Extinction of a taste aversion in the absence of the consummatory response.

Active avoidance of shock can be influenced by manipulations of the CS made while the subjects are curarized and unable to respond instrumentally. After training dogs to respond to a light to avoid shock, Solomon and Turner (1962) curarized them and presented one tone paired with shock (S + ) and another not paired (S ). The dogs subsequently emitted the instrumental avoidance response to S + and not to S -, although S + had been paired with shock only in the absence of any instrumental response. Similarly, extinction of a shockavoidance response can be accelerated if the CS is presented without shock to curarized subjects (Black, 1958; Solomon, Kamin, & Wynne, 1953). In Black's studies, dogs which had learned an avoidance response to a CS were given either the CS a large number of times while curarized or normal extinction trials. The dogs presented with the CS while curarized extinguished faster. Analogously, conditioned taste aversions can be conditioned and extinguished when the flavored stimulus is presented in a way that bypasses the subjects' normal consummatory-response system. Rats given an intravenous injection of saccharin solution and then made ill avoided saccharin when first allowed to drink it by mouth (Bradley & Mistretta, 1971). Domjan and Wilson (1972) either wiped the tonges of curarized rats with saccharin solution or washed saccharin solution through rats' mouths too quickly to permit ingestion, and then induced visceral upset. Subsequently, the rats