Imaging the effects of exercise on the brain

In this issue of Schizophrenia Research, Woodward et al. (2020) report on changes in cortical thickness and volume within the medial temporal lobe in people with early psychosis, following exposure to 12 weeks of either aerobic exercise or yoga practice. A longstanding body of neuroimaging research in the general population has demonstrated that physical activity can improve various aspects of ‘brain health’, with evidence from randomized trials and epidemiological studies showing beneficial effects from aerobic exercise on both cognitive functioning and neural architecture (Erickson et al., 2019). The potential for using exercise-induced neuroplasticity in the treatment of psychotic disorders has gained considerable interest since the seminal study by Pajonk et al. (2010); a proof of concept randomized controlled trial, which reported a 12% increase in hippocampal volume after 3 months of aerobic exercise in males with schizophrenia, along with significant improvements in cognitive functioning and symptoms compared to a time-and-attention matched control condition (table football). A number of subsequent studies have emerged examining neurocognitive outcomes from various types of exercise interventions for people with psychotic disorders, while seeking to identify the underlying mechanisms of beneficial cognitive effects (Firth et al., 2017). Despite the overall promising message of neurocognitive benefits from exercise in the treatment of psychotic disorders, the earlier findings by Pajonk et al. (2010) on increased hippocampal volume from aerobic training have failed to replicate in some subsequent studies (Firth et al., 2017; Malchow et al., 2016). Interestingly, a previously published study (using data from the same trial as Woodward et al. (2020)) has replicated the findings of Pajonk et al. (2010) observing significant increases in hippocampal volume from aerobic exercise (Lin et al., 2015) - only this time in females with early psychosis (whereas Pajonk et al. (2010) examined males with established schizophrenia).