Reticular Formation
The reticular word means netlike. The Reticular Formation is a gathering of neurons in the core of the brain stem, surrounded by neural pathways that conduct ascending and descending nerve impulses between the brain and the spinal cord.
(The brain stem is the collection of the medulla oblongata, pons, midbrain)
It is often called the regulator of consciousness. It has a vast number of synaptic links with other parts of the brain and is continuously receiving ‘ information’ transmitted in ascending and descending tracts.
Reticular Formation Function
The Reticular Formation is involved in :
- Coordination of muscle activity
- Synchronization of activity controlled by the autonomic nervous system. e.g., cardiovascular, respiratory, and Digestive system.
- Maintainance of body balance
Reticular Activating System
The Reticular Activating System falls under the Reticular Formation.
‘Reticular Formation’ extends from the superior part of the spinal cord and upto the interbrain’s inferior (diencephalon).
The ‘Accending Pathway‘ contains sensory neurons( Carry impulses from organ to brain), and the ‘Descending Pathway‘ has motor neurons(Carries impulses from the brain to organs). This Ascending pathway, additionally named as the Reticular Activating System.
The Accending pathway includes- touch, pain, temperature, visual, auditory stimuli, mental activities.
RAS Function
- Attention,
- Arousal( Awakening from sleep),
- Produce sleep,
- Consciousness,
- Prevents sensory overload (Suppose in a crowded place, you receive lots of sensory impulses simultaneously. Here, RAS acts as a barrier. it does not allow all the impulses to travel to the brain, acting as a filter.)
If RAS gets damaged somehow, the person can go to a permanently unconscious state known as Coma.
RAS receives inputs from the eyes, ears, and other sensory receptors. But there is no input from the sense of smell. That is why a person cannot wake by the sense of smell when at sleep.
RAS sends impulses and spread it to the entire cerebral cortex.
The Descending Pathway spreads from the cerebellum to the spinal cord.
Function of the Descending Pathway
- It regulates the muscle tone,
- It controls heart rate.
- Regulates Blood pressure
- It also synchronizes the respiratory rate
Reticular Formation is responsible for every action of our day to day life. It is even known to play a role in our emotional intelligence.