Actions that donot require thinking and occour without the concious choice of an organism are known as involuntary actions.
Reflex actions are a part of involuntary action as these actions occur rapidly as a responce to the external stimulus and are known as reflex involuntary actions.
- Simple reflex actions like change in the size of the pupil, and the thought out actions such as moving a chair, there is another set of muscle movements over which we do not have any thinking control.
- Many of these involuntary actions are controlled by the mid-brain and hind-brain.
- All the involuntary actions including blood pressure, salivation and vomiting are controlled by the medulla in the hind-brain.