How COVID-19 and Parkinson’s Research Reveal the Brain’s Hidden Vulnerability

 The human brain is remarkably adaptable which has allowed us to get where we are now, however it is also surprisingly fragile. In a recent National Geographic article Can Covid-19 alter your personality? Here's what brain research shows by Sharon Guynup, scientists explored how COVID-19 may alter the brain in ways that subtly change mood, behavior, or even personality. Neuroimaging studies show that infection can cause loss of gray matter and disrupt networks responsible for memory and emotion, leading to “brain fog,” anxiety, and fatigue. These effects display the neurological decline seen in diseases like Parkinson’s, raising an unsettling possibility, a viral infection might temporarily or even permanently rewire the circuits that make us who we are. This research reminds us that personality and cognition aren’t fixed, they rely on sensitive biochemical and neural balances that illness can disrupt within us.

Meanwhile, the Global Parkinson’s Genetics Program (GP2), featured in The American Journal of Human Genetics (2025), approaches the same issue, how brains change through the lens of genetics. The project unites scientists across more than 60 countries to identify gene variants that influence susceptibility to Parkinson’s disease and its diverse symptoms. While COVID-19 represents an external attack on the brain, GP2 focuses on internal predispositions. For example, how inherited differences in genes like LRRK2 or SNCA might determine who develops neurodegeneration and how it progresses. Both cases emphasize the importance of diversity and data sharing in neuroscience. Essentially to understand the brain fully, we must study it across populations, ages, and environmental contexts.

Together, these findings reveal that neurological health is a conversation between genes and environment. Viral inflammation, as seen with COVID-19, might act as a trigger for neural damage in those already genetically predisposed to disorders like Parkinson’s. Projects like GP2 give scientists the tools to identify those vulnerabilities before disease appears. Whereas studies of infection show how everyday exposures can tip the balance. Ultimately, both areas of research remind us that protecting the brain requires more than treating symptoms. It demands a deeper understanding of how biology, environment, and experience interact to shape the mind itself.