Subjective Valence Research Articles

Neural processing of food and emotional stimuli in adolescent and adult anorexia nervosa patients.

BackgroundA constant preoccupation with food and restrictive eating are main symptoms of anorexia nervosa (AN). Imaging studies revealed aberrant neural activation patterns in brain regions processing hedonic and reward reactions as well as–potentially aversive–emotions. An imbalance between so called “bottom-up” and “top-down” control areas is discussed. The present study is focusing on neural processing of disease-specific food stimuli and emotional stimuli and its developmental course in adolescent and adult AN patients and could offer new insight into differential mechanisms underlying shorter or more chronic disease.Methods33 adolescents aged 12–18 years (15 AN patients, 18 control participants) and 32 adult women (16 AN patients, 16 control participants) underwent functional magnetic resonance imaging (fMRI, 3T high-field scanner) while watching pictures of high and low-calorie food and affective stimuli. Afterwards, they rated subjective valence of each picture. FMRI data analysis was performed using a region of interest based approach.ResultsPictures of high-calorie food items were rated more negatively by AN patients.Differences in activation between patients and controls were found in “bottom up” and “top down” control areas for food stimuli and in several emotion processing regions for affective stimuli which were more pronounced in adolescents than in adults.ConclusionA differential pattern was seen for food stimuli compared to generally emotion eliciting stimuli. Adolescents with AN show reduced processing of affective stimuli and enhanced activation of regions involved in “bottom up” reward processing and “top down” control as well as the insula with regard to food stimuli with a focus on brain regions which underlie changes during adolescent development. In adults less clear and less specific activation differences were present, pointing towards a high impact that regions undergoing maturation might have on AN symptoms.

A Vibrotactile Alarm System for Pleasant Awakening.

There has been a vast development of personal informatics devices combining sleep monitoring with alarm systems, in order to find an optimal time to awaken a sleeping person in a pleasant way. Most of these systems implement auditory feedback, which is not always pleasant and may disturb other sleepers. We present an adaptive alarm system that detects sleeping cycles and triggers alarm signal during shallow sleep, to minimize sleep inertia. Since tactile sensation is associated with positive valence, vibrotactile stimulation is investigated as a silent alarm to enhance pleasant awakening. Three modulation techniques to render the tactile stimuli for pleasant awakening are considered, namely simultaneous, continuous, and successive stimulation. Two experimental studied are conducted. Experiment 1 studied exogenous attention towards tactile stimulation in a multimodal scenario (involving visual and haptic interactions) with fully awake individuals. Results from the attention task and the subjective valence rating suggest that the vibrotactile stimulation should be based on the continuous modulation, since this not only is very perceivable but also associated with positive attention. Experiment 2 evaluated the user experience with tactile stimulation patterns during sleep. Results confirmed the findings of experiment 1. Continuous modulation was rated highest for pleasant yet arousing sleep-awake transition.

Neurophysiological responses during cooking food associated with different emotions

Neurophysiological correlates of affective experience could potentially provide continuous information about a person’s experience when cooking and tasting food, without explicitly verbalizing this. Such measures would be helpful to understand people’s implicit food preferences and choices. This study examined for the first time the relation between neurophysiological variables and affective experiences under real cooking and tasting circumstances, using ingredients that were a priori expected to evoke different affective reactions. 41 participants cooked and tasted two stir-fry dishes in random order following an identical, strictly timed protocol. Once the main ingredient was chicken and the other time mealworms. EEG, ECG and skin potential were recorded continuously. Participants scored subjective valence and arousal after each cooking and tasting session. Frontal EEG alpha asymmetry showed the expected effect throughout the whole cooking and tasting session, consistent with ‘approach’ motivation for chicken and ‘avoidance’ for mealworms. Skin potential effects differed between cooking intervals but were in the expected direction. ECG variables showed an interaction with order of cooking the different dishes. Based on EEG alpha asymmetry, ECG and skin potential variables, we can estimate with 82% accuracy whether a single participant is preparing a dish with mealworms or with chicken. Our study provides evidence that it is possible to estimate experienced emotion during real-life cooking and tasting. We argue that it is important to consider that different neurophysiological and subjective measures reflect different underlying affective processes, to map them out more precisely, and to take advantage of these differences.

Affective Responses in Different Stages of Anorexia Nervosa: Results from a Startle-reflex Paradigm.

There is an evolving debate about pathological affective responses in patients with anorexia nervosa (AN). We examined startle responses in different stages of AN. We applied a startle reflex paradigm with standardized visual stimuli (International Affective Pictures System; food and body pictures) in 64 female participants (17 acute AN, 16 chronically ill AN, 15 long-term recovered AN, 16 healthy controls). We measured subjective ratings of valence and anxiety, and electromyographic startle responses. Participants with acute and chronic AN displayed the same subjective valence ratings to affective stimuli but showed less startle reactivity to affective pictures (F(6, 116) = 2.75, p = .02) compared with healthy control. Food pictures were rated as more unpleasant and higher anxiety provoking by currently ill AN (F(3, 59) = 3.32, p=.03). We observed diverging subjective and psychophysiological reactions in different stages of AN. Psychophysiological methods can help to attain a more comprehensive understanding of biological alterations in the long-term course of AN. Copyright © 2017 John Wiley & Sons, Ltd and Eating Disorders Association.

The effect of social feedback and social context on subjective affective responses to music

Previous research suggests that music listening influences individual affective responses. However, there is scant research examining how social factors might interact to influence subjective affective responses to music. This study investigates the effects of social feedback and social context on subjective affective responses to music. In a between-subjects experiment, participants (N = 120) listened to unfamiliar music from various genres either alone or with another participant. For each musical example, participants received positive and negative social feedback, derived from a pilot study, or factual album information. After listening to each musical example and reading the provided social feedback or album information, participants reported their subjective valence, arousal, subjective affective intensity, concentration, music liking and familiarity. There was no effect of social feedback on subjective valence responses. Positive and negative social feedback influenced subjective arousal responses positively and negatively, respectively. Subjective affective intensity was not influenced by social feedback. Social context did not influence subjective affective responses to the musical examples. Lower concentration was reported in social listening conditions compared to solitary conditions. Greater familiarity with the musical examples was reported when social feedback was provided. The findings of the present study suggest that social feedback can influence particular affective responses to, and familiarity with, music. However, social listening might reduce concentration, especially in the absence of social feedback. These findings highlight issues warranting consideration for how music is affectively experienced in everyday life, as well as purposely used in varied contexts.

Subjective Lexical Characteristics: Comparing Ratings of Members of the Target Population and Doctors for Words Stemming from a Medical Context

The present study investigated the subjective lexical characteristics of words stemming from a medical context by comparing estimations of the target population (age range = 46-89) and of doctors. A total of 58 members of the target population and 22 oncologists completed measures of subjective frequency and emotional valence for words previously collected in interviews of announcement of cancer diagnosis. The members of the target population also completed tests of word definitions, without and within context. As expected, most of the words were rated less familiar, more negative and as generating more intense emotions to the target population than to the doctors. Moreover, only a few words were correctly defined by the target population. Adding a context helped the participants to define most of the words correctly. Importantly, we identified words that were rated familiar by the patients although they did not know their exact meaning. Overall, these results highlight the importance of taking into account the subjective lexical characteristics of words used in specific contexts.

Learning Control Over Emotion Networks Through Connectivity-Based Neurofeedback.

Most mental functions are associated with dynamic interactions within functional brain networks. Thus, training individuals to alter functional brain networks might provide novel and powerful means to improve cognitive performance and emotions. Using a novel connectivity-neurofeedback approach based on functional magnetic resonance imaging (fMRI), we show for the first time that participants can learn to change functional brain networks. Specifically, we taught participants control over a key component of the emotion regulation network, in that they learned to increase top-down connectivity from the dorsomedial prefrontal cortex, which is involved in cognitive control, onto the amygdala, which is involved in emotion processing. After training, participants successfully self-regulated the top-down connectivity between these brain areas even without neurofeedback, and this was associated with concomitant increases in subjective valence ratings of emotional stimuli of the participants. Connectivity-based neurofeedback goes beyond previous neurofeedback approaches, which were limited to training localized activity within a brain region. It allows to noninvasively and nonpharmacologically change interconnected functional brain networks directly, thereby resulting in specific behavioral changes. Our results demonstrate that connectivity-based neurofeedback training of emotion regulation networks enhances emotion regulation capabilities. This approach can potentially lead to powerful therapeutic emotion regulation protocols for neuropsychiatric disorders.

Human Amygdala Represents the Complete Spectrum of Subjective Valence.

Our findings elucidate the mechanisms of affective processing in the amygdala by demonstrating that this brain region represents the entire valence dimension from pleasant to unpleasant. An important implication of this unidimensional valence code is that pleasant and unpleasant valence cannot coexist in the amygdale because overlap of fMRI ensemble patterns for these two valence extremes obscures their unique content. This functional architecture, whereby subjective valence maps onto a pattern continuum between pleasant and unpleasant poles, offers a robust mechanism by which context, expectation, and experience could alter the set-point for valence-based behavior. Finally, identification of spatial and temporal differentiation of valence in amygdala may shed new insights into individual differences in emotional responding, with potential relevance for affective disorders.

Motivational intensity modulates the effects of positive emotions on set shifting after controlling physiological arousal

Recent research on the construct of emotion suggests the integration of a motivational dimension into the traditional two-dimension (subjective valence and physiological arousal) model. The motivational intensity of an emotional state should be taken into account while investigating the emotion-cognition relationship. This study examined how positive emotional states varying in motivational intensity influenced set shifting, after controlling the potential confounding impacts of physiological arousal. In Experiment 1, 155 volunteers performed a set-shifting task after being randomly assigned to five states: high- vs. low-motivating positive affect (interest vs. serenity), high- vs. low-motivating negative affect (disgust vs. anxiety), and neutral state. Eighty-five volunteers participated in Experiment 2, which further examined the effects of higher vs. lower degree of interest. Both experiments measured and compared participants' physiological arousal (blood pressure and pulse rate) under the normal and experimental conditions as the covariate. Results showed no difference in switching performance between the neutral and serenity groups. As compared with the neutral state, the high-motivating positive affect significantly increased set-switching reaction time costs, but reduced error rate costs; the higher the motivational intensity, the greater the time-costs impairment. This indicates a role of the high-motivating positive affect in regulating the balance between the flexible and stable cognitive control. Motivational intensity also modulated the effects of negative emotional states, i.e., disgust caused a larger increase in time costs than anxiety. Further exploration into neurobiological mechanisms that may mediate the emotional effects on set shifting is warranted.

Negative emotions facilitate isometric force through activation of prefrontal cortex and periaqueductal gray

Emotions are considered to modulate action readiness. Previous studies have demonstrated increased force production following exposure to emotionally arousing visual stimuli; however the neural mechanisms underlying how precise force output is controlled within varying emotional contexts remain poorly understood. To identify the neural correlates of emotion-modulated motor behaviour, twenty-two participants produced a submaximal isometric precision-grip contraction while viewing pleasant, unpleasant, neutral or blank images (without visual feedback of force output). Force magnitude was continuously recorded together with change in brain activity using functional magnetic resonance imaging. Viewing unpleasant images resulted in reduced force decay during force maintenance as compared with pleasant, neutral and blank images. Subjective valence and arousal ratings significantly predicted force production during maintenance. Neuroimaging revealed that negative valence and its interaction with force output correlated with increased activity in right inferior frontal gyrus (rIFG), while arousal was associated with amygdala and periaqueductal gray (PAG) activation. Force maintenance alone was correlated with cerebellar activity. These data demonstrate a valence-driven modulation of force output, mediated by a cortico-subcortical network involving rIFG and PAG. These findings are consistent with engagement of motor pathways associated with aversive motivation, eliciting defensive behaviour and action preparedness in response to negative emotional signals.

The Change of Music Preferences Following the Onset of a Mental Disorder.

A psychiatric population (n=123) was examined on how music preferences had changed after the onset of a mental disorder. Most patients did not change their previous music preference; this group of patients considered music helpful for their mental state, showed more attractivity and enforcement as personality traits and used music more for emotion modulation. Patients who experienced a preference shift reported that music had impaired them during the time of illness; these patients showed less ego-strength, less confidence and less enforcement and used music less for arousal modulation. A third subgroup stopped listening to music completely after the onset of the mental disorder; these patients attribute less importance to music and also reported that music had impaired their mental state. They showed more ego-strength and used music less for emotion modulation. The results suggest that the use of music in everyday life can be helpful as an emotion modulation strategy. However, some patients might need instructions on how to use music in a functional way and not a dysfunctional one. Psychiatrists and psychotherapists as well as music therapists should be aware of emotion modulation strategies, subjective valence of music and personality traits of their patients. Due to the ubiquity of music, psychoeducative instructions on how to use music in everyday life plays an increasing role in the treatment of mental illness.

Self-Reported Trait Mindfulness and Affective Reactivity: A Motivational Approach Using Multiple Psychophysiological Measures

As a form of attention, mindfulness is qualitatively receptive and non-reactive, and is thought to facilitate adaptive emotional responding. One suggested mechanism is that mindfulness facilitates disengagement from an affective stimulus and thereby decreases affective reactivity. However, mindfulness has been conceptualized as a state, intervention, and trait. Because evidence is mixed as to whether self-reported trait mindfulness decreases affective reactivity, we used a multi-method approach to study the relationship between individual differences in self-reported trait mindfulness and electrocortical, electrodermal, electromyographic, and self-reported responses to emotional pictures. Specifically, while participants (N = 51) passively viewed pleasant, neutral, and unpleasant IAPS pictures, we recorded high-density (128 channels) electrocortical, electrodermal, and electromyographic data to the pictures as well as to acoustic startle probes presented during the pictures. Afterwards, participants rated their subjective valence and arousal while viewing the pictures again. If trait mindfulness spontaneously reduces general emotional reactivity, then for individuals reporting high rather than low mindfulness, response differences between emotional and neutral pictures would show relatively decreased early posterior negativity (EPN) and late positive potential (LPP) amplitudes, decreased skin conductance responses, and decreased subjective ratings for valence and arousal. High mindfulness would also be associated with decreased emotional modulation of startle eyeblink and P3 amplitudes. Although results showed clear effects of emotion on the dependent measures, in general, mindfulness did not moderate these effects. For most measures, effect sizes were small with rather narrow confidence intervals. These data do not support the hypothesis that individual differences in self-reported trait mindfulness are related to spontaneous emotional responses during picture viewing.

The change of music preferences following the onset of a mental disorder

A psychiatric population (n=123) was examined on how music preferences had changed after the onset of a mental disorder. Most patients did not change their previous music preference; this group of patients considered music helpful for their mental state, showed more attractivity and enforcement as personality traits and used music more for emotion modulation. Patients who experienced a preference shift reported that music had impaired them during the time of illness; these patients showed less ego-strength, less confidence and less enforcement and used music less for arousal modulation. A third subgroup stopped listening to music completely after the onset of the mental disorder; these patients attribute less importance to music and also reported that music had impaired their mental state. They showed more ego-strength and used music less for emotion modulation. The results suggest that the use of music in everyday life can be helpful as an emotion modulation strategy. However, some patients might need instructions on how to use music in a functional way and not a dysfunctional one. Psychiatrists and psychotherapists as well as music therapists should be aware of emotion modulation strategies, subjective valence of music and personality traits of their patients. Due to the ubiquity of music, psychoeducative instructions on how to use music in everyday life plays an increasing role in the treatment of mental illness.

The brain's response to pleasant touch: an EEG investigation of tactile caressing.

Somatosensation as a proximal sense can have a strong impact on our attitude toward physical objects and other human beings. However, relatively little is known about how hedonic valence of touch is processed at the cortical level. Here we investigated the electrophysiological correlates of affective tactile sensation during caressing of the right forearm with pleasant and unpleasant textile fabrics. We show dissociation between more physically driven differential brain responses to the different fabrics in early somatosensory cortex – the well-known mu-suppression (10–20 Hz) – and a beta-band response (25–30 Hz) in presumably higher-order somatosensory areas in the right hemisphere that correlated well with the subjective valence of tactile caressing. Importantly, when using single trial classification techniques, beta-power significantly distinguished between pleasant and unpleasant stimulation on a single trial basis with high accuracy. Our results therefore suggest a dissociation of the sensory and affective aspects of touch in the somatosensory system and may provide features that may be used for single trial decoding of affective mental states from simple electroencephalographic measurements.

Affect modulated startle in schizophrenia: Subjective experience matters

Data suggests that emotion reactivity as measured by the affect-modulated startle paradigm in those with schizophrenia (SZ) may be similar to healthy controls (HC). However, normative classification of the stimuli may not accurately reflect emotional experience, especially for those with SZ. To examine this possibility, the present study measured the affect-modulated startle response with images classified according to both normative and subjective ratings. Seventeen HC and 17 SZ completed an image viewing task during which startle probes were presented, followed by subjective valence and arousal ratings. Both groups exhibited inhibited startle responses to positive images, intermediate startle amplitudes to neutral images, and potentiated startle amplitudes to negative images. SZ rated the positive images as less positive than HC. When images were reclassified based on subjective valence ratings, both groups’ startle magnitudes increased in response to subjectively rated positive images and decreased to subjectively rated neutral images. The number of trials classified into each valence condition suggested a tendency for SZ to classify neutral images as negative more often than HC. Overall, these findings suggest that affective stimuli modulate the startle response in HC and SZ in similar ways, but subjective emotional experience may differ in those with schizophrenia.

Threatening shapes: The impact of simple geometric configurations on peripheral physiological markers

The fast and reliable neuronal and behavioral responses to negative affective stimuli have been suggested to be at least partly based on the processing of simple geometric configurations within complex visual stimuli. In this context, one line of experimental and neuroimaging evidence suggests that simple V-shaped stimuli result in patterns of neuronal activation and behavioral responses akin to pictures of negative facial expressions. The present study investigated the effects of circles as well as upward and downward pointing triangles in healthy young adults on three peripheral physiological markers – skin conductance response (SCR), facial EMG, and startle reflex – in order to further narrow the gap between neuroimaging findings and behavioral data regarding the impact of geometric shapes. We found significant effects of geometric forms on the startle reflex (p≤0.001, η2=0.080) and the SCR (p=0.029, η2=0.078), but not on facial EMG. Furthermore, subjective valence and arousal ratings of geometric stimuli differed significantly, with downward pointing triangles being perceived as less pleasant and more arousing. In sum, our findings provide further evidence that simple geometric shapes convey emotional meaning. Particularly, the observed changes in SCR and startle response underscore the notion that geometric shapes lead to preparatory changes in physiological activation patterns, which are essential for facilitation of appropriate behavioral responses. However, the smaller effect sizes compared to more realistic affective pictures also highlight the organisms' ability to differentiate between real impending danger and abstract cues in order to avoid unnecessary excessive responses.

Visual emotional information processing in male schizophrenia patients: Combining ERP, clinical and behavioral evidence

We used event-related potentials (ERPs) to examine the time course of visual emotion processing in schizophrenia. ERPs were recorded in 19 chronic male schizophrenia patients and 16 healthy controls (HC) while they viewed IAPS pictures used to induce positive, negative, or neutral mood, presented in a blocked design across three separate occasions. Electrophysiologically, groups differences were found in early potentials (the first 200ms of picture viewing): C1, P1, and N1; also, less positive, broadly distributed P2 was found in the patient group. P2 amplitude to negative valenced pictures only was correlated with self-reported negative mood in the patients. The groups did not differ in late-occurring potentials, specifically the late positive potential (500–1000ms latency window). Patients reported more negative affect before and after the three types of mood induction; however, mood induction influenced both groups in the same direction. Both groups showed similar subjective valence and arousal ratings of evocative stimuli. The ERP results suggest that visual evocative stimuli are differentially processed within the first 200ms, and that the early stages of visual evocative stimuli processing are abnormal in schizophrenia, irrespective of stimulus valence. The correlation found between sensory abnormalities in negative pictures processing and negative mood suggests a relationship between abnormal sensory processes and increased negative mood experience in patients.

Qual é coisa, qual é ela? Avaliação de valência e familiaridade de imagens de objectos desconhecidos

In this paper we present subjective valence and familiarity norms of a set of 100 images of nonfamiliar objects 1 evaluated by a sample of 78 college students. Specifically, each image was evaluated in both dimensions using 9-point scales anchored in Negative/Positive and Not at all Familiar/Very Familiar, by a sub-sample of 39 participants. Such evaluations are presented here (i.e., means, standard-deviations, confidence intervals at the 95% level and correlation between both dimensions) in order to contribute to the enrichment of norms of non-familiar pictorial stimuli. In general, the pretested set of images was evaluated as unfamiliar and of negatively valence.

Gamma flicker elicits positive affect without awareness

High-frequency oscillations emerged as a neural code for both positive affect and fluent attentional processing from evolutionary simulations with artificial neural networks. Visual 50 Hz flicker, which entrains neural oscillations in the gamma band, has been shown to foster attentional switching, but can it also elicit positive affect? A three-faces display (2-female/1-male or 2-male/1-female) was preceded by a 50, 25, or 0 Hz flicker on the position of the odd-one-out (i.e., the target). Participants decided on the gender (Block 1) or on the subjective valence (Block 2) of this neutral target in an approach-avoidance task, which served as an implicit affective measure. Only the detection of 25 Hz flicker, but not of 50 Hz flicker, was above chance (Block 3). Faces primed by invisible 50 Hz flicker were explicitly evaluated more positively than with 25 Hz or 0 Hz. This gamma flicker also facilitated approach reactions, and inhibited avoidance reactions relative to 25 Hz and 0 Hz flicker in Blocks 1 and 2. Attentional switching was, moreover, enhanced by the 50 Hz flicker. According to the Affect-Gamma hypothesis, also in biological neural networks, high-frequency gamma oscillations may code for positive affect.

Emotional Bias in Childhood-Event Interpretation by Adults with Generalized Anxiety Disorder

Objectives: It is often stressed that anxiety alters perceptions of the world by way of processes like the rapid detection of threats and the exaggeration of risks. Given that these processes are active during all information processing, they are thought to influence not only the interpretation of current events, but also the recall of past events. In patient’s anamnesis, we have often attempted to incorporate the events that patients recollect into our functional explanation of their disorder, forgetting that the meaning of what a patient relates may be intrinsically linked to his/her pathology and pathological functioning. We are interested here in potential biases in the events remembered by anxious patients. Methods: We contacted twenty-seven men aged 25 or older suffering from generalized anxiety disorder. They were asked to recollect childhood events from cue words and then rate each remembered event on its subjective emotional valence and intensity, its frequency of recollection, and the vividness of the memory. The responses of the anxious subjects were compared to those of control subjects without psychiatric disorders. Results: Findings seem to show that anxious patients’ memories of childhood events may be impaired by emotional interpretation biases. Indeed, anxious patients remember more negative events than participants in the control group. The emotional intensity of negative or positive events remembered by anxious patients is also considered more important.