The serotonin 5-HT1B receptor subtype is involved in the modulation of serotonin release and is a target of interest for neuroreceptor imaging. Previous studies have shown that the serotonin system ...is affected in Parkinson's disease (PD). Cognitive function, frequently impaired in PD, has been linked to the serotonin system. The aim of this study was to examine whether 5-HT1B receptor availability in the brain of healthy subjects and PD patients is associated with measures of cognitive function.
Twelve control subjects and ten PD patients with normal mini-mental state examination scores were included in this study. Cognitive function was evaluated by assessment of semantic, episodic, and working memory, as well as fluency and visual attention. Creative ability, a measure of divergent thinking, was examined with the alternative uses of objects task. PET measurements were performed with the 5-HT1B receptor-radioligand (11) CAZ10419369 using the HRRT system.
PD patients showed statistically significant lower measures of semantic and episodic memory, as well as creative ability, compared with control subjects. Statistically significant positive correlations were found in control subjects between creative ability and average 5-HT1B receptor availability in grey matter, and in PD patients between scores of Beck Depression Inventory-II and creative ability.
Though creativity has been conventionally linked to dopamine function, our findings in control subjects suggest a link between 5-HT1B receptor availability and creative ability. In PD patients, creative ability was significantly associated with depressive symptoms but not with 5-HT1B receptor availability. This finding deserves further investigation in future studies.
Sex differences in declarative memory and visuospatial ability are robust in cross-sectional studies. The present longitudinal study examined whether sex differences in cognition were present over a ...10-year period, and whether age modified the magnitude of sex differences. Tests assessing episodic and semantic memory, and visuospatial ability were administered to 625 nondemented adults (initially aged 35-80 years), participating in the population-based Betula study at two follow-up occasions. There was stability of sex differences across five age groups and over a 10-year period. Women performed at a higher level than men on episodic recall, face and verbal recognition, and semantic fluency, whereas men performed better than women on a task-assessing, visuospatial ability. Sex differences in cognitive functions are stable over a 10-year period and from 35 to 90 years of age.
The Met allele of the Brain-derived neurotrophic factor (BDNF) Val(66)Met polymorphism has been associated with impaired activity-dependent secretion of BDNF protein and decreased memory performance. ...Results from imaging studies relating Val(66)Met to brain activation during memory processing have been inconsistent, with reports of both increased and decreased activation in the Medial Temporal Lobe (MTL) in Met carriers relative to Val homozygotes. Here, we extensively studied BDNF Val(66)Met in relation to brain activation and white matter integrity as well as memory performance in a large imaging (n=194) and behavioral (n=2229) sample, respectively. Functional magnetic resonance imaging (fMRI) was used to investigate MTL activation in healthy participants in the age of 55-75 years during a face-name episodic encoding and retrieval task. White matter integrity was measured using diffusion tensor imaging. BDNF Met allele carriers had significantly decreased activation in the MTL during encoding processes, but not during retrieval processes. In contrast to previous proposals, the effect was not modulated by age and the polymorphism was not related to white matter integrity. Met carriers had lower memory performance than Val homozygotes, but differences were subtle and not significant. In conclusion, the BDNF Met allele has a negative influence on MTL functioning, preferentially during encoding processes, which might translate into impaired episodic memory function.
Studies of successful aging have typically defined elderly who fall in the upper end of a distribution of test scores as successful. A different definition of successful aging requires that older ...adults fall at or above the mean level of younger adults and maintain this level over time. Here we examined this definition of successful aging in a sample of 1463 individuals between the ages of 50 of 85. Based on principal coordinate analysis of cognitive and non-cognitive variables, we identified a group of 55 (8.3%) 70-85 years olds that were high functioning. This group of elderly showed elevated performance on a range of cognitive tasks. Non-cognitive factors that characterized this group included education and subjective health. The participants were retested 5 years later and the same type of analysis was repeated. Of the remaining individuals who initially were classified as high functioning, 18 (35%) remained high functioning and thus met the definition for successful aging. Years of education was a significant predictor of who remained successful over time.
Abstract Salthouse claims that cognitive aging starts around 20 years of age. The basis for this claim is cross-sectional data. He dismisses longitudinal data, which typically show the cognitive ...decline to start much later, around 60 years of age. He states that longitudinal data cannot be trusted because they are flawed. There is a confounding between the effects of maturation and retest effects. We challenge Salthouse's strong claim on four accounts.
Rationale: To allow for interdisciplinary research on the relations between socioeconomic conditions and health in the ageing population, a new anonymized longitudinal database - the Linnaeus ...Database - has been developed at the Centre for Population Studies at Umeå University. This paper presents the database and its research potential. Design: Using the Swedish personal numbers the researchers have, in collaboration with Statistics Sweden and the National Board for Health and Welfare, linked individual records from Swedish register data on death causes, hospitalization and various socioeconomic conditions with two databases - Betula and VIP (Västerbottens Intervention Programme) - previously developed by the researchers at Umeå University. Whereas Betula includes rich information about e.g. cognitive functions, VIP contains information about e.g. lifestyle and health indicators. Population and sample size: The Linnaeus Database includes annuall updated socioeconomic information from Statistics Sweden registers for all registered residents of Sweden for the period 1990 to 2006, in total 12,066,478. The information from the Betula includes 4,500 participants from the city of Umeå and VIP includes data for almost 90,000 participants. Both datasets include cross-sectional as well as longitudinal information. Potential: Due to the coverage and rich information, the Linnaeus Database allows for a variety of longitudinal studies on th relations between, for instance, socioeconomic conditions, health, lifestyle, cognition, family networks, migration and working conditions in ageing cohorts. Conclusions: By joining various datasets developed in different disciplinary traditions new possibilities for interdisciplinary research on ageing emerge.
This study investigated demographic and cognitive correlates of cued odor identification in a population-based sample from the Betula project: 1906 healthy adults varying in age from 45 to 90 years ...were assessed in a number of tasks tapping various cognitive domains, including cognitive speed, semantic memory and executive functioning. The results revealed a gradual and linear deterioration in cued odor identification across the adult life span. Overall, females identified more odors than men, although men and women performed at the same level in the oldest age cohort (85–90 years). Hierarchical regression analyses revealed that age, sex, education, cognitive speed and vocabulary were reliable correlates of performance in the odor identification task. In addition, age-related deficits in the included demographic and cognitive variables could not fully account for the observed age-related impairment in identification, suggesting that additional factors are underlying the observed deterioration. Likely candidates here are sensory abilities such as olfactory detection and discrimination.
Aging patterns in WAIS-R Block Design Test (BDT) were examined cross-sectionally and longitudinally. One sample (35–80 years,
n
=
1000) was assessed in 1988–1990 and five years later (836 returned). ...An independent cohort-matched sample (
n
=
974) was assessed at Time 2 to control for practice effects. Relations between BDT, gender, and education were examined. The cross-sectional analyses indicated a gradual age-related deterioration from 35 to 85 years. By contrast, the longitudinal data indicated stable performance from age 35 to 55, even when minor practice effects were adjusted for, and decline past age 55. Education-adjusted cross-sectional differences revealed similar patterns. A minor, age- and time invariant, male advantage was observed. Education predicted time-related change in BDT, such that higher education was associated with lesser decline. Collectively, the results demonstrate the need to control for cohort and retest effects in cross-sectional and longitudinal studies, and reveal interesting relations between BDT performance and demographic variables.
We investigated time-related patterns in levels of cognitive performance during the period from 1970 to 1993 based on data from Swedish draft boards. The conscripts, including more than a million ...18–19-year old men, had taken one of two versions of the Swedish enlistment battery (SEB67; 1970–1979 or SEB80; 1980–1993), each composed of four subtests. The results revealed significant Flynn effects, with estimated gains of 1.2–1.5 IQ-units per decade. The effect seem to hold across ability levels, even though tendencies of more pronounced effects in the lower half of the ability distribution was observed. The largest gains were for visuospatial tests (Paper Form Board and Metal Folding), with little change, even slight losses during the second sub-period, for tests of verbal knowledge (Concept Discrimination and Synonyms) and a mixed pattern for a test of technical comprehension (losses followed by gains). Finally, comparisons of trends in cognitive performance and in standing height show that the gains in cognitive performance over the years from 1980 to 1993 occurred in the absence of overall gains in height, which speaks against nutrition as the cause of the Flynn effects.