Fear learning and generalization during pandemic fear: How COVID-19-related anxiety affects classical fear conditioning with traumatic film clips

Far from the threatening crowd: Generalisation of conditioned threat expectancy and fear in COVID-19 lockdown

Fear and anxiety are rarely confined to specific stimuli or situations. In fear generalisation, there is a spread of fear responses elicited by physically dissimilar generalisation stimuli (GS) along a continuum between danger and safety. The current study investigated fear generalisation with a novel online task using COVID-19-relevant stimuli (i.e., busy or quiet shopping street/mall scenes) during pandemic lockdown restrictions in the United Kingdom. Participants (N = 50) first completed clinically relevant trait measures before commencing a habituation phase, where two conditioned stimuli (CSs; i.e., a busy or quiet high street/mall scene) were presented. Participants then underwent fear conditioning where one conditioned stimulus (CS+) was followed by an aversive unconditioned stimulus (US; a loud female scream accompanied by a facial photograph of a female displaying a fearful emotion) and another (CS-) was not. In a test phase, six generalisation stimuli were presented where the US was withheld, and participants provided threat expectancy and fear ratings for all stimuli. Following successful conditioning, fear generalization was observed for both threat expectancy and fear ratings. Trait worry partially predicted generalised threat expectancy and COVID-19 fear strongly predicted generalised fear. In conclusion, a generalisation gradient was evident using an online remote generalisation task with images of busy/quiet streets during the pandemic. Worry and fear of COVID-19 predicted fear generalisation.

Evaluation of the effects of pandemic-related fears on anxiety and depression: the mediating roles of traumatic stress and loneliness

BACKGROUND

The detrimental mental health effects which emerged from COVID-19 have profoundly affected healthcare workers (HCWs) worldwide. The aim of this study was to investigate the mediating effects of traumatic stress and loneliness on the fears of contracting and dying from COVID-19, and anxiety and depression of HCWs during the pandemic.

METHODS

A cross-sectional online survey was completed by HCWs in a province of Turkey. The Hospital Anxiety Depression Scale, Impact of Events Scale-Revised and numerical rating scales (for fears of COVID-19 and loneliness) were used and a bootstrap approach was used in the analyses with SPSS PROCESS macro software.

RESULTS

Of the HCWs evaluated, 150 (34.4%) were doctors, with a mean duration of work experience of 10.6 ± 7.5 years. The results indicated that fear of contracting COVID-19 was directly related to anxiety (β = 0.244, p < 0.001) and depression (β = 0.135, p < 0.01) and that traumatic stress and loneliness mediated the relationships between the fear of contracting COVID-19 and anxiety (β = 0.435, p < 0.001; β = 0.235, p < 0.001, respectively) and depression (β = 0.365, p < 0.001; β = 0.294, p < 0.001, respectively). The fear of dying from COVID-19 was determined to be directly associated with anxiety (β = 0.190, p < 0.001) but not with depression (β = 0.066, p = 0.116), and traumatic stress and loneliness mediated the relationships between the fear of dying from COVID-19 and anxiety (β = 0.476, p < 0.001; β = 0.259, p < 0.001, respectively) and depression (β = 0.400, p < 0.001; β = 0.311, p < 0.001, respectively).

CONCLUSIONS

The study results demonstrated the important roles of traumatic stress and loneliness in exacerbating the negative consequences of fears of COVID-19 on anxiety and depression, and provide insights for identifying HCWs at greater risk.

The challenges of mental health in Chilean university students

Mental health is a crucial issue in Chile and worldwide, gaining even more relevance following social events in Chile in 2019, including the sociopolitical crisis and the COVID-19 pandemic. In Chile, over 20% of adolescents experience mental health problems such as anxiety, depression, and stress, with many going untreated due to limited access or the stigma associated with these issues. The COVID-19 pandemic has exacerbated this situation, with a 25% increase in the prevalence of anxiety and depression. The university population is particularly vulnerable to mental health challenges due to the unique pressures of the academic environment, including increased academic demands and the acquisition of university-related behaviors that can negatively impact physical and mental health, with notable gender differences. Effectively addressing these issues is essential for ensuring the emotional and psychological well-being of university students. Specific policies and programs are needed to address the mental health needs of university adolescents and ensure that they have access to mental health services required to navigate the challenges of daily life. A methodology reflective of the essayistic approach guides this exploration, which is characterized by critical reflection and structured argumentation.

Familiar observers attenuate surgery-induced neuroinflammation and cognitive dysfunction in mice

AIMS

Postoperative cognitive dysfunction (POCD) is a common complication associated with poor outcome. Our previous study has shown that living with familiar observers in the same cage reduces anxiety of mice with surgery. Anxiety can impair learning and memory. Thus, this study was designed to determine whether living with familiar observers attenuated the dysfunction of learning and memory of mice with surgery.

METHODS

Six- to eight-week-old CD-1 male mice or 18-month-old C57BL/6 male mice had left carotid artery exposure under isoflurane anesthesia. They lived with non-surgery male mice at 2 (number of surgery mice) to 3 (number of non-surgery mice) ratio or with other surgery mice. Mice were subjected to light and dark box test 3 days after surgery to measure their anxiety levels and novel object recognition and fear conditioning tests from 5 days after surgery to measure their learning and memory. Blood and brain were harvested for biochemical analysis.

RESULTS

Living with familiar observers that lived with surgery mice for at least 2 weeks before the surgery and then after surgery reduced the anxiety and dysfunction of learning and memory in young adult male mice. Living with unfamiliar observers that lived with surgery mice after the surgery but not before the surgery did not have those effects on the mice with surgery. Living with familiar observers attenuated learning and memory dysfunction after surgery also in old male mice. Living with familiar observers attenuated inflammatory response in the blood and brain and the activation of the lateral habenula (LHb)-ventral tegmental area (VTA) neural circuitry, which has been shown to be important for POCD. Wound infiltration with bupivacaine attenuated the activation of LHb-VTA.

CONCLUSION

These results suggest that living with familiar observers attenuates POCD and neuroinflammation, possibly via inhibiting the activation of the LHb-VTA neural circuitry.

Changes in fear-associated learning task brain activation over the COVID-19 pandemic period: a preliminary longitudinal analysis

Background

The COVID-19 pandemic has had profound impacts on people worldwide. Previous studies have shown that fear learning, extinction, recall, and contextual information processing involve the activation of emotion and sensory brain systems, which can be modified. However, it remains unclear whether brain functions associated with these processes have been altered over the pandemic period.

Methods

We compared pre- and peri-pandemic brain activation during a fear-associated learning task (FALT) using previously collected data. The participants were divided into two groups: the pandemic group (n = 16), who completed a baseline FALT before the pandemic and repeated the task during the pandemic, and the non-pandemic group (n = 77), who completed both sessions before the pandemic began.

Results

Compared with the non-pandemic group, the pandemic group exhibited significant decreases in brain activation from baseline to follow-up assessments, including activation in the brainstem during early fear learning, the posterior thalamus/hippocampus during late extinction, and the occipital pole during late recall phases for contextual processing. Furthermore, activations associated with retrieving safety cues were reduced in the posterior cingulate, premotor, and calcarine cortices during the early recall phase, and activations associated with retrieving dangerous cues decreased in the occipital pole during the late recall phase. Additionally, correlations between decreased activation and elevated posttraumatic stress symptoms were observed.

Conclusion

These findings suggest that activations associated with processing low arousal contextual information, safety cues, and extinguished fear cues decreased during the pandemic. These changes in brain activation may have contributed to the increase in mental health disturbances observed during this time.

The next frontier: Moving human fear conditioning research online

Fear conditioning is a significant area of research that has featured prominently among the topics published in Biological Psychology over the last 50 years. This work has greatly contributed to our understanding of human anxiety and stressor-related disorders. While mainly conducted in the laboratory, recently, there have been initial attempts to conduct fear conditioning experiments online, with around 10 studies published on the subject, primarily in the last two years. These studies have demonstrated the potential of online fear conditioning research, although challenges to ensure that this research meets the same methodological standards as in-person experimentation remain, despite recent progress. We expect that in the coming years new outcome measures will become available online including the measurement of eye-tracking, pupillometry and probe reaction time and that compliance monitoring will be improved. This exciting new approach opens new possibilities for large-scale data collection among hard-to-reach populations and has the potential to transform the future of fear conditioning research.