The relationship between physical activity, sleep duration and depressive symptoms in older adults: The English Longitudinal Study of Ageing (ELSA)

Research to date suggests that physical activity (PA) is associated with distinct aspects of sleep, but studies have predominantly focused on sleep quality, been carried out in younger adults, and have not accounted for many covariates. Of particular interest is also the reported relationship between physical activity and depression in older adults and as such, their associations with sleep duration. Here we examine the cross-sectional relation between physical activity and sleep duration in a community-dwelling sample of 5265 older adults from the English Longitudinal Study of Ageing. We analysed the data using multiple regression, with physical activity as a categorical exposure and sleep duration a continuous outcome, as well as testing the interaction between physical activity and depressive symptoms, which was significant (p  0.05). Our findings suggest that a potentially effective way of improving sleep in older adults with depressive symptoms is via physical activity interventions

Differences in pre-sleep activity and sleep location are associated with variability in daytime/nighttime sleep electrophysiology in the domestic dog

The domestic dog (Canis familiaris) is a promising animal model. Yet, the canine neuroscience literature is predominantly comprised of studies wherein (semi-)invasive methods and intensive training are used to study awake dog behavior. Given prior findings with humans and/or dogs, our goal was to assess, in 16 family dogs (1.5–7 years old; 10 males; 10 different breeds) the effects of pre-sleep activity and timing and location of sleep on sleep electrophysiology. All three factors had a main and/or interactive effect on sleep macrostructure. Following an active day, dogs slept more, were more likely to have an earlier drowsiness and NREM, and spent less time in drowsiness and more time in NREM and REM. Activity also had location- and time of day-specific effects. Time of day had main effects; at nighttime, dogs slept more and spent less time in drowsiness and awake after first drowsiness, and more time in NREM and in REM. Location had a main effect; when not at home, REM sleep following a first NREM was less likely. Findings are consistent with and extend prior human and dog data and have implications for the dog as an animal model and for informing future comparative research on sleep

A cross-cultural exploratory study of health behaviours and wellbeing during Covid-19

© 2021 The Authors. Published by Frontiers Media. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.3389/fpsyg.2020.608216This study explored the influence of the COVID-19 pandemic on perceived health behaviours; physical activity, sleep, and diet behaviours, alongside associations with wellbeing. Participants were 1140 individuals residing in the UK (n = 230), South Korea (n = 204), Finland (n = 171), Philippines (n = 132), Latin America (n = 124), Spain (n = 112), North America (n = 87), and Italy (n = 80). They completed an online survey reporting possible changes in the targeted behaviours as well as perceived changes in their physical and mental health. Multivariate analyses of covariance variance (MANCOVA) on the final sample (n = 1131) revealed significant mean differences regarding perceived physical and mental health ‘over the last week’, as well as changes in health behaviours during the pandemic by levels of physical activity and country of residence. Follow up analyses indicated that individuals with highest decrease in physical activity reported significantly lower physical and mental health, while those with highest increase in physical activity reported significantly higher increase in sleep and lower weight gain. UK participants reported lowest levels of physical health and highest increase in weight while Latin American participants reported being most affected by emotional problems. Finnish participants reported significantly higher ratings for physical health. The physical activity by country interaction was significant for wellbeing. MANCOVA also revealed significant differences across physical activity levels and four established age categories. Participants in the oldest category reported being significantly least affected by personal and emotional problems; youngest participants reported significantly more sleep. The age by physical activity interaction was significant for eating. Discussed in light of Hobfoll’s (1998) conservation of resources theory, findings endorse the policy of advocating physical activity as a means of generating and maintaining resources combative of stress and protective of health

The role of prediction error and memory destabilization in extinction of cued-fear within the reconsolidation window.

Extinction of a cued-fear memory within the reconsolidation window has been proposed to prevent fear reacquisition by reconsolidation interference. This ‘retrieval-extinction’ procedure has received interest for its therapeutic potential to reduce the impact of fear memories on behavior. To fully exploit its therapeutic potential, it is critical to understand the mechanisms that underlie the ‘retrieval-extinction’ effect. If the effect depends upon reconsolidation of the original memory, then it would be predicted that destabilization, induced by prediction error, would be critical for observing the effect. Here, the dependency of the retrieval-extinction effect on memory destabilization or prediction error was investigated in pavlovian cued-fear conditioned adult male rats. The requirement for memory destabilization, and thus reconsolidation, for the retrieval-extinction effect was subsequently investigated using region-specific pharmacological blockade of dopamine D1-receptors. Intra-basolateral amygdala antagonism of dopamine D1-receptors did not prevent the reacquisition of fear associated with the retrieval-extinction procedure. The requirement for prediction error was assessed by using a reinforced or non-reinforced memory retrieval trial before extinction, compared to a no-retrieval, extinction-only control. Both the reinforced (no prediction error) and non-reinforced retrieval sessions led to a decrease in fear reacquisition, suggesting that engagement of prediction error does not influence the occurrence of retrieval-extinction. Together, these data suggest that retrieval-extinction does not require memory destabilization, since behavioral or pharmacological interventions that prevent destabilization did not disrupt any capacity to attenuate fear