Fig. 8

Neurons and Effects of Stress. Chronic stress in increasing amounts and frequency will cause a biphasic curve reflecting negative remodeling of dendrites and synaptic connections in many brain regions, including hippocampus, amygdala, medial prefrontal and orbitofrontal cortex (upper section). Such effects of acute and chronic stress operate in space and time in an inverted U-shaped manner (lower section). Acute stress, mediated by glucocorticoids, excitatory amino acids and other mediators can enhance excitability and promote memory over minutes to hours as long as the stressor is not overly intense; intense stress can have the opposite effect. Chronic stress causes neuronal remodeling as depicted in the upper section. This is usually largely reversible, as toxic stress subsides, promoting adaptation. Yet, if there is no reversal of the stress-induced changes in neuronal architecture, chronic stress-related NCDs have a better chance of emerging. From; McEwen et al, 2016, p. 13, [110]. "Reprinted from Neuropsychopharmacology Reviews 2016; 41, 3–23. McEwen BS, Nasca C, Gray JD. Stress Effects on Neuronal Structure: Hippocampus, Amygdala, and Prefrontal Cortex. P. 13 with permission from Springer Nature via STM guidelines"