henry copeland:

Cognitive dysfunction in major depression and bipolar disorder: Assessment and treatment options - MacQueen - 2016 - Psychiatry and Clinical Neurosciences - Wiley Online Library

Exercise may have positive effects on cognition in healthy people and is being investigated as a possible strategy for maintaining cognitive function throughout aging. It also improves symptoms of depression.[76-79] The degree to which it actually improves cognitive function in those with a mood disorder is not well known.[80] High-dose exercise was associated with improvement in spatial working memory while other cognitive domains, including attention, visual memory, and spatial planning, improved regardless of dose in one study.[81] Another study included a subset of patients with BD (3/12, while the other participants had schizophrenia) and found that intense circuit training was associated with improvement in memory and processing speed; depressive symptoms also improved.[82] There are therefore a variety of factors that require investigation to understand how to maximize the benefits of exercise on cognition in patients with mood disorders. These include better understanding of the individual variability in response to training, optimal dosing or training schedules, the synergistic effects of exercise in combination with other interventions[83] and the actual mechanisms through which exercise works on the neural circuits that are disrupted in depression.
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