to distinguish between functional or organic anesthesia; the patient, eyes closed, is told to say “yes” or “no” on feeling (or not) the touch of the examiner's finger. In functional anesthesia, the patient may say “no” when an anesthetic area is touched. In organic anesthesia, the patient will say nothing, being unaware that he is touched.
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Examples: glitazone, GI cocktail, etc.