Sleep is a fundamental need for general health. As a PMHNP it is important to understanding the underlying causes of insomnia. Using the options below identify the neurological abnormalities associated with insomnia. (Select all that applies).

A. Decreased GABA levels in occipital and anterior cingulate cortices: GABA is the primary inhibitory neurotransmitter in the brain and promotes sleep by reducing cortical excitability. Lower GABA levels in these brain regions are linked to hyperarousal and difficulty initiating or maintaining sleep in insomnia. B. Reduced nocturnal melatonin secretion: Melatonin regulates the sleep-wake cycle through circadian rhythm modulation. Decreased secretion at night leads to delayed sleep onset and fragmented sleep patterns characteristic of insomnia. C. Decreased serum BDNF: Brain-derived neurotrophic factor (BDNF) supports neuronal plasticity and stress regulation. Low BDNF levels are associated with impaired sleep regulation and increased vulnerability to stress-related insomnia. D. Decreased glucose metabolism: While alterations in glucose metabolism can occur with sleep deprivation, it is not a defining neurological abnormality of insomnia. The core dysfunctions involve neurotransmitter imbalance and circadian rhythm disruption rather than direct metabolic decline.