A number of ways of taxonomizing human learning have been proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, between learning that takes place with versus without concurrent awareness, and between learning that involves the encoding of instances versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning derived from subliminal learning, (...) conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of these tasks is predominantly based on rule abstraction is questionable. When subjects cannot report the “implicitly learned” rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning. (shrink)

Evaluative conditioning (EC) is one of the terms that is used to refer to associatively induced changes in liking. Many controversies have arisen in the literature on EC. Do associatively induced changes in liking actually exist? Does EC depend on awareness of the fact that stimuli are associated? Is EC resistant to extinction? Does attention help or hinder EC? As an introduction to this special issue, we will discuss the extent to which the papers that are published in this issue (...) help to resolve some of the controversies that surround EC. We also speculate about possible boundary conditions of EC and attempt to reconcile conflicting results on the functional properties of EC. (shrink)

Two experiments were conducted to examine whether the resistance to extinction obtained in evaluative conditioning (EC) studies implies that EC is a qualitatively distinct form of classical conditioning (Baeyens, Eelen, & Crombez, 1995 Baeyens, F, Eelen, P, and Crombez, G, (1995a). Pavlovian associations are forever: On classical conditioning and extinction, Journal of Psychophysiology 9 ((1995a)), pp. 127–141.[Web of Science ®], [Google Scholar]a) or whether it is the result of an nonassociative artefact (Field & Davey, 1997 Field, AP, and Davey, GCL, (...) (1997). Conceptual conditioning: Evidence for an artifactual account of evaluative learning, Learning and Motivation 25 ((1997)), pp. 446–464.[Crossref], [Web of Science ®], [Google Scholar], 1998 Field, AP, and Davey, GCL, (1998). Evaluative conditioning: Arti‐fact or ‐fiction?‐ A reply to Baeyens, De Houwer, Vansteenwegen, and Eelen (1998), Learning and Motivation 29 ((1998)), pp. 475–491.[Crossref], [Web of Science ®], [Google Scholar], 1999 Field, AP, and Davey, GCL, (1999). Reevaluating evaluative conditioning: A nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm, Journal of Experimental Psychology: Animal Behavior Processes 25 ((1999)), pp. 211–224.[Crossref], [PubMed], [Web of Science ®], [Google Scholar]). Both experiments included between‐subjects control groups in addition to standard within‐subjects control conditions. In Experiment 1, only verbal ratings were measured in order to evaluate the effect of postacquisition CS‐only exposures on EC whereas in Experiment 2, verbal ratings and postextinction priming effects were measured. The results showed that the EC effects are demonstrable in a between‐subjects design and that the extinction procedure did not have any influence on the acquired evaluative value of CSs regardless of whether the verbal ratings or the priming effects were used as dependent variables. The present results provide evidence that EC is resistant to extinction and suggest an interpretation of EC as a qualitatively distinct form of associative learning. (shrink)

Two experiments are described that investigate the effects of attention in moderating evaluative conditioning (EC) effects in a picture‐picture paradigm in which previously discovered experimental artifacts (e.g., Field & Davey, 1999 Field, AP, and Davey, GCL, (1999). Reevaluating evaluative conditioning: A nonassociative explanation of conditioning effects in the visual evaluative conditioning paradigm, Journal of Experimental Psychology. Animal Behavior Processes 25 ((1999)), pp. 211–224.[Crossref], [PubMed], [Web of Science ®], [Google Scholar]) were overcome by counterbalancing conditioned stimuli (CSs) and unconditioned stimuli (USs) (...) across participants. Conditioned responses for individuals who had attention enhanced were compared against a control group and groups for whom attention was impeded using a distracter task. In a second experiment the effects of attention were dissociated from those of contingency awareness by using backward‐masked US presentations. The results of these experiments indicate that although associative EC effects may not be disrupted by a lack of contingency awareness, attention is an important factor in establishing conditioning. These results shed some light onto the possible boundary conditions that could explain past inconsistencies in obtaining EC effects in the visual paradigm. (shrink)

I present an overview of emotion theories, organised around the question of emotion causation. I argue that theories of emotion causation should ideally address the problems of elicitation, intensity, and differentiation. Each of these problems can be divided into a subquestion that asks about the relation between stimuli and emotions (i.e., the functional level of process description, cf. Marr, 1982) and a subquestion that asks about the mechanism and representations that intervene (i.e., the algorithmic level of process description). The overview (...) reveals that theories of emotion causation sometimes differ with regard to the kind of process that they hold responsible for emotion causation. More precisely, they hold different assumptions regarding the conditions under which the process is supposed to operate (optimal versus suboptimal), the format of the representations involved (propositional versus perceptual), and the object or input of the central process (stimulus versus responses/experience). Further, the overview reveals that theories of emotion causation sometimes differ with regard to the level of process description that they focus on. Finally, the overview brings to light several similarities among the theories discussed. (shrink)

Dual process accounts of affective learning state that the learning of likes and dislikes reflects a learning mechanism that is distinct from the one reflected in expectancy learning, the learning of signal relationships, and has different empirical characteristics. Affective learning, for example, is said not to be affected by: (a) extinction training; (b) occasion setting; (c) cue competition; and (d) awareness of the CS-US contingencies. These predictions were tested in a series of experiments that employed simple Pavlovian conditioning procedures. Neutral (...) visual pictures of geometric shapes, or tactile conditional stimuli (CS) were paired with aversive electrotactile unconditional stimuli (US). Dependent measures were physiological (skin conductance, blink startle modulation) or verbal (US expectancy, on-line and off-line ratings of CS pleasantness). Different combinations of these dependent measures were employed across different experiments in an attempt to assess affective and expectancy learning simultaneously. Changes in CS pleasantness as indexed by ratings or blink startle modulation were readily observed. However, contrary to the predictions from dual-process accounts, results indicated that acquired CS unpleasantness is subject to extinction, occasion setting, cue competition, and not found in absence of CS-US contingency awareness. (shrink)

Mitchell et al.'s claim, that their propositional theory is a single-process theory, is illusory because they relegate some learning to a secondary memory process. This renders the single-process theory untestable. The propositional account is not a process theory of learning, but rather, a heuristic that has led to interesting research.

Three experiments are reported that address the issue of awareness in evaluative learning in two different sensory modalities: visual and haptic. Attempts were made to manipulate the degree of awareness through a reduction technique (by use of a distractor task in Experiments 1 and 2 and by subliminally presenting affective stimuli in Experiment 3) and an induction technique (by unveiling the evaluative learning effect and requiring participants to try to discount the influence of the affective stimuli). The results indicate overall (...) that evaluative learning was successful in the awareness-reduction groups but not in the awareness-induction groups. Moreover, an effect in the opposite direction to that normally observed in evaluative learning emerged in participants aware of the stimulus contingencies. In addition, individual differences in psychological reactance were found to be implicated in the strength and direction of the effect. It is argued that these results pose serious problems for the contention that awareness is necessary for evaluative learning. (shrink)

In her commentary of Field (1999), Hammerl (1999) has drawn attention to several interesting points concerning the issue of contingency awareness in evaluative conditioning. First, she comments on several contentious issues arising from Field's review of the evaluative conditioning literature, second she critiques the data from his pilot study and finally she argues the case that EC is a distinct form of conditioning that can occur in the absence of contingency awareness. With reference to these criticisms, this reply attempts to (...) address Hammerl's comments by exploring the issues of how awareness is defined, how it is best measured, and whether it is reasonable to believe that EC uniformly occurs in the absence of contingency awareness. The article concludes that the available evidence supports Field's proposition that EC is, in fact, Pavlovian learning. (shrink)

Recent studies have shown that the basic evaluative conditioning (EC) effect (originally neutral stimuli acquiring an affective value congruent with the valence of the affective stimulus they were paired with) seems to be limited to participants who are unaware of the stimulus pairings. If participants are aware of the pairings, reactance effects occur (i.e., changes in the opposite direction of the valence of the affective stimulus). To examine whether these reactance effects are due to processes of conscious countercontrol or whether (...) the ratings reflect intrinsic feelings towards the stimuli, a new procedure was developed that included a bogus‐pipeline condition. In this procedure, which was adapted from attitude research, participants were connected to bogus lie detector equipment leading them to believe that their “true” affective‐evaluative responses were being observed. In Experiment 1, reactance effects occurred also in this procedure, suggesting that the effect is spontaneous and not due to processes of conscious countercontrol. In Experiment 2, these effects were replicated using a between‐subjects design in addition to the standard within‐subjects control condition. (shrink)

Evaluative learning refers to the change in the affective evaluation of a previously neutral stimulus that occurs after the stimulus has been associated with a second, positive or negative, affective stimulus . Four experiments are reported in which the AS was presented very briefly. Significant evaluative learning was observed in participants who did not notice the presentation of the affective stimuli or could not discriminate between the briefly presented positive and negative ASi when asked to do so . In two (...) other experiments , no significant learning effect was obtained. A meta-analysis performed on the present and previously reported results gave evidence for a small, though statistically reliable evaluative learning effect when ASi are presented “subliminally.” This finding supports the hypothesis that evaluative associations can be learned implicitly. (shrink)

The past 50 years have seen an accumulation of evidence suggesting that associative learning depends on high-level cognitive processes that give rise to propositional knowledge. Yet, many learning theorists maintain a belief in a learning mechanism in which links between mental representations are formed automatically. We characterize and highlight the differences between the propositional and link approaches, and review the relevant empirical evidence. We conclude that learning is the consequence of propositional reasoning processes that cooperate with the unconscious processes involved (...) in memory retrieval and perception. We argue that this new conceptual framework allows many of the important recent advances in associative learning research to be retained, but recast in a model that provides a firmer foundation for both immediate application and future research. (shrink)

There is good evidence that, in general, autonomic conditioning in humans occurs only when subjects can verbalize the contingencies of conditioning. However, one form of conditioning, evaluative conditioning (EC), seems exceptional in that a growing body of evidence suggests that it can occur without conscious contingency awareness. As such, EC offers a unique insight into what role contingency awareness might play in associative learning. Despite this evidence, there are reasons to doubt that evaluative conditioning can occur without conscious awareness. This (...) paper aims to critically review the EC literature and to draw some parallels to what is known about autonomic conditioning. In doing so, some important general issues about measuring contingency awareness are raised. These issues are illustrated with a brief report of an experiment in which a sensitive measure of contingency awareness is compared against a commonly used measure. (shrink)

A number of ways of taxonomizing human learning have been proposed. We examine the evidence for one such proposal, namely, that there exist independent explicit and implicit learning systems. This combines two further distinctions, (1) between learning that takes place with versus without concurrent awareness, and (2) between learning that involves the encoding of instances (or fragments) versus the induction of abstract rules or hypotheses. Implicit learning is assumed to involve unconscious rule learning. We examine the evidence for implicit learning (...) derived from subliminal learning, conditioning, artificial grammar learning, instrumental learning, and reaction times in sequence learning. We conclude that unconscious learning has not been satisfactorily established in any of these areas. The assumption that learning in some of these tasks (e.g., artificial grammar learning) is predominantly based on rule abstraction is questionable. When subjects cannot report the rules that govern stimulus selection, this is often because their knowledge consists of instances or fragments of the training stimuli rather than rules. In contrast to the distinction between conscious and unconscious learning, the distinction between instance and rule learning is a sound and meaningful way of taxonomizing human learning. We discuss various computational models of these two forms of learning. (shrink)

We argue that the effects of evaluative learning may occur (a) without conscious perception of the affective stimuli, (b) without awareness of the stimulus contingencies, and (c) without any awareness that learning has occurred at all. Whether the three experiments reported in our target article provide conclusive evidence for either or any of these assertions is discussed in the commentaries of De Houwer and Field. We respond with the argument that when considered alongside other studies carried out over the past (...) few decades, our experiments provide compelling evidence for a theory that posits a dissociation between evaluative learning and contingency awareness. (shrink)

During evaluative conditioning, a neutral conditional stimulus becomes pleasant or unpleasant after pairings with a positive/negative unconditional stimulus. Measures of US expectancy are...

Evaluative conditioning (EC) refers to the change in the valence of a conditioned stimulus (CS) due to its pairing with a positive or negative unconditioned stimulus (US). To the extent that core affect can be characterised by the two dimensions of valence and arousal, EC has important implications for the origin of affective responses. However, the distinction between valence and arousal is rarely considered in research on EC or conditioned responses more generally. Measuring the subjective feelings elicited by a CS, (...) the results from two experiments showed that (1) repeated pairings of a CS with a positive or negative US of either high or low arousal led to corresponding changes in both CS valence and CS arousal, (2) changes in CS arousal, but not changes in CS valence, were significantly related to recollective memory for CS–US pairings, (3) subsequent presentations of the CS without the US reduced the conditioned valence of the CS, with conditioned arousal being less susceptible to extinction and (4) EC effects were stronger for high arousal than low arousal USs. The results indicate that the conditioning of affective responses can occur simultaneously along two independent dimensions, supporting evidence in related areas that calls for a consideration of both valence and arousal. Implications for research on EC and the acquisition of emotional dispositions are discussed. (shrink)

Fulcher and Hammerl's (2001) important exploration of the role of contingency awareness in evaluative conditioning (EC) raises a lot of issues for discussion: (1) what boundaries, if any, exist between EC and affective learning paradigms?; (2) if EC does occur without awareness does this mean it is nonpropositional learning?; (3) is EC driven by stimulus-response (S-R), rather than stimulus-stimulus (S-S), associations and if so should it then surprise us that contingency awareness is not important?; and (4) if S-R associations are (...) at the heart of EC, should we automatically assume EC is part of a different learning mechanism to autonomic Pavlovian conditioning (Field, 2000a, 2000b)? This article, after a critical review of Fulcher and Hammerl's work, discusses these issues with reference to what can be realistically inferred about the mechanisms underlying EC. (shrink)

In this commentary, we assess the propositional approach to associative learning not only in terms of veridicality and falsifiability, but also in heuristic value. We remark that it has furthered our knowledge and understanding of human, as well as animal, associative learning. At the same time, we maintain that models developed from the association formation tradition continue to bear great heuristic value as well.

In three experiments, each of a set colour-unrelated distracting words was presented most often in a particular target print colour . In Experiment 1, half of the participants were told the word-colour contingencies in advance and half were not . The instructed group showed a larger learning effect. This instruction effect was fully explained by increases in subjective awareness with instruction. In Experiment 2, contingency instructions were again given, but no contingencies were actually present. Although many participants claimed to be (...) aware of these contingencies, they did not produce an instructed contingency effect. In Experiment 3, half of the participants were given contingency instructions that did not correspond to the correct contingencies. Participants with these false instructions learned the actual contingencies worse than controls. Collectively, our results suggest that conscious contingency knowledge might play a moderating role in the strength of implicit learning. (shrink)