Neurotransmitters are chemicals that are released at synapses of neurons. Different neurones affect behaviours and moods. Inbalances can lead to disorders.
There are several different types of neurotransmitters released by different neurons, and we can speak in broad terms about the kinds of functions associated with various neurotransmitters. Different neurotransmitters are associated with different behaviours and actions. For example, acetylcholine is the majority neurotransmitter in many synapses of the body. It can lead to arousal and cognition as opposed to the use of dopamine as a neurotransmitter which can increase pleasure receptors and also suppress appetite. The table below summarises key neurotransmitters and how they affect behaviour.
Neurotransmitters exert their actions by binding specific receptors in the brain and body, and may exert different cellular actions depending on the receptor that they bind. For example, the activating neurotransmitter glutamate can bind receptors that then allow ions to pass through the membrane (NMDA receptors), and it can also bind receptors that initiate cell signaling cascades.
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Key Points
• Neurotransmitters are chemicals that are released at synapses of neurons. Different neurones affect behaviours and moods. Inbalances can lead to disorders.
Key Terms
• Neurotransmitters: a chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and, by diffusing across the synapse or junction, causes the transfer of the impulse to another nerve fiber, a muscle fiber, or some other structure
• Acetylcholine: a chemical message released by nerve cells to send signals to other cells
• NMDA Receptor: receptor for the activating neurotransmitter glutamate