Persistent Depressive Disorder Persistent Depressive Disorder Neurobiology & Etiology

Question 1

Which neurotransmitter system is most commonly implicated in the pathophysiology of persistent depressive disorder?

Accepted Answer

Serotonin

Answer

Serotonergic system dysfunction is the most consistently identified neurotransmitter abnormality in PDD, which is why SSRIs are a primary pharmacological treatment.

Question 2

Which neuroendocrine axis shows chronic dysregulation in persistent depressive disorder, resulting in elevated basal cortisol?

Accepted Answer

Hypothalamic-pituitary-adrenal (HPA) axis

Answer

Chronic HPA axis hyperactivity leads to elevated cortisol, which damages hippocampal neurons and perpetuates mood dysregulation in PDD.

Question 3

Which brain structure consistently shows reduced volume on neuroimaging in patients with persistent depressive disorder?

Accepted Answer

Hippocampus

Answer

The hippocampus shows volume reduction in PDD due to chronic glucocorticoid exposure suppressing neurogenesis and causing dendritic atrophy.

Question 4

What is the estimated heritability of persistent depressive disorder (dysthymia)?

Accepted Answer

35–45%

Answer

Twin and family studies estimate the heritability of persistent depressive disorder at approximately 35–45%, indicating a moderate but significant genetic contribution.

Question 5

Which inflammatory markers have been consistently found elevated in individuals with persistent depressive disorder?

Accepted Answer

Pro-inflammatory cytokines such as IL-6 and TNF-α

Answer

Elevated pro-inflammatory cytokines like IL-6 and TNF-α are found in PDD and can cross the blood-brain barrier to affect neurotransmitter metabolism and neuroplasticity.

Persistent Depressive Disorder Practice Test

Persistent Depressive Disorder Practice Test

Persistent Depressive Disorder Persistent Depressive Disorder Neurobiology & Etiology