The mental consequences of the COVID-19 pandemic and the strict lockdown measures implemented by governments world-wide to fight it are currently unknown. We performed an online survey study in Switzerland and analyzed data acquired during confinement (wave 1) and during partial lifting of measures (partial deconfinement) (wave 2). Wave 1: Data from over 10’000 individuals living in Switzerland were collected between April 6 and 8, 2020, starting 3 weeks after the beginning of confinement. While 24.4% of the participants reported no change in stress levels, 49.6% of the participants reported an increase in stress levels during confinement as compared to the time before the COVID-19 pandemic. We identified several potential sources for people feeling more stressed during confinement, such as the burden related to changes at work or school, problems with childcare or not being able to spend more time with others. The changes in stress levels were highly correlated with changes in depressive symptoms. 57% of the participants reported an increase in depressive symptoms. Further, the prevalence of moderately severe or severe depressive symptoms (PHQ-9 score ≥ 15) increased from 3.4% before the COVID-19 pandemic to 9.1% during confinement. Interestingly, 26% of participants showed a decrease in stress level during confinement, suggesting that for those individuals the confinement involved a reduction of stressors and/or resulted in more time for recovery. Finally, we identified several behaviors amenable to change that were related to a reduced increase in stress level and depressive symptoms during confinement. Wave 2: Data from over 10’000 individuals living in Switzerland were collected between May 11 and June 1, 2020 during partial deconfinement. As for wave 1, we observed diverse reactions with regard to stress levels: While 28% of the participants reported no change in stress levels, 40% of the participants reported an increase in stress levels during partial deconfinement as compared to the time before the COVID-19 pandemic. We identified similar sources for people feeling more stressed as during confinement and the changes in stress levels were highly correlated with changes in depressive symptoms. 49.5% of the participants reported an increase in depressive symptoms. Further, the prevalence of moderately severe or severe depressive symptoms (PHQ-9 score ≥ 15) remained elevated with a prevalence rate of 11.7%. With regard to changeable behaviors during the pandemic, we found (as in wave 1) that spending more time pursuing new projects, spending more time pursuing hobbies at home, and light physical exercise were related to less stress increase.A comparison between the two waves indicated that while the waves did not substantially differ in the distributions of changes in stress levels or depressive symptoms, they did differ with regard to the distribution of anxiety ratings. Specifically, anxiety levels decreased from wave 1 to wave 2. Finally, we identified risk and resilience factors with regard to the development of depressive symptoms (present in both waves): A history of a prior psychiatric disorder was a risk factor for developing moderately severe or severe depressive symptoms during the pandemic. In a resilient group of people who had none or only minimal depressive symptoms before and during the pandemic, older people (≥ 55 years), men and individuals with no history of prior psychiatric disorder were overrepresented. Thus, advanced age, male gender and the absence of prior psychiatric disorder were identified as resilience factors.

Only a small proportion of what we see can later be recalled. Up to date it is unknown in how far differences in visual exploration during encoding affect the strength of episodic memories. Here, we identified individual gaze characteristics by analyzing eye tracking data in a picture encoding task performed by 967 healthy subjects during fMRI. We found a positive correlation between fixation frequency during visual exploration and subsequent free recall performance. Brain imaging results showed a positive correlation of fixation frequency with activations in regions related to vision and memory, including the medial temporal lobe. To investigate if higher fixation frequency is causally linked to better memory, we experimentally manipulated visual exploration patterns in an independent population of 64 subjects. Doubling the number of fixations within a given exploration time increased subsequent free recall performance by 19%. Our findings provide evidence for a causal relationship between fixation frequency and episodic memory for visual information.

No abstract

The amygdala is critically involved in emotional processing, including fear responses, and shows hyperactivity in anxiety disorders. Previous research in healthy participants has indicated that amygdala activity is down-regulated by cognitively demanding tasks that engage the PFC. It is unknown, however, if such an acute down-regulation of amygdala activity might correlate with reduced fear in anxious participants. In an fMRI study of 43 participants (11 men) with fear of snakes, we found reduced amygdala activity when visual stimuli were processed under high cognitive load, irrespective of whether the stimuli were of neutral or phobic content. Furthermore, dynamic causal modeling revealed that this general reduction in amygdala activity was partially mediated by a load-dependent increase in dorsolateral PFC activity. Importantly, high cognitive load also resulted in an acute decrease in perceived phobic fear while viewing the fearful stimuli. In conclusion, our data indicate that a cognitively demanding task results in a top–down regulation of amygdala activity and an acute reduction of fear in phobic participants. These findings may inspire the development of novel psychological intervention approaches aimed at reducing fear in anxiety disorders.

No abstract