What is the primary function of GABA in the human brain?

GABA, or gamma-aminobutyric acid, is the primary inhibitory neurotransmitter in the central nervous system. Its main function is to reduce neuronal excitability throughout the nervous system, which promotes a calming effect. This inhibitory action is essential for maintaining the balance between excitation and inhibition in the brain, which plays a critical role in regulating mood, anxiety, and sleep.

By promoting relaxation and sleep, GABA facilitates the transition to rest and helps manage stress responses. This neurotransmitter is involved in processes that allow the brain to calm down, leading to decreased levels of anxiety and improved quality of sleep. Medications that enhance GABA activity, such as benzodiazepines, are commonly used to treat anxiety disorders and sleep disturbances, further illustrating its role in promoting relaxation.

The other functions highlighted in the incorrect options do not accurately reflect GABA’s role. While enhancing neuroexcitability, increasing anxiety levels, or raising alertness and focus may pertain to other neurotransmitters such as glutamate (which increases excitation), norepinephrine, or dopamine, they do not apply to the primary function of GABA.