Evaluative-feedback stimuli selectively activate the self-related brain area: An fMRI study

Evaluative-feedback, occurring in our daily life, generally contains subjective appraisal of one's specific abilities and personality characteristics besides objective right-or-wrong information. Traditional psychological researches have proved it to be important in building up one's self-concept; however, the neural basis underlying its cognitive processing remains unclear. The present neuroimaging study revealed the mechanism of evaluative-feedback processing at the neural level. 19 healthy Chinese subjects participated in this experiment, and completed the time-estimation task to better their performance according to four types of feedback, namely positive evaluative- and performance-feedback as well as negative evaluative- and performance-feedback. Neuroimaging findings showed that evaluative- rather than performance-feedback can induce increased activities mainly distributed in the cortical midline structures (CMS), including medial prefrontal cortex (BA 8/9)/anterior cigulate cortex (ACC, BA 20), precuneus (BA 7/31) adjacent to posterior cingulate gyrus (PCC, BA 23) of both hemispheres, as well as right inferior lobule (BA 40). This phenomenon can provide evidence that evaluative-feedback may significantly elicit the self-related processing in our brain. In addition, our results also revealed that more brain areas, particularly some self-related neural substrates were activated by the positive evaluative-feedback, in comparative with the negative one. In sum, this study suggested that evaluative-feedback was closely correlated with the self-concept processing, which distinguished it from the performance-feedback.     

Up-regulation of emotional responses to reward-predicting stimuli: An ERP study

Altered reward processing is a hallmark symptom of many psychiatric disorders. It has recently been shown that people are capable of down-regulating reward processing. Here, we examined whether people are capable of up-regulating emotional responses to reward-predicting stimuli. Participants passively viewed colored squares that predicted a reward or no reward, and up- or down-regulated their emotional responses to these reward-predicting stimuli by focusing on the reward meaning or the color of the squares respectively. The amplitude of the late positive potential (LPP) was taken as an objective index of regulation success. The LPP in response to reward-predicting squares was enhanced by up-regulation, suggesting that up-regulation of emotional responses to reward-predicting stimuli using a cognitive strategy is feasible. These results are highly relevant for the treatment of disorders characterized by diminished motivation, and for reward-based decision making in daily life.     

Working memory of somatosensory stimuli: An fMRI study

In a previous study, we have shown that passive recognition of tactile geometrical shapes (i.e. no exploratory movement) engages prefrontal and premotor areas in addition to somatosensory regions (Savini et al., 2010). In the present study we tested the hypothesis that these regions are involved not only in the perception but also during working memory of such somatic information.We performed functional magnetic resonance imaging (fMRI) during the execution of N-BACK tasks, with 2D geometrical shapes blindly pressed on the subjects' right hand palm. Three conditions with increasing memory load (0-BACK, 1-BACK, 2-BACK) were used. Results showed that primary somatosensory area (SI), secondary somatosensory area (SII) and bilateral Insula were active in all conditions, confirming their importance in coding somatosensory stimuli. Activation of fronto-parietal circuit in supplementary motor area (SMA), right superior parietal lobe (rSPL), bilateral middle frontal gyrus, left inferior frontal gyrus, and right superior frontal sulcus was significantly larger during 1-BACK and 2-BACK than 0-BACK. Left superior parietal lobe and right frontal eye field showed a higher activation during the 2-BACK than 0-BACK. Finally, SMA and rSPL were characterized by a statistically significant higher activation during 2-BACK than 1-BACK, revealing their sensitivity to the memory load. These results suggest that working memory of tactile geometrical shapes (no exploratory movement) involves a complex circuit of modal and supramodal fronto-parietal areas.     

Common and specific brain responses to scenic emotional stimuli

Processing of emotions has been an enduring topic of interest in neuroimaging research, but studies have mostly used facial emotional stimuli. The aim of this study was to determine neural networks involved in emotion processing using scenic emotional visual stimuli. One hundred and twenty photographs from the International Affective Picture System (IAPS), including ecological scenes of disgust, fear, happiness, and sadness, were presented to 40 healthy participants while they underwent functional magnetic imaging resonance (fMRI). Afterwards they evaluated the emotional content of the pictures in an offline task. The occipito-temporal cortex and the amygdala–hippocampal complex showed a non-specific emotion-related activation, which was more marked in response to negative emotions than to happiness. The temporo-parietal cortex and the ventral anterior cingulate gyrus showed deactivation, with the former being marked for all emotions except fear and the latter being most marked for disgust. The fusiform gyrus showed activation in response to disgust and deactivation in response to happiness or sadness. Brain regions involved in processing of scenic emotion therefore resemble those reported for facial expressions of emotion in that they respond to a range of different emotions, although there appears to be specificity in the intensity and direction of the response.     

Sleep deprivation alters pupillary reactivity to emotional stimuli in healthy young adults

The aim of this pilot study was to quantify the impact of sleep deprivation on psychophysiological reactivity to emotional stimuli. Following an adaptation night of sleep in the lab, healthy young adults were randomly assigned to either one night of total sleep deprivation or to a normal sleep control condition. The next afternoon, responses to positive, negative, and neutral picture stimuli were examined with pupillography, an indicator of cognitive and affective information processing. Only the sleep-deprived group displayed significantly larger pupil diameter while viewing negative pictures compared to positive or neutral pictures. The sleep-deprived group also showed anticipatory pupillary reactivity during blocks of negative pictures. These data suggest that sleep deprivation is associated with increased reactions to negative emotional information. Such responses may have important implications for psychiatric disorders, which may be triggered or characterized by sleep disturbances.     

Preliminary data on oxytocin modulation of neural reactivity in women to emotional stimuli of children depending on childhood emotional neglect

Sensitivity for rewarding cues and distress signals from children is fundamental to human caregiving and modulated by the neuropeptide oxytocin. In a functional magnetic resonance imaging study, we investigated whether oxytocin regulates neural responses to reward or distress cues form children. In a placebo-controlled, within-subject design, we measured neural responses to positive, negative, and neutral cues from children in 22 healthy female subjects who received oxytocin (24 IU) versus placebo. Further, based on current literature, we hypothesized that oxytocin effects are modulated by experiences of childhood trauma. The task elicited valence-specific effects—positive images activated the ventromedial prefrontal cortex, left anterior cingulate cortex, and right putamen, and images of children in distress activated the bilateral amygdala, hippocampus, and right medial superior frontal cortex. The effects of oxytocin depended on subjective reports of childhood emotional neglect. Self-reported neglect interacted with oxytocin administration in the amygdala, hippocampus, and prefrontal areas. In individuals with higher scores of emotional neglect, oxytocin increased neural reactivity of limbic structures to positive and neutral images. Our findings need replication in larger samples and can therefore be considered preliminary but are in line with the recent literature on the modulating effect of childhood adversity on the sensitivity to oxytocin administration.     

Patient-centered interviewing is associated with decreased responses to painful stimuli: An initial fMRI study

Objective

To identify the functional magnetic resonance imaging (fMRI) changes associated with a patient-centered interview (PCI) and a positive provider–patient relationship (PPR).

Methods

Nine female patients participated, five randomly selected to undergo a replicable, evidence-based PCI, the other four receiving standard clinician-centered interviews (CCI). To verify that PCI differed from CCI, we rated the interviews and administered a patient satisfaction with the provider–patient relationship (PPR) questionnaire. Patients were then scanned as they received painful stimulation while viewing pictures of the interviewing doctor and control images (unknown doctor).

Results

Interview ratings and questionnaire results confirmed that PCIs and CCIs were performed as planned and PCIs led to a much more positive PPR. We found significantly reduced pain-related neural activation in the left anterior insula region in the PCI group when the interviewing doctor's picture was shown.

Conclusion

This study identifies an association between a PCI that produced a positive PPR and reduced pain-related neural responses in the anterior insula. This is an initial step in understanding the neural underpinnings of a PCI.

Practice implications

If confirmed, our results indicate one neurobiological underpinning of an effective PCI, providing an additional scientific rationale for its use clinically.     

Neural activities for negative priming with affective stimuli: An fMRI study

Negative priming refers to the slowing down in reaction time to a stimulus that is either the same as, or related to, a distracting stimulus that has been ignored by people in an immediately preceding trial. It can be used as an index to examine the extent to which people are able to disengage attention or even ignore a distracting stimulus. In this fMRI study, with healthy Mandarin-speaking Chinese participants, we replicated the basic negative priming effect with affectively neutral words. Negative priming was associated with increased activities in the anterior cingulate cortex and the insula, a result that supports the inhibition account of negative priming. We observed that the negative priming effect was attenuated by negative affective words, relative to neutral words, suggesting that subjects’ inhibition of negative information was compromised. Such attenuation of negative priming by negative affective words was associated with increased activities in the ventrolateral and medial frontal regions, the hippocampus, and supplementary motor areas. These observations indicate that specific frontal and subcortical regions take part in attention orientation toward negative-affect information.     

BOLD fMRI mapping of brain responses to nociceptive stimuli in rats under ketamine anesthesia

Ketamine is one of the most commonly used anesthetics, but its effects on nociceptive responses are not clearly defined. This study used blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to hemodynamically map responses to formalin stimuli under ketamine anesthesia. All imaging was performed on a 4.7-T fMRI system. During dynamic image acquisition, formalin was injected into the rat hindpaw as a painful stimulant. Correlation coefficients were calculated, and each image was registered and fused with the corresponding rat brain atlas so as to avoid inaccuracies arising from manual definition of the brain area and to achieve atlas-based normalization among subjects. Formalin injections were found to increase BOLD signals in the cingulate cortex, sensory-motor cortices, insular cortex, striatum, nucleus accumbens, medial thalamus, ventrolateral thalamic group, and hippocampus. Moreover, in contrast to previous pain investigations, the frontal subcortical regions were strongly activated in ketamine-anesthetized rats.     

Alterations in attention capture to auditory emotional stimuli in job burnout: An event-related potential study

Job burnout is a significant cause of work absenteeism. Evidence from behavioral studies and patient reports suggests that job burnout is associated with impairments of attention and decreased working capacity, and it has overlapping elements with depression, anxiety and sleep disturbances. Here, we examined the electrophysiological correlates of automatic sound change detection and involuntary attention allocation in job burnout using scalp recordings of event-related potentials (ERP). Volunteers with job burnout symptoms but without severe depression and anxiety disorders and their non-burnout controls were presented with natural speech sound stimuli (standard and nine deviants), as well as three rarely occurring speech sounds with strong emotional prosody. All stimuli elicited mismatch negativity (MMN) responses that were comparable in both groups. The groups differed with respect to the P3a, an ERP component reflecting involuntary shift of attention: job burnout group showed a shorter P3a latency in response to the emotionally negative stimulus, and a longer latency in response to the positive stimulus. Results indicate that in job burnout, automatic speech sound discrimination is intact, but there is an attention capture tendency that is faster for negative, and slower to positive information compared to that of controls.     

Processing of inconsistent emotional information: an fMRI study

Previous studies investigating the anterior cingulate cortex (ACC) have relied on a number of tasks which involved cognitive control and attentional demands. In this fMRI study, we tested the model that ACC functions as an attentional network in the processing of language. We employed a paradigm that requires the processing of concurrent linguistic information predicting that the cognitive costs imposed by competing trials would engender the activation of ACC. Subjects were confronted with sentences where the semantic content conflicted with the prosodic intonation (CONF condition) randomly interspaced with sentences which conveyed coherent discourse components (NOCONF condition). We observed the activation of the rostral ACC and the middle frontal gyrus when the NOCONF condition was subtracted from the CONF condition. Our findings provide evidence for the involvement of the rostral ACC in the processing of complex competing linguistic stimuli, supporting theories that claim its relevance as a part of the cortical attentional circuit. The processing of emotional prosody involved a bilateral network encompassing the superior and medial temporal cortices. This evidence confirms previous research investigating the neuronal network that supports the processing of emotional information.     

Startle effects on saccadic responses to emotional target stimuli

Startle stimuli elicit various physiological and cognitive responses. This study investigated whether acoustic startle stimuli affect saccadic reactions in an emotional pro‐ or antisaccade task. Startle probes were presented either 500 ms before or simultaneous with an imperative stimulus that indicated whether a saccade towards or away from positive, neutral, or negative peripheral target pictures had to be performed. Valence interacted with saccade direction according to an approach‐avoidance pattern of gaze behavior, with delayed prosaccades to negative targets and antisaccades away from positive targets. Acoustic startle stimuli preceding the presentation of peripheral target pictures speeded up the initiation saccades, irrespective of stimulus valence. Results indicate a speeding of cognitive‐motor processing by preceding startle stimuli.     

Histamine sensitivity influences reactivity to allergens

The ability to mount an IgE response to allergens is a prerequisite for the development of positive allergen skin tests, and this is reflected to some extent by the observation that allergen-responsive subjects tend to have higher total serum IgE concentrations. To determine whether histamine sensitivity also contributes to allergen responsiveness, 893 subjects in a rural community were prick tested with 14 allergens and tenfold dilutions of histamine phosphate beginning at 1 mg/ml-1. IgE was measured in a subset of 400 subjects. Three-way contingency table analysis confirmed previous reports of an association between allergen responsiveness and IgE (p less than 0.001) and also demonstrated that allergen responsiveness is associated with sensitivity to histamine (p less than 0.001). This association is independent of IgE so that the additive effect of IgE and histamine sensitivity allows more nearly accurate prediction of allergen responsiveness than either measurement alone.     

Maternal and infantile influences upon exploratory behavior and emotional reactivity in the albino rat

A 2 × 2 × 2 factorial experiment was conducted to investigate the combined effects of maternal infantile handling, maternal pregnancy (offspring pre-natal) stress, and offspring infantile handling on adult open-field behavior and weight of albino rats. The primary results are as follows: (1) both offspring infantile handling and maternal pregnancy stress tend to increase adult exploratory behavior; (2) adult weight was lower for subjects whose mother had undergone stress during pregnancy than for offspring of non-stress females; (3) several 2-way interactions were found to significantly influence open-field exploration; (4) when offspring infantile handling was combined with maternal pregnancy stress, emotional reactivity (i.e., defecation) was found to increase significantly over that following either type of stimulation alone.     

Anhedonia and emotional responses to affect evoking stimuli

The purpose of the present study was to determine whether individuals with unusually high scores on the Scale for Physical Anhedonia (Chapman et al. 1976) would differ from average scorers in their emotional responses to affect-evoking stimuli. Ten male and ten female anhedonics, as well as ten male and ten female control subjects, were each shown brief filmclips that were expected to elicit emotional responses. The subjects' facial expressions were videotaped while they watched the filmclips, and they also completed adjective checklists describing how they felt while watching them. The anhedonics and nonanhedonics did not differ in their self-reports of emotional experience, nor did they differ in their facial expressions of emotion while viewing the filmclips. Compared to men, women reported experiencing more emotion, and their facial expressions also indicated greater responsiveness.     

An fMRI study of brain activation in a visual adaptation task: activation limited to sensory guidance

Previous neuroimaging studies yielded different patterns of brain areas activated during sensorimotor adaptation, when sensory conflicts are introduced, e.g. by manipulating visual information. We propose that possible reasons might be the lack to control for adaptation or the change in motor performance. In consequence, it was not possible to distinguish between adaptation-related and error-related brain activations. We have developed a sensorimotor adaptation task which controls for these errors using two types of visual distortion and thus is suited to disambiguate sensorimotor adaptation from the related activation patterns. Twenty healthy subjects were scanned by fMRI during a tracking task, while adapting to a visual distortion, which depended either on hand position or on hand velocity. In either case, adaptation was interleaved with a control condition, designed such that the time-course of tracking errors approximated that under visual distortion. We found that adaptation-related neural activation was limited to the left supramarginal and angular gyrus under the position-dependent distortion, but extended bilaterally in the supramarginal gyrus, as well as in the left middle and right superior frontal gyrus under the velocity-dependent distortion. Our findings confirm that equating the errors under both conditions will yield an anatomically more restricted activation pattern compared with other studies. The additional recruitment in right parietal and bilateral frontal areas under the velocity-dependent distortion might reflect a higher computational demand, or the involvement of different adaptive mechanisms.

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Cerebral patterns of attentional habituation to emotional visual stimuli

Attentional habituation in response to emotional stimuli, an aspect of the interaction between cognitive and emotional processes that has received scant attention, was investigated. Event-related potentials were recorded using a 60-electrode array from 25 participants who attended to 120 presentations of three different picture types: emotionally negative (S-), positive (S+), and neutral (SO). The affective content of the stimulation was assessed, through questionnaires, by the participants themselves. N1 showed different patterns of habituation as a function of the stimulation: amplitudes indicated that S- was more resistant to habituation than SO and S+. This pattern, which reflects a greater capacity of S- to attract and maintain the participant's attention, is interpreted as a manifestation of the "negativity bias," a phenomenon that reflects an evolution-favored set of mechanisms that facilitate a rapid and intense response to aversive events.     

Dynamical patterns of human postural responses to emotional stimuli

Postural displacements in response to emotional activation have recently been proposed as a direct and objective index of approach-avoidance behavior in humans. Here, we present the results of an experiment designed to assess spontaneous postural responses to discrete affective pictures, briefly presented in random order of valence. Our findings question the interpretation of phasic postural responses to emotional stimuli as approach-avoidance behavior. Further, we identify a robust dynamical pattern, characterized by specific features indicating that attentional processes may play a role in human postural responses to emotional stimuli.     

Frontal brain asymmetry and emotional reactivity: A biological substrate of affective style

Individuals differ dramatically in the quality and intensity of their response to affectively evocative stimuli. On the basis of prior theory and research, we hypothesized that these individual differences are related to variation in activation of the left and right frontal brain regions. We recorded baseline brain electrical activity from subjects on two occasions 3 weeks apart. Immediately following the second recording, subjects were exposed to brief positive and negative emotional film clips. For subjects whose frontal asymmetry was stable across the 3-week period, greater left frontal activation was associated with reports of more intense positive affect in response to the positive films, whereas greater right frontal activation was associated with more intense reports of negative affect in response to the negative film clips. The methodological and theoretical implications of these data are discussed.