Sherrington’s classic decerebrate rigidity experiments
Author: Charles Scott Sherrington
Paper:
- On the spinal animal (1897)
- Decerebrate rigidity, and reflex coordination of movements
Decerebrate Rigidity
Sherrington showed that:
· Transection of the brainstem below the red nucleus → extensor rigidity
· Reflexes become exaggerated
· Limbs show strong tonic extension to stimuli (basis of magnet reaction)
Magnet Reaction
Magnet reaction (in decerebrate rigidity)
Definition:
When a stimulus is applied to the sole of the foot, the limb shows strong
extension and seems to stick to the stimulus, as if attracted by a magnet.
How it is tested
- Examiner presses or strokes the sole
- The leg extends forcefully
- The limb may follow the stimulus → appears "magnet-like"
This happens because of:
- Hyperactive extensor reflexes
- Loss of cortical inhibition
- Overactivity of vestibulospinal pathways
Snapshot
