Dysfunction in NSD neurotransmitter systems may cause agitated behaviors1-4
An underlying cause of Agitation in Alzheimer's Dementia (AAD) may be due to dysfunction in the norepinephrine, serotonin, and dopamine (NSD) neurotransmitter systems, which may result in an imbalance between top-down executive function and bottom-up emotional drive.
Norepinephrine system hyperactivity, serotonin system deficits, and dopamine system dysregulation may be associated with agitated behaviors.3-14
Norepinephrine system hyperactivity may promote an increase in emotional response in AAD3,5-8
AAD may be associated with elevated norepinephrine signaling. This may result in heightened emotional drive from the amygdala to the prefrontal cortex.3,5-8
Serotonin system deficits impair top-down executive function4,9,10
Serotonin normally helps facilitate top-down executive function and appropriate behavior. However, a decrease in serotonin signaling in AAD may lead to increased aggression and impulsivity.4,9,10
Dopamine system dysregulation affects agitated and aggressive behaviors4,11-14
As serotonin is an important regulator of dopamine activity, serotonin deficits may lead to dopamine dysregulation. The increase in dopamine activity is implicated in agitated and aggressive behaviors.4,11-14
AAD, Agitation in Alzheimer's Dementia; NSD, norepinephrine, serotonin, and dopamine; PFC, prefrontal cortex.
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