Working memory, intelligence and knowledge base in adult persons with intellectual disability.

Previous studies have suggested that performance in working memory (WM) tasks is deficient in all etiologies and at all levels of intellectual disability (ID). Knowledge about WM structure, cognitive processes reflected in WM tasks, or the long-term memory contribution to WM capacity in ID is. however, not satisfactory. In the present study, WM capacity, WM task requirements, as well as effects between WM, skills, knowledge base, and intelligence were explored in two groups with matched fluid intelligence: adult persons with ID and normally developing children aged 3-6 years. The ID Group performed equally well as the children in WM tasks based on familiar semantic information and were significantly better on all measures reflecting skills and knowledge base. The Child Group performed better in phonological and visuo-spatial WM tasks including nonsemantic information, respectively. In particular, it appeared that the groups differed in their WM performance although they were matched for fluid intelligence. We hypothesize that the ID Group depended more on knowledge support from long-terrm memory whereas the Child Group could benefit more from efficient online WM processes.

Meaning in life in three samples of elderly persons with high cognitive functioning.

The study examined the relationships between meaning in life and cognitive functioning in three elderly samples. The participants in Sample I were 78 persons aged 82-87, in Sample II 182 persons aged 83-92, and in Sample III 299 persons aged 65-69. The samples took part in interviews and cognitive tests in 1996-1997. Several interview questions together with the Sense of Coherence questionnaire were used to study the degree and content of meaning in life. Cognitive functioning was measured by Digit Span, Digit Symbol, and Word Fluency in Sample I and Mini-D in Samples II and III. Each sample was divided into the group of persons with high cognitive functioning (including those whose results in cognitive tests fell in the top third of their age cohort) and the comparison group (including the rest of the sample). The analysis showed no difference between the groups in the degree of meaning in life in any of the three samples. The content of meaning in life differed in the two groups: human relationships were reported as a reason for meaning in life and a source of strength in life more often by the persons with high cognitive functioning than by the comparison group. Moreover, those with high cognitive functioning reported that they had taken up a new activity (especially one involving social interests) that gave a sense of meaning in life after retirement more often than the comparison group. Death had positive meaning for the majority of the participants and the groups did not differ in meaning of death. The interactions between the various measures of meaning in life showed that having a sense of coherence and zest for life were factors related to the sense of meaningfulness in life. Meaning of death was not related to other measures.

Tower of Hanoi and working memory in adult persons with intellectual disability.

Persons with intellectual disability (ID) have been found to perform more poorly than their mental age would suggest in the visuo-spatial problem solving task Tower of Hanoi (TOH). Inefficient performance has been assumed to be related to inability to use sophisticated problem solving strategies because of restricted working memory capacity. In the present study, the TOH performance of adult persons with ID was found to be equal to that of fluid-intelligence-matched general children. However, persons with ID violated the rules of the TOH more often, and needed more trials to solve the TOH problems than the children did. Visuo-spatial and executive working memory tasks were significantly connected to the TOH performance of persons with ID, whereas phonological working memory tasks were not. Poor inhibition ability was related to the poor performance of subjects with ID in the TOH. We suggest that for persons with ID, TOH performance is determined by individual differences in fluid intelligence, controlled attention, and inhibition ability.

Working memory and everyday cognition in adults with Down's syndrome.

A number of previous studies have suggested that young people with Down's syndrome (DS) have a specific deficit of the phonological loop component of the working memory. However, there have also been studies which have proposed a specific deficit of the central executive component of working memory and suggested similarities of working memory functioning with patients with Alzheimer's disease. Fifteen middle-aged people with DS were matched for their individual scores of non-verbal intelligence to 15 individuals with mixed aetiology of intellectual disability. A versatile range of tasks was used in order to evaluate the functioning of working memory components. In addition, several everyday cognition skills were assessed. The subjects with DS performed significantly more poorly in all tasks assessing the phonological loop. Performance in other working memory tasks and compound variables representing different working memory components was equal in the groups. In addition, both groups had equal everyday cognition skills. The functioning of the phonological loop seems to be clearly deficient in people with DS. Interestingly, the deficit does not seem to affect the vocabulary or other everyday cognition skills in individuals with DS. No signs of specific deficit of the central executive component of working memory were found.

Meaning in life as an important component of functioning in old age.

The purpose was to locate different measures of meaning in life in a multidimensional space of functioning in old age. Fifty-five persons born in 1910 and 1914 participated in laboratory tests, a medical examination, and interviews over a three-year period from 1994 to 1997. Measures of meaning in life included a sense of meaning in life, a sense of coherence, and four indices derived from a life-line drawing (linearity, trend, mean level in the past, and mean level in the future). The other measures of functioning were the number of chronic diseases, functional disability, walking speed, self-rated health, cognitive capacity, provision of social relationships, loneliness, depressive mood, number of activities, life satisfaction, and wisdom. Using a multidimensional scaling method, a two-dimensional model of functioning was arrived at. In the first dimension, "subjective vs. objective," all the measures of meaning in life were located in the subjective half. The location of the measures along the second dimension, "psychosocial vs. physical," varied considerably. Some of the measures of meaning in life (a sense of coherence, life-line trend, and linearity) were located in the physical half, while others (sense of meaning in life, life-line mean level in the past) were in the psychosocial half The life-line mean level in the future was located in the center of the dimension. The space of functioning provided a novel and illustrative approach to functioning as a multifaceted behavioral competence with meaning in life as an integral part of it.

Working memory structure and intellectual disability.

The working memory of people with intellectual disability has been found to generally lag behind their mental age. However, studies concerning the structure of working memory or its connections to other cognitive functions are rare. The present study employs a versatile battery of tests for the evaluation of working memory structure in adults with intellectual disability of unknown aetiology. In addition, connections between working memory and cognitive skills valid for everyday functioning are evaluated. Working memory performance in the study participants was found to stem from two distinct components which could be regarded to represent phonological and general working memory. General working memory was closely related to intelligence, whereas phonological working memory was not. The subjects in the study group differed in their working memory profiles. These distinct profiles were significantly related to academic skills (e.g. reading, writing and mathematics) and sentence comprehension because the profile of the working memory predicted these abilities even when the intelligence and educational background of the participants was taken into consideration.

Life expectancy of people with intellectual disability: a 35-year follow-up study.

A 35-year follow-up study based on a nation-wide population study of the life expectancy of people with intellectual disability (ID) was undertaken. The study population consisted of a total of 60,969 person-years. A prospective cohort study with mortality follow-up for 35 years was used and the life expectancy of people with ID was calculated for different levels of intelligence. Proportional hazard models were used to assess the influence of level of intelligence and associated disorders on survival. People with mild ID did not have poorer life expectancy than the general population and subjects with mild ID did not have lower life expectancy in the first 3 decades of life. In cases with profound ID, the proportion of expected life lost was > 20% for almost all age groups. The female preponderance was manifested from the age of 60 years onwards, 25 years later than in the general population. Respectively, survival between sexes differed less. Epilepsy and/or hearing impairment increased the relative risk of death for all levels of ID. The prevalence of people with ID over 40 years was 0.4%. People with ID now live longer than previously expected, and the ageing of people with mild ID appears to be equal to that of the general population, posing new challenges to health care professionals.

Acceptance and use of technological solutions by the elderly in the outdoor environment: findings from a European survey.

This article examines the use and acceptance of ticket machines, automatic teller machines (ATMs) and telephone cards by the elderly in four European regions. The analyses are based on data from an international project entitled "Keeping the Elderly Mobile", collected in Mannheim (former West Germany; N = 404 home-dwelling respondents), Chemnitz (former East Germany; N = 400), Ancona (Italy; N = 600), and Jyväskylä (Finland; N = 618). The random sample was stratified by age and gender in each country. Two generations of men and women (aged 55-74 and 75+ years, respectively) participated in the study. Results show that respondents generally made little use of the three technologies under investigation: in fact, the majority of respondents does not use them at all. The most frequently used devices were ATMs in Chemnitz and ticket machines and telephone cards in Mannheim. On the basis of logistic regression analysis, age was the most important explanatory factor for the three technologies and for all four regions, i.e., the users were mostly the "young-old." Education was a more important variable than gender. In all four regions, the majority of the respondents who used the technologies assessed felt that each of them made life easier; nevertheless, ticket machines make life more difficult to almost every third user in Mannheim. Interesting differences and similarities among the towns were also found. The present study exhibits preliminary results regarding elderly and technology which future research should investigate in greater depth.

Changes in intensity of physical exercise as predictors of depressive symptoms among older adults: an eight-year follow-up.

BACKGROUND: Epidemiological research suggests that regular physical activity may be associated with reduced depressive symptoms. The present study examines the predictive value of physical exercise in relation to depressive symptoms among samples of adults aged 65+ during an 8-year period. METHODS: The subjects (N = 663) who participated both at the baseline (1988) and the follow-up (1996) interviews were selected for the analyses. The dependent variable depressive symptoms was assessed by the Finnish modified version of Beck's 13-item depression scale. The independent variable was the intensity of physical exercise. RESULTS: The intensity of physical exercise decreased among the older men and women. Those who had reduced their intensity of physical exercise during the 8 years reported more depressive symptoms at the follow-up than those who had remained active or increased their physical activity. Depressive symptoms were predicted by the intensity of baseline physical exercise, earlier depressive symptoms, older age, gender, having three or more chronic somatic conditions, and difficulties in performing ADL activities. CONCLUSIONS: Age-related decrease in the intensity of physical exercise increases the risk of depressive symptoms among older adults. This calls for effective measures in maintaining and supporting an adequate level of physical exercise among the aging population.

Outdoor mobility and social relationships of elderly people.

Social relationships and activities are important elements in the quality of life of older people. With advancing age, they are made more difficult through the possible loss of physical functions, through societal processes of differentiation, and through unfavourable environmental and technological conditions. Therefore, mobility becomes a fundamental prerequisite for the participation in social relations and activities. This article presents some initial findings of a project which investigates the mobility needs of the elderly and the main factors hindering their desired mobility in three European countries. It became apparent that there is a clear connection between the social situation of elderly persons and specific mobility patterns: if they are tied into a closely meshed network of family or friends, then they are away from home more frequently than when this is not the case. In addition, individual factors like the age, the health situation and the driving ability of a person are important influences. External factors which restrict the mobility can be found in the respective spatial or technical conditions, on the one hand, and in affecting social interactions in the public sphere on the other hand.

Cognitive functioning of 75- and 80-year-old people and changes during a 5-year follow-up.

The aim of the study was to analyze cognitive functioning among two cohorts of elderly people, aged 75 and 80 years at baseline, and changes in the functioning during a five-year period. Cognitive functioning was assessed using psychometric tests, neuropsychological tasks, metacognitive self-evaluations, cognitive screening tests and reaction time tasks. The objective methods correlated significantly with each other, and only one general factor was clearly produced by the factor analyses. However, the speed of cognitive processing was concluded to have a central meaning in the kind of assessments used in this study. Selective attrition affected the results of psychometric and neuropsychological methods; subjects with better cognitive functioning participating in the follow-up assessments. Among those retested, the cognitive level decreased significantly, but the magnitude of the decline was usually low. Differences between the men and the women were mostly nonsignificant. The retest correlations were high in the psychometric tests but lower in many of the neuropsychological and metacognitive methods. Connections between the metamemory scores and the objective test scores were variable.

Difficulties in mobility among elderly people and their association with socioeconomic factors, dwelling environment and use of services.

The purpose of this study was to clarify the extent to which elderly people have difficulties in mobility, and determine their association with socioeconomic factors, dwelling environment and use of services. The study groups were composed of two random samples of 800 persons aged 65-74 and 75-84, respectively. In all, 1224 non-institutionalized persons (80%) were interviewed at home. The respondents were asked to assess their ability to get about the house, negotiate stairs and walk outdoors, as well as manage certain physical exercise tasks. Difficulties in getting about outdoors were found most frequently among the women in the older age group (52% reported difficulties), and least frequently among the women in the younger age group (23%). Logistic regression analyses showed that difficulties in getting about outdoors were significantly explained by length of education and defects in the dwelling environment. Also, difficulties in getting about outdoors explained significantly the use of home help. It is concluded that difficulties in mobility among elderly people, especially among elderly women, should be reduced more actively either by improving their physical abilities or by developing compensation strategies for their own use or in regard to the environment.

Physical activity and psychological well-being among people aged 65 to 84 years.

This report deals with the findings of an epidemiological interview carried out among two representative samples (n = 800 + 800) consisting of persons born in 1904-13 and in 1914-23, and living at home in the year 1988 in the city of Jyväskylä, central Finland. The participation rate was 80% (n = 1244). It appeared that overall involvement in physical exercise decreased with increasing age, especially among the women. About 50% of the subjects carried out regular walking exercise and 40% practised some form of home gynastics which was considered not to be very intensive. About 20% of the subjects were no more physically active than was essential for performing their daily activities. According to log-linear and regression models, there was a significant association between higher prevalence of depression and no regular physical exercise. Self-rated meaningfulness of life and better subjective health were also significantly related to regular and intensive physical exercise. These relationships were more obvious among the younger cohort (65-74 years). The results suggest that involvement in physical exercise may promote positive perceptions of psychological well-being among the elderly. On the other hand, psychological well-being seemed to be an important predictor for staying physically active at advanced ages. These findings are based on a cross-sectional study and therefore leave open the question of direction of causality which will be pursued in a follow-up survey.