Apparatus Exposure Produces Profound Declines in Conditioned Nictitating-Membrane Responses to Discrete Conditioned Stimuli by the Rabbit (Oryctolagus cuniculus).

Abstract

The present experiments demonstrated that in the rabbit (Oryctolagus cuniculus) nictitacing-membrane (NM) preparation, exposure to the experimental apparatus produces profound declines in conditioned responding to a discrete conditioned stimulus (CS; Experiments 1, 2A, and 3). Moreover, this decremental effect is at most attenuated in only a minor way when the unconditioned stimulus (US) is presented during exposure to the apparatus (Experiment 2B). Controls for retention loss (Experiments 1 and 3) and for handling and placement in a different context (Experiment 3) did not produce significant declines in responding. These findings challenge theories of extinction that rely primarily on context-US associations but are more consistent with theories that assume context-CS-US associations.

Repeated acquisitions and extinctions in classical conditioning of the rabbit nictitating membrane response

“…Although they did not appear to play a role in the present results, the rabbit NM response is sensitive to both the global context provided by the apparatus cues (Hinson 1982;Kim 1986;Saladin and Tait 1986;Kehoe et al 2004;Poulos et al 2004) and conditional cues (occasion-setters) that have ranged up to a minute in length (Macrae and Kehoe 1995;Weidemann and Kehoe 1997;Rogers and Steinmetz 1998;Kehoe and Boesenberg 2002). Furthermore, the US-related internal context has the potential to make a contribution.…”

Extinction of a Classically Conditioned Response: Red Nucleus and Interpositus

“…Actually, extinction of the conditioned eyeblink response, unlike acquisition, is very dependent on context. Kehoe et al (2004) and Poulos et al (2006) established "extinction" of the CR simply by exposure to the conditioning context in the absence of CS presentations. Results of these behavioral studies on eyeblink conditioning as well as other learning paradigms (see above) support Bouton's (2004) comprehensive theory of extinction.…”

“…A number of behavioral theories have been proposed to account for this interference (Poulos et al, 2006), among the most prominent being the response-extinction hypothesis (Rescorla, 1997) and the context hypothesis (Bouton and Nelson, 1994;Kehoe et al, 2004). More recently, data using genetic and pharmacological techniques argue for the existence of a dissociation between response expression and extinction (Thomas et al, 1998;Ouyang and Thomas, 2005) in which memory retrieval and not conditioned responding is critical in extinction.…”

Conditioning-specific reflex modification of the rabbit (Oryctolagus cuniculus) nictitating membrane response is sensitive to context

“…There is considerable evidence for an effect of a shift in context between conditioning and extinction in a number of paradigms, including taste aversion learning (Westbrook et al, 1995), fear conditioning (Bouton, 2004), and classical conditioning of the rabbit NMR (Kehoe, Weidemann, & Dartnall, 2004). If the present contexts were discriminable, we might expect to see more CR extinction in rabbits that experienced the context shift between CS-US pairings and extinction than in rabbits that experienced the same context during both CS-US pairings and extinction.…”