Psychiatry/Behavioral

~7% of blueprint

Mood, anxiety, psychotic, substance use disorders.

Disease Profiles

Region: Midbrain dopamine projections.
Key Structures: Mesolimbic, mesocortical, nigrostriatal, and tuberoinfundibular pathways.
Clinical Correlation: Mesolimbic excess → positive psychotic symptoms; nigrostriatal blockade → EPS; tuberoinfundibular blockade → hyperprolactinemia.

High-Yield Pearl

Antipsychotics help via mesolimbic blockade, but nigrostriatal blockade → EPS and tuberoinfundibular → ↑ prolactin.

Region: Hypothalamus → pituitary → adrenal cortex.
Key Structures: CRH → ACTH → cortisol, with negative feedback to the hypothalamus & pituitary.
Clinical Correlation: Chronic stress and major depression are associated with HPA overactivity and elevated cortisol.

High-Yield Pearl

Depression is linked to HPA-axis overactivity and elevated cortisol (impaired dexamethasone suppression).

Region: Medial temporal lobe & subcortical structures.
Key Structures: Amygdala (fear/emotion), hippocampus (memory), cingulate gyrus, fornix, hypothalamus.
Clinical Correlation: Amygdala hyperactivity in anxiety/PTSD; hippocampal atrophy with chronic stress, depression, and Alzheimer’s.

High-Yield Pearl

Amygdala = threat detection; hippocampus = memory consolidation — both central to PTSD.