognitive functions, such as reasoning, language comprehension, planning, and spatial processing. This chapter demonstrates the functional importance of dopamine to working memory function in several ways. Elucidation of the cognitive and neural mechanisms underlying human working memory is an important focus of cognitive neuroscience and neurology for much of the past decade. One conclusion that arises from research is that working memory, a faculty that enables temporary storage and manipulation of information in the service of behavioral goals, can be viewed as neither a unitary, nor a dedicated system. Data from numerous neuropsychological and neurophysiological studies in animals and humans demonstrates that a network of brain regions, including the prefrontal cortex, is critical for the active maintenance of internal representations.

Chapter 11 Working memory

Co-Planar Stereotaxic Atlas of the Human Brain—3-Dimensional Proportional System: An Approach to Cerebral Imaging, J. Talairach, P. Tournoux. Georg Thieme Verlag, New York (1988), 122 pp., 130 figs. DM 268

Attention and Effort

It is well established that the more we learn, the more we remember. It is also known that our ability to acquire new information changes with age. An important remaining issue for debate is whether the rate of forgetting depends on initial degree of learning. In two experiments, following the procedure used by Slamecka and McElree (Exp 3), we investigated the relationship between initial degree of learning and rate of forgetting in both younger and older adults. A set of 36 (Exp 1) and a set of 30 (Exp 2) sentences was presented four times. Forgetting was measured via cued recall at three retention intervals (30 s, 1 hr, and 24 hr). A different third of the original sentences was tested at each delay. The results of both experiments showed that initial acquisition is influenced by age. However, the rate of forgetting proved to be independent from initial degree of learning. The conclusion is that rates of forgetting are independent from initial degree of learning.

/pdf/rate-of-forgetting-is-independent-from-initial-degree-of-1n59gsp9.pdf

Rate of forgetting is independent from initial degree of learning across different age groups

Introduction to Working Memory

Cognitive Neuroscience: A reader

Recent findings demonstrate that selective retrieval practice (SRP), specifically the retrieval of subparts of material, not just retrieval of the entire encoded material, can enhance later memory performance. We present two experiments that investigated whether SRP enhances memory performance among older adults. We also examined to what extent this effect is enhanced by the level of integration of the studied material. We used a design that contrasts the performance of the groups in conditions with and without SRP. This design also allowed us to examine whether older adults present with faster forgetting compared to younger individuals when assessed over a long delay. In both experiments, participants were exposed to a learning phase in which they had to achieve a criterion of 70% correct recall and were then tested at 1 month. The SRP for the experimental group occurred 1 day and 1 week after the learning phase (the control group received no SRP). None of the items at 1-month delay was probed in the retrieval practice. Experiment 1 used integrated material (four short stories). Experiment 2 used less integrated material (16 sentences). Both age groups showed a decline in memory performance over 1 month, however, groups tested repeatedly showed better performance (irrespective of age or material). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The effect of selective retrieval practice on forgetting rates in younger and older adults.

There are two principal methods of studying aging, the longitudinal and the cross-sectional. The problem of practice effects is avoided if one uses a cross-sectional design in which different groups of people are sampled across the age range and their performance is measured on a single occasion. A solution to the problem is to combine longitudinal and cross-sectional approaches by adding a new cohort of participants at each test age. There is broad general agreement that working memory is susceptible to the effects of age, although it is not always clear exactly which aspects are most vulnerable. Digit span is relatively resistant whereas sentence span in which participants must process a sequence of sentences and then recall the final word does tend to be sensitive to aging, the degree of decrement is however less marked than one might expect.

Alan D. Baddeley

Papers

Rate of forgetting is independent from initial degree of learning across different age groups

Introduction to Working Memory

Cognitive Neuroscience: A reader

The effect of selective retrieval practice on forgetting rates in younger and older adults.

Memory and aging