Cognitive Neurorehabilitation of HIV-associated Neurocognitive Disorders: A Qualitative Review and Call to Action

Despite significant advances in the virologic management of HIV infection over the last two decades, effective treatments for HIV-associated neurocognitive disorders (HAND) remain elusive. While pharmacological interventions have yielded some success in improving neurocognitive outcomes in HIV, there is a dearth of rigorous studies examining the efficacy of cognitive rehabilitation for remediating HIV-associated neurocognitive impairment. This qualitative review summarizes and critiques the emerging literature on cognitive and behavioral treatments for HAND, which provides many reasons for optimism, but also has major limitations that underscore the scope of the work that lies ahead. Considering the notable real-world consequences of HAND, the development, validation, and clinical deployment of cognitive neurorehabilitation interventions tailored to the needs of persons living with HIV infection is a priority for clinical neuroAIDS investigators. In describing potential future directions for this endeavor, particular attention was paid to the application of cognitive neuropsychological principles in developing theory-driven approaches to managing HAND, improving everyday functioning, and enhancing HIV health outcomes.     

Semantic similarity, predictability, and models of sentence processing

The effects of word predictability and shared semantic similarity between a target word and other words that could have taken its place in a sentence on language comprehension are investigated using data from a reading time study, a sentence completion study, and linear mixed-effects regression modeling. We find that processing is facilitated if the different possible words that could occur in a given context are semantically similar to each other, meaning that processing is affected not only by the nature of the words that do occur, but also the relationships between the words that do occur and those that could have occurred. We discuss possible causes of the semantic similarity effect and point to possible limitations of using probability as a model of cognitive effort.     

What is the future for tool-specific generalized motor programs?

A key issue in cognitive sciences is to understand the cognitive bases of human tool use. Answers have been provided by two competing approaches. The manipulation-based approach assumes that humans can use tools because of the ability to store sensorimotor knowledge about how to manipulate tools. By contrast, for the reasoning-based approach, human tool use is based on the ability to reason about physical object properties. Recently, Caruana and Cuccio proposed a kind of reconciliation, based on the distinction between three types of abductive inference, involving a different contribution of motor and cognitive elements: Automatic abduction (motor + and cognitive-), abduction by selection (motor ± and cognitive±) and creative abduction (motor- and cognitive+). This perspective offers new interesting avenues. Nevertheless, it is also subject to several theoretical and epistemological limitations, which make it in its present form inappropriate for the study of the cognitive bases of human tool use. This article aims to discuss these limitations.     

Motivation towards closure and cognitive processes: An individual differences approach

Two studies (N = 212) examined the relationships between elementary cognitive processes and individual differences in the need for cognitive closure. The results indicated that the need for closure is linked with certain cognitive deficits, specifically a restricted pool of cognitive resources allocated to a current activity. It was also found that these cognitive limitations tend to be compensated for by a particularly efficient process of information-selection from the environment. However, the selection process is costly, thus in a situation of drainage of cognitive resources its effectiveness also drops and the selection advantage of high (vs. low) need for closure individuals is eliminated.     

Fatigue, sleep loss, and confidence in judgment

Sixty-four adults participated in a study examining the accuracy of metacognitive judgments during 28 hr of sleep deprivation (SD) and continuous cognitive work. Three tasks were studied (perceptual comparison, general knowledge, and mental addition), collectively spanning a range of cognitive abilities and levels of susceptibility to SD. Subjective and objective measures of sleepiness confirmed the expected patterns of increasing fatigue with SD. Participants displayed differing levels of metacognitive abilities across tasks, but traditional indices of the confidence-accuracy relation (i.e., calibration, resolution, over- and underconfidence), as well as the accuracy of pre- and posttask estimates of performance, remained stable over the SD period. The findings suggest that people can accurately assess their own cognitive performance when deprived of 1 night of sleep and that this ability need not be based on subjective estimates of sleepiness. The implications and limitations of the study are discussed and directions for future research are proposed.     

Motivation towards closure and cognitive processes: An individual differences approach

Two studies (N = 212) examined the relationships between elementary cognitive processes and individual differences in the need for cognitive closure. The results indicated that the need for closure is linked with certain cognitive deficits, specifically a restricted pool of cognitive resources allocated to a current activity. It was also found that these cognitive limitations tend to be compensated for by a particularly efficient process of information-selection from the environment. However, the selection process is costly, thus in a situation of drainage of cognitive resources its effectiveness also drops and the selection advantage of high (vs. low) need for closure individuals is eliminated.     

Is there a trade-off between cognitive and motor recovery after traumatic brain injury due to competition for limited neural resources?

The status of neurorehabilitation for traumatic brain injury (TBI) is under active debate because of a dearth of research findings demonstrating effectiveness. This may be due, in part, to limitations in our understanding of basic mechanisms of cognitive and motor recovery,including those that might impede recovery. In this regard, we examined whether overall recovery following TBI might be undermined by competition between cognitive and motor functions for finite neural resources during recovery. In this preliminary study, 21 moderately and severely impaired patients were administered cognitive and motor assessments at 1, 4, and 12 months post-TBI, and recovery of cognitive and motor functions was measured using regression residuals. Negative correlations between recovery of cognitive versus motor functions were used as the index of competition. We found suggestive evidence that there may indeed be a trade-off between the recovery of cognitive and motor functions after TBI. Implications for rehabilitation are discussed.     

Neuroanatomical substrates of age-related cognitive decline

There are many reports of relations between age and cognitive variables and of relations between age and variables representing different aspects of brain structure and a few reports of relations between brain structure variables and cognitive variables. These findings have sometimes led to inferences that the age-related brain changes cause the age-related cognitive changes. Although this conclusion may well be true, it is widely recognized that simple correlations are not sufficient to warrant causal conclusions, and other types of correlational information, such as mediation and correlations between longitudinal brain changes and longitudinal cognitive changes, also have limitations with respect to causal inferences. These issues are discussed, and the existing results on relations of regional volume, white matter hyperintensities, and diffusion tensor imaging measures of white matter integrity to age and to measures of cognitive functioning are reviewed. It is concluded that at the current time the evidence that these aspects of brain structure are neuroanatomical substrates of age-related cognitive decline is weak. The final section contains several suggestions concerning measurement and methodology that may lead to stronger conclusions in the future.     

Depression and Anxiety: Integrating the Tripartite and Cognitive Content-Specificity Assessment Models

The cognitive content-specificity hypothesis proposes that depression and anxiety can be discriminated on the basis of unique cognitive profiles. Alternatively, the Tripartite model suggests that, although depression and anxiety share a general distress factor, anhedonia is a characteristic of depression with anxious arousal a characteristic of anxiety. Past research devoted to integrating these two models has been limited in a number of ways. To remedy these limitations, this study attempted to assess the complete Tripartite model and used a multidimensional cognitive assessment tool to handle the heterogeneity of anxious cognitive content. Results on data collected from 411 clients seeking services at a university counseling center suggested that a one-to-one mapping between Tripartite dimensions and cognitive content was possible. Further, variables from each model simultaneously explained unique variance in depression and anxiety ratings.     

Memories, fantasies, archetypes: an exploration of some connections between cognitive science and analytical psychology

The value of cognitive science as a means of investigating psychodynamic theory and practice is discussed and the limitations of this approach are described. Research findings from cognitive science are drawn on to clarify the nature of memory, which is seen to be a mixture of reproduction and reconstruction and the concepts of true and false memory are explored in this light. The part played by implicit memory and internal working models in producing transference is also examined. New ways of conceptualizing fantasy, which describes it as another facet of internal working models, and the role of transgenerational transmission of attachment patterns in creating internal working models are explored. The nature of archetypes is considered in the light of cognitive science research and a minimalist model is proposed, in which they can be likened to image schemas, that is, primitive conceptual structures that exist in a form which can never be experienced directly or indirectly.     

Intrinsic motivation,external reward,and their effect on overall motivation and performance

An unresolved debate lingers concerning the effect of performance-contingent rewards on motivation and performance. Behavioral psychology and economics suggest that performance-contingent rewards improve performance. In contrast, cognitive evaluation theory predicts that performance-contingent rewards undermine motivation and performance. We discuss the predictions of these two streams and develop an experiment that resolves the limitations of previous studies by using a new measure of intrinsic motivation: self-selection into a specific area of knowledge, as revealed by choice of academic major. Students from mathematics-related and literature-related areas were selected and randomly assigned to math and English language tests. Participants received a participation fee or a performance-contingent payment in addition to a fee. Both performance-contingent rewards and intrinsic motivation improved motivation and performance, in contrast with cognitive evaluation theory’s predictions.     

The past,present, and future of computational models of cognitive development

Does modeling matter? We address this question by providing a broad survey of the computational models of cognitive development that have been proposed and studied over the last three decades. We begin by noting the advantages and limitations of computational models. We then describe four key dimensions across which models of development can be organized and classified. With this taxonomy in hand, we focus on how the modeling enterprise has evolved over time. In particular, we separate the timeline into three overlapping historical waves and highlight how each wave of models has not only been shaped by developmental theory and behavioral research, but in return also provided valuable insights and innovations to the study of cognitive development.     

Does working memory training work? The promise and challenges of enhancing cognition by training working memory

A growing body of literature shows that one's working memory (WM) capacity can be expanded through targeted training. Given the established relationship between WM and higher cognition, these successful training studies have led to speculation that WM training may yield broad cognitive benefits. This review considers the current state of the emerging WM training literature, and details both its successes and limitations. We identify two distinct approaches to WM training, strategy training and core training, and highlight both the theoretical and practical motivations that guide each approach. Training-related increases in WM capacity have been successfully demonstrated across a wide range of subject populations, but different training techniques seem to produce differential impacts upon the broader landscape of cognitive abilities. In particular, core WM training studies seem to produce more far-reaching transfer effects, likely because they target domain-general mechanisms of WM. The results of individual studies encourage optimism regarding the value of WM training as a tool for general cognitive enhancement. However, we discuss several limitations that should be addressed before the field endorses the value of this approach.     

Procrastination as self‐regulation failure of performance: effects of cognitive load,self‐awareness,and time limits on ‘working best under pressure’

Effects of cognitive load, objective self‐awareness and time limits on the self‐regulation of performance speed and accuracy were investigated between procrastinators and non‐procrastinators. In experiment 1 chronic procrastinators completed fewer items (slow speed) and made more errors (less accuracy) than non‐procrastinators under high but not low cognitive load conditions when the time span was limited and brief. In experiment 2 chronic procrastinators performed slower than non‐procrastinators under a 2 second, but not under no limit, 1 second, or 4 second time limit conditions. Chronic procrastinators compared to non‐procrastinators also performed more slowly and made more performance errors under objective self‐awareness conditions regardless of the length of time. These experiments indicate that chronic procrastinators regulate ineffectively their performance speed and accuracy when they ‘work under pressure’ (defined by high cognitive load, objective self‐awareness, and imposed time limitations). Copyright © 2001 John Wiley & Sons, Ltd.     

The Effects of Cognitive Development on the Use of Cognitive Behavioral Techniques with Children

The present paper hypothesizes that, for children, cognitive behavior therapy techniques cannot be applied without first determining the cognitive developmental level of information processing that is being used by the client. Demand requirements of various cognitive behavioral techniques are compared with information processing limitations described by developmental theorists to hypothesize a continuum of cognitive behavioral interventions for children.     

Relations among categorization, induction, recognition, and similarity: comment on Sloutsky and Fisher (2004)

V. M. Sloutsky and A. V. Fisher reported 5 experiments documenting relations among categorization, induction, recognition, and similarity in children as well as adults and proposed a new model of induction, SINC (similarity, induction, categorization). Those authors concluded that induction depends on perceptual similarity rather than conceptual knowledge. Despite the useful contributions of this work, there are some important limitations. The experimental designs examined a limited range of phenomena that are not the most revealing about the use of nonperceptual information. The main results involved a simple triad task, for which the SINC model's predictions are equivalent to the predictions of previous models of inductive reasoning. It is also unclear whether the SINC model can account for the observed relations between similarity and recognition. Implications for future work on induction and related cognitive activities are discussed.     

Neuroimaging studies of the cerebellum: language, learning and memory

During the decade following a functional neuroimaging study of language that showed cerebellar involvement in a cognitive task, PET and fMRI studies have continued to provide evidence that the role of the cerebellum extends beyond that of motor control and that this structure contributes in some way to cognitive operations. In this review, we describe neuroimaging evidence for cerebellar involvement in working memory, implicit and explicit learning and memory, and language, and we discuss some of the problems and limitations faced by researchers who use neuroimaging to investigate cerebellar function. We also raise a set of outstanding questions that need to be addressed through further neuroimaging and behavioral experiments before differing functional accounts of cerebellar involvement in cognition can be resolved.     

Core self-evaluations interact with cognitive ability to predict academic achievement

Extant research suggests that core self-evaluations (CSE) is associated with various work-related criteria, but such research often focuses on main effects when predicting subjective outcomes. Drawing upon psychological theories involving self-concept and motivation, we investigated both the main and interactive effects of CSE and cognitive ability when predicting an objective outcome. Specifically, results indicated that high CSE strengthened the positive relation between cognitive ability and academic achievement. Study contributions and limitations are discussed.     

Core self-evaluations interact with cognitive ability to predict academic achievement

Extant research suggests that core self-evaluations (CSE) is associated with various work-related criteria, but such research often focuses on main effects when predicting subjective outcomes. Drawing upon psychological theories involving self-concept and motivation, we investigated both the main and interactive effects of CSE and cognitive ability when predicting an objective outcome. Specifically, results indicated that high CSE strengthened the positive relation between cognitive ability and academic achievement. Study contributions and limitations are discussed.