Absence of a generalization decrement in the poison-induced avoidance of interoceptive stimuli in the rat

Abstract

Rats poisoned either immediately or 4 h after consuming one novel solution were subsequently tested with either a water vs, the conditioned novel solution choice or with a water vs. a second unconditioned novel solution choice. The results showed that: (1) there was a significant avoidance of both solutions by the immediately poisoned groups compared to their respective controls. and (2) there was a clear avoidance of the unconditioned novel solution and a marginal avoidance of the conditioned novel solution by the 4-h poisoned groups compared to their respective controls. The absence of a generalization decrement indicates that associative mechanisms such as stimulus generalization cannot adequately account for these results. An alternative explanation. based on the interaction of associative mechanisms with the habituation and sensitization of neophobia is proposed.

Cross-modality contrast: Exteroceptive context habituation enhances taste neophobia and conditioned taste aversions

“…In addition to providing support for the view that there is an interplay between habituation and conditioning in the taste aversion paradigm (Mitchell, Parker, & Johnson, 1976;Mitchell, Scott, & Mitchell, 1977), these experiments confirm recent reports that the exteroceptive environment plays an important modulating role in taste-aversion learning. Rudy, Rosenberg, and Sandell (1977) demonstrated that the taste-familiarity effect can be significantly disrupted by exposing rats to novel exteroceptive stimulation prior to conditioning with a familiar taste.…”

Positive correlation between pre- and postconditioning saccharin intake in taste-aversion learning

“…The present results, showing an approximate reduction of saccharin intake of about 50070 in the contingently poisoned groups on the second presentation, irrespective of the amount of saccharin drunk on the initial exposure, strongly supports the suggestion that the associative es-ues component is superimposed on a neophobic reaction to the novel taste + exteroceptive context in taste-aversion conditioning (Mitchell, Hoch, & Fitzsimmons, 1975;Mitchell, Parker, & Johnson, 1976).…”

Environment-dependent taste-aversion extinction: A question of stimulus novelty at conditioning

“…This correlation of the magnitude of the conditioning trial neophobia with the magnitude of the contextdependent conditioning effect, also attested to in our previous studies, supports the two-process theory advanced by Mitchell and his co-workers (e.g., Mitchell, Parker, & Johnson, 1976). According to this theory, an associative CS-UCS component is superimposed upon a neophobic response to the taste + exteroceptive context in taste-aversion learning.…”