How Interventions Might Improve Cognition in Healthy Older Adults

Many of the cognitive declines in healthy aging are moderated by experience, suggesting that interventions may be beneficial. Goals for aging outcomes include improving performance on untrained tasks, remediating observed cognitive declines, and ensuring preservation of functional ability. This selective review evaluates current progress towards these goals. Most research focuses on untrained tasks. Interventions associated with this outcome include games and exercises practicing specific cognitive skills, as well as aerobic exercise, and modestly benefit a relatively narrow range of cognitive tasks. Few studies have directly tested improvements in tasks on which individuals have been shown to experience longitudinal decline, so this goal has not been realized, though remediation can be examined rather easily. Little work has been done to develop psychometrically strong functional outcomes that could be used to test preservation of independence in everyday activities. Virtual reality approaches to functional assessment show promise for achieving the third goal.

A transformative subfield in rehabilitation science at the nexus of new technologies, aging, and disability

We argue that a silo research and training approach is no longer sufficient to provide real solutions to the complex humanitarian, social, and financial problems brought about by global trends in aging and the increased prevalence of multiple chronic conditions that limit independence and activities of daily living. This perspective highlights the opportunities for collaborative research and training in a new multidisciplinary science of rehabilitation enabled by growing knowledge and information along scientifically and clinically meaningful lines. The recent proliferation of eHealth technologies offers opportunities for development of low-cost, simple, interactive media prevention, health maintenance, and continued functional recovery programs using a chronic care model designed to promote engagement and participation. With two examples - long-term disability consequential to (1) hip fracture and (2) manual wheelchair use - we outline the developing science for a collaborative and transformative nexus team capable of accelerating an understanding of ways to restore independence and improve quality of life, in the long-term. We conclude with a set of recommendations for the design of interactive media systems to both increase acceptability and stimulate research.

Extended practice and aerobic exercise interventions benefit untrained cognitive outcomes in older adults: a meta-analysis

OBJECTIVES

To examine whether therapeutic interventions of extended practice of cognitive tasks or aerobic exercise have led to significant improvement in untrained cognitive tasks.

DESIGN

The PSYCINFO, MEDLINE, and Abstracts in Social Gerontology databases were searched for English-language studies of cognitive interventions of exercise or extended cognitive practice between 1966 and 2010. The final search was in January 2011. Studies included were experimental interventions hypothesizing improvement on untrained cognitive outcomes with pre- and posttests. Studies of varying quality were included and compared.

SETTING

Interventions generally took place in laboratories, in gymnasium facilities, in the home, and outdoors. Experimenters administered testing.

PARTICIPANTS

Forty-two studies with 3,781 healthy older adults aged 55 and older were analyzed.

MEASUREMENTS

Between-group effect sizes (ESs), which account for practice effects on outcome measures, and within-experimental group ESs were computed from untrained cognitive outcome domains, including choice reaction time, memory, and executive function, and compared. ESs were also coded for training type and study quality. Multilevel mixed-effect analyses accommodated multiple outcomes from individual studies.

RESULTS

Extended practice (estimated ES = 0.33, 95% confidence interval (CI) = 0.13-0.52) and aerobic fitness (estimated ES = 0.33, 95% CI = 0.10-0.55) training produced significant between-group ESs, but they did not differ in magnitude. Better study quality was associated with larger ESs.

CONCLUSION

Findings indicate that aerobic and extended cognitive practice training interventions for healthy older adults improve performance on untrained cognitive tasks.

Improvement in memory with plasticity-based adaptive cognitive training: results of the 3-month follow-up

OBJECTIVES

To investigate maintenance of training effects of a novel brain plasticity-based computerized cognitive training program in older adults after a 3-month no-contact period.

DESIGN

Multisite, randomized, controlled, double-blind trial with two treatment groups.

SETTING

Communities in northern and southern California and Minnesota.

PARTICIPANTS

Four hundred eighty-seven community-dwelling adults aged 65 and older without diagnosis of clinically significant cognitive impairment.

INTERVENTION

Random assignment into a broadly available brain plasticity-based computerized cognitive training program experimental group or a novelty- and intensity-matched cognitive stimulation active control. Assessments at baseline, after training, and at 3 months.

MEASUREMENTS

The primary outcome was a composite of auditory subtests of the Repeatable Battery for the Assessment of Neuropsychological Status. Secondary measures included trained task performance, standardized neuropsychological assessments of overall memory and attention, and participant-reported outcomes (PROs).

RESULTS

A significant difference in improvement from baseline to 3-month follow-up was seen between the experimental training and control groups on the secondary composite of overall memory and attention, (P=.01, d=0.25), the trained processing-speed measure (P<.001, d=0.80), word list total recall (P=.004, d=0.28), letter-number sequencing (P=.003, d=0.29), and the cognitive subscale of PRO (P=.006, d=0.27). Previously significant improvements became nonsignificant at the 3-month follow-up for the primary outcome, two secondary measures of attention and memory, and several PROs. Narrative memory continued to show no advantage for the experimental group. Effect sizes from baseline to follow-up were generally smaller than effect sizes from baseline to posttraining.

CONCLUSION

Training effects were maintained but waned over the 3-month no-contact period.

List and text recall differ in their predictors: replication over samples and time

This study tested the hypothesis that latent list and text recall invoke somewhat different processes. A bivariate outcome path model of latent list and text recall evaluated the effects of age, latent speed, working memory, and vocabulary as their predictors. Independent of age, working memory reliably predicted both recall variables, whereas speed reliably predicted list recall only. The relationship between vocabulary and recall was mediated by age, working memory, and speed. The generalizability of this model, based on data from the 1994 testing of the Long Beach Longitudinal Study, was evaluated across samples by testing its invariance on baseline data from an additional panel and for eventual attrition at baseline and at a subsequent testing of retested participants and dropouts. Results showed that the model was invariant over all groups, supporting a replicable distinction between list and text recall.

Cognitive benefits of computer games for older adults

The purpose of this paper is to develop a basis for the hypothesis that digital action games may produce cognitive benefits for older adults. First, a discussion of the relationship between cognitive and physical health shows the increasing weight given to the role of declines in cognition in the development of dependency in older adult population studies. Second, evidence that cognitive training produces 'far transfer' in elders is presented. The key issue is that one approach, known as extended practice training, has been successful in producing far transfer to memory and other processes. Its principles, which are consistent with those associated with positive brain plasticity effects, are identified. Those principles are then related to the mechanics of digital action games, which also have the important added feature of producing the experiences of presence, engagement, and flow, the subjective elements of game play that are likely to sustain interest and emotional investment in the skills practiced so that the play produces cognitive benefits. The specific cognitive abilities proposed to be improved by different types of game genres are outlined, and recent developments in game and interface design that may affect the willingness of older adults to play are described.

A cognitive training program based on principles of brain plasticity: results from the Improvement in Memory with Plasticity-based Adaptive Cognitive Training (IMPACT) study

OBJECTIVES

To investigate the efficacy of a novel brain plasticity-based computerized cognitive training program in older adults and to evaluate the effect on untrained measures of memory and attention and participant-reported outcomes.

DESIGN

Multisite randomized controlled double-blind trial with two treatment groups.

SETTING

Communities in northern and southern California and Minnesota.

PARTICIPANTS

Community-dwelling adults aged 65 and older (N=487) without a diagnosis of clinically significant cognitive impairment.

INTERVENTION

Participants were randomized to receive a broadly-available brain plasticity-based computerized cognitive training program (intervention) or a novelty- and intensity-matched general cognitive stimulation program modeling treatment as usual (active control). Duration of training was 1 hour per day, 5 days per week, for 8 weeks, for a total of 40 hours.

MEASUREMENTS

The primary outcome was a composite score calculated from six subtests of the Repeatable Battery for the Assessment of Neuropsychological Status that use the auditory modality (RBANS Auditory Memory/Attention). Secondary measures were derived from performance on the experimental program, standardized neuropsychological assessments of memory and attention, and participant-reported outcomes.

RESULTS

RBANS Auditory Memory/Attention improvement was significantly greater (P=.02) in the experimental group (3.9 points, 95% confidence interval (CI)=2.7-5.1) than in the control group (1.8 points, 95% CI=0.6-3.0). Multiple secondary measures of memory and attention showed significantly greater improvements in the experimental group (word list total score, word list delayed recall, digits backwards, letter-number sequencing; P<.05), as did the participant-reported outcome measure (P=.001). No advantage for the experimental group was seen in narrative memory.

CONCLUSION

The experimental program improved generalized measures of memory and attention more than an active control program.

Far transfer in cognitive training of older adults

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.

Not your parents' test scores: cohort reduces psychometric aging effects

Increases over birth cohorts in psychometric abilities may impact effects of aging. Data from 2 cohorts of the Long Beach Longitudinal Study, matched on age but tested 16 years apart, were modeled over ages 55-87 to test the hypothesis that the more fluid abilities of reasoning, list and text recall, and space would show larger cohort differences than vocabulary. This hypothesis was confirmed. At age 74, average performance estimates for people from the more recently born cohort were equivalent to those of people from the older cohort when they were up to 15 years younger. This finding suggests that older adults may perform like much younger ones from the previous generation on fluid measures, indicating higher levels of abilities than expected. This result could have major implications for the expected productivity of an aging workforce as well as for the quality of life of future generations. However, cohort improvements did not mitigate age declines.

Estimating age change in list recall in asset and health dynamics of the oldest-old: the effects of attrition bias and missing data treatment

Average change in list recall was evaluated as a function of missing data treatment (Study 1) and dropout status (Study 2) over ages 70 to 105 in Asset and Health Dynamics of the Oldest-Old data. In Study 1 the authors compared results of full-information maximum likelihood (FIML) and the multiple imputation (MI) missing-data treatments with and without independent predictors of missingness. Results showed declines in all treatments, but declines were larger for FIML and MI treatments when predictors were included in the treatment of missing data, indicating that attrition bias was reduced. In Study 2, models that included dropout status had better fits and reduced random variance compared with models without dropout status. The authors conclude that change estimates are most accurate when independent predictors of missingness are included in the treatment of missing data with either MI or FIML and when dropout effects are modeled.

A 10-item Rasch modeled memory self-efficacy scale

A 10-item scale to measure memory self-efficacy was developed from responses to the 33-item Frequency of Forgetting scale of the Memory Functioning Questionnaire (MFQ). Responses to the MFQ from 565 participants in the 1994-1995 wave of the Long Beach Longitudinal Study were analyzed. Rasch scaling procedures were used to select items that discriminated individuals' scoring patterns and that provided non-redundant information about responses. A set of 10 items provided a scale that was reliable across items and persons. Female gender, conscientiousness score, depression score, and list recall predicted individual differences in participants' scores on the scale. Age, education, neuroticism, and text recall were also reliably correlated with scores but were suppressed by the other covariates. The shortened test is predicted by the same covariates as the long version, indicating that it has similar construct validity.

Adult age differences in multiple cognitive functions: differentiation, dedifferentiation, or process-specific change?

Adult age differences in covariance structures of latent variables of vocabulary, list recall, speed, working memory, and text recall, were analyzed to test hypotheses of structural changes with age. There were baseline data from 613 men and women aged 30-97, data from a second wave of testing from 322 people, and complete longitudinal data from 289 people. There were age differences in the size but not configuration of factor loadings cross-sectionally but not longitudinally. There were no changes in factor standard deviations or covariances. Findings did not support models of dedifferentiation with age.

Effects of demographic and health variables on Rasch scaled cognitive scores

OBJECTIVES

To determine whether demographic and health variables interact to predict cognitive scores in Asset and Health Dynamics of the Oldest-Old (AHEAD), a representative survey of older Americans, as a test of the developmental discontinuity hypothesis.

METHODS

Rasch modeling procedures were used to rescale cognitive measures into interval scores, equating scales across measures, making it possible to compare predictor effects directly. Rasch scaling also reduces the likelihood of obtaining spurious interactions. Tasks included combined immediate and delayed recall, the Telephone Interview for Cognitive Status (TICS), Series 7, and an overall cognitive score.

RESULTS

Demographic variables most strongly predicted performance on all scores, with health variables having smaller effects. Age interacted with both demographic and health variables, but patterns of effects varied.

DISCUSSION

Demographic variables have strong effects on cognition. The developmental discontinuity hypothesis that health variables have stronger effects than demographic ones on cognition in older adults was not supported.

Longitudinal hierarchical linear models of the memory functioning questionnaire

Three hypotheses about the nature of self-rated memory as measured by the Memory Functioning Questionnaire (MFQ; M. J. Gilewski, E. M. Zelinski, & K. W. Schaie, 1990) were tested: that ratings reflect memory performance, that personality traits underlie ratings, and that ratings reflect implicit theories of memory change. Baseline scores and 19 year change slopes for the 4 MFQ factor ratings of a sample of 97 participants aged 30-81 were investigated. There were significant mean declines for all MFQ ratings except Frequency of Forgetting and significant individual differences in slopes for Frequency, Retrospective Functioning, and Mnemonics. Personality predicted baseline Frequency and Seriousness ratings and list and text recall slopes predicted Mnemonics slopes. Different mechanisms may underlie baseline ratings and changes in ratings for different factors.

Understanding unfamiliar words in young, young-old, and old-old adults: Inferential processing and the abstraction-deficit hypothesis

Previous research suggests that older adults derive interpretations of unfamiliar words that are less precise than those of young adults (D. McGinnis & E. M. Zelinski, 2000). Thirty-one adults aged 18-37, 27 aged 65-74, and 28 aged 75-87 read passages containing unfamiliar words (1 per passage) and were asked to think aloud during reading. After reading each passage, participants selected meaning-relevant cues and rated the quality of 4 definition options. Compared with the 2 younger groups, the oldest group rated thematic and irrelevant definitions significantly higher, and their think-aloud protocols included more generalized inferences. Results pertaining to cue selection were not significant. Taken together, these results suggest that age differences in meaning derivation may be related to inferential processing that is overgeneralized, providing support for the abstraction-deficit hypothesis.

The Long Beach Longitudinal Study: evaluation of longitudinal effects of aging on memory and cognition

This article outlines the purposes, design, and findings of the Long Beach Longitudinal Study, a multipanel study of adults aged 28 through the upper reaches of the life span. The goal of the study is to identify normal short- and long-term longitudinal changes in memory and cognition across adulthood, and to develop models to explain cognitive changes. Descriptive findings of 3- and 16-year longitudinal change patterns are identified, as well as results suggesting the role of cognitive processing resources and intellectual ability in memory change. Change patterns of the oldest-old, who differ from less elderly adults, are discussed.

The relationship between subjective and objective memory in the oldest old: comparisons of findings from a representative and a convenience sample

OBJECTIVES

To evaluate the hypotheses that subjective memory ratings are more accurate in the oldest old than in the young old and more accurate in a representative sample than in a convenience sample.

METHODS

Outcomes of hierarchical regressions of subjective ratings and participant characteristics on recall were compared between a nationally representative sample of 6,446 adults ages 70 to 103 and a convenience sample of 326 adults ages 70 to 97.

RESULTS

Education interacted with memory ratings in the prediction of performance in the representative sample, with better prediction for more highly educated participants than for participants with lower levels of education.

DISCUSSION

The general pattern of findings was consistent across both samples and neither hypothesis was supported. Possible explanations for the similarity of results across samples are considered.

Age, medical conditions, and gender as interactive predictors of cognitive performance: the effects of selective survival

The interaction of age, medical conditions, and gender on free-recall and mental status test performance was analyzed in two large survey samples of older adults. Age, gender, and the presence of medical conditions interacted with recall and mental status in Study 1 (n = 2,695) and mental status in Study 2 (n = 6,299). For men, those with one or more medical conditions declined more steeply with age than those with no conditions. For women, this relationship was reversed. The findings suggest survival effects, whereby those who lived to old age with medical conditions and were selected into the sample had high levels of cognitive functioning. The age at which these effects are seen vary with gender because women survive longer than men.

Understanding unfamiliar words: the influence of processing resources, vocabulary knowledge, and age

In a 2-experiment design, the authors assessed the role of age and ability in defining unfamiliar words from context. In Experiment 1, 60 adults aged 18-33 and 60 adults aged 61-96 read passages with cues to the meaning of rare words, then defined them. Older adults produced fewer components of the words' meanings and were more likely to produce generalized interpretations of the precise meaning. In Experiment 2, 726 adults aged 30-97 selected definitions from 4 choices: the exact definition, a generalized interpretation of the exact definition, a generalized interpretation of the story, and definition-irrelevant information from the story. Adults over age 75 selected fewer precise definitions and more generalized interpretations of the story than younger ones. Findings suggest that older adults may have special difficulties in deriving the meaning of unfamiliar words from context.

Understanding unfamiliar words: the influence of processing resources, vocabulary knowledge, and age

In a 2-experiment design, the authors assessed the role of age and ability in defining unfamiliar words from context. In Experiment 1, 60 adults aged 18-33 and 60 adults aged 61-96 read passages with cues to the meaning of rare words, then defined them. Older adults produced fewer components of the words' meanings and were more likely to produce generalized interpretations of the precise meaning. In Experiment 2, 726 adults aged 30-97 selected definitions from 4 choices: the exact definition, a generalized interpretation of the exact definition, a generalized interpretation of the story, and definition-irrelevant information from the story. Adults over age 75 selected fewer precise definitions and more generalized interpretations of the story than younger ones. Findings suggest that older adults may have special difficulties in deriving the meaning of unfamiliar words from context.

Individual differences in 16-year memory changes

The authors analyzed the role of individual differences in age, gender, and 16-year declines in reasoning and vocabulary as predictors of 16-year changes in text and list recall and recognition in 82 adults aged 55-81 years at baseline. Declines in reasoning as well as being older at baseline predicted declines in text recall. Male gender and declining in vocabulary predicted declines in list recall. There were no reliable predictors of declines in recognition. The findings suggest that changes in abilities, as well as age and gender, predict declines on memory tasks. However, the specific predictors varied across tasks.