Emotional eating and Pavlovian learning: evidence for conditioned appetitive responding to negative emotional states

Appetitive learning has been demonstrated several times using neutral cues or contexts as a predictor of food intake and it has been shown that humans easily learn cued desires for foods. It has, however, never been studied whether internal cues are also capable of appetitive conditioning. In this study, we tested whether humans can learn cued eating desires to negative moods as conditioned stimuli (CS), thereby offering a potential explanation of emotional eating (EE). Female participants were randomly presented with 10 different stimuli eliciting either negative or neutral emotional states, with one of these states paired with eating chocolate. Expectancy to eat, desire to eat, salivation, and unpleasantness of experiencing negative emotions were assessed. After conditioning, participants were brought into a negative emotional state and were asked to choose between money and chocolate. Data showed differential conditioned responding on the expectancy and desire measures, but not on salivation. Specific conditioned effects were obtained for participants with a higher BMI (body mass index) on the choice task, and for participants high on EE on the unpleasantness ratings. These findings provide the first experimental evidence for the idea that negative emotions can act as conditioned stimuli, and might suggest that classical conditioning is involved in EE.     

Manipulating self-efficacy in the exercise environment in women: influences on affective responses.

Self-efficacy was experimentally manipulated in an exercise context, and its effect on affective responses was examined. College women (N = 46) were randomly assigned to a high- or low-efficacy condition, and efficacy expectations were manipulated by means of bogus feedback and graphs depicting contrived normative data. The manipulation successfully influenced affective responses, with participants in the high-efficacy group reporting more positive and less negative affect than did the low-efficacy group. Efficacy was significantly related to feeling-state responses during and after activity but only in the high-efficacy condition. The results suggest that self-efficacy can be manipulated and that these changes are related to the affective experience associated with exercise. Such findings may have important implications for the roles played by self-efficacy and affect in exercise adherence.     

状态焦虑对时距知觉的影响：认知评价和注意偏向有调节的中介作用

探讨状态焦虑对时距知觉的影响以及注意偏向与认知评价在其中的中介和调节作用。招募大学生60人, 随机分为高、低状态焦虑组, 用情绪诱导程序诱导高、低状态焦虑; 用点探测范式测量注意偏向; 用时间再现任务测量时距知觉; 用视觉模拟心境量表测量认知评价。结果发现：(1)状态焦虑会导致对2000 ms时距的高估; (2)注意偏向在状态焦虑对2000 ms时距知觉的影响中具有部分中介作用; (3)状态焦虑通过注意偏向影响时距知觉的中介过程受到认知评价的调节作用：只有当认知评价得分较高时, 即个体认为焦虑对心理健康有害程度较高时, 状态焦虑通过注意偏向影响2000 ms时距知觉。研究结果揭示了焦虑个体时距知觉的内部过程, 丰富了焦虑通过注意偏向影响时距知觉的解释视角, 为通过认知评价和注意偏向的调整改善焦虑个体时距偏差现象提供了重要参考。     

积极情绪促进对积极刺激注意偏向：投入与抽离

一系列研究结果被认为反映了积极情绪促进投入注意至积极刺激的偏向。然而,由于所使用的范式不能分离对积极刺激的注意投入偏向和抽离偏向,这些研究结果也可能反映了积极情绪促进从积极刺激抽离注意更少的偏向。本研究采用音乐聆听和事件回忆唤起被试的积极或中性情绪,随后要求被试完成点探测范式的变式任务,通过中性-中性条件与一致条件的反应时之差测量投入偏向,以及不一致条件与中性-中性条件的反应时之差测量抽离偏向,探讨积极情绪究竟促进投入偏向,还是促进抽离偏向。结果表明：（1）相比中性组,积极情绪组并没有表现出更大的中性-中性条件和一致条件的反应时之差。这说明,积极情绪没有促进投入注意至积极刺激的偏向;（2）相比中性情绪组,积极情绪组的不一致条件与中性-中性条件的反应时之差更大。这说明,积极情绪促进从积极刺激抽离注意更少的偏向。由此,积极情绪并不促进投入注意至积极刺激的偏向,而是促进对积极刺激的抽离偏向。     

The effects of attention retraining on depressive mood and cortisol responses to depression‐related stimuli1

Although it has been reported that attentional bias at an early stage is found in depression, no study has investigated the effects of modification of attentional bias at an early stage on depressive mood and cortisol response to a stressor. Therefore, this study tested the hypotheses that the modification of attentional bias at an early stage would reduce depressive mood and cortisol response. Fifty‐three participants were allocated alternately either to the training or the control group. They were administered attention retraining for modification of attentional bias or a sham attention task, and then underwent a stress task. With respect to depressive mood response, depressive mood increased in response to a stress task in the control group, while for high‐dysphoric participants in the training group, depressive mood response remained constant. These results indicate that attention retraining is efficacious for reducing depressive mood response. With respect to cortisol response, the percentage change in cortisol is associated with the amount of change in the attentional bias index scores. The results suggest the possibility that attention retraining could reduce cortisol response.     

Attentional biases for threat after fear-related autobiographical recall

Background : Previous studies suggested that affective state could enhance stimulus salience and modulate attention allocation for mood-congruent information, but contrasting data have been reported on the effects of mood induction on attentional biases for threat (ABTs) in non-clinical individuals.

Objective : We aimed to assess whether laboratory-induced negative mood can increase individuals’ tendency to allocate attention on threatening stimuli, thus determining a difficulty in attentional disengagement from threat. We also aimed at assessing whether level of trait anxiety could modulate the effect of mood induction on attentional biases.

Methods : We used an autobiographical episode recall procedure for mood induction (fear, happiness and neutral episode recall), and an exogenous cueing task with threatening and non-threatening images to assess attentional biases in 120 undergraduate students.

Results: Participants showed a significant difficulty in disengaging attention from threat after recalling fear-related episodes, independently from their trait anxiety level.

Conclusions: These findings clarify that the ABTs are not exclusive to anxiety disorders or high trait anxiety individuals, and could also arise in non-clinical individuals in a fearful context.     

Signaling and affective functions of conditioned aversive stimuli in an appetitive choice discrimination: US intensity effects

Different groups of rats received Pavlovian aversive conditioning in which US-shock intensity (0.25–1.0 mA) and CS-US correlation (+, 0, ?) were factorially varied. Then, the CS was administered for each group contingent upon the reinforced response in an appetitive choice discrimination. Absolute and ratio measures of speed of running in the presence of the CS showed that, at the start of discrimination training, CS+ suppressed and CS- facilitated performance. However, later in training but prior to any evidence of choice learning, these speed effects reversed, with the magnitude of both the initial and reversed effects being a positive function of US intensity. Consistent with the reversal of speeds, associative (choice) measures showed that CS+ facilitated and CS- retarded discrimination learning relative to CSo and, within limits, these effects were also amplified by stronger USs. The findings suggest that a CS has both affective (motivational) and signaling (associative) functions and that both are influenced by US intensity; however, the CS's affective property is rapidly extinguished in the presence of a hedonicly different reinforcer, while leaving the CS's signaling property largely intact. Hence, the CS functions as a transformed signal for the new (appetitive) reinforcer and facilitates or retards learning by mediating the reinforcer's presence (CS+) or absence (CS-).     

Extinction of appetitive learning is disrupted by cycloheximide and propranolol in the sand maze in rats

The present study investigated whether memory for extinction in an appetitive task (the sand maze) could be attenuated by administration of cycloheximide (protein synthesis inhibitor) or propranolol (β-adrenergic receptor antagonist). Ninety-day-old male Long-Evans rats were trained to retrieve a sweet cereal reinforcer from an open container in the sand maze. One day following this non-spatial training, rats received three extinction trials in which they were placed in the maze with the reinforcer present, but unattainable. Thirty minutes prior to the first extinction trial, rats received an intraperitoneal injection of cycloheximide (1mg/kg), propranolol (25mg/kg), or vehicle (1mg/kg distilled water). Twenty-four hours later, rats were tested in the sand maze with the reinforcer again available. Results from the test trial showed that both cycloheximide and propranolol groups found the reinforcer more quickly than controls. Two weeks later, rats were trained on a spatial version of the sand maze in which they had to search for a buried reinforcer using extramaze cues. Cycloheximide and propranolol groups learned this task significantly faster than the control group, demonstrating the long-lasting effect of cycloheximide and propranolol on the blocking of memory for extinction.     

Individual differences in the impact of attentional bias training on cardiovascular responses to stress in women

Abstract

Experimental studies show that training people to attend to negative stimuli makes them more likely to respond with greater anxiety to stress. The present study investigated this effect in students using measures of cardiovascular responses to stress and examined whether individual differences influence the impact of attention training on stress responses. Using a standard dot probe task, 30 participants underwent negative attentional bias training and 34 participants underwent anti-negative training before completing a stressful speech task. Results indicated that, overall, participants exhibited acclimatization to the procedures (indicated by a dip in blood pressure post-training) and normal stress responding (indicated by elevated blood pressure in response to stress; p<.001). However, consideration of participants’ scores for neuroticism/emotional-stability revealed important differences in how the intervention impacted on cardiovascular profiles (p=.008). For participants with high neuroticism scores, the negative attentional bias intervention elicited more exaggerated stress responding than the anti-negative intervention. For those with low neuroticism scores (i.e., emotionally stable participants), the anti-negative intervention was associated with elevated post-intervention blood pressure and higher blood pressure reactivity to stress. These findings provide evidence of the impact of attentional bias manipulation on physiological stress reactivity and suggest the effect is highly contingent on individual temperaments.     

Development and psychometric validation of the verbal affective memory test

We here present the development and validation of the Verbal Affective Memory Test-24 (VAMT-24). First, we ensured face validity by selecting 24 words reliably perceived as positive, negative or neutral, respectively, according to healthy Danish adults’ valence ratings of 210 common and non-taboo words. Second, we studied the test's psychometric properties in healthy adults. Finally, we investigated whether individuals diagnosed with Seasonal Affective Disorder (SAD) differed from healthy controls on seasonal changes in affective recall. Recall rates were internally consistent and reliable and converged satisfactorily with established non-affective verbal tests. Immediate recall (IMR) for positive words exceeded IMR for negative words in the healthy sample. Relatedly, individuals with SAD showed a significantly larger decrease in positive recall from summer to winter than healthy controls. Furthermore, larger seasonal decreases in positive recall significantly predicted larger increases in depressive symptoms. Retest reliability was satisfactory, rs?≥?.77. In conclusion, VAMT-24 is more thoroughly developed and validated than existing verbal affective memory tests and showed satisfactory psychometric properties. VAMT-24 seems especially sensitive to measuring positive verbal recall bias, perhaps due to the application of common, non-taboo words. Based on the psychometric and clinical results, we recommend VAMT-24 for international translations and studies of affective memory.     

赌博障碍的认知功能缺陷及神经基础

赌博障碍是指持续且反复的赌博行为,给个人、家庭和社会都带来了严重后果,近年来受到越来越多研究者的关注。本研究总结了赌博障碍的认知功能缺陷及其神经基础,主要集中在如下四个方面：①认知扭曲、②奖赏和惩罚敏感性、③注意偏向和④决策。未来研究应多从认知神经科学角度深入探究赌博障碍的发生机制和发展过程,关注大脑结构变化及功能网络改变,并将其整合到一个统一的神经生物机制框架中,找到更加有效的干预和治疗手段。     

赌博障碍的认知功能缺陷及神经基础

赌博障碍是指持续且反复的赌博行为,给个人、家庭和社会都带来了严重后果,近年来受到越来越多研究者的关注。本研究总结了赌博障碍的认知功能缺陷及其神经基础,主要集中在如下四个方面：①认知扭曲、②奖赏和惩罚敏感性、③注意偏向和④决策。未来研究应多从认知神经科学角度深入探究赌博障碍的发生机制和发展过程,关注大脑结构变化及功能网络改变,并将其整合到一个统一的神经生物机制框架中,找到更加有效的干预和治疗手段。     

Looking into your eyes: observed pupil size influences approach-avoidance responses

The eyes reveal important social messages, such as emotions and whether a person is aroused and interested or bored and fatigued. A growing body of research has also shown that individuals with large pupils are generally evaluated positively by observers, while those with small pupils are perceived negatively. Here, we examined whether observed pupil size influences approach-avoidance tendencies. Participants performed an Approach-Avoidance Task using faces with large and small pupil sizes. Results showed that pupil size influences the accuracy of arm movements. Specifically, individuals were less prone to approach a face with small pupils than a face with large pupils. Conversely, participants were less prone to avoid a face with large pupils than a face with small pupils. Collectively, these findings suggest that perceivers attend to a facial cue – pupil size – when interacting with others.     

On the experience of self-relevant feedback: How self-concept organization influences affective responses and self-evaluations

We evaluated how self-concepts are represented in memory, testing predictions about how self-relevant feedback influences mood and self-evaluation. Specifically, we view the self as comprised of multiple self-aspects (e.g., daughter, sorority sister), each associated with specific attributes (e.g., shy, philanthropy). Study 1 showed that priming a self-aspect increased the accessibility of attributes idiosyncratically associated with the activated self-aspect. In Studies 2 and 3, positive or negative self-relevant feedback was provided to observe how affect and self-evaluations are mediated by self-concept representation. Study 2 demonstrated that changes in mood were accounted for by how feedback impacted evaluations of the currently activated self-aspect. Moreover, evaluations of other self-aspects shifted as they shared more attributes with the self-aspect implicated by feedback. In Study 3, feedback about an attribute also influenced affect, with stronger mood change revealed for attributes associated with a greater proportion of self-aspects. This work demonstrates that affective experiences resulting from self-relevant feedback are not determined by one’s self-concept representation in its entirety, but rather, by the impact of that feedback on activated self-aspects.     

Expectancy-learning and evaluative learning in human classical conditioning: affective priming as an indirect and unobtrusive measure of conditioned stimulus valence

It has been argued that in classical conditioning two processes might be operative. First, one may learn that the conditioned stimulus (CS+) is a valid predictor for the occurrence of the biologically negative or positive event (US; expectancy-learning). Second, one may learn to perceive the conditioned stimulus itself as a negative or positive stimulus, depending on the valence of the event it has been associated with (evaluative learning). Until the present, however, both forms of learning have been investigated using rather different conditioning procedures. Using a differential aversive conditioning preparation with pictures of human faces as CSs and an electrocutaneous stimulus as US, we were able to demonstrate that both forms of learning can co-occur. Moreover, the extent of evaluative learning in this aversive conditioning procedure did not significantly differ from the amount of evaluative learning in an evaluative conditioning procedure with positive and negative adjectives as USs, which was administered to the same participants. In the present study evaluative learning was not only indexed by direct evaluative ratings, but we introduced affective priming as an indirect and unobtrusive, reaction time based measure of stimulus valence. Finally, imagery instructions during acquisition did not facilitate expectancy-learning nor evaluative learning.     

状态焦虑对回溯式时距判断的影响：认知评价和记忆偏向有调节的中介作用

探讨状态焦虑对回溯式时距判断的影响, 并检测记忆偏向与认知评价在其中的中介和调节作用。实验1招募大学生60人, 随机分为高、低状态焦虑组, 采用情绪诱导程序诱导高、低状态焦虑; 采用口头估计任务测量回溯式时距判断, 考察高、低状态焦虑诱导后的回溯式时距判断差异。实验2在实验1的基础上, 招募大学生60人, 增加自由回忆任务测量记忆偏向, 考察状态焦虑对回溯式时距判断的影响中记忆偏向的中介作用。实验3在实验1和实验2的基础上, 招募大学生90人, 增加视觉模拟心境量表测量认知评价, 考察状态焦虑对回溯式时距判断的影响, 并检测认知评价与记忆偏向在其中的作用。结果发现：(1)在回溯式时距判断中, 高状态焦虑比低状态焦虑更高估时距; (2)在状态焦虑对回溯式时距判断的影响中, 记忆偏向具有中介作用; (3)在状态焦虑对回溯式时距判断的影响中, 认知评价和记忆偏向存在有调节的中介作用：只有当认知评价得分较低时, 即对于认为焦虑对身体健康有害程度较低的个体而言, 在状态焦虑影响回溯式时距判断中, 记忆偏向具有完全中介作用, 即状态焦虑只通过记忆偏向影响回溯式时距判断。研究结果揭示了焦虑个体回溯式时距判断的内部过程, 验证了注意闸门模型中有关用于计时的记忆资源越多对于时距越高估的假设, 丰富了焦虑通过记忆偏向影响回溯式时距判断的解释视角, 为通过调整认知评价改善焦虑个体时距偏差提供了重要参考。     

Using emotional cues in a discrimination learning task: Effects of trait emotional intelligence and affective state

Individuals may differ in their ability to learn the significance of emotional cues within a specific context. If so, trait emotional intelligence (EI) may be associated with faster cue learning. This study (N = 180) tested whether trait EI predicts faster learning of a critical cue for discriminating “terrorists” from “non-terrorists”, using virtual-reality heads as stimuli. The critical cue was either facial emotion (positive or negative), or a neutral feature (hat size). Cognitive ability and subjective state were also assessed. Participants were faster to learn with an emotive cue. Surprisingly, high trait EI was correlated with poorer performance, especially early in learning. Subjective distress was also associated with impaired learning to emotive cues.     

Exposure to a novel context after extinction causes a renewal of extinguished conditioned responses: Implications for the treatment of fear

Renewal gives an experimental model for the relapse of fear symptoms following exposure therapy. While renewal of extinguished fear in humans has been observed following a return to the original context in which fear was acquired (ABA design), it has been more difficult to show upon presentation of a novel context (ABC design). The present experiment used a particularly strong context manipulation in a fear conditioning procedure. Context was manipulated by using large photographs of real environments taken from various angles and was present throughout the entire experiment. A renewal of cognitive expectancy was found in both ABA and ABC renewal designs, although it was larger in the former than in the latter. Response times in making the expectancy judgments increased when there was a change to a new context. The results demonstrate consistency in fear renewal effects between human and animal studies and suggest that relapse following exposure therapy via renewal remains a danger when people encounter a previously feared object in a novel context.