How does the brain communicate?
The brain is a communications centre consisting of billions of neurons, or nerve cells. Networks of neurons pass messages back and forth to different structures within the brain, the spinal column, and the peripheral nervous system. These nerve networks coordinate and regulate everything we feel, think, and do.
- Neuron to Neuron
Each nerve cell in the brain sends and receives messages in the form of electrical impulses. Once a cell receives and processes a message, it sends it on to other neurons.
- Neurotransmitters – The Brain’s Chemical Messengers
The messages are carried between neurons by chemicals called neurotransmitters. (They transmit messages between neurons.)
- Receptors – The Brain’s Chemical Receivers
The neurotransmitter attaches to a specialized site on the receiving cell called a receptor. A neurotransmitter and its receptor operate like a “key and lock,” an exquisitely specific mechanism that ensures that each receptor will forward the appropriate message only after interacting with the right kind of neurotransmitter.
- Transporters – The Brain’s Chemical Recyclers
Located on the cell that releases the neurotransmitter, transporters recycle these neurotransmitters (i.e., bringing them back into the cell that released them), thereby shutting off the signal between neurons.
To send a message a brain cell releases a chemical (neurotransmitter) into the space separating two cells called the synapse. The neurotransmitter crosses the synapse and attaches to proteins (receptors) on the receiving brain cell. This causes changes in the receiving brain cell and the message is delivered.
Most drugs of abuse target the brain’s reward system by flooding the circuit with dopamine.