White matter is parts of the brain that comprise myelinated axons, while grey matter comprises neurons bodies, axon terminals, dendrites, and synapses. Myelin that covers the white matter axons is essential for the fast transmission of electrical signals to the grey matter nerve cells, and therefore, plays a key role in learning and brain function .
Unfortunately, with aging and neurodegenerative diseases such as Alzheimer’s disease (AD), dementia, and multiple sclerosis (MS), the integrity of the white matter decreases in healthy aging populations and is significantly pronounced in patients with neurodegenerative diseases. Fortunately, the brain has also developed mechanisms to adapt to age-related changes of white matter through a process known as neuroplasticity.
Walking, Dancing, and Neuroplasticity
The capacity of the brain to make new connections in response to learning a new ability, environmental factors, physical activities, and psychological stress, is known as brain plasticity or neuroplasticity. Interestingly, a study reported the importance of the white matter in promoting neuroplasticity through physical activities, such as walking and dancing.
Using advanced imaging techniques of the brain, they showed that aerobic walking and social dance interventions result in positive changes in the white matter regions compared to widespread decreases in non-active control groups of people. They also showed a positive correlation between improvements in episodic memory performance (part of long-term memory), walking, and dancing .
Finally, the researchers also suggested that although these results are encouraging, other measures are required to better understand white matter plasticities such as neurotrophic factors and markers of inflammation and vascular function.
The study showed that walking and dancing may improve white matter plasticity, which would result in positive effects on memory in aging populations and patients with neurodegenerative diseases. Future studies with a higher number of participants and using advanced imaging techniques will certainly provide a better understanding of how the exercise-induced adaptations lead to increased episodic memory function.
 Colmenares, A.M., Voss, M.W., Fanning, J., Salerno, E.A., Gothe, N.P., Thomas, M.L., McAuley, E., Kramer, A.F., and Burzynska, A.Z., 2021. White matter plasticity in healthy older adults: the effects of aerobic exercise. NeuroImage, p.118305.