Neural Processing of Food and Erotic Cues in Bulimia Nervosa.

OBJECTIVE: Event-related brain potential (ERP) studies have shown that bulimia nervosa (BN) is associated with facilitated processing of disorder-specific stimuli, visible in altered early components during presentation of food cues and bodies varying in size. Less is known about BN and late ERPs, typically less influenced by perceptual features and regarded as more reliable indices of motivational relevance. The purpose of this study was to use the late positive potential (LPP) to investigate the motivational significance of BN-relevant stimuli. METHODS: Highly salient stimuli, such as pictures of personal binge foods and images that are pleasant, neutral, and unpleasant (e.g., human attacks) were presented to 24 women with bulimia and 24 healthy women (19.7 ± 2.1 and 20.5 ± 2.6 years, respectively). Pictures of erotic couples, previously shown to prompt the greatest appetitive reactions in healthy women, were used as pleasant cues. Based on BN aversion to body cues, we hypothesized that the motivational significance of erotic cues could be increased in bulimic women. RESULTS: Consistent with the literature, the LPP was modulated by the salience of the pictures (F(2.8,130.7) = 24.6, p < .001). An additional interaction with diagnostic group (F(2.8,130.7) = 2.8, p = .047) indicated that bulimic women showed a larger LPP than healthy controls during pictures displaying binge foods (p = .037) and erotic couples (p = .031). CONCLUSIONS: The findings provide objective evidence that BN is characterized by dysregulated emotional processing that is not limited to food cues. The implications are discussed within a transdiagnostic perspective on food-related disorders.

Feeling bad posing as a model: an objective manner of study upward own-body comparisons in body-dissatisfied women.

Emotional effects of upward body comparisons are suggested to occur automatically. A startle reflex paradigm was used to objectively examine the emotions elicited by viewing a picture of one's own body adopting a model pose or a neutral pose, in 30 women with high body dissatisfaction (HBD) and 33 women with low body dissatisfaction (LBD). In-task emotional responses in perceived valence, arousal and control were assessed. Additionally, post-task positive/negative and body-related beauty feelings were recorded. The results revealed that HBD women, compared with LBD women, showed (i) less pleasure, higher activation and less control whilst viewing their own bodies and (ii) less pleasure, more negative/ugliness feelings and an increased startle response when viewing themselves posing as models. The data showed that their own bodies provoked an immediate negative emotional state in HBD women. However, greater aversive psychophysiological mechanisms were automatically activated only when these women posed as models, suggesting that they made upward own-body comparisons.

Resting vagal control and resilience as predictors of cardiovascular allostasis in peacekeepers.

The body's adaptive reaction to a stressful event, an allostatic response, involves vigorous physiological engagement with and efficient recovery from stress. Our aim was to investigate the influence of individual predispositions on cardiac responses to and recovery from a standardized psychosocial stress task (Trier Social Stress Task) in peacekeepers. We hypothesized that those individuals with higher trait resilience and those with higher resting vagal control would be more likely to present an allostatic response: a vigorous cardiac response to stress (i.e., reduction in interbeat intervals and heart rate variability (HRV)) coupled with a significant cardiac recovery in the aftermath. Fifty male military personnel with a mean age of 25.4 years (SD ± 5.99) were evaluated after returning from a peacekeeping mission. Electrocardiogram recordings were made throughout the experimental session, which consisted five conditions: basal, speech preparation, speech delivery, arithmetic task, and recovery. Mean interbeat intervals and HRV were calculated for each condition. An Ego-Resilience Scale and resting vagal control assessed individual predispositions. Stress tasks reduced interbeat intervals (tachycardia) and HRV in comparison with basal, with return to basal in the aftermath (p < 0.001, for all comparisons). Resilience and resting vagal control correlated positively with cardiac parameters for both stress reactivity and recovery (r ≥ 0.29; p < 0.05). In conclusion, peacekeepers showing higher trait resilience and those with higher resting vagal control presented a more adaptive allostatic reaction characterized by vigorous cardiac response to stress (i.e., tachycardia and vagal withdrawal) and efficient cardiac recovery after stress cessation.

Familiarity Processing through Faces and Names: Insights from Multivoxel Pattern Analysis.

The way our brain processes personal familiarity is still debatable. We used searchlight multivoxel pattern analysis (MVPA) to identify areas where local fMRI patterns could contribute to familiarity detection for both faces and name categories. Significantly, we identified cortical areas in frontal, temporal, cingulate, and insular areas, where it is possible to accurately cross-classify familiar stimuli from one category using a classifier trained with the stimulus from the other (i.e., abstract familiarity) based on local fMRI patterns. We also discovered several areas in the fusiform gyrus, frontal, and temporal regions-primarily lateralized to the right hemisphere-supporting the classification of familiar faces but failing to do so for names. Also, responses to familiar names (compared to unfamiliar names) consistently showed less activation strength than responses to familiar faces (compared to unfamiliar faces). The results evinced a set of abstract familiarity areas (independent of the stimulus type) and regions specifically related only to face familiarity, contributing to recognizing familiar individuals.

Affiliative stimuli as primers to prosocial predispositions.

Affiliative stimuli are pleasant and highly biologically relevant. Affiliative cues are thought to elicit a prosocial predisposition. Here affiliative and neutral pictures were exposed prior to a reaction time task which consisted in responding to a visual target. Half the participants responded with finger-flexion, a movement frequently involved in prosocial activities. The other half responded with finger extension, a less prosocially compatible movement. Results showed that under the exposure to affiliative pictures, as compared to neutral ones, participants who used finger flexion were faster, while those using finger extension were slower. Performance benefits to the task, when flexing the finger, together with performance costs, when extending it, indicate the relevance of movement compatibility to the context. These findings put forward a possible link between affiliative primers and motor preparation to facilitate a repertoire of movements related to prosocial predispositions including finger flexion.

EEG-heart rate connectivity changes after sensorimotor rhythm neurofeedback training: Ancillary study.

OBJECTIVES: Neurofeedback can induce long-term changes in brain functional connectivity, but its influence on the connectivity between different physiological systems is unknown. The present paper is an ancillary study of a previous paper that confirmed the effect of neurofeedback on brain connectivity associated with chronic pain. We analysed the influence of neurofeedback on the connectivity between the electroencephalograph (EEG) and heart rate (HR). METHODS: Seventeen patients diagnosed with fibromyalgia were divided into three groups: good sensorimotor rhythm (SMR) training responders (n = 4), bad SMR responders (n = 5) and fake training (SHAM, n = 8). Training consisted of six sessions in which participants learned to synchronize and desynchronize SMR power. Before the first training (pre-resting state) and sixth training (post-resting state) session, open-eye resting-state EEG and electrocardiograph signals were recorded. RESULTS: Good responders reduced pain ratings after SMR neurofeedback training. This improvement in fibromyalgia symptoms was associated with a reduction of the connectivity between the central area and HR, between central and frontal areas, within the central area itself, and between central and occipital areas. The sham group and poor responders experienced no changes in their fibromyalgia symptoms. CONCLUSIONS: Our results provide new evidence that neurofeedback is a promising tool that can be used to treat of chronic pain syndromes and to obtain a better understanding of the interactions between physiological networks. These findings are preliminary, but they may pave the way for future studies that are more methodologically robust. In addition, new research questions are raised: what is the role of the central-peripheral network in chronic pain and what is the effect of neurofeedback on this network.

Tonic pain reduces autonomic responses and EEG functional connectivity elicited by affective stimuli.

Most pain studies have focused on only two aspects of pain: the influence of pain on attentional processing and the modulation of pain perception by affective stimuli. However, the influence of tonic pain on the attentional processing of affective stimuli has not been studied. In this study, we investigated the effects of tonic pain on the attentional processing of affective stimuli, focusing on autonomic responses and their relationship with both EEG power and functional connectivity. Forty participants (20 men and 20 women) received tonically painful and nonpainful thermal stimulation while viewing blocks of pleasant, unpleasant, or neutral images. The galvanic skin conductance response (SCR), electrocardiographic activity, and electroencephalographic (EEG) activity in the delta and theta bands were recorded. Participants rated the unpleasantness of the pain at the end of each block. Typical affective SCR and heart rate (HR) patterns were found in the no-pain condition, but when the pain was delivered, these patterns disappeared. EEG power and functional connectivity results showed that tonic pain affected the delta band in the central region during pleasant and unpleasant image blocks. Our findings suggest that tonic pain captured attentional focus and reduced the cognitive resources available for processing affective stimuli, altering the emotional experience associated with pain.

Stroop matching task: role of feature selection and temporal modulation.

We conducted an event-related potential (ERP) study to investigate the electrocortical dynamics of attentional feature-based processing in the Stroop matching task. Participants in the study (n = 37) compared the ink color of a colored word with the meaning of a color-word in white ink. The two task stimuli were presented simultaneously or with SOAs (Stimulus Onset Asynchrony) of 400 and 1,200 ms. The Stroop matching effect was maximal during SOA-0, was reduced at SOA-400, and was inverted at SOA-1200. We focused the ERP analysis on the N1 component. Paralleling the behavioral results, the N1 amplitude was greater for congruent stimuli than incongruent stimuli during SOA-0. This difference was attenuated at SOA-400, and at SOA-1200, an inverse pattern was observed. The results provide evidence that early selection processing participated in the Stroop matching task phenomenon and also suggest that the temporal modulation of early attention is a function of task characteristics such as SOA.

[Neuropsychological aspects of nicotine craving]. / Aspectos neuropsicológicos del craving por la nicotina.

Craving has been defined as the motivation to self-administer a substance previously consumed. It has been hypothesized that craving contributes significantly to compulsive drug use and relapse after a period of abstinence in humans. Neuropsychological and brain-imaging studies have identified numerous brain regions that may be involved in craving. In this paper, the neuropsychological mechanisms of craving for nicotine are reviewed, focusing on three systems that appear to be involved in craving states. First of all, the reward system, responsible for the development of dependence and craving. Secondly, the emotional and associative system, which is related to conditioned craving. And third, the system involved in the neural basis of cognitive and decision making processes. The most influential theoretical models on craving are also reviewed, including those based on conditioning mechanisms, on cognitive mechanisms and on cognitive-behavioral mechanisms, as well as the neurobiological model. Factors related to the evaluation and treatment of craving are also discussed, with particular emphasis on clinical aspects. Finally, we stress the importance of a multidisciplinary approach for achieving a common model on craving and improving the diagnostic tools and treatment strategies.

Social Support and Longevity: Meta-Analysis-Based Evidence and Psychobiological Mechanisms.

Over the past 60 years, evidence has accumulated on the fundamental role of supportive social relationships in individual health and longevity. This paper first summarizes the results of 23 meta-analyses published between 1994 and 2021, which include 1,187 longitudinal and cross-sectional studies with more than 1,458 million participants. The effect sizes reported in these meta-analyses are highly consistent with regard to the predicted link between social support and reduced disease and mortality; the meta-analyses also highlight various theoretical and methodological issues concerning the multi-dimensionality of the social support concept and its measurements, and the need to control potential confounding and moderator variables. This is followed by an analysis of the experimental evidence from laboratory studies on psychobiological mechanisms that may explain the effect of social support on health and longevity. The stress-buffering hypothesis is examined and extended to incorporate recent findings on the inhibitory effect of social support figures (e.g., the face of loved ones) on fear learning and defensive reactions alongside evidence on the effect of social support on brain networks that down-regulate the autonomic nervous system, HPA axis, and immune system. Finally, the paper discusses the findings in the context of three emerging research areas that are helping to advance and consolidate the relevance of social factors for human health and longevity: (a) convergent evidence on the effects of social support and adversity in other social mammals, (b) longitudinal studies on the impact of social support and adversity across each stage of the human lifespan, and (c) studies that extend the social support framework from individual to community and societal levels, drawing implications for large-scale intervention policies to promote the culture of social support.

Two scales to evaluate cocaine craving.

The cocaine craving questionnaire-brief (CCQ-Brief English) asks cocaine users to report their level of craving now. We constructed two brief scales of cocaine craving in a sample of 107 Spanish-speaking natives in treatment for cocaine abuse or dependence: the CCQ-Brief(Spanish) and the pictographic assessment of desire (PAD), which relies less on language. Principal component analyses yielded a one-component solution for the CCQ-Brief, explaining between 62% and 68% of the sample variability. Cronbach's alpha ranged from .92 to .94. The CCQ-Brief and the PAD were strongly correlated; effect sizes ranged from .42 to .68 in separate trials. Laboratory cue-exposure results showed that in both scales craving was higher upon presentation of cocaine-related rather than neutral pictorial stimuli. The CCQ-Brief and PAD are potentially valuable scales for evaluating cocaine craving.

Sympathetic contributions to habituation and recovery of the cardiac defense response.

The cardiac defense response (CDR) to intense auditory stimulation is characterized by two acceleration-deceleration heart rate (HR) components. This study investigated contributions of sympathetic cardiac control to habituation and recovery of the CDR. Fifty-six healthy subjects were presented with noise stimuli eliciting the CDR. Three stimuli were presented with short and long (2.5 min and 12.5 min) inter-trial intervals (ITIs). The pre-ejection period was recorded as an index of sympathetic cardiac control, in addition to HR. Repeated stimulation at short ITI was associated with marked habituation of the HR and sympathetic responses; both responses exhibited a degree of recovery with long ITI. Regarding the time course, the first acceleration-deceleration was accompanied by a decline and subsequent increase in sympathetic cardiac control. During the second acceleration-deceleration, the parameters exhibited parallel courses. These results suggest that the sympathetic contribution to the habituation and recovery is limited to the second HR component.

Positive emotional reactions to loved names.

Studies concerning personal attachment have successfully used loved familiar faces to prompt positive affective and physiological reactions. Moreover, the processing of emotional words shows similar physiological patterns to those found with affective pictures. The objective of this study was to assess whether the passive viewing of loved names would produce a pattern of subjective and physiological reactivity similar to that produced by the passive viewing of loved faces. The results showed that, compared to neutral (unknown) and famous names, loved names produced a biphasic pattern of heart rate deceleration-acceleration, heightened skin conductance and zygomaticus muscle activity, inhibition of corrugator muscle activity, and potentiation of the startle reflex response. This pattern of physiological responses was accompanied by subjective reports of higher positive affect and arousal for loved names than for neutral and famous ones. These findings highlight not only the similarity but also the differences between the affective processing of identity recognition by loved faces and names.

Emotional Impact and Perceived Effectiveness of Text-Only versus Graphic Health Warning Tobacco Labels on Adolescents.

The study of smoking in adolescence is of major importance as nicotine dependence often begins in younger groups. Tobacco health warnings have been introduced to inform people of the negative consequences of smoking. This study assessed the emotions and perceived effectiveness of two formats of tobacco warnings on adolescents: Text-only versus graphic warning labels. In addition, we analyzed how emotions predicted their perceived effectiveness. In a cross-sectional study, 413 adolescents (131 smokers, 282 non-smokers) between 13-20 years of age rated their emotions (valence and arousal) and perceived effectiveness towards a set of tobacco warnings. Results showed that graphic warnings evoked higher arousal than text-only warning labels (p = .038). Most of the warning labels also evoked unpleasantness with smokers reporting higher unpleasantness regarding text-only warnings compared to non-smokers (p = .002). In contrast, perceived effectiveness of the warnings was lower in smokers than in non-smokers (p = .029). Finally, high arousal and being a non-smoker explained 14% of the variance of perceiving the warnings more effective. Given the role that warnings may play in increasing health awareness, these findings highlight how smoking status and emotions are important predictors of the way adolescents consider tobacco health labels to be effective.

The Relationship Between Heart Rate Variability and Electroencephalography Functional Connectivity Variability Is Associated With Cognitive Flexibility.

The neurovisceral integration model proposes a neuronal network that is related to heart rate activity and cognitive performance. The aim of this study was to determine whether heart rate variability (HRV) and variability in electroencephalographic (EEG) functional connectivity in the resting state are related to cognitive flexibility. Thirty-eight right-handed students completed the CAMBIOS test, and their heart and EEG activity was recorded during 6 min in the resting state with their eyes open. We calculated correlations, partial correlations and multiple linear regressions among HRV indices, functional brain connectivity variability and CAMBIOS scores. Furthermore, the sample was divided into groups according to CAMBIOS performance, and one-way ANOVA was applied to evaluate group differences. Our results show direct and inverse correlations among cognitive flexibility, connectivity (positive and negative task networks) and heartbeat variability. Partial correlations and multiple linear regressions suggest that the relation between HRV and CAMBIOS performance is mediated by neuronal oscillations. ANOVA confirms that HRV and variability in functional brain connectivity is related to cognitive performance. In conclusion, the levels of brain signal variability might predict cognitive flexibility in a cognitive task, while HRV might predict cognitive flexibility only when it is mediated by neuronal oscillations.

Heart-rate modulations reveal attention and consciousness interactions.

Our environment is constantly overloaded with information, although we cannot consciously process all the stimulation reaching our senses. Current theoretical models are focused on the cognitive and neural processes underlying conscious perception. However, cognitive processes do not occur in an isolated brain but in a complex interaction between the environment, the brain, and the organism. The brain-body interaction has largely been neglected in the study of conscious perception. The aim of the present study was to explore if heart rate and skin conductance (SC) are modulated by the interaction between phasic alertness and conscious perception. We presented near-threshold visual stimuli that could be preceded by an alerting tone on 50% of the trials. Behaviorally, phasic alerting improved perceptual sensitivity for detecting a near-threshold stimulus (along with changes in response criterion). Following the alerting tone, a cardiac deceleration-acceleration pattern was observed, which was more pronounced when the near-threshold stimulus was consciously perceived in comparison with unconsciously perceived stimuli. SC results further showed some degree of subliminal processing of unseen stimuli. These results reveal that cardiac activity could be a marker of attention and consciousness interactions, emphasizing the need for taking into account brain-body interactions for current theoretical models of consciousness.

The affective processing of loved familiar faces and names: Integrating fMRI and heart rate.

The neuroscientific study of love has been boosted by an extended corpus of research on face-identity recognition. However, few studies have compared the emotional mechanisms activated by loved faces and names and none have simultaneously examined fMRI and autonomic measures. The present study combined fMRI with the heart rate response when 21 participants (10 males) passively viewed the face or the written name of 4 loved people and 4 unknown people. The results showed accelerative patterns in heart rate, together with brain activations, which were significantly higher for loved people than for unknown people. Significant correlations were found between heart rate and brain activation in frontal areas, for faces, and in temporal areas, for names. The results are discussed in the context of previous studies using the same passive viewing procedure, highlighting the relevance of integrating peripheral and central measures in the scientific study of positive emotion and love.

Tonic Immobility in PTSD: Exacerbation of Emotional Cardiac Defense Response.

Among defensive behaviors, tonic immobility (TI) is considered the last defensive resort when life is at extreme risk. Post-Traumatic Stress Disorder (PTSD) is the main psychiatric consequence resulting from exposure to traumatic events. Increasing evidence indicate an association between peritraumatic tonic immobilility and severity of PTSD. Cardiac defense response, a reactivity to perceived danger or threat, has been studied by recording heart rate changes that follows the presentation of an unpredictable intense auditory aversive stimulus. The aim of this study was to investigate potential distinctiveness in cardiac defense response among PTSD patients who presented - compared to those that did not - TI reaction in the laboratory setting. Patients (N = 17) completed the TI questionnaire for signs of immobility elicited by passive listening to their autobiographical trauma script. After a while, they were exposed to an intense white noise, while electrocardiogram was recorded. The heart rate during the 80 s after the noise, subtracted from baseline, was analyzed. Higher reports of TI to the trauma script were associated with stronger and sustained heart rate accelerations after the noise. The effects on cardiac defense response add to increasing evidence that some PTSD patients are prone to repeated re-experiences of TI, which may implicate in a potentially distinct pathophysiology and even a new PTSD subtype.

The effect of startle reflex habituation on cardiac defense: interference between two protective reflexes.

The present study investigated the relationship between blink startle and cardiac defense, two protective reflexes that are said to be elicited by the transient and the sustained components, respectively, of high intensity stimuli. Three groups of participants were presented with three intense long lasting noise stimuli (500ms) after habituation training with 12 brief (50ms) high intensity noise bursts (High group), low intensity noise bursts (Low group) or high intensity visual stimuli (Light group). The transition from habituation to defense stimuli resulted in increased blink startles in groups Low and Light, but not in group High. A cardiac defense reflex, characterised by a short and long delayed increase in heart rate, was observed in group Light, but not in groups Low and High. This pattern of results indicates that habituation to startle eliciting stimuli will impair defense reflexes elicited on subsequent test trials and suggests some interrelation between the two reflex systems.

[The International Affective Digitized Sounds (IADS): Spanish norms]. / El Sistema Internacional de Sonidos Afectivos (IADS):adaptación española.

The International Affective Digitized Sounds (IADS): Spanish Norms. The Spanish norms for the International Affective Digitized Sounds (IADS) are reported. The IADS is a standardized set of 110 digitalized sounds which are both reliable and valid for the experimental study of emotional processes. The construction of the IADS is based on Peter J. Lang's dimensional model of emotions. Participants were 1.716 university students (1.136 women) who assessed the sounds using the three scales of the Self-Assessment Manikin: affective valence, arousal, and dominance. The results show a distribution of the sounds, within the bidimensional plot defined by valence and arousal, similar to the North-American student population with a typical boomerang shape. No significant differences were found when comparing men and women nor when comparing the Spanish and North-American samples in the total set of sounds. The results are discussed in relation to the International Affective Picture System (IAPS). The norms for each of the 110 sounds are presented in an annexed table.