Final answer:
GABA is the major inhibitory neurotransmitter in the CNS, and its low levels are associated with neurological issues like seizures, tremors, and insomnia. It maintains CNS stability by preventing overexcitation and is targeted in treatments for various neurological disorders.
Step-by-step explanation:
The major inhibitory neurotransmitter referred to in the question is GABA (gamma-aminobutyric acid). An undersupply of GABA can be linked to various neurological issues such as seizures, tremors, and insomnia. GABA's primary role in the central nervous system (CNS) is to prevent overexcitation, which can lead to neurotoxicity and neurological disorders. Medications and substances that inhibit the reuptake of neurotransmitters such as epinephrine and serotonin, or those that depress the CNS, often target GABA receptors to exert calming effects, alleviate anxiety, and promote sleep. Tork (1990) and Trevelyan et al. (2013) have noted that alterations in GABAergic activity are significant in conditions such as seizure propagation and neurodegenerative diseases like Alzheimer's. Additionally, an imbalance between excitatory and inhibitory neurotransmitters is a key feature in neurological disorders, including epilepsy and schizophrenia, where the neurotransmitter acetylcholine also plays a role.