The US and Europe are slowly recovering from the pandemic, but by the time we come to, the trauma is far from over. Not only have our families, our cities and villages and our workplaces changed, but also our brains. In fact, we are no longer the same as we were a year and a half ago, say psychologists.
Reported in winter 2020 more than 40 percent of US citizens have symptoms of anxiety or depression, twice as many as the year before. That number fell to 30 percent in June 2021 as vaccinations increased and COVID-19 cases decreased. In addition to diagnosable symptoms, many people reported some type of pandemic brain fog, forgetfulness, difficulty concentrating, and general memory problems.
In search of normality
Now the question arises: can our brain return to its normal state? And how can we help it? Every single experience can change our brain, either by helping us to create new synapses – the connections between brain cells – or by losing them. This process is known as neuroplasticity, and this is how our brains develop in childhood and adolescence. Thanks to this neuroplasticity, we continue to learn and create new memories even in adulthood, although our brains become less flexible as we age. The process is vital to learning, memory, and general brain health.
But many experiences also lead to the fact that the brain loses brain cells and synapses that one actually wanted or should preserve. For example, stress – something almost everyone experienced during the pandemic – can not only destroy existing neural connections but also stunt the growth of new synapses.
This happens, for example, because stress triggers the release of hormones, the so-called glucocorticoids – especially cortisol. In small doses, glucocorticoids help the brain and the body to react to a stressor (see “Fight or Flight”, in German: Fight-or-flight response, refers to a term used by the US physiologist Walter Cannon) by changing the heart rate, breathing, inflammatory reactions and much more in order to increase the chances of human survival. Once the stressor is gone, the hormone levels go down. With chronic stress, however, the stressor never feels completely gone, and the brain remains flooded with chemicals that attack it. In the long term, elevated glucocorticoid levels can cause changes that can lead to depression, anxiety, forgetfulness, and inattentiveness.
Another remote diagnosis
Scientists have not been able to directly study these types of physical changes in the brain during the pandemic, but they can from the many mental health surveys conducted over the past 18 months – and from what they have gathered from years of research know about stress and the brain – draw conclusions, of course.
For example, one study showed that people who experienced financial anxieties such as job loss or economic insecurity during the pandemic were more likely to develop depression. One of the brain regions most affected by chronic stress is the hippocampus – which is important for both memory and mood. Financial stress could flood the hippocampus with glucocorticoids for months, damaging cells, destroying synapses and the region will ultimately shrink permit. A smaller hippocampus is one of the hallmarks of depression.
Chronic stress can also alter the prefrontal cortex, the brain’s control center, and the amygdala, the center of fear and anxiety. Too many glucocorticoids for too long can interfere with connections both within the prefrontal cortex and between it and the amygdala. As a result, the prefrontal cortex loses its ability to control the amygdala, making the fear and anxiety center work out of control. This pattern of brain activity – that is, too much activity in the amygdala and too little communication with the prefrontal cortex – is often found in people with post-traumatic stress disorder (PTSD / PTSD), another disease that affected health care workers during the pandemic, for example came to the fore.