Asleepy driver rounds a bend and sees a deer standing in the road. the driver snaps to attention and applies the brakes, averting the accident, because his brain was aroused by the

A sleepy driver rounds a bend and sees a deer standing in the road. The driver snaps to attention and applies the brakes, averting the accident, because his brain was aroused by the Reticular Activating system(RAS).

Explanation:

Reticular activating system (RAS) is a part of brain that filters the sensory signal that tries to reach our brain.However the olfactory Signal do not pass through it .Reticular activating system is located at the brain stem little above the spinal column.This is an extremely important part of the brain because it sorts various sensory signals into important and non-important ones.RAS allows only those information into the brain that needs immediate attention of the conscious mind.Hence it is responsible for sudden wakefulness.Our sensory organs perceive thousands of information each second and direct them towards the brain.If RAS was not there then our brain would have reached a state of confusion every minute and might have failed to give proper response to any of the stimulus.In the given situation, the sudden sight of the deer acted as a threatening stimulus.This information needed immediate attention of the driver's conscious mind and his brain was thus aroused by the RAS.