The role of awareness in Pavlovian conditioning: Empirical evidence and theoretical implications.

Abstract

This article reviews research over the past decade concerning the relationship between Pavlovian conditioning and conscious awareness. The review covers autonomic conditioning, conditioning with subliminal stimuli, eyeblink conditioning, conditioning in amnesia, evaluative conditioning, and conditioning under anesthesia. The bulk of the evidence is consistent with the position that awareness is necessary but not sufficient for conditioned performance, although studies suggestive of conditioning without awareness are identified as worthy of further investigation. Many studies have used inadequate measures of awareness, and strategies for increasing validity and sensitivity are discussed. It is concluded that conditioning may depend on the operation of a propositional system associated with consciousness rather than a separate, lower level system.

Standard delay eyeblink classical conditioning is independent of awareness.

“…Further, in response to a question raised by Lovibond and Shanks (2002), we note that the 2 patients who scored the poorest on the questionnaire (M ϭ 8.5 correct) conditioned even better than the 2 patients who scored the best (M ϭ 14.0 correct; 24.2% differential CRs across the final 60 trials vs. 13.7% differential CRs, respectively).…”

“…Our recent study of differential eyeblink conditioning in amnesic patients and healthy volunteers (Clark & Squire, 1998) was discussed at length by Lovibond and Shanks (2002). They raised several concerns about the study, including that the cutoff score (Ն13 correct out of 17) used to designate participants as aware may have been too high and that asking questions at the end of the session (and after other unrelated questions had been asked) was not optimal.…”

“…Third, although many of the points raised by Lovibond and Shanks (2002) concerning the study of differential conditioning are useful considerations, the points they raised do not explain why trace eyeblink conditioning but not delay eyeblink conditioning reveals a role for awareness. The authors offered the speculation that perhaps learning the differential rule is easier in delay conditioning, whereas learning the temporal order of the CSϩ and US is easier in trace conditioning.…”

Reinstatement of Conditioned Fear in Humans Is Context Dependent and Impaired in Amnesia.

“…Proponents of the multiple memory system viewpoint hypothesize a more restricted effect of contextual manipulations on implicit forms of memory, given that contextual binding is a distinguishing characteristic of episodic memory formation (Tulving, 1983). These theories typically classify simple forms of Pavlovian conditioning as examples of implicit memory, especially for single-cue delay procedures in which learning can occur in the absence of explicit knowledge (Clark, Manns, & Squire, 2002;LaBar & Disterhoft, 1998; but see Lovibond & Shanks, 2002). The results of Experiments 1 and 3, then, implicate the contextual modulation of an implicitly derived behavioral response.…”

Contingency awareness and fear inhibition in a human fear-potentiated startle paradigm.

“…The term contingency awareness is defined as the subject's knowledge of the reinforcement contingencies in the experiment (Lovibond & Shanks, 2002). Lovibond (2004) proposed a cognitive model of fear conditioning in which cognitive awareness of experimental contingencies is necessary for fear conditioning and extinction.…”