Figure 2.

Noxious pressure-induced activation of secondary somatosensory cortex (SII) and insula (Ins) in cynomolgus macaques under various types of anesthetic or sedative agents. Macaques were treated with either A) propofol, B) pentobarbital, C) isoflurane or D) MMB. The average of 3 coronal brain activation maps under propofol sedation (30 mg/kg/hr.) is shown. Coronal section brain activation maps averaged from 5 macaques treated with either pentobarbital, isoflurane or medetomidine/midazolam/butorphanol (MMB) are shown. Activation of the somatosensory cortex SII and Ins was observed with noxious pressure applied to the right foot under either propofol or pentobarbital sedation. However, no activation was observed with either isoflurane or MMB treatment. L, anatomic left; R, anatomic right.