Handbook of gerontology research methods leigh riby, routledge, 2017 scan

Designed for both students and researchers interested in the psychology of aging, but also highly relevant for students or researchers in related fields such as health psychology and soc

HANDBOOK OF GERONTOLOGY

RESEARCH METHODS

The Handbook of Gerontology Research Methods offers a clear understanding of the

most important research challenges and issues in the burgeoning field of the chology of aging As people in developed countries live longer, so a range of research methods has evolved that allows a more nuanced understanding of how we develop psychologically and neurologically Allied to this is an increasing concern with the idea of well-being, a concept that places cognitive performance and development within a more socially grounded context

With contributions from a range of top international scholars, the book addresses both typical and atypical aging, highlighting key areas such as physical and cognitive exercise, nutrition, stress, diabetes and issues related to death, dying and bereave-ment Successful aging is emphasised throughout the text Each chapter concludes with a series of practical tips on how to undertake successful research in this area This unique collection is the first book to provide both a concise overview of the major themes, findings and current controversies in this growing field, as well as an understanding of the practical issues when researching older adults that may impact

on research outcomes, intervention, policy and future directions

Designed for both students and researchers interested in the psychology of aging, but also highly relevant for students or researchers in related fields such as health

psychology and social care, the Handbook of Gerontology Research Methods is essential

reading for anyone wishing to understand more about the psychology of aging

Dr Leigh Riby is Associate Professor of Neuropsychology at Northumbria

Uni-versity, United Kingdom

Research Methods in Developmental Psychology is a series of edited books focusing upon research challenges for conducting research in developmental psychology Ideally suited to both students coming to this area for the first time and more expe-rienced researchers each volume provides an invaluable overview of research in this growing field, and how it can inform both education and interventions Volumes include research challenges in neurodevelopmental disorders, child development and gerontology.

Published titles:

Neurodevelopmental Disorders: Research Challenges and Solutions

Edited by Jo Van Herwegen and Deborah Riby

Practical Research with Children

Edited by Jess Prior, Jo Van Herwegen

A Handbook Series

HANDBOOK OF

GERONTOLOGY

RESEARCH METHODS

Understanding successful aging

Edited by Leigh Riby

by Routledge

2 Park Square, Milton Park, Abingdon, Oxon OX14 4RN

and by Routledge

711 Third Avenue, New York, NY 10017

Routledge is an imprint of the Taylor & Francis Group, an informa business

© 2017 selection and editorial matter, Leigh Riby; individual chapters, the contributors

The right of the editor to be identified as the author of the editorial material, and of the authors for their individual chapters, has been asserted

in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988

All rights reserved No part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers

Trademark notice : Product or corporate names may be trademarks or

registered trademarks, and are used only for identification and explanation without intent to infringe

British Library Cataloguing in Publication Data

A catalogue record for this book is available from the British Library

Library of Congress Cataloging-in-Publication Data

Names: Riby, Leigh, editor.

Title: Handbook of gerontology research methods : understanding successful ageing / edited by Leigh Riby.

Description: Abingdon, Oxon ; New York, NY : Routledge, 2017.

Identifiers: LCCN 2016011099 (print) | LCCN 2016017407 (ebook) | ISBN 9781138779037 (hardback : alk paper) | ISBN 9781138779068 (pbk. : alk paper) | ISBN 9781315771533 (Ebook)

Subjects: LCSH: Gerontology—Research—Methodology | Aging—

Acknowledgements viii Editor contact details ix

Biographical profile of contributors xi

SECTION I

1 Understanding successful ageing, key challenges

Riby, Leigh, Greer, Joanna, Martinon, Léa M

and Reay, Jonathon L

SECTION II

Lifestyle factors and psychological functioning 15

2 Physical and cognitive exercise in ageing 17

Rabipour, Sheida, Miller, Delyana, Taler, Vanessa, Messier,

Claude and Davidson, Patrick

3 Nutrition, health and the ageing process 43

Peters, Riccarda, White, David and Scholey, Andrew

4 Stress, coping and resilience in an ageing population 60

Phillips, Anna C and Vitlic, Ana

CONTENTS

5 The dual continua model of mental health and illness:

theory, findings, and applications in psychogerontology 79

Westerhof, Gerben

6 Successful ageing in the workplace:

a resources-oriented intervention perspective 95

Stamov Roßnagel, Christian and Jeske, Debora

7 Ageing and retirement behaviour 118

Shultz, Kenneth and Fisher, Gwenith

SECTION III

Less successful ageing 137

8 The frontal ageing hypothesis: evidence from

normal ageing and dementia 139

MacPherson, Sarah and Cox, Simon

9 Examining cognitive function in type 2 diabetes:

the importance of an inclusive research approach 159

Jones, Nicola, Greer, Joanna, Riby, Leigh and Smith, Michael

10 Alzheimer’s disease: interaction of lifestyle factors

and traumatic head injury 180

Scholes-Balog, Kirsty, Albrecht, Matthew and Foster, Jonathan

SECTION IV

Novel interventions for dementia 203

11 The effect of music therapy for people with dementia 205

Vink, Annemieke and van Bruggen-Rufi, Monique

12 Poetry as a means of (re)creating satisfying levels of

personhood and social integration for people diagnosed

with dementia: method, discussion and outcomes 223

Petrescu, Ioana

SECTION V

End of life 233

13 Death, dying and bereavement in old age:

working towards a ‘good death’ for elderly individuals 235

Wylie, Belinda and Smith, Michael

Index 249

To my Gran Margaret (1923–2015) the perfect example of successful ageing Thank you to my parents and daughters Jessica and Amelia Riby

ACKNOWLEDGEMENTS

Leigh Riby earned a BSc (Hons) in Psychology from the University of Lincolnshire

He achieved a PhD in Experimental Psychology in the area of cognitive ageing and frontal lobe deficits at the Department of Experimental Psychology, Bristol University During post-doctoral work at the University of Stirling Dr Riby gained expertise in multi-modal brain imaging (EEG and fMRI) More recently,

Dr Riby has published a catalogue of research papers on the topic of glycaemic modulation of cognitive processes, memory and mind wandering using behavioural and neuroimaging techniques in younger adults, older adults and patient groups

Dr Riby is currently an Associate Professor Neuropsychology at Northumbria with teaching interests in ageing, neuropsychology and the creative mind

BIOGRAPHICAL PROFILE

OF EDITOR

Matthew Albrecht holds a PhD in Pharmacology from the University of Western

Australia He is currently an Australian National Health and Medical Research Council Early Career Research Fellow situated at the Maryland Psychiatric Research Center, University of Maryland and at the School of Public Health at Curtin University His is currently working on electrophysiological markers of reward processing in schizophrenia and translational animal models of psychosis

Simon Cox carried out his PhD at the University of Edinburgh (UK), examining

relationships between cortisol, brain structure and cognitive ability in older age He

is currently an MRC-funded Research Associate in Brain Imaging and Cognitive Ageing at the Centre for Cognitive Ageing and Cognitive Epidemiology, University

of Edinburgh (UK) His interests include the potential determinants of structural brain changes in older age and their cognitive correlates, which he investigates primarily in the Lothian Birth Cohort 1936

Patrick Davidson (PhD) is an Associate Professor in the School of Psychology

at the University of Ottawa, where he is also a Scientist at the Bruyère Research Institute and an Associate Member of the Brain-Mind Research Institute and the Canadian Partnership for Stroke Recovery He works on the cognitive neuroscience

of human memory, executive functions and emotion, including in normal aging and in brain injuries, disorders and diseases

Gwenith Fisher earned her PhD in Industrial/Organizational Psychology from

Bowling Green State University She is currently Assistant Professor of Industrial/Organizational Psychology and Director of Training in Occupational Health Psychology at Colorado State University Her research examines occupational

BIOGRAPHICAL PROFILE

OF CONTRIBUTORS

health, retirement and well-being among older workers and work/life issues Prior

to joining the faculty at CSU, Gwen spent twelve years working at the Institute for Social Research (ISR) Survey Research Center at the University of Michigan

Jonathan Foster holds a doctorate in behavioural neuroscience from the University

of Oxford, subsequent to which he completed clinical and experimental training

in neuropsychology at the Roman Institute in Toronto He has been awarded university chairs in the United Kingdom and Australia He is currently a Consultant Neuropsychologist (Health Department of Western Australia and Private Practice) and a Clinical Professor at Curtin University and the University of Western Australia His research focuses on the neurological basis of cognition, including lifespan developmental perspectives

Joanna Greer is a Senior Research Assistant at Northumbria University (UK)

working on a diverse range of projects including behavioural and neuropsychological processing in healthy children and adults, and clinical research studying cognitive and linguistic deficits in aphasic stroke patients She is currently in the final year

of her PhD, investigating executive dysfunction in older adults with Williams syndrome

Debora Jeske holds a PhD in Industrial-Organizational Psychology from Northern

Illinois University (USA) She is a lecturer in Human Resource Management in the Business School at Edinburgh Napier University (UK) Her research interests include studying different approaches of training and development, virtual working and the use of social media for personal and work purposes

Nicola Jones is Lecturer at Liverpool Hope University She completed her PhD at

Northumbria University investigating the impact of glucoregulatory efficiency on neurocognitive mechanisms in older adults She currently works as a post-doctoral fellow at Liverpool Hope University Her research interests include investigating the impact of glucoregulation on memory processing and how these processes are represented behaviourally and at a neural level in both typical and atypical populations

Sarah MacPherson’s PhD work was the first to propose the dorsolateral prefrontal

theory of cognitive aging Since then her research interests have focused on cognitive and neuropsychological investigations of memory, executive abilities and social functioning in healthy and pathological ageing and damaged brains She is currently a Senior Lecturer in Human Cognitive Neuroscience at University of Edinburgh (UK)

Léa M Martinon holds a Masters in cognitive psychology from Université de

Bourgogne She is currently doing her PhD in the Faculty of Health and Life Sciences in Northumbria University in Newcastle-upon-Tyne Her research focuses on aging and ubiquitous phenomenon like mind-wandering

Claude Messier, during his Masters and PhD thesis at McGill University, discovered

that ingestion or injection of glucose could improve memory He went on to study the effect in humans and discovered that the effect was more prominent in people with impaired glucose tolerance In 1996, he wrote a review that explained why and how diabetes would be a risk factor for Alzheimer’s disease and proposed several

of the hypotheses that have proven useful Claude Messier also discovered that the expression of the main blood to brain glucose transporter (GLUT1) increases when neurons are being activated by new learning

Delyana Miller obtained her PhD in Clinical Psychology from the University of

Ottawa, where she researched the cognitive factors that predict successful interaction/communication with interactive voice response technology in older adults She also completed a methodological review of the literature that measures the impact of physical exercise on cognitive aging Dr Miller completed her doctoral residency

in clinical neuropsychology at the Ottawa Hospital and her research evaluated the effectiveness of computer-based cognitive neurorehabilitation interventions in adults She is currently working at her private practice and in the Children’s Hospital

of Eastern Ontario as a clinical psychologist and neuropsychologist Her research interests include cognitive function and interventions geared towards preserving cognitive function later in life

Riccarda Peters holds a MSc in Behavioural and Cognitive Neurosciences from the

University of Groningen, the Netherlands She is currently enrolled as a PhD candidate

at Swinburne University, Australia, in the Centre for Human Psychopharmacology, where she is exploring brain changes associated with advancing age and nutritional interventions

Ioana Petrescu is a widely published academic and poet, who teaches Creative

Writing at the University of South Australia She is the author of three poetry collections, more than a hundred poems published in literary and academic journals, editor of many books of poetry, and has successfully supervised Honours, Masters and PhD theses in Creative Writing Her interest in the effects of poetry on Alzheimer’s sufferers began in the family and over time expanded into her research and community engagement

Anna C Phillips is an internationally renowned researcher and Health Psychologist

working in Psychoneuroimmunology and Psychophysiology She has conducted award-winning work on stress and vaccination response across the life course

Dr Phillips was appointed as a research associate during her PhD at the University

of Birmingham, and undertook post-doctoral research for one year following her PhD with Professor Douglas Carroll She then went on to win a prestigious five-year RCUK Roberts Fellowship, which is a fast-track fellowship that segues into a lectureship following its completion On completion of the fellowship in 2011 she was promoted to Senior Research Fellow, and then again to Reader in Behavioural

Medicine in 2012 She has received three Early Career Awards for research: the Herbert Weiner Early Career Award 2010 from the American Psychosomatic Society – one of only two UK scientists to ever win this award, which is made in recognition of importance and sophistication of research for this career stage; the Neal Miller Early Career Award 2010 from the Academy of Behavioral Medicine Research – a very prestigious award for research; and the Stress and Anxiety Research Society Early Career award in 2014 In 2011 Dr Phillips became the inaugural winner of the award for Outstanding Contribution to Research from the British Psychological Society Division of Health Psychology

Sheida Rabipour is completing her PhD in Psychology at the University of Ottawa,

following BSc and MSc in Neuroscience at McGill University Her research centers

on cognitive training and psychological well-being She also works to raise awareness

on brain health through public blogs and workshops

Jonathon Reay holds a BSc in Psychology and a PhD in psychopharmacology from

Northumbria University He is currently head of Psychology at Teesside University His research focuses on exploring the efficacy of nutritional interventions for psychological health

Kirsty Scholes-Balog is a Postdoctoral Research Fellow within the Learning Sciences Institute, Australian Catholic University Her research focuses on longitudinal predictors and consequences of health and behaviour of young people Her main research interests include substance use, mental health and problem behaviors

Andrew Scholey holds a PhD in cognitive neuroscience from the Brain and Behaviour Research Centre, Open University He is currently director of the Centre for Human Psychopharmacology, Swinburne University, Melbourne, Australia He studies many aspects of human psychopharmacology including the influence of dietary bioactives His current research focuses on understanding the mechanisms of cognitive enhancement in both cognitively intact and clinical populations

Kenneth Shultz earned his PhD in Industrial/Organizational Psychology from Wayne State University in Detroit, Michigan He is currently a Professor

of Industrial/Organizational Psychology and Interim Director of the Center on Aging at California State University, San Bernardino His research focuses on aging workforce issues, including mid- and late career issues, bridge employment and retirement Previously he worked for the City of Los Angeles as a Personnel Research Analyst and has consulted with a wide variety of companies

Michael Smith holds a PhD in Psychology from the University of Western Australia He is currently Senior Lecturer in Psychobiology and Health Psychology

at Northumbria University (UK) and Adjunct Senior Lecturer in the Medical School at the University of Western Australia

Christian Stamov Roßnagel holds a PhD in Psychology He is currently a professor

in organisational behaviour at Jacobs University Bremen (Germany) His research focuses on generational differences in work-related learning competency, resource-oriented interventions to increase learning motivation and personalised e-learning

Vanessa Taler holds an MA in Linguistics from McGill University and a PhD in

Biomedical Sciences from Université de Montréal She is currently an Associate Professor in the School of Psychology at University of Ottawa and a Scientist at the Bruyère Research Institute in Ottawa, Canada Her research focuses on language and cognitive processing in people with mild cognitive impairment and Alzheimer’s disease

Monique van Bruggen-Rufi holds a Master’s degree in music therapy and was trained

as neurological music therapist-fellow She works as a lecturer in music therapy and guitar skills at the music therapy bachelor program offered by ArtEZ Conservatory School of Music in Enschede, the Netherlands Furthermore, she lectures for the Master

of Arts Therapies program at Zuyd University in Heerlen, the Netherlands She is a regular guest speaker at (national and international) universities and conferences She is currently working on her PhD-research on music therapy with Huntington’s Disease

at the Neurology Department of the Leiden University Medical Center in Leiden, the Netherlands She also works as a researcher at Atlant Care Group in Apeldoorn, the Netherlands, a long-term care facility specialized in Huntington’s Disease Her main areas of expertise are neurodegenerative diseases such as Huntington, Parkinson and dementia Before Monique committed herself completely to music she worked as an operation room nurse and a physician’s assistant

Annemieke Vink has been trained as a psychologist and in Neurological Music Therapy She carried out a PhD to study the effects of music therapy to reduce agitation in elderly people with dementia at the University of Groningen (the Netherlands) She works as

a lecturer in theory of music therapy at the bachelor music therapy program offered

by ArtEZ Conservatory School of Music in Enschede, the Netherlands Furthermore, she lectures for the Master of Music and Master of Music Therapy at ArtEZ and is also a core team member and lecturer on the Master of Arts Therapies Course (Zuyd University) She works as a researcher at ArtEZ (research center for music therapy) and KenVaK (research center for the art therapies) Her main areas of expertise are the effect

of music therapy on people with dementia and music psychology Annemieke Vink has presented at various national and international congresses on the topic of music therapy and effects of music therapy for elderly people specifically and has written various publications about music therapy, music psychology and the effects of music therapy on people with dementia and related diseases

Ana Vitlic was a European Commission FP7 Marie Curie Innovative Training

Network PhD student with Dr Anna Phillips at the University of Birmingham School of Sport, Exercise and Rehabilitation Sciences until she graduated in 2014 Her research area was stress and immunity in ageing She now works as a research scientist for a small assay development company in the UK

Gerben Westerhof (PhD, 1994) is adjunct professor of Narrative Psychology at the

University of Twente, Enschede, the Netherlands, and director of the Story Lab at this university His research focuses on well-being and personal meaning in aging

He is also interested in the use of narrative and life review methods to promote well-being and meaning in life

David White holds a PhD in Cognitive Neuroscience from Swinburne University,

Melbourne, Australia He is currently a Post-doctoral Research Fellow with the Centre for Human Psychopharmacology at Swinburne, where his primary research focus uses neuroimaging methods to assess the neurocognitive outcomes from a range of nutritional and psychopharmacological interventions

Belinda Wylie holds a degree in Social Sciences She has previously worked as

a Cancer Services Coordinator at Macmillan Cancer Support, and lectures on the topic of bereavement to MSc Health Psychology students at Northumbria University (UK)

SECTION I

Introduction

During the previous two decades, academics, health care professionals, and members

of the general public have been relentless with their desire to further explore and understand the multidimensional relationship between ageing, physical health, and psychological wellbeing In particular, there has been substantial interest in the role that individual differences, lifestyle choices, and the environment play in typical and atypical ageing; exploring their impact on disease aetiology, disease progression, treatment plans, and more recently, disease prevention is essential This increased interest and scientific enquiry is largely due to the estimated additional 400 million adults who will be 80 years and over by the year 2050 (World Health Organization, 2014) Moreover, the associated exponential rise in age-related health care problems

is coupled with a current lack of suitable interventions and understanding As a result, there is now a race to uncover and understand the secrets of ‘successful age-ing’ to slow the onset and progression of the inevitable age-related health problems Although difficult to define, as we will explore below and throughout the text, successful ageing is a key contemporary concept that arouses much debate; as living longer should not be assumed as synonymous with good news, if one’s prolonged life results in more years of disease and suffering Regardless, with life expectancy increasing, successful ageing is extremely important and we need to treat the ageing population in a positive light, to be celebrated and seen as active contributors to society (see Stephens & Flick, 2010)

Defining successful ageing is in itself problematic; however, let’s first consider ing and Dieppe (2005) who state that any definition “. . . needs to include elements that matter to elderly people” (p 1548) This certainly needs to be kept in mind, as

Bowl-we soon become lost in lab-based experimental data and theoretical positions with no obvious link nor application to the everyday lives and wellbeing of elderly individu-als Indeed, it could be argued that there is often a misalignment between academic researchers and older adults’ definitions of successful ageing When successful ageing

1

UNDERSTANDING SUCCESSFUL

AGEING, KEY CHALLENGES AND

RESEARCH METHODS

Riby, Leigh, Greer, Joanna, Martinon,

Léa M and Reay, Jonathon L

is rated by older adults themselves, 50.3% of them seemed to have aged successfully whereas only 18.8% of them did when using research criteria (Strawbridge, Wallha-gen, & Cohen, 2002) Often, all components rated as important by the elderly are not always considered in their entirety by research workers (i.e. physical, functional, psy-chological, and social health; Phelan, Anderson, Lacroix, & Larson, 2004) We know, from a plethora of research, that illness, disability, and distress occur concomitantly with the ageing process; however, we know far less about the factors that contribute to successful independent living and quality of life during the ageing process in the face

of these challenges Rowe and Kahn (1987) were one of the first to introduce the idea

of successful ageing and their model will provide the groundwork According to their model there are three inter-related factors that make positive outcomes more likely as

we age (see Fig 1.1 ) It is worthwhile keeping in mind that older adults are resilient even in the presence of impairment in one of these three domains; compensation drawing on strengths and stability is key to growing older successfully

Minimal impact of disease and disability The physical changes that occur during

ageing are well documented (e.g reduced arterial elasticity, reduced immune, lung, kidney, and the endocrine function, and more observable changes to the muscu-loskeletal system; for a review, see Lowry, Vallejo, & Studenski, 2012) Even in the absence of disease these changes impact upon normal everyday living and quality

of life; however, we know that disease processes amplify these difficulties, especially

in the presence of debilitating diseases such as Alzheimer’s disease, arthritis,

osteo-porosis, heart disease, and diabetes In this regard, the active life expectancy (years of

independent living) has proven to be a useful conceptualisation of ageing well Undeniably, improvements in healthcare provisions, medical advances, and novel strategies for compensation have helped ameliorate the negative impact of ageing

and disease, allowing older adults to be active members of society for longer

In the present text we focus on psychological function, brain, and behaviour and use dementia as an example In a meta-analytic review, Prince et  al (2013) report a worldwide estimate of 36 million people living with dementia in 2010 and

Minimal Disease/

Disability

Superior Cognitive and Physical Function

Social Engagement

FIGURE 1.1 Factors contributing to successful ageing Based on Rowe and Kahn (1987)

a worrying anticipated increase, to 66 million in 2030 and 115 million in 2050 Neuro-cognitive deficits are central to the disorder with declines in the early stages

of the disease seen in the psychological constructs of episodic memory, working memory, executive function, and perceptual speed (see for example Bäckman, Jones, Berger, Laukka, & Small, 2005) Therefore, expectancies of an active life become critical Indeed, the uniqueness of the cognitive profile compared to ‘normal’ ageing and mild cognitive impairment (Riby et al., 2009) can impact extensively on the everyday activities and ability to live independent lives Therefore, the notion of an active life expectancy becomes critical Indeed research has identified modifiable risk factors for dementia (e.g years of education, Brayne et  al., 2010; nutritional imbalance such as low vitamin D concentrations, Balion et al., 2012, Brown, Riby, & Reay, 2009, Reay, Smith, & Riby, 2013; and physical exercise, Lindsay et al., 2002) and has demonstrated the effectiveness of compensation strategies (e.g external memory aids, Fried-Oken et al., 2012; aerobic and resistance exercise, Brown et al., 2015) for managing disease symptoms and extending active life (for a recent review, see Baumgart et al., 2015) Thus, all of these possibilities of compensations imply

a strong individual variability in how people deal with ageing or diseases Recent findings indicate that this inter-individual variability could be explained by differ-ent degrees of cognitive reserve, meaning that brain differences could lower or offset the effect of ageing (Ducharme-Laliberté, Boller, & Belleville, 2015)

Superior cognitive and physical function Relatively stable mental and physical

func-tion in addifunc-tion to being free from disease is an important considerafunc-tion for seniors seeking quality of life in later years Uncovering the mechanisms that might result

in stability or at least minimal decline in physical and cognitive function is mount in a successful ageing agenda The obvious route is to promote research activities aimed at examining predictors (e.g diet, exercise, lack of smoking) of successful ageing and also targeting these to healthy behaviour in midlife (Britton, Shipley, Singh-Manoux, & Marmot, 2008) For example, epidemiological studies support the notion that regular exercise in midlife can reduce the risk of cogni-tive decline and dementia in older adults (Forbes et al., 2015a, 2015b) Forbes et al (2015a, 2015b) in their recent reviews outline the plausible biological basis of exer-cise on cognitive outcomes in middle age; for example, exercise might promote reductions in systemic inflammation, promote efficient brain insulin function, and may reduce oxidative stress A final component to consider in this second domain

para-of successful ageing is that there is a reciprocal relationship between physical tion and psychological performance with the former having been shown to have clear benefits to the latter Weuve et al (2004) investigated the long-term effects of physical exercise on cognitive function and demonstrated the beneficial effects of not only vigorous exercise but even lighter forms of physical activity (i.e walking) The mechanisms driving this relationship (e.g improved vascular health and more direct effects on neurochemistry) will receive coverage throughout the text but the find-ings over performance benefits even for light exercise is promising and would mean only small adaption would be needed in the lives of the older adults Interestingly from a cognitive perspective, physical exercise has been demonstrated to improve

func-those numerous psychological constructs known to be vulnerable to ageing (e.g verbal episodic memory; executive function; e.g Colcombe & Kramer, 2003)

Social engagement The final component of successful ageing that provides

com-pensation for the debilitating effects of disease and the physical and psychological changes that occur in normal ageing is the presence of a strong social support net-work In a recent report from the Office of National Statistics (2013) 46% of the elderly over the age of 80 reported a feeling of loneliness some of the time or often This statistic is particularly worrying given the association between loneliness and reported difficulties in everyday task performance, emotional and physical wellbe-ing, and quality of life (Pinquart & Sörensen, 2000) Growing older brings about a number of significant life changes that are associated with being alone such as loss

of partner and restrictions caused by disability but an important consideration is that being alone predicts health concerns (e.g depression, cardiovascular impacts) and difficulties on everyday activities Interventions that target social isolation and loneliness are welcomed by policy makers if the end result is improvements in wellbeing and a sense of social belonging in the community (Stanley et al., 2010)

A large-scale study on social support is particularly relevant here Matthews (1984)

in an early paper on the topic rightly points out that the complexity of social port makes it extremely difficult to uncover how detrimental effects of ageing can

sup-be minimised Difficulties in definitions are here problematic with loneliness and social isolations being often used interchangeably (Stanley et al., 2010) Social iso-lation does not necessarily lead to loneliness and other concerns include the lack

of older adults’ perspective on loneliness that is often neglected by researchers (see influential paper by Stanley et al., 2010) Similarly what seems to be disregarded in the research is the fact that both receiving and giving social support has a positive impact on health, quality of life (e.g life satisfaction), and psychological wellbeing Kim, Hisata, Kai, and Lee (2000) make this precise point with reciprocal exchange being beneficial, whereas an unequal exchange of social support often leads to dis-tress Even social media has proven beneficial with this being ideal in keeping in touch with loved ones and family members and maintaining their sense of belong-ing in a community and good mental health (Senior Care Corner, 2015) Indeed,

an innovative cross-cultural computer training study has stressed digital inclusion

to promote active ageing and the reduction of social isolation (AGES 2.0, 2015)

Organisation of the book

This book brings together the work of prominent researchers within the field of ontology, taking a successful ageing approach already outlined We have specifically selected chapters focusing on some of the key challenges facing the gerontologist and ‘hot topics’ in the field As the title of the volume suggests, the collection of chapters particularly focus on a number of practical issues when researching older adults, which may impact on research outcomes, interventions, policy, and future directions in the area Practical research tips will be considered in each chapter It is worthwhile highlighting that successful ageing will be a key theme of all chapters

ger-and work will cover both ‘normal’ ger-and pathological ageing As a result, the reader will acquire specialist knowledge about impairment and disease processes that might accompany the ageing process as well as an understanding that decline is not an inevitable consequence of growing old

In Chapter 2, Rabipour and colleagues outline the increasingly popular tion of physical exercise as a route to stabilising cognitive and mental performance The authors rightly point out that there are significant methodological limitations that make it difficult to argue for a direct link between physical interventions and cognitive enhancement Observational studies are of course problematic as it is difficult to ascertain the cause and effect relationship Furthermore, other factors that we have already identified as being critical to successful ageing such as social interaction may make up a more complex model when explaining the link between increased physical exercise and optimal psychological function Besides considering methodological limitations the authors outline key studies suggesting clear impacts

interven-on brain systems and processes For example, both structural and functiinterven-onal imaging techniques have proven fruitful in revealing anatomical and connectivity changes in the brain At a cellular level, vascular and potential effects on growth and self-repair

of neurons are outlined Turning to cognitive exercise the authors discuss the types

of activities that might constitute ‘exercise’ and may lead to positive outcomes (e.g formal schooling, crossword puzzles, meditation) Interestingly, combined physical and cognitive exercise is a promising but understudied research endeavour

In Chapter 3 , Peters and colleagues discuss the role of nutrition on the tive ageing process After outlining some of the main pharmacological interventions available for the treatment of older adults and patients with dementia the authors outline dietary compounds that have the potential to target and prevent cognitive decline Following a Mediterranean diet has received much interest in the popular press and here the authors critically evaluate this dietary pattern Multicentre studies have been informative and point to lower risk of death from cardiovascular disease, cancers, obesity, and particularly relevant here age-related brain impairment (e.g Parkinson’s and Alzheimer’s disease) Coverage of Omega-3 fatty acids and brain function follows with review, an examination of possible mechanisms leading to facilitation and methodological challenges Identifying the populations that can ben-efit is critical, as not all older adults can profit, with later progression of Alzheimer’s disease highlighted as an example where neural substrates has deteriorated such that response to dietary intervention is no longer possible An insightful final section on general considerations for nutritional interventions closes the chapter, with inclusion

cogni-of how traditional behavioural methods can be used alongside imaging techniques to explore nutrition and the ageing process

In Chapter 4 , Phillips and Vitlic outline elegantly the impact of stress on the immune system and consider implications for reliance in old age Indeed, once the putative mechanisms linking immunological and endocrinological changes to resil-ience in old age have been discussed, the authors evaluate older caregivers’ difficulties (focusing on older caregivers of dementia patients) and their psychological wellbe-ing Chronic stress in older individuals has major impacts on immunity with older

dementia carers’ wound healing reported to be slower and responsiveness to vaccines

to be impaired Telomere length, which has recently been considered a clear marker

of disease and the ageing process, is evaluated (for review see Mather, Jorm, Parslow, & Christensen, 2011) For example, telomere length has been reported to be shorter

in older caregivers of dementia patients, and for that reason a valuable marker of environmentally induced differences in rates of ageing (Damjanovic et al., 2007) Social support is once more considered as an important component of successful ageing being linked to psychological stress and coping Immune function is known

to be moderated by loneliness and social network size across the lifespan Further

‘healthy’ behaviours (e.g exercise, balanced diet, adequate sleep) are evaluated for their direct impact on both perceived stress and immune system functioning Get-ting the balance right is of course very important as stress during some activities and situations can be beneficial to health

In Chapter 5 , Gerben Westerhof examines mental health and illness in an older population The author begins by emphasising the multidimensional nature of mental health and illness to include different aspects of psychological and social functioning The dual continua model is proposed before evaluating empirical work in support of this model According to this model the presence or absence of poor mental health and illness represents two distinct but related dimensions (factor analyses suggest two rather than one dimension) Importantly, the suggested model appears to provide a good fit to the ageing data, including both losses and gains as we grow older and will prove to be influential in future experimental work in this area The authors evaluate interventions that promote positive mental health across the lifespan Reminiscence and life reviews are seen as extremely effective Encouraging

an individual to think back and reflect on life events and adding meaningfulness to the individual is seen as a valuable tool to minimise mental health problems as we grow older Research including comprehensive meta-analyses has indicated positive outcomes such as reduced depressive symptoms Reminiscence activities are diverse and may include autobiographical writing, family genealogy, and blogging

In Chapter 6 , Stamov Roßnagel and Jeske evaluate applied research in the place and propose that such a setting provides the ideal context for studying successful ageing The resource orientation approach is emphasised throughout the chapter with strategies and compensation in the management of limited resources as we grow older

work-a primwork-ary concern Since older work-adults work-are beginning to outnumber younger collework-agues

in the workplace and there is an increasing trend for working beyond the traditional retirement age, strategies for scaffolding performance is essential in the constantly changing work environment Gains and losses are the focus with setting new goals and acquiring new skills beneficial Losses are associated with the known biological and cognitive decline with strategies and the employment of those abilities known to be stable as we grow older important Methodological implications of resources-oriented research in the work settings and survey-based studies are discussed with motivation used as an example Age differences in motivation at work and how the consideration

of affective processes is critical in the study are discussed The chapter concludes with

resource-orientated interventions, which are designed to help an individual become more aware and efficiently use existing resources as well as acquiring new resources to aid task performance Importantly the contributors highlight that work on motivation and ageing is in good shape but suggest theories tend to emphasise cognitive compo-nents at the expense of affect Overall the resource approach outlined will provide the groundwork for subsequent work in the area, helping researchers, practitioners, and managers in their endeavours to support successful ageing

Shultz and Fisher in Chapter 7 introduce and discuss retirement and ate methods that may be employed to evaluate this difficult to define concept By examining how retirement has changed in recent decades the authors are able to effectively explore this important life transition The historical account is followed

appropri-by an evaluation of why a senior may wish to continue work In addition to nomic reasons, maintaining a sense of identity or just a great way to continue to receive social support are outlined Much like successful ageing itself, retirement

eco-is difficult to define but the researchers stress the temporal nature of the process with longitudinal research encouraged (especially given the easy access to existing datasets) The processes may include retirement planning, decision making, and the final stages involved in the adjustments during the transition into retirement Individual differences are considered, for instance, women (particularly divorced

or widowed) are more likely to have interrupted careers due to childbearing and subsequent financial concerns impacting on retirement decision making, impacting

on life satisfaction in later years Key research designs are discussed and evaluated in detail Other themes include the importance of other family commitments in the retirement decision, the impact of early retirement on psychological and cognitive function, and the importance of multidisciplinary research teams This final point is particularly noteworthy, as traditionally, retirement studies draw from various fields such as public health, psychology, economics, and even within psychology sub-disciplines such as developmental, cognitive, and organisational

In the Less successful ageing section, Chapter 8 , MacPherson and Cox in their

con-tribution describe the frontal lobe hypothesis of ageing, which claims that healthy adult ageing is associated with the deterioration of the frontal lobes of the brain (volume, cortical thickness, and white matter) earlier and more severely than other brain areas Due to this selective decline in the frontal lobes, a very distinct cognitive profile is observed in seniors The authors were the first to propose and outline here neuroimaging work from their lab that suggests differential effects of healthy adult ageing on sub-regions of the frontal cortex Indeed, precise anatomical classification techniques have enabled the fractionation of frontal lobes and linkage to dissociable cognitive and psychological processes The authors argue for the dorsolateral pre-frontal theory of cognitive ageing rather than a model based on global impairment of more anterior regions of the brain Healthy and pathological ageing (e.g behavioural variant frontotemporal dementia, Alzheimer’s disease) studies alongside converging, neuropsychological, and neuroimaging work points to the distinctive cognitive pro-files of older compared to younger counterparts Methodological issues associated

with the synthesis of previous work and the design of new studies examining the frontal lobe hypothesis of ageing are considered in detail Methodological issues are evaluated in relation to the contributors’ own work, and difficulties mapping experi-mental work and achieving ecological validity when assessing frontal lobe functions (e.g emotional processing, multitasking) are discussed

In Chapter 9 , the less successful ageing theme is continued with the eration of the psychological and cognitive abilities impaired and spared in type 2 diabetes (DM2) Evidence suggests patients suffer from accelerated ageing in memory domains (particularly episodic) and these impairments have significant impacts on disease management and performance of everyday activities Evaluation

consid-of behavioural work starts the chapter and factors that might account for the mixed findings in the literature are identified (e.g duration of disease, treatment given, and presence of complications) Indeed, exploring potential physiological mechanisms, co-morbid conditions such as glycaemic control, hypertension, dyslipidemia, and how these link to poor cognitive ability provide major challenges to the researcher One solution is to capitalise on new advances in neuroscience (e.g MRI, fMRI, and EEG) and use such tools in the understanding the neuro-cognitive profile of older adults with DM2 This method section of the chapter will prove to be useful for those considering mixed behavioural and neuroscience techniques to disentangle the precise cognitive processes impaired For example, neuroimaging (particularly EEG) has been successfully used to track the precise aspects of episodic memory impaired in ageing and dementia (encoding vs storage vs retrieval)

There has been recent interest in putative protective and risk factors for er’s disease (AD) In particular, dietary factors (e.g consumption of various fats) and lifestyle modifications (e.g physical exercise) have received considerable atten-tion in relation to successful ageing in the presence of disease These modifications are likely to have maximum impact in those who are predisposed (genetically, environmentally) to develop AD at a higher incidence than the population at large Indeed, significant genetic/environmental (e.g apolipoprotein genotype/diet) and environmental/environmental (e.g physical exercise/diet) relationships have been reported in the extant literature In Chapter 10 , those studies are critically evalu-ated by Scholes-Balog and colleagues with a view to providing the groundwork for researchers proposing studies in the area The authors focus on literature impli-cating traumatic head injury as a significant risk factor for Alzheimer’s disease Studies suggest that dietary and lifestyle factors may interact with head injury to influence the risk of cognitive decline and potentially alter the risk of develop-ing AD These interactions may be mediated by common biological processes Notably a proposed conceptual model suggesting that the accumulation of brain amyloid-β represents the most likely candidate mechanism underlying these inter-actions With this model in mind, future research will be able to perform well designed studies in the area

In our section Novel interventions, we learn how music can contribute to enhanced

psychological function and wellbeing even in the latter stages of the disease Music

listening and therapy are the focus of Vink and van Bruggen-Rufi, Chapter 11 , who examine the musical parameters that may be central to music’s emotion arous-ing enhancement properties The historical account is particularly perceptive as

we learn how music and its healing properties have a long history The emotional arousing properties and direct impacts on the brain of music should not be underes-timated and for that reason music therapy can be seen as a remarkable intervention Even in Alzheimer’s disease it is known that musical ability (e.g rhythm) appears preserved during the course of the disease An evaluation of music-based exercise

is undertaken with findings suggesting episodic recall to be superior when stimuli

is presented in songs compared to verbal information alone In keeping with a common theme for successful ageing, music therapy is also of benefit due to the increased social interaction from group work during sessions Together the chapter

is extremely informative and argues strongly for the inclusion of music therapy within general care

The purpose of Chapter 12 (Dr Ioana Petrescu) is to examine novel ventions that may capitalise on creative abilities in the elderly Creative activities such as poetry are evaluated for their utility for enhancing quality of life in the elderly and those individuals with dementia The focus in the chapter is the evaluation of six poetry workshops conducted by the group that resulted in the writing of successful poetry by Alzheimer’s sufferers in an early interven-tion group The accomplishment was exceptional with the work of the group subsequently collected and published in a volume Furthermore, the participants were actively involved in the poetry writing workshops and were proud of their poetry-writing achievements and publication Overall, the work demonstrated the utility of such interventions in successful ageing programmes and the experi-ence was reported to have a positive influence on the sense of self as persons and writers with dementia

The volume draws to a close with an insightful Chapter 13 by Wylie and Smith

on the topic of death, dying, and bereavement Living longer and a protracted dying process due to accompanying chronic disease can place terrible demands on the individual and family caregivers For this reason investigating optimal strategies for end of life care should be treated as a priority area A ‘good death’ focus is empha-sised throughout the chapter with care targeting minimising suffering and distress The authors evaluate Bradbury’s (1999) account of idealised death, which includes dying in one’s own home, having one’s close relatives present, and an alert mind Unfortunately, these conditions are often not met An evaluation of difference between younger and older adults with respect to end of life care and the implica-tions for research and policy suggests the work on seniors is poorly understood

A further concern for researchers promoting a good death in elderly individuals

is that perspectives on the specific components that comprise a good death differ cross-culturally This needs to be kept in mind when developing culturally sensitive care programmes, as potentially good death could be compromised in those from minority backgrounds

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SECTION II

Lifestyle factors and

psychological functioning

Introduction

As people age worldwide, preserving and improving cognition in later life is ing more urgent Most of us share the intuition that physical exercise is a good way to ensure a healthier aging mind After all, many of the older people who are cognitively successful are also physically active This observation has generated a multitude of studies seeking a causal link between physical exercise and cognitive health Indeed, the hundreds of studies that have already been conducted in older adults generally suggest a positive correlation between physical exercise and cogni-tion (for reviews, see Angevaren, Aufdemkampe, Verhaar, Aleman, & Vanhees, 2008; Blondell, Hammersley-Mather, & Veerman, 2014; Colcombe & Kramer, 2003; Kelly

becom-et  al., 2014b) We must be mindful, however, that a positive correlation between exercise and healthy cognition indicates only that they are found in the same people Based merely on correlational evidence, we cannot know whether exercise directly improves cognitive aging or, conversely, whether healthy cognitive aging supports

a more active lifestyle Exercise and cognitive health may be inter-related in more complex ways, and third variables such as social interaction might be keeping peo-ple active and cognitively intact in aging

Most of us prefer the idea that we can influence the course of our cognitive aging through physical and/or mental exercise over the thought of being subject to the uncontrollable fate of cognitive decline Scientists often share this perspective, leading them to frequently adopt the optimistic attitude that age-related cogni-tive decline can be attenuated significantly by physical exercise However, a closer look at the existing data reveals significant methodological limitations that make it surprisingly difficult to establish a direct, causal link between physical exercise and the preservation of cognition in aging Likewise, although cognitive exercise (i.e.,

“brain training”) is becoming an increasingly popular and lucrative intervention to

2

PHYSICAL AND COGNITIVE

EXERCISE IN AGEING

Rabipour, Sheida, Miller, Delyana, Taler, Vanessa,

Messier, Claude and Davidson, Patrick

preserve cognitive function in aging, brain-training studies have suffered from many

of the same challenges as those of physical exercise

In a previous review, we delved into this literature in detail, noting ological issues that make it difficult to confidently infer a direct, causal relationship between physical exercise and cognition in older adults (Miller, Taler, Davidson, & Messier, 2012) Here, we summarize the evidence on the effects of physical and cognitive exercise on cognitive aging, highlight the main methodological challenges

method-in the area, and suggest key questions to consider when undertakmethod-ing research on this topic We point out various factors that deserve serious consideration when evalu-ating existing reports or undertaking new research We conclude with suggestions

to help researchers and practitioners in the design, implementation, and evaluation

of research on physical and cognitive exercise Throughout, we adopt a cautious attitude about causal relationships between exercise and cognitive aging Of course,

as the field accumulates more good data, our approach in this review may prove to

be overly cautious However, as we will outline, we think that at this stage care is warranted in claiming which factors contribute to healthy cognitive aging and in recommending what people do to increase their odds of successful cognitive aging

A general consideration: choosing

the right design for the right question

The overall design of a study determines the questions it can answer Observational

studies can be either retrospective or prospective, including data from one point in time (i.e., cross-sectional) or several (i.e., longitudinal) Their advantages include the possibility of being relatively inexpensive, large, and easy to run Moreover, observa-tional studies can provide insights into cross-sectional and longitudinal differences in cognition and physical exercise Observational designs do not allow us, however, to

establish causality Experimental (or intervention) designs, in contrast, attempt to

system-atically control a variable of interest (i.e., exercise), while reducing the influence of potentially confounding factors In this regard, experiments are better able to uncover causal relationships This design is no panacea, however Interventions are not immune

to confounds, are often costly – which usually leads to smaller sample sizes evaluated over a shorter period of time than ideal – and suffer from selection biases and dropout

Considerations in designing and interpreting

studies of physical exercise and cognition

What, exactly, is physical exercise?

At first glance, this question might seem pedantic, but it is both important and ficult to answer What is the operational definition of exercise in the study? Aside from questions about the duration and intensity of activity (see below for a discus-sion of these), there is little agreement across the literature on exactly which activities count as “exercise.” Most researchers (and participants) would endorse swimming

dif-laps in the pool as an obvious example, but what about gardening? Housework? Sex? Each of these has been included in some previous studies but not others, which, at the very least, hinders the comparison of results across the literature Although uni-versal agreement on the definition of “exercise” seems unlikely, greater consistency and a common vocabulary are needed urgently (Warren et al., 2010)

Another consideration in defining exercise regards the target physiological energy systems An implicit consensus appears to exist across the literature that cardiorespiratory-focused exercise (e.g., swimming, running) contributes the most

to effects on cognition, whereas strength-focused exercise (e.g., weight training) is less effective, followed by balance, toning, and flexibility (e.g., Tai Chi, yoga), which are least effective This distinction often leads researchers to use activities that ostensibly belong to the last of these three categories as a control for activities from one of the first two categories Nevertheless, the evidence for the superiority of cardiovascular exercise is mixed, particularly when one looks at interventions rather than obser-vational studies (Colcombe & Kramer, 2003; Snowden et al., 2011) This may stem from the difficulty in assigning certain physical activities to only one of these three categories For example, many aerobic exercises (e.g., running) cannot help but also yield improvements in strength as well as in balance, toning, and flexibility Conversely, strength training can benefit cardiovascular function, either directly (e.g., by changing arterial stiffness; Li et al., 2014) or indirectly (for example, by increasing a jogger’s core and leg muscle strength to allow her to run further and/or faster, driving her heart rate that much more) Ambiguity surrounding the specific cognitive benefits of particular kinds of exercise may also stem from the possibility that any activity that is physically, cognitively, or socially stimulating can boost cognition (Hayes, Hayes, Cadden, & Ver-faellie, 2013; for more, see “What other factors must be ruled out?”, below)

How should physical exercise be measured?

After deciding which behaviours are defined as exercise, the next challenge is to

measure them Researchers usually choose between subjective and objective measures

Subjective reports (i.e., self-report) can be formalized as questionnaires, diaries, logs, and so forth Although they are inexpensive and easy to administer, their value can

be diminished by participants changing their behaviour or their report to fit what

is socially desirable (i.e., impression management) or what they believe the menters expect or want (i.e., demand characteristics) and by memory failures and biases, which may be especially relevant if participants are asked to recollect details about exercise from long ago The importance of memory may help explain why test–retest reliability of exercise self-reports is notoriously low (Geda et al., 2010) Objective methods of measuring and monitoring exercise vary Laboratory mea-sures include pulse, blood pressure, and the volumes of oxygen and carbon dioxide inhaled and exhaled when breathing under controlled maximal physical exertion, from which we derive the maximum oxygen consumption: VO 2 max This last test is costly, takes significant time, and requires a specialized facility Because the VO 2 max test typically requires participants to reach their maximal cardiorespiratory capacity, it

experi-can be counter-indicated for people with low fitness or signifiexperi-cant health problems

As a real-world alternative, the first generation of personal devices for continuous monitoring of activity (e.g., stand-alone motion sensors, pedometers, accelerometers, and so forth) has now given way to a second generation of more accessible, easier

to use, and less expensive measures These small, discreet wearable sensors detect variables such as heart, pulse and respiration rates, and footsteps (which, depending

on the system, can be categorized into walking, running, and stair-climbing) cally, these allow continuous collection of data using a smartphone New devices are coming onto the market every year, and prices are falling accordingly, increasing the likelihood that such devices will be used in larger studies Of course, these devices are useful only if participants use them properly and continuously

The rapid pace of product development for exercise monitors means that the scientific literature is lagging behind industry by several years For instance, in July

2016, only 100 PubMed entries existed for “FitBit,” one of the most popular wearable monitor companies; more crucially, only one entry existed for “Fitbit and cognition.” The bulk of the current literature on objective monitoring of physical activity has

used the previous generation of devices, which often had problems with comfort and

compliance, especially over the long term Although these problems might be gated by newer technology, caution is warranted in their use: These devices can fail or deliver inaccurate data (Lee, Kim, & Welk, 2014; Sasaki et al., 2014), 1 and the data they

miti-do yield can be difficult to interpret It is possible to estimate VO 2 max from resting and maximum heart rates (Uth, Sorensen, Overgaard, & Pedersen, 2005), but this esti-mate must be acquired during controlled exercise intensity, which may be difficult for all participants to attain without supervision – notwithstanding the risk for older adults exercising at peak intensity (Noakes, Myburgh, & Schall, 1990) Furthermore, some older adults may be uncomfortable using these wearable technologies

Choices about measurement are important, because these different ways of suring exercise are not interchangeable: Although within-subjects studies assessing subjective and objective estimates of exercise generally find positive correlations between subjective and objective measures, these correlations are usually weak (Jurca

mea-et al., 2005; Mailey mea-et al., 2010; Moy, Scragg, McLean, & Carr, 2008; Zlatar mea-et al., 2015)

How much physical exercise is required for

Is more frequent exercise better? The old adage that “more is better” might fit with our intuitions, but might not actually be true (or, the answer might depend

on whether by “more” you mean session schedule [ how often ], session length [ how long ], program length [ over how long a term ], or intensity of activity) For example, in

their classic meta-analysis of exercise interventions for cognitive aging, Colcombe and Kramer (2003) found that programs that lasted more than six months were more effective, implying that more sessions are better However, the “more is better” maxim did not apply to the length of each session: The ideal session length was between 30 and 45 minutes, with longer sessions not conferring as great a benefit to cognition

Is more intense exercise better than less intense? Perhaps going against one’s

intuitions, many interventions and longitudinal studies have suggested that intensity exercise is often as good as, and sometimes even better than, high-intensity exercise (Blondell et al., 2014; Colcombe & Kramer, 2003; Etnier et al., 1997; Gates, Singh, Sachdev, & Valenzuela, 2013; Hindin & Zelinski, 2012; Kelly et  al., 2014b; Lindwall, Rennemark, & Berggren, 2008; Lindwall, Rennemark, Halling, Berglund, & Hassmen, 2007; Smith et  al., 2010; Snowden et  al., 2011; Sofi et  al., 2011; Yaffe, Barnes, Nevitt, Lui, & Covinsky, 2001) Two points seem pertinent, however First, the debate over different effects of low-, moderate-, and high-intensity

moderate-exercise is complicated by the fact that intensity is particularly difficult to measure

and agree on This is especially the case in longitudinal and epidemiological studies, which often rely on self-report Some researchers have chosen to categorize dif-

ferent activities a priori as being high intensity (e.g., jogging, basketball) versus low

intensity (e.g., walking, gardening), but such categorization risks confounding type

of activity with intensity Other researchers (e.g., Hillman et al., 2006) have relied

on people reporting how often they break into a sweat as a proxy for intensity This approach is hindered, however, by the weak relationship between sweating and physical exertion (Buono & Sjoholm, 1988) Moreover, sweating tends to decrease

in aging (Foster, Ellis, Dore, Exton-Smith, & Weiner, 1976) Alternative measures of the intensity of physical activity include multiplying the estimated amount of time taking part in each activity by the amount of energy presumably expended dur-ing that activity (e.g., van Gelder et al., 2004), but in many cases these still rely on participants’ self-reports

Second, an interesting recent development is the introduction of very high

intensity exercise for very brief periods (e.g., 90% maximum heart rate for only

1 minute) Referred to as high intensity training (HIT) or high intensity interval training (HIIT), this usually occurs under the supervision of medical personnel using objective physiological exertion measures Virtually nothing has been pub-lished on the cognitive effects of these very high intensity protocols, but given the claims of beneficial effects on blood sugar regulation and processing and on aerobic capacity (for a review, see Gibala, Little, MacDonald, & Hawley, 2012), this could be

a very fruitful area of research

What are the likely cognitive effects?

Not all cognitive processes are affected equally by aging: Processing speed, executive functions, working memory, and episodic memory are perhaps the most sensitive

(for brief reviews, see Davidson & Winocur, 2010; Drag & Bieliauskas, 2010) bly, these are usually the cognitive domains that receive attention in exercise studies However, universal agreement does not yet exist on this list of cognitive domains,

Sensi-or on how best to measure them using behavioural testing MSensi-oreover, not all older adults decline at the same rate, and some appear to decline little if at all Several chal-lenges exist in interpreting the current literature: First, many studies do not probe cognition in detail, but rather use relatively coarse cognitive screening tools such as the Mini Mental State Exam (Folstein, Folstein, & Mchugh, 1975) Although these tools have the advantages of being brief and easy to administer and score, they may lack the sensitivity to probe cognition with high-enough resolution to detect any subtle benefits of exercise (Gagnon et al., 1990)

Instead, more detailed assays of cognition may often be more appropriate For example, if learning and memory is the target cognitive function, a good tool is the California Verbal Learning Test-II (Fine, Kramer, Lui, Yaffe, & R, 2012; Lamar, Resnick, & Zonderman, 2003) It provides a wealth of informa-tion, allowing the comparison of memory over the short term versus over the longer term, assessing memory in several ways (free recall, category-cued recall, and yes–no recognition), and providing additional information on memory organization and consistency Putting the myriad scores together can allow one to make inferences about the participant’s executive functioning, short-term/working memory, and episodic memory The test includes relatively good (American) norms from across the adult age range, and comparison data from different neurological patient groups (e.g., dementia) It is available in a standard and an alternative version, meaning that it can be administered twice without item-specific practice effects

Of course, the most appropriate cognitive measures depend on the population and cognitive processes of interest (Bahar-Fuchs, Clare, & Woods, 2013) In general, however, researchers should prefer measures with well-established reliability, valid-ity, sensitivity to both potential cognitive gains and losses (including no ceiling or floor effects), and availability in multiple parallel forms to yield minimal (or, at least, predictable) practice effects The California Verbal Learning Test-II meets these criteria reasonably well One special problem to note, however: To avoid ceiling and floor effects these tests must have an appropriate level of difficulty Yet, this

is not always as easy as it sounds Many clinical measures are designed for people with reduced levels of performance, and may be inappropriate for high-functioning participants (such as those healthy, highly-motivated older adults who often sign up enthusiastically for an exercise study) Even the California Verbal Learning Test-II, for all its advantages, has problems with potential ceiling effects in high-functioning individuals (Uttl, 2005)

What are the likely brain effects?

Ideally, cognitive effects of exercise should be accompanied by measurable brain effects Because of the overwhelming number of brain systems and processes that

one could examine, researchers must decide where to focus (for suggestions, see Hayes et al., 2013)

Systems level

Most researchers have taken a macro or systems-level approach, often using tural or functional neuroimaging to examine the whole brain Even when restricting oneself to this level, the possibilities remain numerous: Structural studies can focus

struc-on different registruc-ons of the brain and different tissues (e.g., grey versus white matter), and use different methods (e.g., manual versus semi-automated or automated selec-tion and quantification of volumes) to look at different characteristics Grey matter integrity can be operationalized in terms of the estimated volume or percentage of grey matter in a given slice, compartment, or region, or the thickness of the cortex White matter integrity can be operationalized in terms of the estimated volume or percentage of white matter in a given slice, compartment, or region, the number of discrete lesions evident to a human or computer decision-maker, or spatial patterns

in the movement of water (as in diffusion imaging, which itself can be done in several different ways) Functional studies can focus on one or several regions or on the interaction among them, examining activity at rest or during a cognitive task Note that the two most common functional neuroimaging methods, Positron Emis-sion Tomography (PET; measuring glucose utilization with a radioactive tracer) and the blood oxygenation level dependent signal in functional Magnetic Resonance Imaging (fMRI measuring brain oxygen use), provide different but complementary information about the interactions among brain activity, energy consumption, and blood supply (Detre & Wang, 2002; Lauritzen & Gold, 2003) A final consideration

is that some brain features, such as neurofibrillary tangles, beta-amyloid plaques, and cell loss, are more characteristic of dementia than of healthy aging The choice

of brain variable(s) is important, because some phenomena (e.g., neurofibrillary tangles) cannot easily be detected with neuroimaging, and many of these variables (e.g., beta-amyloid deposition, metabolic changes, and atrophy) are at least partially independent of one another in normal aging and dementia (Chen, Rosas, & Salat, 2011; La Joie et al., 2012; Vemuri et al., 2015) One could imagine exercise having dissociable effects on each of these factors (Radak et al., 2010)

Cellular/molecular level

Although most of the work on exercise and cognition in aged humans has looked at the brain at the macro/systems level (for example, using MRI and PET), the physi-ological mechanisms invoked to explain the cognitive benefits of exercise are usually

at the micro/cellular-molecular level Some researchers emphasize vascular health (e.g., improving neuron-blood supply coupling, reducing risk of stroke by reducing blood pressure and clearing cholesterol, and so forth), which can be summed up

by the adage “What’s good for the heart is good for the brain” (Angevaren et al., 2008) Others emphasize the potential effects of exercise on growth and self-repair