Involuntary actions and the medulla

The idea

Involuntary actions, which we cannot control by thinking, are controlled by the mid-brain and hind-brain; the medulla in the hind-brain controls blood pressure, salivation and vomiting.

Mouth watering

Your mouth waters when you see your favourite food. You did not decide to make it happen, and it is hard to stop it by thinking.

Which part of the brain do you think helps control such actions?

• The mid-brain and hind-brain
• The motor areas of the fore-brain
• The bony box around the brain

Sort the actions

Sort each action into the right group.

Beyond thinking

Between simple reflexes and thought-out actions there is a third set. We cannot control it easily by thinking about it. The medulla, a part of the hind-brain, runs several of these.

Involuntary actions, which we cannot control by thinking, are controlled by the mid-brain and hind-brain. The medulla in the hind-brain controls blood pressure, salivation and vomiting.

Notes

Involuntary actions, which we cannot control by thinking, are controlled by the mid-brain and hind-brain; the medulla in the hind-brain controls blood pressure, salivation and vomiting.

Check yourself

Which part of the hind-brain controls blood pressure, salivation and vomiting?

Which parts of the brain control many involuntary actions?

Which of these is an involuntary action?

What is true of involuntary actions?

• The cerebellum. The cerebellum is responsible for the precision of voluntary actions and for posture and balance.
• The motor area. Motor areas are in the fore-brain and control voluntary muscles.
• The medulla — correct. Yes!
• The mid-brain and the hind-brain — correct. Yes!
• The fore-brain and the spinal cord. Many involuntary actions are controlled by the mid-brain and hind-brain.
• Only the motor areas of the fore-brain. Motor areas control voluntary muscles. Involuntary actions are controlled by the mid-brain and hind-brain.
• Writing. We decide what to write, so writing is voluntary.
• Salivation — correct. Yes!
• Moving a chair. We decide to move a chair, so it is voluntary.
• We decide each one before it happens. That describes voluntary actions. Involuntary actions are not controlled by thinking.
• They are controlled by the motor areas of the fore-brain. Involuntary actions are controlled by the mid-brain and hind-brain.
• We cannot easily control them by thinking — correct. Yes!