To Örebro University

Introduction: This study aimed to investigate the age trends in various types of memory, including priming, working memory (WM), episodic memory (EM), and semantic memory (SM) from adulthood to old age, as well as the mediating role of inhibition control (IC) in the relationship between age and memory.

Methods: A total of 796 healthy adults aged between 25 and 83 years participated in this cross-sectional study. They underwent assessment using a comprehensive battery of memory tests (adapted from the Betula battery), digit span tasks (to measure WM), and the Stroop colorword test (to measure IC).

Results: The scatter plot with locally estimated scatterplot smoothing (LOESS) fitting line showed EM and WM declined steadily from age 25, while SM exhibited a mild increase up to age 55 followed by a decline. Priming did not show significant changes with age. Mediation analysis and bootstrap tests indicated that IC mediated the relationship between age and EM (beta=-0.097, P=0.002) and between age and SM (beta=-0.086, P=0.001).

Conclusion: Our results showed that age affects various types of memory differently, and inhibition control plays a fundamental mediating role in explaining age-related declines in SM and EM.

BACKGROUND: A common belief among people and some researchers is that keeping yourself mentally active may decrease the risk of dementia. Over the past years, despite widespread efforts to identify proxies for protecting cognitive reserve against age-related changes, it is still not clear what type of intellectual activity would be beneficial for cognitive reserve. To fill this gap, we propose a three-dimensional model of intellectual activity. According to this conceptual model, intellectual activities could be distinguished based on their locations in a three-dimensions space, including; (1) Activation: active vs. passive, (2) Novelty: novel vs. familiar, and (3) Productivity: productive vs. receptive. We assumed that the activities that are categorized as more active, novel, and productive could be considered as a cognitive reserve proxy.

METHODS: To test this hypothesis, a sample of 237 participants older than 50 years (Mage = 58.76 ± 6.66; 63.7% women) was recruited to take part in the study. Episodic, semantic and working memory were assessed with computerized battery tests (Sepidar) and a self-report questionnaire was used to assess intellectual activities. Activities were categorized in terms of; (1) passive, familiar, and receptive activities (radio/watching TV), (2) active, familiar, and receptive activities (solving crosswords), (3) active, novel, and receptive activities (reading), and (4) active, novel, and productive activities (writing).

RESULTS: The results indicated that writing moderates the effect of age on episodic and semantic memory. Reading only moderates the effect of age on semantic memory, and radio/watching TV and solving crosswords do not play a role in moderation analysis.

CONCLUSIONS: Our finding suggests that intellectual activities have different moderating effects on the relationships between age and memory performance. Individuals with high levels of participation in novel and productive activities over the life course are less likely to clinically demonstrate cognitive impairments. Our results support the potential benefit of the three-dimensional model to provide a better insight into the complex role of intellectual activities in cognitive reserve, particularly for older adults. Further research is needed to evaluate the efficacy and the benefits of the model.

The neurobiological underpinnings of action-related episodic memory and how enactment contributes to efficient memory encoding are not well understood. We examine whether individual differences in level (n = 338) and 5-year change (n = 248) in the ability to benefit from motor involvement during memory encoding are related to gray matter (GM) volume, white matter (WM) integrity, and dopamine-regulating genes in a population-based cohort (age range = 25-80 years). A latent profile analysis identified 2 groups with similar performance on verbal encoding but with marked differences in the ability to benefit from motor involvement during memory encoding. Impaired ability to benefit from enactment was paired with smaller HC, parahippocampal, and putamen volume along with lower WM microstructure in the fornix. Individuals with reduced ability to benefit from encoding enactment over 5 years were characterized by reduced HC and motor cortex GM volume along with reduced WM microstructure in several WM tracts. Moreover, the proportion of catechol-O-methyltransferase-Val-carriers differed significantly between classes identified from the latent-profile analysis. These results provide converging evidence that individuals with low or declining ability to benefit from motor involvement during memory encoding are characterized by low and reduced GM volume in regions critical for memory and motor functions along with altered WM microstructure.

Previous research has frequently shown the association between age, Neuroticism, and Openness with memory. However, few studies have investigated the interaction of these factors so far. The present study examined whether the relationship between age and memory is moderated by the Neuroticism and Openness using cross-sectional data from a sample of 550 Iranian participants. They completed the Persian version of the NEO five-factor inventory as well as the memory tests from the Sepidar cognitive test battery. The results indicated that Openness was significantly positively associated with episodic, semantic, and working memory, and the unique effect of Openness on episodic and semantic memory was found even after controlling for the effect of years of education, sex, socioeconomic status (SES), and age. Moderation analysis indicated that Openness moderated the relationship between age and semantic memory as well as age and working memory. Moreover, the results showed that the pathway between age and semantic memory was moderated by Neumticism. This study highlights the interaction between age, personality traits, and memory, which has important theoretical and practical implications for the cognitive reserve in healthy adults.

Introduction: This study aimed to evaluate the reliability and validity of an Iranian computerized memory battery modeled after the Betula study.

Methods: This study aimed to evaluate the reliability and validity of an Iranian computerized memory battery modeled after the Betula study (Nilsson et al., 1997). The researchers developed this battery as an assessment tool in the Sepidar prospective cohort study. One hundred and ninety-nine participants aged 19-83 years were tested extensively on different aspects of memory. Exploratory factor analysis of the data demonstrated factors similar to those reported by the Betula study. 

Results: The authors succeeded to converge the cross-sectional findings of the study and the data from longitudinal studies of memory aging by correcting possible cohort effects. Investigating age differences in episodic and semantic memory factor scores corrected by education and socioeconomic status revealed no significant difference between younger and older adults before ages 53 to 60, though linear age-related declines existed thereafter.

Conclusion: The results support the reliability and construct validity of this computerized battery for memory assessment in Iranian adults.

OBJECTIVE: The main aim of the present study is to investigate the association between different measures of cognitive reserve including bilingualism, mental activities, type of education (continuous versus distributed), age, educational level, and episodic memory in a healthy aging sample.

METHODS: Four hundred and fifteen participants aged between 50 and 83 years participated in this cross-sectional study and were assessed with the Psychology Experimental Building Language Test battery tapping episodic memory. Demographic variables were collected from a questionnaire designed by the research team.

RESULTS: Compared to participants with continuous type of education, those with distributed type performed better in tests of episodic memory, while no differences were found between bilingual and monolingual participants. We additionally found that age negatively predicts episodic memory, whereas playing mind teasers and educational level have positive relationships with episodic memory.

CONCLUSIONS: Our results indicate that higher cognitive reserve, as measured by distributed educational training, higher level of education, and doing regular mental activities, is associated with better performance on episodic memory tasks in older adults. These results were discussed in connection with successful aging and protection against memory decline with aging.

BACKGROUND: The relationship between conscientiousness, mental health and mental illness has been an issue for the last two decades.

AIMS: By using a dual model of mental health, the present study examined a non-linear relationship between conscientiousness and healthy or non-healthy symptoms in two different cultures.

METHOD: Participants in this study were 296 Iranian and 310 Swedish university students (18-24 years of age). We used two different conscientiousness scales; the 12-item conscientiousness subscale of the NEO/FFI as an imported (etic) scale, and a 10-item Iranian conscientiousness scale as an indigenous (emic) and culture-dependent scale.

RESULTS: In both conscientiousness scales, multivariate analysis of variance showed that conscientiousness differentiated among four mental health groups (languishing, troubled, symptomatic and flourishing), although languishing and troubled individuals were less conscientious than flourishing and symptomatic individuals. Furthermore, the non-healthy symptomatic individuals were more conscientiousness than flourishing individuals. The results showed no significant differences between the two cultures in terms of the four mental health categories.

CONCLUSIONS: It was concluded that the relationship between conscientiousness and mental health/mental illness is more a non-linear relationship than a linear one.

Background: The brief version of community screening instrument for dementia (CSI-D) is a neuropsychological tool, which can be used even by non-specialists in primary care settings following a short training. The CSI-D evaluates the cognitive and functional domains of the subjects and includes an informant interview. However, it should be adapted based on literacy level and sociocultural profile of population in each country.

Objectives: The current study examined the validity and reliability of the Persian version of the brief CSI-D in elderly patients of Iran.

Methods: The current descriptive, cross sectional study was conducted on people 60 and over from 16 provinces of Iran with seven different ethnicities and various levels of education (0 - 13 to >= 13 years). The participants consisted of subjects with normal cognition, subjective cognitive impairment (SCI), mild cognitive impairment (MCI), and different types of dementia. Cognitive impairment was diagnosed by a neurologist with expertise in dementia. The psychometric properties were assessed by comparing Persian version of brief CSI-D with the gold standard. Area under ROC curve, optimal cutoff point, and sensitivity and specificity were also calculated.

Results: Data were collected from 262 participants. Of all the participants, 112 were diagnosed with dementia, 64 with MCI, 32 with SCI, and 53 with normal cognition. The best cutoff point for the test-regardless of gender and level of education-was 8.5 compared with 8 - 9 in the original version of CSI-D and also the cutoff point for patient with dementia was 5.5, while it was 4 in the original version.

Conclusions: The Persian version of CSI-D seems to be an accurate and sensitive tool to screen dementia and MCI in primary care setting, especially among low-educated and illiterate people.

BACKGROUND: Population aging motivated a focus in contemporary research on factors, e.g. cognitive functioning, that contribute to 'aging well.' However, something that has been overlooked is relation between memory functioning, determined by objective tests as well as subjective memory ratings, and subjective well-being (SWB).

OBJECTIVES: The aim of the present study was to investigate cross-sectional and longitudinal (cross-lagged) relationships between episodic memory (both subjective and objective) and SWB.

METHOD: A total of 586 older individuals (60-90 years) were assessed on multiple measures of the targeted constructs at baseline (Time 1) as part of the Betula cohort study. Five years later (Time 2), 354 of the participants returned for follow-up measurements and were included in cross-lagged panel analyses.

RESULTS: As expected, objective memory and subjective memory showed a pattern of cross-sectional age deficits and a mean level longitudinal decline was observed for objective memory. By contrast, SWB showed stable mean levels both across age and time. No cross-sectional or cross-lagged associations were observed between SWB and objective memory, whereas subjective memory and SWB showed a cross-sectional association.

CONCLUSION: The results underscore that successful aging is a multifaceted construct with no or only weak associations between the investigated components. However, SWB and rate of change at the individual level should be considered to define successful aging.

Research in action memory for adults has shown that enacted encoding is not only retrieved more frequently but is also faster in comparison to verbal encoding. The aim of this study was to investigate retrieval processes in terms of recall period and recall difficulty for different encoding conditions in school-aged children (8-, 10-, 12-, 14-years old). The participants studied verbal tasks, subject-performed tasks and experimenter-performed tasks, and received immediate and final free-recall tests. The results revealed that older children not only outperformed younger children in terms of accuracy but also outpaced them in all recall periods. Moreover, recalls of subject-performed tasks and experimenter-performed tasks were better and faster compared with verbal encoding on both types of recall test, by increasing throughout the recall periods. These results are discussed in terms of memory strategies and information processing methods. Pedagogic implications for the use of action memory in children's learning are also considered.