Restorative Neurology and Neuroscience - Volume 27, issue 5

Authors: Martin, M. | Zöllig, J.

Article Type: Research Article

DOI: 10.3233/RNN-2009-0490

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 371-373, 2009

Authors: Willis, Sherry L. | Schaie, K. Warner

Article Type: Research Article

Abstract: Purpose. To provide an overview of cognitive plasticity concepts and findings from a lifespan developmental perspective. Methods. After an evaluation of the general concept of cognitive plasticity, the most important approaches to study behavioral and brain plasticity are reviewed. This includes intervention studies, experimental approaches, cognitive trainings, the study of facilitating factors for strategy learning and strategy use, practice, and person-environment interactions. Transfer and durability of training-induced plasticity is discussed. Results. The …review indicates that methodological and conceptual advances are needed to improve the match between levels of behavioral and brain plasticity targeted in current developmental research and study designs. Conclusions. The results suggest that the emphasis of plasticity studies on treatment effectiveness needs to be complemented by a strong commitment to the grounding of the intervention in a conceptual framework. Show more

DOI: 10.3233/RNN-2009-0527

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 375-389, 2009

Authors: Goh, Joshua O. | Park, Denise C.

Article Type: Research Article

Abstract: A recent proposal called the Scaffolding Theory of Cognitive Aging (STAC) postulates that functional changes with aging are part of a lifespan process of compensatory cognitive scaffolding that is an attempt to alleviate the cognitive declines associated with aging. Indeed, behavioral studies have shown that aging is associated with both decline as well as preservation of selective cognitive abilities. Similarly, neuroimaging studies have revealed selective changes in the aging brain that reflect neural decline as well …as compensatory neural recruitment. While aging is associated with reductions in cortical thickness, white-matter integrity, dopaminergic activity, and functional engagement in posterior brain regions such as the hippocampus and occipital areas, there are compensatory increases in frontal functional engagement that correlate with better behavioral performance in older adults. In this review, we discuss these age-related behavioral and brain findings that support the STAC model of cognitive scaffolding and additionally integrate the findings on neuroplasticity as a compensatory response in the aging brain. As such, we also examine the impact of external experiences in facilitating neuroplasticity in older adults. Finally, having laid the foundation for STAC, we briefly describe a proposed intervention trial (The Synapse Program) designed to evaluate the behavioral and neural impact of engagement in lifestyle activities that facilitates successful cognitive scaffolding using a controlled experiment where older adult participants are randomly assigned to different conditions of engagement. Show more

DOI: 10.3233/RNN-2009-0493

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 391-403, 2009

Authors: Dahlin, Erika | Bäckman, Lars | Neely, Anna Stigsdotter | Nyberg, Lars

Article Type: Research Article

Abstract: Purpose: Several recent studies show that training can improve working memory (WM) performance. In this review, many issues related to WM training, such as neural basis, transfer effects, and age-related changes are addressed. Method: We focus on our own studies investigating training on tasks taxing the executive updating function and discuss our findings in relation to results from other studies investigating training of the executive component of WM. Results: The review confirms …positive behavioral effects of training on working memory. The most common neural pattern following training is fronto-parietal activity decreases. Increases in sub-cortical areas are also frequently reported after training, and we suggest that such increases indicate changes in the underlying skill following training. Transfer effects are in general difficult to demonstrate. Some studies show that older adults increase their performance after WM training. However, transfer effects are small or nonexistent in old age. Conclusions: The main finding in this review is that sub-cortical areas seem to have a critical role in mediating transfer effects to untrained tasks after at least some forms of working memory training (such as updating). Show more

Keywords: Fronto-parietal changes, subcortical changes, executive training, fMRI, transfer effects, aging

DOI: 10.3233/RNN-2009-0492

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 405-419, 2009

Authors: Zöllig, Jacqueline | Eschen, Anne

Article Type: Research Article

Abstract: Purpose. The present paper integrates two important aspects when studying compensation: (1) the knowledge about specific compensational mechanisms and (2) the consideration of lifelong changes in these mechanisms (i.e., plasticity of compensation). Hence, the paper addresses the questions (a) which neural networks are supporting successful cognitive performance across development, (b) what are the associated compensational mechanisms and (c) are these compensational mechanisms plastic across the lifespan. Methods. To answer these questions, we …suggest to integrate behavioural and neuroimaging methods and present specific methods and their advantages and disadvantages. Results. We will illustrate the relevance of this integration by presenting data using ERPs and (s)LORETA to study compensational processes across the lifespan in a higher order cognitive function, i.e., delayed intentional behaviour. A higher activation in old adults or adolescents in successful trials compared to young adults is considered compensatory as specialized cortical regions are selectively recruited in response to task demands. Conclusions. Findings show that whereas the performance outcome might be the same across age groups, underlying processes and activations might be fundamentally different. We conclude with a discussion about specific implications of this integrative approach when studying the adaptive potentials and limits of human cognition. Show more

Keywords: development, aging, cognitive neuroscience, successful, performance

DOI: 10.3233/RNN-2009-0513

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 421-433, 2009

Authors: Noack, Hannes | Lövdén, Martin | Schmiedek, Florian | Lindenberger, Ulman

Article Type: Research Article

Abstract: Interventions enabling aging individuals to fulfill their plastic potential promise to postpone, attenuate, or even reverse the adverse effects of senescent brain changes on cognitive abilities and everyday competence in old age. Based on an overview of the concept of plasticity in lifespan development, we selectively review evidence from cognitive intervention studies and conclude that most of them have failed to observe generalizable performance improvements, as documented by the small size and scope of positive transfer …to untrained tasks. We further note that generally accepted criteria for defining transfer distance are lacking, rendering the relevant evidence difficult to interpret. Hence, we propose a taxonomy of transfer distance based on the structure of human intellectual abilities. Show more

DOI: 10.3233/RNN-2009-0496

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 435-453, 2009

Authors: Zelinski, Elizabeth M.

Article Type: Research Article

Abstract: Purpose: This article reviews the literature on far transfer effects in training of older adults. Methods: Adapting a taxonomy of transfer developed by Barnett and Ceci (2002), to rehabilitation or enhancement of existing cognitive skills; results of studies assessing transfer effects from training of memory, reasoning, UFOV, dual task performance, and complex training are classified. Results: Comparisons of the transfer outcomes of both strategy training and extended practice approaches suggest that far …transfer has been observed. Conclusions: Outcomes for strategy studies training memory have had less success than extended practice studies in obtaining far transfer. Reasons for this are discussed, as are suggestions for improved assessment of transfer outcomes. Show more

DOI: 10.3233/RNN-2009-0495

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 455-471, 2009

Authors: van Paasschen, Jorien | Clare, Linda | Woods, Robert T. | Linden, David E.J.

Article Type: Research Article

Abstract: Purpose: This review considers the application of functional magnetic resonance imaging (fMRI) to identify treatment effects and brain plasticity in cognition-focused interventions aimed at people with Alzheimer's disease (AD). At present there is little evidence available that bears directly on this question. Associative memory function is affected in the early stages of AD and also deteriorates disproportionately in comparison to other types of memory in healthy ageing. Methods: We review paradigms from the …literature on face-name learning in fMRI in three groups (AD, mild cognitive impairment, and healthy ageing) with the aim of developing a paradigm to measure treatment effects and functional plasticity following cognitive intervention. Results: Previous studies have commonly selected participants with high levels of education, and have generally used challenging tasks, with considerable variations in level of task performance across studies. The findings of the review indicate that there is a need a simple face-name learning paradigm that can be used with people with AD, and which can be applied either as a single assessment tool to compare various subject groups or as an outcome tool to assess functional changes following a period of cognitive intervention. Conclusions: We make recommendations for such a paradigm and discuss pilot data showing the successful application of our paradigm in an individual with MCI. Show more

Keywords: Neural plasticity, mild cognitive impairment, dementia, associative memory, fMRI, treatment outcome

DOI: 10.3233/RNN-2009-0494

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 473-491, 2009

Authors: Burgess, Paul W. | Alderman, Nick | Volle, Emmanuelle | Benoit, Roland G. | Gilbert, Sam J.

Article Type: Research Article

Abstract: Purpose: Mesulam's (1986) mystery is that some patients with frontal lobe damage may show no cognitive impairment according to traditional office-based assessment procedures, yet nevertheless show marked cognitive handicap in everyday life. Mesulam suggested that "the office setting may introduce sufficient external structure to suppress some of these behavioral tendencies" (p. 322). We ask if it is indeed the office setting that is the problem, or whether it is that traditional assessments do not measure the …full range of cognitive functions supported by prefrontal cortex. Method: Neuropsychological case series study and review. Results: Traditional methods for assessing cognitive deficits following frontal lobe damage typically do not measure the full range of deficits that can occur. In particular, rostral prefrontal cortex supports functions which are not routinely assessed yet are crucial to competent everyday life performance. These include meta-memory functions (e.g. context and source memory), complex behavioural co-ordination (e.g. prospective memory and multitasking), and mentalizing. Conclusions: New clinical assessment procedures are required urgently. These could be based, in principle, both on recent experimental findings from cognitive neuroscience, and observation of behaviour outside office settings. These procedures could then be administered in an office setting. Show more

DOI: 10.3233/RNN-2009-0511

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 493-506, 2009

Authors: Zehnder, Franzisca | Martin, Mike | Altgassen, Mareike | Clare, Linda

Article Type: Research Article

Abstract: In most studies on plasticity using behavioural data, cognitive plasticity has been studied in the context of short-term interventions such as memory training. In order to systematically review the literature on memory training and summarize its effects for old healthy people and people with mild cognitive impairment on multiple functional domains, we conducted a meta-analysis of all published randomized controlled trials (RCT) between 1970 and 2007. Overall, 24 studies examining memory training effects in healthy and …in mildly cognitively impaired old adults were identified and included in the analysis. Only memory trainings (e.g. memory skills training, imagery, method of loci) with cognitive outcome measures, duration of intervention with up to one year with at least a baseline and a post-intervention assessment reported, were included. Results demonstrate significant training effects for paired associate learning and immediate and delayed recall in healthy old adults and for immediate recall in mildly cognitively impaired old adults. However, training effects were no larger than those found for active control conditions. Our results suggest that evidence on the effectiveness and specificity of training interventions is scarce. We discuss limitations of existing knowledge about the efficacy of memory training interventions and implications for future research to improve knowledge regarding effective cognitive interventions. Show more

Keywords: Plasticity, memory training, meta-analysis, old age, mild cognitive impairment

DOI: 10.3233/RNN-2009-0491

Citation: Restorative Neurology and Neuroscience, vol. 27, no. 5, pp. 507-520, 2009