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In contrast to the conventional view that analysts forecast optimistically, we provide evidence of the Negativity Bias. Analysts show negative forecast bias associated with their relative local inc...

In social interactions, valence-based judgements are an important component of interpersonal distances regulation. Within the framework of the Range-Frequency model, we tested whether the emotional context, which is known to produce a contrast effect on valence ratings, also contributes to the regulation of interpersonal distances. 51 participants divided in two groups were shown virtual characters with either a neutral facial expression (target-stimuli) or an emotional facial expression (contextual stimuli) in two successive sessions (angry then happy emotional context or vice-versa). The participants rated the valence of the virtual characters and judged the appropriateness of different interpersonal distances. For neutral characters, contrast effect of emotional context was observed, albeit only subtly on interpersonal distance judgments. Overall, the data suggest that although the emotional context influences valence-based judgments of social stimuli, it has a parsimonious effect on interpersonal distance regulation, presumably because the latter relies primarily on emotional facial expression categorical-information.

Background Social comparisons between pupils are especially relevant at school. Such comparisons influence self-perception and performance. When pupils evaluate themselves more negatively and perform worse after an upward comparison (with a better off pupil) than a downward comparison (with a worse-off pupil), this is a contrast effect. On the other hand, when they evaluate themselves more positively and are better after an upward than downward comparison, this is an assimilation effect. Aims We examine assimilation and contrast effects of comparison in the classroom on pupils' self-evaluation and performance. Previous work by Fayant, Muller, Nurra, Alexopoulos, and Palluel-Germain (2011) lead us to hypothesize that approach vs. avoidance moderates the impact of upward vs. downward comparison: approach should lead to an assimilation effect on self-evaluation and performance, while avoidance should lead to contrast on self-evaluation and performance. Methods To test this hypothesis, we primed pupils with either approach or avoidance before reading upward or downward comparison information about another pupil. We then measured self-evaluation (Experiment 1) and performance (Experiments 1 and 2). Results Results confirmed our predictions and revealed the predicted interaction on self-evaluation (Experiment 1) and performance (Experiment 2): approach leads to an assimilation effect (in both experiments) whereas avoidance leads to a contrast effect (in Experiment 2). Conclusions These experiments replicate previous studies on self-evaluation and also extend previous work on performance and in a classroom setting. Priming approach before upward comparison seems especially beneficial to pupils.

The subject of this paper is the contrast effect in negotiations from the behavioral economics perspective. We conducted an experimental study using a "divorce litigation game" with complete information about payoffs aimed at testing whether participants are prone to context-dependent decisions. The sample was created by 100 law students from the Faculty of Law of the University of Niš. In a "between subjects" design 100 different participants were tested in the control and treatment group. The main finding is that there is a statistically significant difference between the two groups, thus confirming the presence of the contrast effect. The study opens the door to further real experiments with an emphasis on other subjects, such as lawyers, checking if they are so "rational"

Although a wealth of studies have evidenced successive negative contrast effects in instrumental or operant procedures, relatively few studies have determined if and how a sudden downshift in reward quality alters foraging behaviour. In light of research by ecologists and psychologists in the area of risk-sensitive foraging, this area would serve as an adequate framework to examine the effects of a sudden downshift in reward quality on foraging behaviour. Therefore, the purpose of the current experiment was to explore if and how a sudden downshift in reward quality altered risk-sensitive foraging in rats. Subjects chose between a variable and fixed option that returned the same mean amount of sugar pellets, but one group of subjects (i.e., contrast group) were downshifted from 100% to 20% sugar pellets, whereas an unshifted control group received 20% sugar pellets throughout the study. Consistent with past risk-sensitive foraging research where reward quality was manipulated, subjects in the contrast group displayed significantly more risk-prone choices when reward quality was decreased from 100% to 20% sugar. However, the change in choice was inconsistent with contrast effects observed in prior contrast experiments. In addition to choice behaviour, other behavioural measures (e.g., rejected food, latency to choice) were significantly different between the unshifted control and contrast group and across conditions in the contrast group (e.g., latency to choice and rejected food significantly increased when reward quality changed from 100% to 20% sugar). These findings revealed a contrast effect and were similar to past contrast studies where reward quality was downshifted. Thus, when foragers experience a sudden downshift in reward quality, they may display significant behavioural changes and, in turn, display a bias for patches that yield a greater reward quality despite potentially lower payoffs. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Performance ratings have been shown to be susceptible to various biases. Two of the most influential biases are assimilation and contrast effects. They denote that ratings are biased either toward (assimilation) or away from (contrast) prior reference assessments. Rigorous rater trainings have proven useful to reduce the latter bias, which, however, are rather time‐consuming. A more parsimonious approach achieving a similar purpose may be to optimize the rating material in order to reduce the tendency of being affected by non‐performance‐related information. Behaviorally anchored ratings scales (BARS) appear to be a theoretically sound alternative in contexts in which rater trainings are uncommon or assessment situations occur only rarely. In two experiments, we evaluated whether BARS are able to reduce assimilation and contrast effects using systematically manipulated standardized videotaped selection interviews. While assimilation effects were reduced by 40%, contrast effects were not significantly but descriptively reduced.

Contrary to lay conceptions, unattractive locations can under certain circumstances increase the perceived value of neighboring areas. This phenomenon is akin to a contrast effect. However, extant research on this type of contrast suffers from two limitations. First, the use of repeated measures may inflate the likelihood of observing a contrast effect. Second, there is a lack of meaningful comparisons for gauging the size of the effect. We designed three experiments to address these issues. In each, we assessed how much participants valued places located increasingly far from an unsafe housing block. Participants either rated several target locations or just a single one at a time. We also assessed whether the positiveness of the contrast effect due to the unsafe housing block would be able to compete with the positive effect of a nearby park. The results replicate past findings of a contrast effect in spatial context; they show that the effect generalizes to a different design; and they demonstrate that a contrast effect due to an unattractive location can indeed be as "beneficial" for some neighboring areas as the effect of a genuinely attractive location. (PsycINFO Database Record

When humans and nonhuman animals work hard to achieve a goal, they generally appreciate the results more than when the goal requires little effort to be achieved. The within-trial contrast (WTC) hypothesis explains this phenomenon in terms of the contrast between individuals’ relative hedonic states. We examined the validity of the WTC hypothesis by incorporating an implicit association test (IAT) as a measure of implicit preference in procedures similar to those of Tsukamoto, Kohara, and Takeuchi (Learning & Behavior, 45, 135–146, 2017), who reported emergence of the WTC effect in humans. As a procedural consideration, we also changed the following event to the presentation of a single stimulus instead of a simultaneous discrimination task. We manipulated the effort involved and difficulty of a preceding task by varying the interresponse time (IRT) in differential reinforcement with a low response rate schedule that involved a limited hold. Influences of training were tested in two measures: the choice test and the IAT. Results revealed that in the choice test participants showed significant preference for stimuli that followed the effortful task, which involved a longer IRT even though the effect size was smaller than in the previous study. However, in the IAT, we could not observe the association that the WTC hypothesis presumed. Inconsistency between the choice test and the IAT suggests that preference arising from the WTC paradigm might be caused by a factor other than a change in hedonic state, leaving the question of whether we succeeded in selecting an appropriate measure.

Based on the affective endowment-contrast theory, negative affect (NA) is hypothesized to augment positive affect (PA). Study 1 examined this contrast effect (augment effect) in a laboratory setting. Participants (n = 94) were assigned into positive, negative or neutral affective background conditions through false feedback procedure, and then a same positive stimulus was given to all participants. Results indicated that participants in negative condition experienced more feelings of PA and less NA after receiving the positive stimulus compared to the other two conditions. Study 2 investigated this augment effect under naturalistic context. Participants (n = 150) were classified into high positive, high negative, or mild positive affective background groups based on their naturally occurred affects. Then a positive manipulation was giving to all participants. Results indicated that participants in the high negative group experienced the most decrease in feelings of NA after receiving the positive manipulation. Results from the two studies provided evidence to the endowment-contrast theory, indicating that the valance of positive stimulus was augmented under negative affective background.

Four experiments reveal that actual taste perception and mental simulation of taste can exert a bidirectional contrast effect on each other. Experiment 1 shows that similar to actual taste experience, simulated taste experience is influenced by a prior actual taste in a contrastive manner. Experiment 2 shows that this contrast effect of actual taste on taste simulation occurs only when people adopt an imagery-based rather than an analytical processing mode. Experiment 3 demonstrates the bidirectional nature of the current effect and again shows that it depends on people's use of mental simulation. Lastly, experiment 4 replicates the observed effect in a realistic marketing environment. These findings support the proposition of a simulation-induced adaptation mechanism. Theoretical and practical implications of this research are discussed.

Perception of a sound is influenced by spectral properties of surrounding sounds. When frequencies are absent in a preceding acoustic context before being introduced in a subsequent target sound, detection of those frequencies is facilitated via an auditory enhancement effect (EE). When spectral composition differs across a preceding context and subsequent target sound, those differences are perceptually magnified and perception shifts via a spectral contrast effect (SCE). Each effect is thought to receive contributions from peripheral and central neural processing, but the relative contributions are unclear. The present experiments manipulated ear of presentation to elucidate the degrees to which peripheral and central processes contributed to each effect in speech perception. In Experiment 1, EE and SCE magnitudes in consonant categorization were substantially diminished through contralateral presentation of contexts and targets compared to ipsilateral or bilateral presentations. In Experiment 2, spectrally complementary contexts were presented dichotically followed by the target in only one ear. This arrangement was predicted to produce context effects peripherally and cancel them centrally, but the competing contralateral context minimally decreased effect magnitudes. Results confirm peripheral and central contributions to EEs and SCEs in speech perception, but both effects appear to be primarily due to peripheral processing.

We examined whether enhancing (vs. not enhancing) the emotionality of a referent public good influences the subsequent valuation of a target public good. We predicted that it would and that the directionality of its impact would depend on a fundamental cognitive process - categorisation. If the target and referent goods belong to the same domain, we expected that the effect on the target would be in the same direction as the emotional enhancement of the referent (assimilation effect). However, if the target and referent goods belong to different domains, we expected that the effect on the target would be either negligible or in the opposite direction to that of the emotional enhancement of the referent (null or contrast effect). In Experiment 1 we examined the impact of emotionally enhancing a referent public good on feelings towards a target public good, whereas in Experiment 2 on the willingness to contribute towards a target public good. The results support the predicted interaction, which was driven by an assimilation effect for same-domain goods and a null effect for different-domain goods. In doing so, the present findings highlight the interplay between cognition and emotion in the valuation of public goods. We discuss theoretical and practical implications.

Food texture plays an important role in the experience of food. Researchers have proposed various methods to manipulate the perception of food texture using auditory and physical stimulation. In this paper, we demonstrate a system to present visually modified mastication movements in real-time to manipulate the perception of food texture, because visual stimuli efficiently work to enrich other food-related perceptions and showing someone their deformed posture changes somatosensory perception. The result of our experiments suggested that adding real-time feedback of facial deformation when participants open their mouths can increase the perceived chewiness of foods. Moreover, perceptions of hardness and adhesiveness were improved when the participants saw their modified face or listened to their non-modified chewing sound, while both perceptions were decreased when participants were presented with both stimuli. These results indicate the occurrence of the contrast effect.

Orientation contrast is formed when some elements orient differently from their surroundings. Although orientation contrast can be processed in the absence of top-down attention, the underlying neural mechanism for this automatic processing in humans is controversial. In particular, whether automatic detection of orientation contrast occurs at the initial feedforward stage in the primary visual cortex (i.e., V1) remains unclear. Here, we used event-related potentials (ERPs) to examine the automatic processing of orientation contrast in humans. In three experiments, participants completed a task at fixation while orientation contrasts were presented in the periphery, either in the upper visual field (UVF) or the lower visual field (LVF). All experiments showed significant positive potentials evoked by orientation contrasts over occipital areas within 100 ms after stimulus onset. These contrast effects occurred 10–20 ms later than the C1 components evoked by identically located abrupt onset stimuli which indexes the initial feedforward activity in V1. Compared with those in the UVF, orientation contrasts in the LVF evoked earlier and stronger activities, probably reflecting a LVF advantage in processing of orientation contrast. Even when orientation contrasts were rendered almost invisible by backward masking (in Experiment 2), the early contrast effect in the LVF was not disrupted. These findings imply that automatic processing of orientation contrast could occur at early visual cortical processing stages, but was slightly later than the initial feedforward processing in human V1; such automatic processing may involve either recurrent processing in V1 or feedforward processing in early extrastriate visual cortex. Highlights -We examined the earliest automatic processing of orientation contrast in humans with ERPs.-Significant orientation contrast effect started within 100 ms in early visual areas.-The earliest orientation contrast effect occurred later than the C1 evoked by abrupt onset stimuli.-The earliest orientation contrast effect was independent of top-down attention and awareness.-Automatic detection of orientation contrast arises slightly after the initial feedforward processing in V1.

Humans' judgment of relative-frequency, similar to their use of probability in decision-making, is often distorted as an inverted-S-shape curve-small relative-frequency overestimated and large relative-frequency underestimated. Here we investigated how the judgment of relative-frequency, despite its natural reference points (0 and 1) and stereotyped distortion, may adapt to the environmental statistics. The task was to report the relative-frequency of black (or white) dots in a visual array of black and white dots. We found that participants' judgment was distorted in the typical inverted-S-shape, but the distortion curve was influenced by both the central tendency and spread of the distribution of objective relative-frequencies: the lower the central tendency, the higher the overall judgment (contrast effect); the higher the spread, the more curved the inverted-S-shape (curvature effect). These context effects are in the spirit of efficient coding but opposite to what would be predicted by Bayesian inference. We further modeled the context effects on the level of individual trials, through which we found not only a trial-by-trial adaptation, but also the non-linear sequential effects that were recently reported mainly in circularly distributed visual stimuli.

Adaptive decision making relies on learning from feedback. Because feedback sometimes can be misleading, optimal learning requires that knowledge about the feedback's reliability be utilized to adjust feedback processing. Although previous research has shown that feedback reliability indeed influences feedback processing, the underlying mechanisms through which this is accomplished remain unclear. Here we propose that feedback processing is adjusted by the adaptive, top-down valuation of feedback. We assume that unreliable feedback is devalued relative to reliable feedback, thus reducing the reward prediction errors that underlie feedback-related brain activity and learning. A crucial prediction of this account is that the effects of feedback reliability are susceptible to contrast effects. That is, the effects of feedback reliability should be enhanced when both reliable and unreliable feedback are experienced within the same context, as compared to when only one level of feedback reliability is experienced. To evaluate this prediction, we measured the event-related potentials elicited by feedback in two experiments in which feedback reliability was varied either within or between blocks. We found that the fronto-central valence effect, a correlate of reward prediction errors during reinforcement learning, was reduced for unreliable feedback. But this result was obtained only when feedback reliability was varied within blocks, thus indicating a contrast effect. This suggests that the adaptive valuation of feedback is one mechanism underlying the effects of feedback reliability on feedback processing.

The contrast effect of attractiveness was tested with avatars and a photograph.Attractive avatar exposure led to lower attractiveness ratings of the photograph.Exposure to unattractive avatars led to higher attractiveness ratings.Evidence for the contrast effect comparing computer-generated stimuli and humans. Kenrick and Gutierres (1980) found that participants exposed to attractive women would later rate an average-looking woman as less attractive compared to participants who had not been exposed to the attractive women. Because of the increase in our use of technology and computer programs utilizing avatars, two experiments were conducted to determine whether this contrast effect would occur when participants were presented with attractive avatars. Participants were told that they were in a study interested in first impressions and they were asked to rate images on a number of characteristics, including attractiveness. In Experiment 1, participants were presented with either three attractive or three unattractive avatars and then one photograph of an average-looking woman. In Experiment 2, participants were presented with either three attractive or three unattractive male or female avatars and rated a photograph of a man or woman, respectively. In both experiments, participants exposed to the attractive avatars rated the woman as significantly less attractive compared to the participants exposed to the unattractive avatars.

Social interactions/situations have dramatic influences on motivation. Creating animal models examining these influences promotes a better understanding of the psychological and biological underpinnings of social motivation. Rodents are sensitive to social history/experience during associative conditioning and food-sharing tasks. Would reward-oriented operant behavior be sensitive to social influences by showing a negative contrast-like effect when another organism obtains a greater value outcome? We used a side-by-side arrangement of operant response chambers wherein one animal obtained consistently high reward signaled by a discrete cue. The neighboring, experimental rat experienced different combinations of high and low reward trial sequences. Control conditions included distraction from a conspecific in the neighboring chamber (rat distractor) or cue/food dispenser operating without a conspecific (program distractor) in addition to testing subjects alone. Results support an influence of the other animal actively performing the task on the experimental subject's behavior. Primarily, responding was significantly slower for the low reward trials while the neighboring rat was receiving the higher magnitude reward. The lever-press and not food-cup retrieval latency was significantly slower during exposure to a conspecific neighbor performing the operant task. The effect was not obtained in all session sequences and was more pronounced using longer series of consecutive low reward trials. The slowing effect was also obtained with the program-distractor experience in a different trial sequence. These findings suggest a social-induced negative incentive contrast effect in rats possibly mediated by an outcome inequity process that could have key similarities to complex situational-affective effects on motivation involving frustration or jealously.

People sometimes say they are ‘moved’ or ‘touched’ by something. Although the experience is familiar to most, systematic research on being moved has just begun. The current research aims to advance our understanding of the prototypical elicitors of being moved. We tested the hypothesis that being moved is elicited by core values (i.e., values that are particularly central to being human) that manifest themselves in circumstances that are unfavourable to their emergence. In three experiments, two with text stimuli and one with pictorial stimuli, we found compelling evidence that the same core value (e.g., love, willpower, beauty) is perceived as more moving when it emerges in unfavourable than in favourable circumstances. The effect was found in both males and females, although stronger in the latter group, and across all investigated core values, although love was generally more moving than other core values. The theoretical and practical significance of these findings is discussed.

In the literature on psychophysics, it is reported that during a psychophysical experiment when a user is subjected to many trials in succession, the perception of the current trial is observed to be overly similar to the previous trial (assimilation effect), and is observed to be dissimilar to distantly past trials (contrast effect). Overall, this behavior is called the sequential effect and is a very well-established phenomenon in psychophysics. In the literature, the sequential effect has been demonstrated on loudness of sound, and has been further assumed for other perceptual modalities like haptics and vision. However, to the best of our knowledge, we have not found any experimental study either claiming its existence for kinesthetic perception or for quantifying the effect. This motivates us to study the sequential effect on kinesthetic perception. In this chapter, we take up this study and find out whether or not the sequential effect exists, and how to quantify the effect. In order to study the presence of sequential effect for kinesthetic perception, we design an experimental setup where a user is subjected to a series of random force stimuli. We record the responses for several users. Thereafter, a logistic regression model is employed to observe how much the recorded responses are affected by the past stimuli. Based on the results of the logistic regression model, we demonstrate the presence of sequential effect for the kinesthetic stimuli. We also explain how to quantify the duration over which the sequential effect persists.

Reactivity to a reward is affected by prior experience with different reinforcer values of that reward, a phenomenon known as incentive relativity. Incentive relativity can be studied via the consummatory successive negative contrast (cSNC) paradigm, in which acceptance of 4% sucrose is assessed in animals that had been exposed to 32% sucrose. These downshifted animals usually exhibit significantly less sucrose acceptance than animals that always received the 4% sucrose solution. In previous work, we found that exploration of a novel open field (OF) before the first trial with the downshifted solution attenuated the contrast effect. The goal of the present experiments was to expand the knowledge on the effects of OF exposure on cSNC. We evaluated the effect OF exposure before the second downshift trial and assessed the mediational role of the adrenergic system in the effects of OF during the first and second trial of cSNC. The results indicate that OF applied before the first or second downshift trials exert opposite effects and that the adrenergic system is involved in the acquisition and consolidation of the OF information. Fil: Justel, Nadia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Psyrdellis, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina Fil: Pautassi, Ricardo Marcos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra. Universidad Nacional de Córdoba. Instituto de Investigación Médica Mercedes y Martín Ferreyra; Argentina Fil: Mustaca, Alba Elisabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Médicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Universidad Abierta Interamericana; Argentina