Välittäjäaineella

Välittäjäaineella is a Finnish term that translates to "neurotransmitter" in English. Neurotransmitters are chemical messengers that transmit signals across a chemical synapse, such as a neuromuscular junction, from one neuron (nerve cell) to another, or to a non-neuronal target cell.

These chemical substances play a crucial role in communication within the nervous system. When an electrical impulse reaches the end of a neuron, it triggers the release of neurotransmitters into the synaptic cleft, the small gap between neurons. These neurotransmitters then bind to specific receptors on the surface of the adjacent neuron or target cell, initiating a response. This response can be either excitatory, increasing the likelihood of the target cell firing an electrical impulse, or inhibitory, decreasing the likelihood.

There are numerous types of neurotransmitters, each with distinct functions and distributions in the brain and body. Examples include acetylcholine, which is involved in muscle contraction and learning; dopamine, associated with reward, motivation, and motor control; serotonin, which influences mood, sleep, and appetite; and norepinephrine, which plays a role in alertness and the stress response. The precise balance and function of these chemical messengers are vital for a wide range of physiological and psychological processes, including movement, sensation, cognition, emotion, and behavior. Dysregulation of neurotransmitter systems is implicated in various neurological and psychiatric disorders.