Coupon Accepted Successfully!


Reticular formation

It is a network of nerve cells and fibers in the central core of the brainstem (It is present in the mid ventral portion of the medulla, pons and midbrain). It is a complex poly-synaptic pathway and has many of the important centers in the medulla viz deglutition center , vomiting center , respiratory center , center for cardiovascular regulation.




A.    Afferents

  • Collaterals from the specific sensory pathways (ascending sensory tracts)
  • Cerebral cortex (corticofugal fibres)
  • Cerebellum
  • Basal ganglia

from reticular formation

  • Ascending pathway – the ascending reticular activating system (ARAS) to the cerebral cortex (via the thalamus – cf thalamus)
  • Descending pathway- the reticulo spinal tract


B.        Functions of the reticular system

Maintenance of sleep / wakefulness cycle: stimulation of ARAS causes arousal, awakefulness and alertness

Modulation of muscle tone:

  • Reticular formation is one of the supraspinal influences for the stretch reflex (e.f. regulation of posture) it is the location of all the vital centers as mentioned above


  1. it is concerned with synchronization / desynchronisation of E.E.G waves
  2. stimulation of reticular formation : desynchronisation of EEG
  3. inhibition of reticular formation : synchronization of EEG
  4. Sensation
  5. it modulates / controls sensory input to CNS eg supraspinal control of pain (gate control theory of pain)
  6. it modulates sensory impulses of muscle spindle
  7. it has role in focusing of attention (selective attention ) probably by cutting off all other signals
  8. It is necessary for learning and conditioned reflex.

Test Your Skills Now!
Take a Quiz now
Reviewer Name