Robert F. Kennison

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.

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.

Cognitively Stimulating Activities: Effects on Cognition across Four Studies with up to 21 Years of Longitudinal Data

Engagement in cognitively stimulating activities has been considered to maintain or strengthen cognitive skills, thereby minimizing age-related cognitive decline. While the idea that there may be a modifiable behavior that could lower risk for cognitive decline is appealing and potentially empowering for older adults, research findings have not consistently supported the beneficial effects of engaging in cognitively stimulating tasks. Using observational studies of naturalistic cognitive activities, we report a series of mixed effects models that include baseline and change in cognitive activity predicting cognitive outcomes over up to 21 years in four longitudinal studies of aging. Consistent evidence was found for cross-sectional relationships between level of cognitive activity and cognitive test performance. Baseline activity at an earlier age did not, however, predict rate of decline later in life, thus not supporting the concept that engaging in cognitive activity at an earlier point in time increases ones ability to mitigate future age-related cognitive decline. In contrast, change in activity was associated with relative change in cognitive performance. Results therefore suggest that change in cognitive activity from ones previous level has at least a transitory association with cognitive performance measured at the same point in time.

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.

Dynamic Associations of Change in Physical Activity and Change in Cognitive Function: Coordinated Analyses of Four Longitudinal Studies

The present study used a coordinated analyses approach to examine the association of physical activity and cognitive change in four longitudinal studies. A series of multilevel growth models with physical activity included both as a fixed (between-person) and time-varying (within-person) predictor of four domains of cognitive function (reasoning, memory, fluency, and semantic knowledge) was used. Baseline physical activity predicted fluency, reasoning and memory in two studies. However, there was a consistent pattern of positive relationships between time-specific changes in physical activity and time-specific changes in cognition, controlling for expected linear trajectories over time, across all four studies. This pattern was most evident for the domains of reasoning and fluency.

Social Activity and Cognitive Functioning Over Time: A Coordinated Analysis of Four Longitudinal Studies

Social activity is typically viewed as part of an engaged lifestyle that may help mitigate the deleterious effects of advanced age on cognitive function. As such, social activity has been examined in relation to cognitive abilities later in life. However, longitudinal evidence for this hypothesis thus far remains inconclusive. The current study sought to clarify the relationship between social activity and cognitive function over time using a coordinated data analysis approach across four longitudinal studies. A series of multilevel growth models with social activity included as a covariate is presented. Four domains of cognitive function were assessed: reasoning, memory, fluency, and semantic knowledge. Results suggest that baseline social activity is related to some, but not all, cognitive functions. Baseline social activity levels failed to predict rate of decline in most cognitive abilities. Changes in social activity were not consistently associated with cognitive functioning. Our findings do not provide consistent evidence that changes in social activity correspond to immediate benefits in cognitive functioning, except perhaps for verbal fluency.

Changes in sobriety in the Swedish population over three decades: age, period or cohort effects?

Aims This study aimed to examine age, cohort and period trends in alcohol abstinence. Design Two surveys, the Level of Living Survey collected in 1968, 1974, 1981, 1990 and 2000, and the Swedish Panel Study of the Oldest Old (SWEOLD) collected in 1992 and 2002, were studied with graphical depictions of cross-sectional and longitudinal data presented over time and over age. Cross-sectional 10-year age group differences, time-lag differences between waves and within-cohort differences between waves for 10-year birth cohorts were examined. Logistic regression models were applied to confirm the observed patterns. Setting The samples were representative of the Swedish population. Participants Participants ranged in age from 18 to 75 (n = 5000 per wave), and 77+ at later waves (n = 500). Measurements Alcohol abstinence was determined by asking ‘Do you ever drink wine, beer, or spirits?’, where a ‘no’ response indicated abstinence. Findings Decreases in abstinence rates were observed from 1968 to 2000/02. While cross-sectional analysis indicated increased abstinence with advancing age, the longitudinal analysis suggested otherwise. Inspection of cohort differences revealed little change within cohorts and large differences between cohorts; abstinence rates declined in later-born cohorts up to the 1940s birth cohorts; stability was observed in cohorts born since the 1940s. Logistic regression models indicated that neither age nor period were significant (P > 0.05) predictors of abstinence when cohort (P < 0.001) was included. Conclusion Decreasing proportions of total alcohol abstainers in Sweden from 1968 to 2000 appear to be attributable primarily to decreases in successive cohorts rather than drinkers becoming abstainers.

Alcohol abstinence, non-hazardous use and hazardous use a decade after alcohol-related hospitalization: registry data linked to population-based representative postal surveys

BackgroundAlthough there is evident association between alcohol-related hospitalization and alcohol use, the relationship has not been well examined. This study analyzed the extent of alcohol abstinence, non-hazardous use and hazardous use among people who had experienced alcohol-related hospitalization during the preceding decade.MethodRegistry data concerning alcohol-related hospitalizations between 1996 and 2007 were linked to two representative surveys, in 2006 and 2007, of residents of Stockholm County. Relevant contrasts were modeled, using logistic regression, in the pooled sample (n = 54 955). Ages were 23–84 years at follow-up.ResultsAmong persons previously hospitalized (n = 576), half reported non-hazardous use. Non-hazardous use was less prevalent than in the general population – and the extent of non-hazardous use did not change over time following hospitalization. There were no significant age differences, but non-hazardous use was less frequent among people with repeated episodes of care. One in six was abstinent. Abstinence was more common among the old, while hazardous use (exceeding 14 drinks per week for men, and 9 drinks per week for women) decreased with age. Abstinence also increased over time; among persons hospitalized ten years ago, the abstinence rate was twice that of the general population. Associations with hazardous use over time were less conclusive. Hazardous use among those previously hospitalized decreased over time in one sample but not in the other. After pooling the data, there were indications of a decrease over time following hospitalization, but more prevalent hazardous use than in the general population.ConclusionsFollowing alcohol-related hospitalization, abstinence increased, and there was no evidence of regression towards the mean, i.e., towards non-hazardous use. Abstinence was also more widespread among previously hospitalized persons of older ages. With advancing age, changing hazardous alcohol habits among previously hospitalized appears to yield a trend towards promotion of abstinence.

The Role of Cognitive Control in Older Adult Cognitive Reappraisal: Detached and Positive Reappraisal

Older adults are more likely to regulate their emotions by engaging in cognitive reappraisal. However, depending on the type of cognitive reappraisal used, efforts to regulate emotions are sometimes met with success and other times with failure. It has been suggested the well-known age-related decline in cognitive control might be the culprit behind the poor use of detached reappraisal by older adults. However, this possibility has not been thoroughly investigated. In addition, studies have not examined what aspects of cognitive control– shifting, updating or inhibition–might be relevant to cognitive reappraisal. In the present study, 41 older participants were tested on cognitive control and abilities to use detached and positive reappraisal. Results showed detached reappraisal compared to positive relied more heavily on cognitive control, specifically mental set shifting. Results of this study have important implications for development of cognitive training interventions for older adults.

Identification of Spline Functions and Cohort Differences in Psychometric Measures of the Long Beach Longitudinal Study

Background:Although declines in psychometric measures with age are often reported, few studies have examined changes with models that allow for identification of multiple splines where the rate of average decline may shift in old age. Zelinski and Kennison (2007) examined age and cohort effects in five psychometric ability measures with linear growth curve models, where two-piece splines with a common knot fixed at age 74 were fit to all five measures. It is likely, however, that the different measures are each associated with unique change functions that may include more than two splines andmultiple knot points. Thus, in the present study, unique change functions were identified for each of the measures with Multivariate Adaptive Regression Splines (MARS).Methods: Five Long Beach Longitudinal Studymeasures, reasoning, space, list recall, text recall, and vocabulary, representing two cohorts born 16 years apart, were modeled over ages 60 to 85 (n € Eœ 950). Scores were calibrated to Rasch scales with a possible 0-100 range. Empirically determined age-related changes in each measure were examined with MARS analyses. Possible cohort interactions in identified change functions were also identified.Results: Age:As shown in Figure 1, declines were universally observed, yet change rates and spline functions differed betweenmeasures. Reasoning showed steady declines beginning at the earliest age modeled (age 60), but the decline rate slowed after age 74. Space showed linear declines after age 66.8. List showed declines after age 64.3. Text showed declines after age 66.4. Vocabulary was stable up to age 73.9, declined from 73.9 to 83.4, and then recovered. Cohort: The later born cohort performed better than the earlier born cohort at the intercept for all measures except vocabulary, which showed no cohort effect. For reasoning and list recall the advantage maintained by the later born cohort diminished in later age. Conclusions: The use of an exploratory approach to identifying multiple linear functions with MARS produced results similar to those of Zelinski & Kennison (2007). However, these new findings also showed that the empirically identified deflection points varied by measure. Vocabulary showed relative stability up to the mid 70s before it declined. Space, list recall, and text recall were associated with initial declines beginning in the mid to late 60s. Reasoning was the only measure associated with initial declines at age 60. While the later born cohort outperformed the earlier born cohort at younger ages, this advantagewas reduced or eliminated in very old age suggesting greater cognitive reserve enjoyed by the later born cohort may be reduced late in life.