Negative Unconditioned Stimuli Research Articles

Exploring the association between neuroticism and negativity bias in evaluative counterconditioning

People high on neuroticism express a negativity bias in attention, memory, and interpretation, giving primacy to negative rather than positive information. Investigating additional forms of negativity bias in neuroticism could provide further insights into the situations where people who score high on neuroticism tend to remain anchored on negative aspects. We examined whether neuroticism is related to negativity bias in evaluative learning. Instruction-based and experience-based counterconditioning are two evaluative learning procedures in which a conditioned stimulus (CS) is related to a positive or a negative unconditioned stimulus (US) in Phase 1 and with a US of the opposite valence in Phase 2. Using these procedures, we obtained partial support for a negativity bias in counterconditioning among people who scored high on neuroticism. Specifically, participants scoring high on negative emotionality altered the CSs ratings more easily from positive to negative than from negative to positive, a pattern observed in instruction-based counterconditioning (Experiment 1) but not in experience-based counterconditioning (Experiment 2). In line with previous findings, we could conclude that people who score high on neuroticism tend to give primacy to emotionally negative information at the expense of positive information, particularly in ambiguous (learning) contexts.

Choosing What You Like or Liking What You Chose? Sampling’s Impact on Evaluation and the Role of Idiosyncratic Reactions to Valent Stimuli

Recent work incorporating autonomy into an evaluative conditioning procedure provided evidence of a sampling decision effect in which high-autonomy participants positively shifted their evaluations of frequently sampled conditioned stimuli (CSs), regardless of whether they were consistently paired with positive or negative unconditioned stimuli (USs). The current work modified this paradigm by also measuring participants’ evaluations of the sampled USs. Two experiments replicate the sampling decision effect for neutral CSs in a new variant of the paradigm while ruling out the alternative possibility that the effect is driven by idiosyncratic variance in participants’ reactions to the USs. In addition, Experiment 2 suggests that the sampling decision effect does not extend to the paired, valent stimuli. Together, these results further suggest that it is the act of sampling a stimulus more frequently that predicts a positive evaluative shift toward it.

Nucleus accumbens neurons dynamically respond to appetitive and aversive associative learning.

To survive, individuals must learn to associate cues in the environment with emotionally relevant outcomes. This association is partially mediated by the nucleus accumbens (NAc), a key brain region of the reward circuit that is mainly composed by GABAergic medium spiny neurons (MSNs), that express either dopamine receptor D1 or D2. Recent studies showed that both populations can drive reward and aversion, however, the activity of these neurons during appetitive and aversive Pavlovian conditioning remains to be determined. Here, we investigated the relevance of D1- and D2-neurons in associative learning, by measuring calcium transients with fiber photometry during appetitive and aversive Pavlovian tasks in mice. Sucrose was used as a positive valence unconditioned stimulus (US) and foot shock was used as a negative valence US. We show that during appetitive Pavlovian conditioning, D1- and D2-neurons exhibit a general increase in activity in response to the conditioned stimuli (CS). Interestingly, D1- and D2-neurons present distinct changes in activity after sucrose consumption that dynamically evolve throughout learning. During the aversive Pavlovian conditioning, D1- and D2-neurons present an increase in the activity in response to the CS and to the US (shock). Our data support a model in which D1- and D2-neurons are concurrently activated during appetitive and aversive conditioning.

The Moderating Role of Neuroticism on Evaluative Conditioning: Evidence From Ambiguous Learning Situations

Numerous studies have demonstrated a link between neuroticism and negative biases. Although some studies suggest that people with high neuroticism give more weight to negative information, others suggest that they respond more strongly to both positive and negative information. We investigated whether neuroticism is related to the evaluation of conditioned stimuli (CSs) in evaluative conditioning procedures that involve ambiguous learning conditions. We created ambiguous situations where CSs were paired with unconditioned stimuli (USs) consisting of both positive and negative pictures (Experiment 1) or paired alternatingly with positive and negative USs (Experiment 2). In addition to CSs consistently paired with positive and negative USs, we introduced neutral USs as a control condition. Our findings revealed that neurotic individuals negatively evaluated the CSs from ambiguous conditions relative to neutral conditions. In addition, participants with high neuroticism scores generally rated CSs more negatively. Theoretical and clinical implications of these results are discussed.

Effect of emotion dysregulation and emotion regulation strategies on evaluative conditioning

Evaluative conditioning (EC) appears when a neutral conditioned stimulus (CS) is repeatedly paired with a positive or negative unconditioned stimulus (US). Most studies on EC have focused on the influence of procedural factors (e.g., number of presentations) and awareness, while emotional factors have been understudied. However, literature shows that emotional processes could be involved. In this paper, we assume that, upon appraisal, the US elicits a particular emotion that is then paired with the CS. In this perspective, the ability to regulate emotions could modulate how individuals pay attention to stimuli, appraise them, and, more generally, use them. For these reasons, emotion regulation could be an interindividual moderator of the EC. To test this assumption, we explore whether (i) emotional dysregulation and (ii) emotional regulation strategies moderate EC effects. We conducted an integrative analysis (n = 236) based on two studies using the Difficulties in Emotion Regulation Scale and an observational study using the Emotion Regulation Questionnaire (n = 128). Higher levels of emotional dysregulation were associated with less positive conditioning. Furthermore, the reappraisal strategy was associated with higher positive conditioning. Therefore, people differ in how they are conditioned (particularly positively conditioned), and part of it is because of emotion regulation differences. This contribution opens several new questions for the EC field to understand more precisely when and where these emotional processes are involved.

Evaluative context and conditioning effects among same and different objects.

We address an apparent discrepancy in the literature on how context stimuli influence evaluations of target stimuli. While a rich literature suggests that target evaluations are often contrasted away from the valence of context stimuli, reported effects of evaluative conditioning (EC) are almost exclusively assimilative. Specifically, when a neutral conditioned stimulus (CS) repeatedly co-occurs with a positive unconditioned stimulus (US), the CS is later evaluated more positively. Contrast effects from mere co-occurrences are absent in the EC literature. We hypothesized that this can be explained by the stimulus composition in EC tasks, which usually depict different objects as target (CS) and context (US). In 10 experiments, we confirmed that when target and context stimuli depict different objects, assimilation clearly dominates. Yet, when target and context depict stimuli from the same object class, contrast effects become dominant. These contrast effects are invisible in standard EC tasks because CSs are contrasted with all positive and negative USs of a given stimulus set. The present work thereby identifies a central determinant of the direction that evaluative context and conditioning effects take. While different-object contexts evoke assimilation, same-object contexts increase the likelihood of contrastive evaluations. We discuss the various theoretical and practical implications of our findings. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

“Paint It Black”

Abstract. The present study is a first attempt to link self-reported difficulties in everyday emotion regulation (ER) with evaluative conditioning (EC). We conducted a within-subject study in which participants (n = 90) filled the Difficulties in Emotion Regulation Scale (DERS) and were exposed to neutral conditioned stimulus (CS) paired with mildly or highly arousing negative unconditioned stimuli (USs) and positive USs. Participants then filled a contingency awareness measure. Results showed (i) that CSs paired with highly arousing negative USs were more negatively evaluated, (ii) that the EC effect with highly and mildly arousing negative USs was stronger among participants with greater self-reported difficulties in everyday ER. Moreover, participants were more likely to be aware of the CS-US contingencies with highly (vs. mildly) arousing negative USs. Implications for the understanding of maladaptive behaviors and for future directions in EC research are discussed.

Evaluative Conditioning From the Perspective of the Associative-Propositional Evaluation Model

Evaluative conditioning (EC) is defined as the change in the evaluation of a conditioned stimulus (CS) due to its pairing with a positive or negative unconditioned stimulus (US). According to the associative-propositional evaluation (APE) model, EC effects can be the result of two functionally distinct learning mechanisms: associative and propositional learning. The current article reviews the core assumptions of the APE model regarding (1) the defining features of associative and propositional learning, (2) the mental representations resulting from the two learning mechanisms, (3) the processes involved in the behavioral expression of these representations, and (4) the automatic versus controlled nature of the processes underlying EC effects. In addition to reviewing the core assumptions of the APE model, the article reviews relevant evidence to illustrate the theory’s main hypotheses, its explanatory and predictive power, as well as empirical challenges for the theory.

A Declarative Memory Model of Evaluative Conditioning

I propose a Declarative Memory Model (DMM) of evaluative conditioning (EC). EC effects are changes in the valence of a conditioned stimulus (CS) due to previous pairings with a positive or negative unconditioned stimulus (US; e.g., De Houwer, 2007, https://doi.org/10.1017/S1138741600006491). According to the DMM, EC effects are found if (1) a memory trace is formed in the learning phase that links the CS to evaluative information from the US, if (2) this trace survives the retention interval, if (3) the trace or part of it is consciously retrieved when the CS is being evaluated, and if (4) the retrieved trace is used in the CS evaluation. For each of these stages, I make separate predictions about EC effects, many of which are based on empirical research on declarative memory. Where available, I report and discuss empirical evidence on EC that speaks to these hypotheses. The available empirical evidence is largely in line with the predictions of the DMM. Several predictions, however, have yet to be tested and some findings are ambiguous. While the DMM specifies conditions under which CS-US pairings should lead to a valence change, it does not deny the possibility that other processes might lead to a change in attitude as well. Advantages of the DMM are its foundation on declarative memory research, its applicability for attitude change effects in general, and its suitability for predictions of EC effects in the real world.

Anatomy and behavioral function of serotonin receptors in Drosophila melanogaster larvae.

The biogenic amine serotonin (5-HT) is an important neuroactive molecule in the central nervous system of the majority of animal phyla. 5-HT binds to specific G protein-coupled and ligand-gated ion receptors to regulate particular aspects of animal behavior. In Drosophila, as in many other insects this includes the regulation of locomotion and feeding. Due to its genetic amenability and neuronal simplicity the Drosophila larva has turned into a useful model for studying the anatomical and molecular basis of chemosensory behaviors. This is particularly true for the olfactory system, which is mostly described down to the synaptic level over the first three orders of neuronal information processing. Here we focus on the 5-HT receptor system of the Drosophila larva. In a bipartite approach consisting of anatomical and behavioral experiments we describe the distribution and the implications of individual 5-HT receptors on naïve and acquired chemosensory behaviors. Our data suggest that 5-HT1A, 5-HT1B, and 5-HT7 are dispensable for larval naïve olfactory and gustatory choice behaviors as well as for appetitive and aversive associative olfactory learning and memory. In contrast, we show that 5-HT/5-HT2A signaling throughout development, but not as an acute neuronal function, affects associative olfactory learning and memory using high salt concentration as a negative unconditioned stimulus. These findings describe for the first time an involvement of 5-HT signaling in learning and memory in Drosophila larvae. In the longer run these results may uncover developmental, 5-HT dependent principles related to reinforcement processing possibly shared with adult Drosophila and other insects.

Processing fluency: An inevitable side effect of evaluative conditioning

Human preferences can be shaped by evaluative conditioning (EC), which describes observed changes in liking of an initially neutral stimulus (conditioned stimulus) due to repeated paired presentations with an inherently positive or negative stimulus (unconditioned stimulus). The experimental procedure of EC implies that participants are repeatedly exposed to the conditioned stimulus. Prior research suggests that repeated exposure to stimuli facilitates their processing. Furthermore, the resulting experience of processing fluency is known to shape human preferences through its inherent positive valence. Surprisingly, however, the role of processing fluency due to repeated stimulus exposure has never been directly investigated within the context of EC. The present research extends current conceptualizations of EC by incorporating processing fluency. In particular, it presents the first study that differentiates between a direct effect of stimulus pairing and a fluency-mediated effect of stimulus repetition on liking in a standard EC procedure. This approach helps to answer the open theoretical questions of why negative EC (i.e., EC applying negative unconditioned stimuli) tends to produce smaller effects than positive EC (i.e., EC applying positive unconditioned stimuli), and why positive EC is less susceptible to extinction than negative EC. On this basis, we strongly recommend considering processing fluency in theoretical models and empirical studies on EC and other forms of evaluative learning.

Generalization of evaluative conditioning toward foods: Increasing sensitivity to health in eating intentions.

Evaluative conditioning (EC), the pairing of objects (conditioned stimuli; CS) with positive and negative unconditioned stimuli (US) in order to induce attitude change, has proven to be a viable method of changing attitudes toward foods and corresponding eating behaviors. Positively conditioning healthy foods and negatively conditioning unhealthy foods should result in healthier food choices. Of interest in the current research is the extent to which EC can generalize beyond the conditioned foods to entire dimensions underlying food judgment, such as health and taste. The current research included 2 EC experiments configured in accord with the Implicit Misattribution Model (IMM; Jones, Fazio, & Olson, 2009). Four healthy CS foods were paired with positive US and 4 unhealthy CS foods were paired with negative US. Participants then reported eating intentions for a variety of foods, including non-CS foods. Experiment 1 demonstrated that conditioning a few exemplar food items increased sensitivity to health and decreased sensitivity to taste when judging a variety of additional foods. Experiment 2 replicated the generalization effect with regard to health sensitivity, but only when a task that preceded the EC procedure promoted, rather than interfered with, categorization of the CS foods by health. This research shows that EC can generalize to an entire dimension underlying food judgment and that this effect is facilitated by accessibility of the health dimension at the time of exposure to the EC pairings. (PsycINFO Database Record

Affective learning in adults with intellectual disability: an experiment using evaluative conditioning.

Evaluative conditioning is a form of affective learning in which initially neutral stimuli acquire an affective value through association with negative or positive stimuli. Recent research shows an important role for cognitive resources in this type of learning. This form of affective learning has rarely been studied in intellectual disability (ID). We examined evaluative conditioning in 16 adults with mild to moderate ID compared to age- and gender-matched control participants. Neutral shapes and symbols were repeatedly paired with positive, neutral or negative unconditioned stimuli (faces or International Affective Picture System images). There was also an extinction phase. There was significant acquisition of conditioning in both groups. Stimuli paired with positive images were evaluated more positively, and stimuli paired with negative images were evaluated more negatively. Post-extinction ratings however show that these novel affective associations were not maintained by individuals with ID as much as by individuals in the control group. We conclude that ID modulates some aspects of affective learning but not necessarily initial preference acquisition.

Is evaluative conditioning really resistant to extinction? Evidence for changes in evaluative judgements without changes in evaluative representations

Evaluative conditioning (EC) is defined as the change in the evaluation of a conditioned stimulus (CS) due to its pairing with a positive or negative unconditioned stimulus (US). Although several individual studies suggest that EC is unaffected by unreinforced presentations of the CS without the US, a recent meta-analysis indicates that EC effects are less pronounced for post-extinction measurements than post-acquisition measurements. The disparity in research findings suggests that extinction of EC may depend on yet unidentified conditions. In an attempt to uncover these conditions, three experiments (N = 784) investigated the influence of unreinforced post-acquisition CS presentations on EC effects resulting from simultaneous versus sequential pairings and pairings with single versus multiple USs. For all four types of CS–US pairings, EC effects on self-reported evaluations were reduced by unreinforced CS presentations, but only when the CSs had been rated after the initial presentation of CS–US pairings. EC effects on an evaluative priming measure remained unaffected by unreinforced CS presentations regardless of whether the CSs had been rated after acquisition. The results suggest that reduced EC effects resulting from unreinforced CS presentations are due to judgement-related processes during the verbal expression of CS evaluations rather than genuine changes in the underlying evaluative representations.

Evaluative conditioning of food technologies in China: Moderating effect of social trust

This study provides an initial examination of the evaluative conditioning (EC) of consumers’ attitudes toward food technologies in China, including how EC can affect consumer acceptance of new technology when participants possess different levels of social trust. In a study using the EC paradigm and a combination of between-subjects control groups and within-subjects control conditions, participants considered three food technologies (conventional, enzyme, and genetic), paired with affectively positive, neutral, and negative images. Subsequent evaluative measurements revealed that EC can explain attitude formation toward food technologies in China when consumers see affective images, but the strength of the effects varies at different levels of social trust. Participants with a high level of trust in the institutions that promote and regulate the technologies can be conditioned both positively and negatively, independent of food technology. Participants with a low level of trust can be conditioned too, but only when the technology is paired with negative unconditioned stimuli. If social trust is low, positive conditioning of food technologies is not demonstrated in this study.

What is learned from repeated pairings? On the scope and generalizability of evaluative conditioning.

The investigation of evaluative conditioning (EC) has been mainly concerned with the conditioning of individual stimuli. Namely, a specific conditioned stimulus (CS) is paired with a positive or negative unconditioned stimulus and consequently acquires the valence of the unconditioned stimulus. In the present article, we expand the notion of EC to CS cues (e.g., gender) as distinguished from CS objects (e.g., an individual). We developed a conditioning paradigm that allows for the simultaneous investigation of both types of EC effects, evaluative identity conditioning and evaluative cue conditioning. The experiments demonstrate that EC has the potential to change attitudes not only toward CS individuals but also toward CS cues. We applied this twofold approach to both impoverished and more complex learning environments, demonstrating that evaluative identity conditioning is dependent on stimulus complexity while evaluative cue conditioning depends on the complexity of the stimulus context. The findings have distinct implications for the generalization of EC effects as well as for the investigation of EC.

Simultaneous conditioning of valence and arousal

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.

Evaluative conditioning depends on higher order encoding processes

Evaluative conditioning (EC) is commonly conceived as stimulus-driven associative learning. Here, we show that internally generated encoding activities mediate EC effects: Neutral conditioned stimuli (CS) faces were paired with positive and negative unconditioned stimuli (US) faces. Depending on the encoding task (Is CS a friend vs. enemy of US?), Experiment 1 yielded either normal EC effects (CS adopting US valence) or a reversal. This pattern was conditional on the degree to which encoding judgements affirmed friend or enemy encoding schemes. Experiments 2a and 2b replicated these findings with more clearly valenced US faces and controlling for demand effects. Experiment 3 demonstrated unconditional encoding effects when participants generated friend or enemy relations between CS and US faces. Explicitly stated friend or enemy relations in Experiment 4 left EC effects unaffected. Together, these findings testify to the importance of higher order cognitive processes in conditioning, much in line with recent evidence on the crucial role of conditioning awareness.

Individual differences in evaluative conditioning and reinforcement sensitivity affect bet-sizes during gambling

This study investigated the relationship between evaluative conditioning (EC), reinforcement sensitivity, and risk-taking on a simulated slot machine in a lab setting. Participants (51 female, 49 male, mean age 21.01 years [SD = 2.49] healthy adults) completed an EC paradigm with both negative unconditioned stimuli (negative EC) and positive unconditioned stimuli (positive EC). A negative EC by positive EC interaction effect indicated that those who did not show negative EC or positive EC gambled with lower average bet-size compared to the other participants. Scores on the fight-flight-freeze system (FFFS) and scores on the behavioral approach subscale Reward responsiveness (BAS-RR) were positively associated with average bet-size. An FFFS by BAS-RR interaction effect showed that participants who scored low on both BAS-RR and FFFS had lower bet-sizes compared to the other participants. These findings suggest that conditionability and reinforcement sensitivity play a role in gambling behavior.

Enhancement of Odor Avoidance Regulated by Dopamine Signaling inCaenorhabditis elegans

The enhancement of sensory responses after prior exposure to a stimulus is a fundamental mechanism of neural function in animals. Its molecular basis, however, has not been studied in as much depth as the reduction of sensory responses, such as adaptation or habituation. We report here that the avoidance behavior of the nematode Caenorhabditis elegans in response to repellent odors (2-nonanone or 1-octanol) is enhanced rather than reduced after preexposure to the odors. This enhancement effect of preexposure was maintained for at least 1 h after the conditioning. The enhancement of 2-nonanone avoidance was not dependent on the presence or absence of food during conditioning, which generally functions as a strong positive or negative unconditioned stimulus in the animals. These results suggest that the enhancement is acquired as a type of nonassociative learning. In addition, genetic and pharmacological analyses revealed that the enhancement of 2-nonanone avoidance requires dopamine signaling via D(2)-like dopamine receptor DOP-3, which functions in a pair of RIC interneurons to regulate the enhancement. Because dopamine signaling has been tightly linked with food-related information to modulate various behaviors of C. elegans, it may play different role in the regulation of the enhancement of 2-nonanone avoidance. Thus, our data suggest a new genetic and pharmacological paradigm for nonassociative enhancement of neural responses that is regulated by dopamine signaling.