Psychology MCAT Practice Exam

Neurotransmitters play a crucial role in the nervous system by transmitting signals across synapses, which are the junctions between neurons. When an electrical impulse, known as an action potential, reaches the end of a neuron (the presynaptic neuron), it triggers the release of neurotransmitters from vesicles into the synaptic cleft—the small gap between neurons. These neurotransmitters then bind to specific receptors on the surface of the neighboring neuron (the postsynaptic neuron), which can lead to the initiation of a new electrical signal in that neuron if the signal is strong enough.

This process is fundamental for communication within the nervous system, as it allows for the propagation of signals that coordinate various functions, from muscle contraction to mood regulation. Additionally, neurotransmitters can have excitatory or inhibitory effects, influencing how neurons communicate and the overall activity in the neural circuits.

In contrast, blocking signals between neurons does not accurately represent the function of neurotransmitters; rather, they facilitate communication. The idea that neurotransmitters only enhance physical abilities is overly simplistic and doesn't encompass their widespread influence on many aspects of brain function, mood, cognition, and behavior. Furthermore, while neurotransmitters are involved in neural signaling, they do not regulate the