Intrinsic functional connectivity mediates the effect of personality traits on depressive symptoms.

BACKGROUND: Personality traits have been proposed as risk factors for depressive symptoms. However, the neural mechanism behind these relationships is unclear. This study examined the possible mediating effect of resting-state functional connectivity networks on these relationships. METHODS: Data from 153 healthy Germans were obtained from the MPI-Leipzig Mind-Brain-Body: Neuroanatomy & Connectivity Protocol database. Network-based statistics were used to identify significant functional connectivity networks that were positively and negatively associated with the personality traits of neuroticism, conscientiousness, and extraversion, with and without demographical covariates. Mediation analyses were performed for each personality trait and depressive symptoms with the significant positive and negative network strengths of the respective personality traits as mediators. RESULTS: Neuroticism, conscientiousness, and extraversion were significantly correlated with depressive symptoms. Network-based statistics identified patterns of functional connectivity that were significantly associated with neuroticism and conscientiousness. After controlling for demographical covariates, significant conscientiousness-associated and extraversion-associated networks emerged. Mediation analysis concluded that only the neuroticism-positive network mediated the effect of neuroticism on depressive symptoms. When age and sex were controlled, the extraversion-positive network completely mediated the effect of extraversion on depressive symptoms. CONCLUSIONS: These findings revealed that patterns of intrinsic functional networks predict personality traits and suggest that the relationship between personality traits and depressive symptoms may in part be due to their common patterns of intrinsic functional networks.

Psychosocial profiles within community-dwelling older adults with Mild Cognitive Impairment: A prevalence and latent profile analysis study.

OBJECTIVES: Mild Cognitive Impairment (MCI) is an at-risk stage for dementia and accurate prevalence studies are lacking in Singapore. From the literature, it is evident that psychosocial factors increase the risk of conversion to dementia. In this study, we sought to establish the prevalence of MCI in Singapore and study the associated psychosocial factors using latent profile analysis. METHOD: 902 community-dwelling older adults, aged between 60 and 99 years old (Mage = 70.48 years), were recruited as part of the Community Health and Intergenerational Study (CHI). They completed neurocognitive assessments and questionnaires on depression and anxiety symptoms, quality of life, social support, satisfaction with life, and social connectivity. Petersen's criteria was used to diagnose MCI. Within the MCI sample, 166 subjects' psychosocial scores were entered into a latent profile analysis to identify profiles of psychosocial functioning. RESULTS: The prevalence of MCI in our sample was 21.5%. They had significantly lower years of education and perceived social support and higher depressive symptoms than the normal ageing group. Three distinct profiles emerged within the MCI group corresponding to a positive (45.2%), neutral (38.5%), and negative (16.3%) pattern of psychosocial scores. These profiles did not differ significantly in terms of demographic or cognitive variables. DISCUSSION: The three psychosocial profiles might reflect the differing implications of MCI on a person's well-being and the negative psychosocial profile might likely be most at risk of conversion to dementia. Future longitudinal studies are required to confirm these implications.

Directional Effects of Social Isolation and Quality of Life on Anxiety Levels Among Community-Dwelling Older Adults During a COVID-19 Lockdown.

OBJECTIVE: The COVID-19 lockdown could see older adults facing increased anxiety levels due to social isolation. Additionally, the lockdown could be more difficult for those with lower Quality of Life (QoL). We aim to understand predictive factors of older adult's anxiety symptoms during the lockdown as it is a main psychological concern of COVID-19. METHODS: Four hundred eleven participants (Mage = 68.95, S.D. = 5.60) completed questionnaires at two time points - before the pandemic and during the lockdown period. Cross-lagged analysis was carried out on two structural equation models - social isolation and anxiety symptoms, and QoL and anxiety symptoms. RESULTS: Baseline social isolation was associated with more anxiety symptoms at follow-up. However, baseline anxiety symptoms were not associated with social isolation subsequently. For QoL and anxiety symptoms, the relationship was bidirectional. CONCLUSION: Older adults who were previously socially isolated and had a lower QoL are particularly vulnerable to the negative psychological impacts of the COVID-19 lockdown.