‘A Vicious Cycle’

In a paper in Pharmacological Reviews, the researchers propose that low-grade inflammation affects brain chemicals and circuits that regulate motivation, leading to motivational deficits and a loss of interest or willingness to engage in usual activities, including work and play. These deficits can be reflected as anhedonia, the inability to feel pleasure—a core symptom of depression and likely the most disabling. The energy demands of inflammation require conservation of resources and thus the shutting down of certain behaviors. Low-grade inflammation can be caused by lifestyle changes such as diet and sedentary behavior. “A vicious cycle can occur where poor lifestyle habits lead to increased inflammation that, in turn, reduces the wherewithal or motivation to change those habits,” says Andrew Miller, William P. Timmie Professor of Psychiatry and Behavioral Sciences. This may be especially relevant during pandemic life, when even greater energy is required to sustain healthy eating and physical activity, says Miller, who coauthored the paper