<prompt> Arousal response in mediated by:Dorsal columnReticulo activating systemSpinothalamic tractVestibule cerebellar tract  <response>: Ans. B. Reticulo activating system RAS Reticulo-Activating system:a. RAS fibers convey impulses upwards to the thalamus and cerebral cortex.b. RAS fibers are multisynaptic path beginning at the medulla and pass upward via pons and mid brain to reach the thalamus.c. Function of RAS when the RAS is stimulated, there is wakefulness and alertness of the subject and the subject becomes fully conscious. 