Which neurotransmitter is primarily responsible for the excitation of brain activity?

Glutamate is primarily responsible for the excitation of brain activity because it is the main excitatory neurotransmitter in the central nervous system. It plays a crucial role in synaptic transmission, affecting various cognitive functions such as learning and memory. When glutamate binds to its receptors, it leads to the depolarization of neurons, promoting the firing of action potentials. This excitatory action contrasts with that of other neurotransmitters, such as GABA, which is primarily inhibitory and reduces neuronal excitability. By facilitating communication between neurons, glutamate is vital for maintaining proper brain function and is involved in important processes such as neural plasticity, which is essential for learning and memory formation.