What is Neuroinflammation?
Neuroinflammation is the activation of the brain’s immune system, involving microglia and astrocytes that produce inflammatory molecules within the central nervous system. While protective in acute situations, chronic neuroinflammation damages neural tissue and is implicated in depression, Alzheimer’s, and other disorders.
How it works
The brain has its own immune system, distinct from the body’s peripheral immune system. Microglia (the brain’s resident immune cells) monitor for threats and, when activated, release pro-inflammatory cytokines. In acute injury or infection, this response is protective. In chronic conditions (sustained psychological stress, obesity, aging), persistent microglial activation produces low-grade neuroinflammation that damages synapses, impairs neurogenesis, and alters neurotransmitter function. This may explain the link between chronic stress and depression.
Applied example
A person experiencing chronic work stress shows elevated inflammatory markers in both blood and cerebrospinal fluid. The sustained neuroinflammation impairs hippocampal function (memory problems), reduces serotonin synthesis (depressed mood), and damages prefrontal circuits (executive dysfunction), demonstrating how psychological stress produces neurological damage.
Why it matters
Neuroinflammation is a key mechanism linking chronic psychological stress to brain dysfunction and psychiatric illness, explaining why anti-inflammatory interventions show promise for treating depression.
