The glutamate hypothesis of depression states that abnormalities in glutamate activity (especially extremities) may be the underlying cause of depressive disorders as chronic stress or trauma may lead to excess glutamate release. This can lead to neurotoxicity, impaired synaptic plasticity, and structural brain changes such as dendritic atrophy in key regions like the prefrontal cortex and hippocampus. Unlike the slower effects of traditional SSRIs, glutamatergic modulators demonstrate rapid antidepressant effects due to their influence on NMDA receptor activity and synaptic signaling pathways.