Omer Van den Bergh

Contingency awareness in evaluative conditioning: A case for unaware affective-evaluative learning

Abstract According to Martin and Levey (1987) evaluative conditioning is different from signal learning, i.e. the acquisition of knowledge about predictive relations between environmental events. The hypothesis was tested that evaluative conditioning, unlike signal learning, does not require awareness of the CS-US contingency. In three pilot experiments it was demonstrated that pairing neutral stimuli with either liked or disliked stimuli is sufficient to change neutral stimuli into a positive or negative direction. As indicated by postconditioning recognition questionnaires, this evaluative shift did not require and was not even influenced by contingency awareness. These findings were replicated and corroborated in an experiment, using a concurrent awareness assessment procedure and more fine-grained evaluative response measurements. The relevance of this conditioning without contingency awareness is discussed in the context of recent information processing models of Pavlovian conditioning.

Once in contact always in contact: Evaluative conditioning is resistant to extinction

Abstract The present study aimed at obtaining some further support for the hypothesis of a distinction between two basically different kinds of learning in a Pavlovian conditioning preparation: signal-learning and affective-evaluative learning ( Baeyens et al. , 1988a,b ; Levey and Martin, 1987 ). In this respect, we conducted an experiment to verify the Levey and Martin (1983, 1987) hypothesis that, unlike signal-learning, evaluative conditioning should be resistant to extinction. Mere contingent presentation of neutral with (dis)liked stimuli was sufficient to change the affective—evaluative tone of the originally neutral stimuli in a (negative) positive direction ( p not have any influence on the acquired evaluative value of the originally neutral stimuli ( p p et al. , 1986).

Human evaluative conditioning: Acquisition trials, presentation schedule, evaluative style and contingency awareness

Two different processes may be operative in human Pavlovian conditioning: signal learning and evaluative learning. Whereas most studies on evaluative conditioning focused on a mere demonstration of the phenomenon or on a theoretical analysis of the underlying processes, some basic parameters of evaluative learning are still unexplored. Hence, using the standard neutral picture--(dis)liked picture pairing paradigm (Baeyens, Eelen & Van den Bergh, 1990), in this study the effect of two parameters of evaluative conditioning was assessed on a between-subjects base, namely the Number of Acquisition Trials (2/5/10/20) and the Presentation Schedule of the stimulus pairs (blockwise or random). Additionally, the study included an exploratory analysis of the potential effects of the Evaluative Style of subjects (Feelers vs Thinkers, operationalized in terms of speed of emitting evaluations). Finally, the relationship between contingency awareness and evaluative learning was reassessed. Neutral-liked conditioning was found to be quadratically related to the number of acquisition trials (increase in effect up to 10 trials, decrease from 10 to 20 trials), whereas neutral-disliked conditioning linearly increased with increasing numbers of trials. Randomized vs blockwise presentation schedules of the stimulus pairs did differentially affect the overall pattern of conditioning, but in a way which was both unexpected and difficult to account for theoretically. Both the Evaluative Style of subjects and contingency awareness were demonstrated to be generally orthogonal to conditioned shifts in CS valence. Based on these findings, some practical suggestions are provided for the application of evaluating conditioning based therapeutical interventions to affective-behavioral disorders which are centred around inappropriate (dis)likes.

The content of learning in human evaluative conditioning: Acquired valence is sensitive to US-revaluation

Abstract Evaluative conditioning refers to the observation that the mere contingent presentation of neutral with (dis)liked stimuli changes the valence of the originally neutral stimuli in a (negative) positive direction. Two theoretical accounts of the representational structure built up during evaluative conditioning are contrasted: intrinsic change versus referential learning. It is argued that previous findings on evaluative conditioning (for example, resistance to extinction) seem to favor intrinsic change explanations, but do not actually allow any definite conclusions. The postconditioning US-revaluation paradigm was used to obtain a more straight-forward result. In Experiment 1, a technique was developed to alter the valence of originally strongly (dis)liked USs (pictures of faces). In Experiment 2, we first presented a contingency between neutral (CS) and (dis)liked pictures of faces (US), and next applied the US revaluation technique. Contrary to expectations based on intrinsic change accounts, we observed that the postconditioning US revaluation did affect the acquired value of the CS; this result was confirmed in a 1-month follow up. Hence, we conclude that the acquired evaluative meaning of the CS is referential, ultimately relying on an association between CS and US representations.

Inaccurate perception of asthma symptoms: a cognitive-affective framework and implications for asthma treatment.

Inaccurate perception of respiratory symptoms is often found in asthma patients. Typically, patients who inaccurately perceive asthma symptoms are divided into underperceivers and overperceivers. In this paper we point out that this division is problematic. We argue that little evidence exists for a trait-like stability of under- and overperception and that accuracy of respiratory symptom perception is highly variable within persons and strongly influenced by contextual information. Particularly, expectancy and affective cues appear to have a powerful influence on symptom accuracy. Based on these findings and incorporating recent work on associative learning, attention and mental representations in anxiety and symptom perception, we propose a cognitive-affective model of symptom perception in asthma. The model can act as a framework to understand both normal perception as well as under- and overperception of asthma symptoms and can guide the development of affect-related interventions to improve perceptual accuracy, asthma control and quality of life in asthma patients.

Acquired affective-evaluative value: Conservative but not unchangeable

In a previous study on Evaluative Conditioning it was found that unlike signal-learning, evaluative learning is resistant to extinction. In the present experiment we tried to replicate and corroborate this finding. In addition, we investigated the effectiveness of a counterconditioning procedure to alter acquired evaluative value. On a within-subject base (n = 30), it was found that the mere contingent presentation of neutral with (dis)liked pictures of human faces was sufficient to change the affective-evaluative tone of the originally neutral stimuli in (negative) positive direction. Next, we replicated the finding that an extinction procedure does not have any influence on the acquired evaluative value of the originally neutral stimuli, and this even in subjects fully aware of the extinction presentations. We demonstrated the effectiveness of a counterconditioning procedure to alter acquired evaluative value, and in addition, found some evidence that awareness of the counterconditioning manipulations is not a prerequisite for its effectiveness. The theoretical consequences of these findings are phrased in terms of a fundamental distinction between signal-learning and evaluative learning, and some important implications for the behavioral treatment of affective-emotional disorders are suggested.

Media warnings about environmental pollution facilitate the acquisition of symptoms in response to chemical substances.

Objective Previous studies showed that somatic symptoms can be acquired in response to chemical substances using an associative learning paradigm, but only when the substance was foul smelling and not when it smelled pleasant. In this study, we investigated whether warnings about environmental pollution would facilitate acquiring symptoms, regardless of the pleasantness of the smell. Method One group received prior information framing the study in the context of the rapidly increasing chemical pollution of our environment. Another group received no prior information. Conditional odor stimuli (CS) were diluted ammonia (foul-smelling) and niaouli (neutral-positive smelling); the unconditional stimulus (UCS) was 10% CO2-enriched air. Each subject breathed one odor mixed with CO2 and a control odor mixed with air in 80-sec breathing trials. The type of odor mixed with CO2 was counterbalanced across participants. Next, the same breathing trials were administered without CO2. Breathing behavior was measured during each trial; subjective symptoms were assessed after each trial. Results Only participants who had been given warnings about environmental pollution reported more symptoms to the odor that had previously been associated with CO2, compared with the control odor. This was so for both the foul- and the pleasant-smelling odor. Symptom learning did not occur in the group that did not receive warnings. The elevated symptom level could not be accounted for by altered respiratory behavior, nor by experimental demand effects. Conclusions Raising environmental awareness through warnings about chemical pollution facilitates learning of subjective health symptoms in response to chemical substances.

Generalization of acquired somatic symptoms in response to odors: a pavlovian perspective on multiple chemical sensitivity.

Objective Somatic symptoms that occur in response to odors can be acquired in a pavlovian conditioning paradigm. The present study investigated 1) whether learned symptoms can generalize to new odors, 2) whether the generalization gradient is linked to the affective or irritant quality of the new odors, and 3) whether the delay between acquisition and testing modulates generalization. Methods Conditional odor stimuli (CS) were (diluted) ammonia and niaouli. One odor was mixed with 7.4% CO2-enriched air (unconditional stimulus) during 2-minute breathing trials (CS+ trial), and the other odor was presented with air (CS− trial). Three CS+ and three CS− trials were conducted in a semirandomized order (acquisition phase). The test phase involved one CS+-only (CS+ without CO2) and one CS− test trial, followed by three trials using new odors (butyric acid, acetic acid, and citric aroma). Half of the subjects (N = 28) were tested immediately, and the other half were tested after 1 week. Ventilatory responses were measured during and somatic symptoms were measured after each trial. Results Participants had more symptoms in response to CS+-only exposures, but only when ammonia was used as the CS+. Also, generalization occurred: More symptoms were reported in response to butyric and acetic acid than to citric aroma and only in participants who had been conditioned. Both the selective conditioning and the generalization effect were mediated by negative affectivity of the participants. The delay between the acquisition and test phases had no effect. Conclusions Symptoms that occur in response to odorous substances can be learned and generalize to new substances, especially in persons with high negative affectivity. The findings further support the plausibility of a pavlovian perspective of multiple chemical sensitivity.

Extinction, generalization, and return of fear: A critical review of renewal research in humans

The main behavioral signature of fear extinction is its fragility. This is exemplified by the renewal effect, where a change in the background context produces recovery of fear to a conditioned-and-extinguished stimulus. Renewal is the backbone of a widely accepted theory of extinction in animal research, as well as an important experimental model to screen novel treatment techniques. This has led to an explosion of fear renewal research in humans. However, the mere observation of return of fear in a renewal procedure is not sufficient to validate this particular theory of extinction in the tested sample/procedure. Here, we systematically outline a set of experimental tests that aid in evaluating alternative extinction/renewal mechanisms. We examine published renewal studies in human fear conditioning and conclude that the prevailing theory of extinction is often taken for granted, but critical tests are lacking. Including these tests in future research will not only reveal the fear extinction mechanism in humans, but also inspire further developments in extinction treatment research.

Hyperventilation beyond fight/flight: respiratory responses during emotional imagery

Hyperventilation (HV) is often considered part of a defense response, implying an unpleasant emotion (negative valence) combined with a strong action tendency (high arousal). In this study, we investigated the importance of arousal and valence as triggers for HV responses. Forty women imagined eight different scripts varying along the arousal and valence dimensions. The scripts depicted relaxation, fear, depressive, action, and desire situations. After each trial, the imagery was rated for valence, arousal, and vividness. FetCO2, inspiratory and expiratory time, tidal volume, and pulse rate were measured in a nonintrusive way. FetCO2 drops and decreases in inspiratory and expiratory time occurred in all but the depressive and the relaxation scripts, suggesting that a defense conceptualization of hyperventilation is not always appropriate.