All are true about reticular activating system except?
Ans. is 'd' i.e., Produces a-block on EEGReticular activating system (RAS) is the ascending polysynaptic pathway that extends from brainstem reticularformation to non-specific thalamic nuclei (intralarninar and midline nuclei) and projects diffusely to cerebral coex.Long sensory tracts give collateral to the RAS, as they ascend in brainstem. Thus RAS receives inputs from the medial and trigeminal leminisci as well as from the visual, auditory and olfactory systems.Therefore, the RAS is a non-specific system which can be excited by any sensation.Activation of RAS causes activation of cerebral coex and arousal from sleep.On arousal from sleep, the EEG pattern changes to high frequency low voltage activity (b - wave) from high voltage slow waves (d - waves) of sleep - d-block (not a-block).
Involved in arousal
Polysynaptic pathway
Receives collateral from all sensory pathway
Produces a-block on EEG