<prompt> What is proposed mechanism of dissociative anesthesia effect of ketamine:-Inhibition of thalmocoical pathwayStimulation of limbic systemBothNone  <response>: Ketamine produces dissociative anesthesia which is characterized by a state wherein the patient is conscious eg., eye opening, swallowing, muscle contracture but unable to process or respond to sensory input. It acts as an antagonist at the phencyclidine site of the NMDA receptor. Ketamine functionally dissociates the thalamus which relays sensory impulses from the reticular activating system to the cerebral coex from the limbic coex which is involved with the awareness of sensation. Though the patient may have intact corneal, cough, and swallow reflexes, they need not be protective. 