| Popis: |
Numerous human imaging studies have now examined the effects of stress, depression, and cardiovascular disease (CVD) on the brain. However, few have examined these effects collectively or prospectively to identify potential links between these conditions. This chapter examines the adaptive and maladaptive changes in the brain that occur in response to stress, including the responses that lead to onset of CVD and depression. In addition, neuroimaging studies of common treatments of CVD and depression are considered in the context of ameliorating deleterious changes to the brain. A common set of structural and functional cortical alterations have been observed following exposure to stress and to the onset of both CVD and depression. This includes: (1) hyperreactivity in emotion and threat monitoring/regulation systems coupled with decreased emotional regulation (including amygdala, prefrontal cortex, and connectivity between these regions); (2) overactive error monitoring, rumination, affective and self-monitoring response systems (including anterior and posterior cingulate and insula); (3) deficits in cognitive, memory, and attention-related regions (including hippocampus, frontal, parietal, and temporal regions); and (4) a sluggishness of limbic and reward regions (including basal ganglia, striatal regions, and nucleus accumbens). These altered cortical responses can exert direct effects, wherein brain regions influence endocrine function directly, leading to dysregulated hormone production and feedback systems, or exert indirect effects by increasing engagement in risk behaviors or declining adherence to healthy behaviors. Fortunately, the structural and functional changes occurring in the brain upon exposure to stress, which can lead to manifestations of depression and/or CVD, have been shown to be malleable, and evidence is mounting that they can be restored to healthier patterns. |
