EXERCISE AND THE BRAIN
Strong evidence suggests that physical activity can have a wide range of positive effects on the brain and that these effects can be immediate, long-lasting and protective. However, the optimal exercise regime required to achieve these beneficial effects as well as the specific neurochemical pathways by which exercise exerts these effects remain unclear.
To start to address these questions, research in the Suzuki lab revolves around three major themes. First, studies in the lab are attempting to define the optimal exercise “prescription” that maximally enhance learning, memory, attention, mood and academic performance in school/university settings. Second, we are exploring the kinds of exercise that maximally improve cognition in adult populations including baby boomers. Third, we are starting to ask how we can most effectively use physical exercise to improve mood and cognition in a number of different neurological conditions including traumatic brain injury (TBI), Alzheimer’s disease, Parkinson’s disease and depression. A long term goal is to understand the neural mechanisms underlying these exercise-related changes in cognitive performance across these different populations and age groups.
MEMORY AND THE BRAIN
Memory for the facts and events of our lives, referred to as “declarative” memory, defines us as individuals and helps construct our own personal histories. For many years, the major goal of the Suzuki lab was to understand how the brain allows us to lay down and retain new declarative memories. To do this, we examined the patterns of electrical activity in brain cells during the performance of various memory demanding tasks.
While the Suzuki Lab’s work on the neurophysiology of memory has ended, (all current studies in the Suzuki lab are now focused on the effects of exercise on brain functions – including on memory), our research focus for 18 exciting years was on decoding the neurophysiological responses of neurons in a structure called the hippocampus, a part of the brain known to be essential for declarative memory (memory for facts and events). A major line of inquiry in the lab examined the dynamic changes that take place in the pattern of neural activity in hippocampal cells as subjects formed new memories. Our lab was the first to identify dramatic changes in hippocampal activity as new associative memories (i.e., memory for the association between unrelated items) are formed (Wirth et al., 2003). We have also examined the patterns of neural activity that underlie memory for temporal order (i.e., what happened first, second and third), a critical component of event memory. We showed that the hippocampus provided a prominent timing/temporal ordering signal (Naya and Suzuki 2011).
We are currently analyzing studies in which we asked how the hippocampus and it’s neighboring brain areas interact with other brain regions including the prefrontal cortex, important for attention and working memory and the striatum, important for motor and reward functions.