Gate Control Theory (Melzack 1965) pain theory

Melzack in 1965

Who invented the gate control theory and when?

That pain is detected and picked up by sensory signals (pathways), and that the spinal chord plays a key role in us feeling pain.

What was the idea proposed by Melzack?

The spinal chord acts as the gate. If the cells were 'open' the message would flow to the brain and pain would be consciously felt. If the gate was 'closed' it would not be felt. We can tell if the 'gate' is open or closed by whether we feel pain or not.

What job did the spinal chord have in the gate control theory?

The amount of activity in pain fibres.

The amount of activity in peripheral fibres.

Messages from the brain (feelings)

What are the free factors that control the gate?

They are fibres nearby and are called A-beta fibres.

What are peripheral fibres and what are they called?

It means that if something is more painful the gate is more likely to be opened. Pain is more likely to be felt by a higher activation of the pain fibres. E.g. paper cut or chopped finger off. More fibres are activated by the chopped finger.

What does the amount of activity in pain fibres mean?

Whether someone is anxious or excited can affect how much the hate is open or closed. So anxiety might open the gate more or excitement could keep the gate more shut and harder to open as it is a distraction

What do they mean by messages from the brain can affect the gate?

Severe injuries such as broken limbs.

Anxiety, worry or depression (psychological)

Focusing on the pain, not being distracted away from the pain can open the gate more.

Small pains open the gate, but then when distracted it goes away. It will only come back when irritated, for example paper cut and if later it gets in contact with lemon juice.

What are some examples that may open the gate?

Distraction from the pain.

Positive emotions of relaxation and rest.

Medication.

What are some examples that may close the gate?