Emerging adulthood is a life period of identity exploration that is experienced by the majority of emerging adults as stressful. Black emerging adults have the added burden of racism-related chronic stress. Chronic stress and cardiorespiratory fitness affect the medial temporal hippocampal (MTH) system in opposite ways. The MTH system is critical for forming new memories and for processing emotions. Although it is well-known that chronic stress has a negative impact on the MTH system, whereas cardiorespiratory fitness and exercise have a positive impact on this brain system, we don't know whether and how cardiorespiratory fitness can protect against the negative impact of chronic stress in emerging adults.
Through a five-year, $4 million R01 grant from the National Institutes of Health, Karin Schon, PhD, assistant professor of anatomy & neurobiology at Boston University School of Medicine (BUSM), plans to examine how cardiorespiratory fitness and chronic psychosocial stress interact to affect the MTH system of the brain in Black emerging adults who are exposed to daily social stress, examined through the lens of racism-rated chronic stress.
She will test the hypothesis that greater racism burden will correlate with poorer MTH system function and greater allostatic load (the cumulative burden of chronic stress and life events), whereas higher cardiorespiratory fitness will correlate with better MTH system function and greater serum Brain Derived Neurotrophic Factor (BDNF) and lower allostatic load in Black emerging adults.
"We will measure cardiorespiratory fitness using a treadmill test and serum BDNF using blood samples, both of which are known to affect the MTH system positively. We will measure racism burden across multiple dimensions, including, but not limited to interpersonal experiences of discrimination. These additional measures also capture structural and cultural forms of racism. Our goal is to examine whether greater racism burden will be associated with increased allostatic load, the physiological 'wear and tear' response to chronic stress across multiple biological systems, and whether it negatively affects the MTH system, measured with functional and structural MRI and a cognitive task designed to examine MTH function. Cardiorespiratory fitness and BDNF may buffer against the negative effects of racism burden on the MTH system by reducing allostatic load," explains Schon.
According to Schon, whether allostatic load is associated with MTH system function is unclear, but critical for understanding the role of the MTH system in mental and brain health.
Schon, received a joint BA/MA degree in psychology from the University of Hamburg in Germany in 1998 and her PhD from the department of psychological and brain sciences at Boston University in 2005. Her dissertation focused on functional neuroimaging studies of working memory and long-term (episodic) memory formation. In 2010, she received a Pathway to Independence Career Development award from the National Institute on Aging to investigate the effects of cardio-respiratory fitness and exercise on the function and structure of the medial temporal hippocampal memory system. In 2013, she joined BUSM's department of anatomy & neurobiology where she is the Director of the Brain Plasticity and Neuroimaging Laboratory.
Her brain plasticity research focuses on modulators of the MTH system across the lifespan. Currently, she is investigating the role of aerobic exercise, aging and chronic psychosocial stress, as modulators of cognitive function and brain health in aging and AD. With her cognitive neuroscience research on chronic psychosocial stress she aims to take an anti-racist perspective by focusing on the impact of interpersonal and structural/institutional racism on brain health in Black adults. The long-term goal of this research is to contribute to health policy change from a cognitive neuroscience perspective with the goal to eliminate brain health inequities.
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