Psychology - Neurons

Neurons are nerve cells that send electrical or chemical signals to communiate to eachother. These cells are specialised to receive, transmit and process information.

The cell body contains the cell’s nucleus and other standard cell components. The nucleus is the control centre for the cell and contains DNA.

The dendrite branch out from the cell body and receive messages from other nerve cells.

The axon carries nerve impulses in one direction away from the cell body.

Myelin sheath is an insulating layer that protects and speeds up the transmission of the electrical signal. Schwann cells are tissue cells responsible for creating myelin sheath.

Node of Ranvier are the gaps in myelin. These speed up transmission as signals jump via these gaps along the axon. They also keep the neuron healthy, as waste and nutrients can be exchanged through these gaps.

The axon terminal sends messages to the next neuron The axon terminal connects to the next neuron’s dendrites.

Sensory neurons detect and respond to external stimuli such as light, sound, smell etc. Depending on its location, each sensory neuron is specialised to detect certain stimuli. They then transmit the message to the CNS where the brain can process information and respond if necessary.

After the sensory neurons detect stimuli and send that information to the brain, to respond, the brain needs to send instructions back to the body. Motor neurons carry motor signals from the brain to the rest of the body. This causes a response.

Interneurons are primarily located in the spinal cord. They directly connect motor neurons and sensory neurons. They are essential for reflex actions.