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Lying about the Valence of Affective Pictures: An fMRI Study  [PDF]
Tatia M. C. Lee,Tiffany M. Y. Lee,Adrian Raine,Chetwyn C. H. Chan
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0012291
Abstract: The neural correlates of lying about affective information were studied using a functional magnetic resonance imaging (fMRI) methodology. Specifically, 13 healthy right-handed Chinese men were instructed to lie about the valence, positive or negative, of pictures selected from the International Affective Picture System (IAPS) while their brain activity was scanned by a 3T Philip Achieva scanner. The key finding is that the neural activity associated with deception is valence-related. Comparing to telling the truth, deception about the valence of the affectively positive pictures was associated with activity in the inferior frontal, cingulate, inferior parietal, precuneus, and middle temporal regions. Lying about the valence of the affectively negative pictures, on the other hand, was associated with activity in the orbital and medial frontal regions. While a clear valence-related effect on deception was observed, common neural regions were also recruited for the process of deception about the valence of the affective pictures. These regions included the lateral prefrontal and inferior parietal regions. Activity in these regions has been widely reported in fMRI studies on deception using affectively-neutral stimuli. The findings of this study reveal the effect of valence on the neural activity associated with deception. Furthermore, the data also help to illustrate the complexity of the neural mechanisms underlying deception.
Abnormal Neural Processing during Emotional Salience Attribution of Affective Asymmetry in Patients with Schizophrenia  [PDF]
Seon-Koo Lee, Ji Won Chun, Jung Suk Lee, Hae-Jeong Park, Young-Chul Jung, Jeong-Ho Seok, Jae-Jin Kim
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0090792
Abstract: Aberrant emotional salience attribution has been reported to be an important clinical feature in patients with schizophrenia. Real life stimuli that incorporate both positive and negative emotional traits lead to affective asymmetry such as negativity bias and positivity offset. In this study, we investigated the neural correlates of emotional salience attribution in patients with schizophrenia when affective asymmetry was processed. Fifteen patients with schizophrenia and 14 healthy controls were scanned using functional magnetic resonance imaging (fMRI) while performing an emotion judgment task in which two pictures were juxtaposed. The task consisted of responding to affective asymmetry condition (ambivalent and neutral) and affective symmetry conditions (positive and negative), and group comparisons were performed for each condition. Significantly higher activity in the medial prefrontal cortex and inferior frontal gyrus was observed for the ambivalent condition than for the other conditions in controls, but not in patients. Compared with controls, patients showed decreased activities in the dorsolateral prefrontal cortex, dorsal anterior cingulate cortex, insula, and putamen for the ambivalent condition, but no changes were observed for the neutral condition. Multiple prefrontal hypoactivities during salience attribution of negativity bias in schizophrenia may underlie deficits in the integrative processing of emotional information. Regional abnormalities in the salience network may be the basis of defective emotional salience attribution in schizophrenia, which is likely involved in symptom formation and social dysfunction.
Hemispheric Asymmetry for Affective Stimulus Processing in Healthy Subjects–A fMRI Study  [PDF]
Esther Beraha, Jonathan Eggers, Catherine Hindi Attar, Stefan Gutwinski, Florian Schlagenhauf, Meline Stoy, Philipp Sterzer, Thorsten Kienast, Andreas Heinz, Felix Bermpohl
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0046931
Abstract: Background While hemispheric specialization of language processing is well established, lateralization of emotion processing is still under debate. Several conflicting hypotheses have been proposed, including right hemisphere hypothesis, valence asymmetry hypothesis and region-specific lateralization hypothesis. However, experimental evidence for these hypotheses remains inconclusive, partly because direct comparisons between hemispheres are scarce. Methods The present fMRI study systematically investigated functional lateralization during affective stimulus processing in 36 healthy participants. We normalized our functional data on a symmetrical template to avoid confounding effects of anatomical asymmetries. Direct comparison of BOLD responses between hemispheres was accomplished taking two approaches: a hypothesis-driven region of interest analysis focusing on brain areas most frequently reported in earlier neuroimaging studies of emotion; and an exploratory whole volume analysis contrasting non-flipped with flipped functional data using paired t-test. Results The region of interest analysis revealed lateralization towards the left in the medial prefrontal cortex (BA 10) during positive stimulus processing; while negative stimulus processing was lateralized towards the right in the dorsolateral prefrontal cortex (BA 9 & 46) and towards the left in the amygdala and uncus. The whole brain analysis yielded similar results and, in addition, revealed lateralization towards the right in the premotor cortex (BA 6) and the temporo-occipital junction (BA 19 & 37) during positive stimulus processing; while negative stimulus processing showed lateralization towards the right in the temporo-parietal junction (BA 37,39,42) and towards the left in the middle temporal gyrus (BA 21). Conclusion Our data suggests region-specific functional lateralization of emotion processing. Findings show valence asymmetry for prefrontal cortical areas and left-lateralized negative stimulus processing in subcortical areas, in particular, amygdala and uncus.
Neuromagnetic Indication of Dysfunctional Emotion Regulation in Affective Disorders  [PDF]
Christian Pietrek,Tzvetan Popov,Astrid Steffen,Gregory A. Miller,Brigitte Rockstroh
Depression Research and Treatment , 2012, DOI: 10.1155/2012/156529
Abstract: Dysfunctional emotion regulation is often reported in affective disorders, but it is unclear whether this dysfunction concerns initial processing of emotional input or regulation of resulting emotion. The present study addressed these aspects in 27 depressive and 15 borderline personality disorder patients and 28 healthy controls who were instructed to either passively view unpleasant and neutral pictures or downregulate emotional responses by reappraisal, while neuromagnetic brain activity was measured. All three groups showed more early response to unpleasant than to neutral pictures, whereas patients failed to show subsequent activity suppression under instructions to down-regulate. This deficient emotion regulation was evident primarily in those subjects reporting high childhood adversity. Results support intact emotional input processing but impaired emotion regulation in affective disorders and indicate a moderating influence of early life stress. 1. Introduction Impaired emotion regulation is often discussed as characteristic of disorders of affect. It is reported for major depressive disorder (MDD, [1–4]) and has been described as a core feature in borderline personality disorder (BPD, [5–8]). Dysfunctional emotion regulation could result from impaired initial processing of emotional input or from impaired regulation of physiological and behavioral aspects of resulting emotion. A widely cited model [9, 10] distinguishes perceptual input-oriented processes of monitoring, appraisal, or evaluation of an emotional stimulus and response- or output-oriented regulation processes that may include cognitive reappraisal or response suppression. Similarly, a prominent earlier model [11] centrally distinguished stimulus and response aspects of emotional processing. Research on neural mechanisms associated with this distinction has related input-oriented processes to amygdala and anterior cingulated gyrus (ACC, [10, 12]) and output-oriented regulation processes to ventromedial prefrontal cortex (VMPFC; [10, 13–17]). The interplay of these processes seems crucial for efficient regulation [9, 11]. Emotion dysregulation has been inferred from hemodynamic neuroimaging findings of reduced ventromedial frontal activity during reappraisal, affect discrimination, and emotional Stroop tasks in patients with MDD [1–3] and from augmented limbic activity and reduced orbitofrontal activity in patients with BPD [7]. Moreover, a limbic-prefrontal activity pattern under downregulation instructions opposite to the one characteristic of healthy subjects [2, 18] suggests that
fMRI Scanner Noise Interaction with Affective Neural Processes  [PDF]
Stavros Skouras, Marcus Gray, Hugo Critchley, Stefan Koelsch
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080564
Abstract: The purpose of the present study was the investigation of interaction effects between functional MRI scanner noise and affective neural processes. Stimuli comprised of psychoacoustically balanced musical pieces, expressing three different emotions (fear, neutral, joy). Participants (N=34, 19 female) were split into two groups, one subjected to continuous scanning and another subjected to sparse temporal scanning that features decreased scanner noise. Tests for interaction effects between scanning group (sparse/quieter vs continuous/noisier) and emotion (fear, neutral, joy) were performed. Results revealed interactions between the affective expression of stimuli and scanning group localized in bilateral auditory cortex, insula and visual cortex (calcarine sulcus). Post-hoc comparisons revealed that during sparse scanning, but not during continuous scanning, BOLD signals were significantly stronger for joy than for fear, as well as stronger for fear than for neutral in bilateral auditory cortex. During continuous scanning, but not during sparse scanning, BOLD signals were significantly stronger for joy than for neutral in the left auditory cortex and for joy than for fear in the calcarine sulcus. To the authors' knowledge, this is the first study to show a statistical interaction effect between scanner noise and affective processes and extends evidence suggesting scanner noise to be an important factor in functional MRI research that can affect and distort affective brain processes.
Affective Modeling and Recognition of Learning Emotion: Application to E-learning  [cached]
Yanwen Wu,Tingting Wang,Xiaonian Chu
Journal of Software , 2009, DOI: 10.4304/jsw.4.8.859-866
Abstract: Affective computing has been the focus of artificial intelligence for several years. The amalgamation of affective computing and facial expression recognition technique has lead to the possibility of harmonious human-computer interaction in E-learning. But the fact of E-learning is that emotional absences between computer and E-learner are serious. This paper researches into the learning emotions that E-learner may present. We define three basic learning emotions: absorbed, neuter and fatigue and discuss the features of every defined learning emotion. Layered approach for modeling emotions and facial expression recognition technique are adopted to describe and recognize the defined learning emotions. We also make a demonstrability research, as results indicate, characteristic parameters are exactly identified and face expressions of E-learner are accurately recognized. After E-learner’s emotion state is recognized and confirmed, in the future research, it is possible to take corresponding emotion incentive pleasures of E-learners’ given emotion state to decrease the emotional absences in E-learning.
Voluntary Enhancement of Neural Signatures of Affiliative Emotion Using fMRI Neurofeedback  [PDF]
Jorge Moll, Julie H. Weingartner, Patricia Bado, Rodrigo Basilio, Jo?o R. Sato, Bruno R. Melo, Ivanei E. Bramati, Ricardo de Oliveira-Souza, Roland Zahn
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0097343
Abstract: In Ridley Scott’s film “Blade Runner”, empathy-detection devices are employed to measure affiliative emotions. Despite recent neurocomputational advances, it is unknown whether brain signatures of affiliative emotions, such as tenderness/affection, can be decoded and voluntarily modulated. Here, we employed multivariate voxel pattern analysis and real-time fMRI to address this question. We found that participants were able to use visual feedback based on decoded fMRI patterns as a neurofeedback signal to increase brain activation characteristic of tenderness/affection relative to pride, an equally complex control emotion. Such improvement was not observed in a control group performing the same fMRI task without neurofeedback. Furthermore, the neurofeedback-driven enhancement of tenderness/affection-related distributed patterns was associated with local fMRI responses in the septohypothalamic area and frontopolar cortex, regions previously implicated in affiliative emotion. This demonstrates that humans can voluntarily enhance brain signatures of tenderness/affection, unlocking new possibilities for promoting prosocial emotions and countering antisocial behavior.
Prefrontal Control of the Amygdala during Real-Time fMRI Neurofeedback Training of Emotion Regulation  [PDF]
Vadim Zotev, Raquel Phillips, Kymberly D. Young, Wayne C. Drevets, Jerzy Bodurka
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079184
Abstract: We observed in a previous study (PLoS ONE 6:e24522) that the self-regulation of amygdala activity via real-time fMRI neurofeedback (rtfMRI-nf) with positive emotion induction was associated, in healthy participants, with an enhancement in the functional connectivity between the left amygdala (LA) and six regions of the prefrontal cortex. These regions included the left rostral anterior cingulate cortex (rACC), bilateral dorsomedial prefrontal cortex (DMPFC), bilateral superior frontal gyrus (SFG), and right medial frontopolar cortex (MFPC). Together with the LA, these six prefrontal regions thus formed the functional neuroanatomical network engaged during the rtfMRI-nf procedure. Here we perform a structural vector autoregression (SVAR) analysis of the effective connectivity for this network. The SVAR analysis demonstrates that the left rACC plays an important role during the rtfMRI-nf training, modulating the LA and the other network regions. According to the analysis, the rtfMRI-nf training leads to a significant enhancement in the time-lagged effect of the left rACC on the LA, potentially consistent with the ipsilateral distribution of the monosynaptic projections between these regions. The training is also accompanied by significant increases in the instantaneous (contemporaneous) effects of the left rACC on four other regions – the bilateral DMPFC, the right MFPC, and the left SFG. The instantaneous effects of the LA on the bilateral DMPFC are also significantly enhanced. Our results are consistent with a broad literature supporting the role of the rACC in emotion processing and regulation. Our exploratory analysis provides, for the first time, insights into the causal relationships within the network of regions engaged during the rtfMRI-nf procedure targeting the amygdala. It suggests that the rACC may constitute a promising target for rtfMRI-nf training along with the amygdala in patients with affective disorders, particularly posttraumatic stress disorder (PTSD).
The power of emotional valence—from cognitive to affective processes in reading  [PDF]
Ulrike Altmann,Isabel C. Bohrn,Oliver Lubrich,Arthur M. Jacobs
Frontiers in Human Neuroscience , 2012, DOI: 10.3389/fnhum.2012.00192
Abstract: The comprehension of stories requires the reader to imagine the cognitive and affective states of the characters. The content of many stories is unpleasant, as they often deal with conflict, disturbance or crisis. Nevertheless, unpleasant stories can be liked and enjoyed. In this fMRI study, we used a parametric approach to examine (1) the capacity of increasing negative valence of story contents to activate the mentalizing network (cognitive and affective theory of mind, ToM), and (2) the neural substrate of liking negatively valenced narratives. A set of 80 short narratives was compiled, ranging from neutral to negative emotional valence. For each story mean rating values on valence and liking were obtained from a group of 32 participants in a prestudy, and later included as parametric regressors in the fMRI analysis. Another group of 24 participants passively read the narratives in a three Tesla MRI scanner. Results revealed a stronger engagement of affective ToM-related brain areas with increasingly negative story valence. Stories that were unpleasant, but simultaneously liked, engaged the medial prefrontal cortex (mPFC), which might reflect the moral exploration of the story content. Further analysis showed that the more the mPFC becomes engaged during the reading of negatively valenced stories, the more coactivation can be observed in other brain areas related to the neural processing of affective ToM and empathy.
Resting States Are Resting Traits – An fMRI Study of Sex Differences and Menstrual Cycle Effects in Resting State Cognitive Control Networks  [PDF]
Helene Hjelmervik, Markus Hausmann, Berge Osnes, René Westerhausen, Karsten Specht
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0103492
Abstract: To what degree resting state fMRI is stable or susceptible to internal mind states of the individual is currently an issue of debate. To address this issue, the present study focuses on sex differences and investigates whether resting state fMRI is stable in men and women or changes within relative short-term periods (i.e., across the menstrual cycle). Due to the fact that we recently reported menstrual cycle effects on cognitive control based on data collected during the same sessions, the current study is particularly interested in fronto-parietal resting state networks. Resting state fMRI was measured in sixteen women during three different cycle phases (menstrual, follicular, and luteal). Fifteen men underwent three sessions in corresponding time intervals. We used independent component analysis to identify four fronto-parietal networks. The results showed sex differences in two of these networks with women exhibiting higher functional connectivity in general, including the prefrontal cortex. Menstrual cycle effects on resting states were non-existent. It is concluded that sex differences in resting state fMRI might reflect sexual dimorphisms in the brain rather than transitory activating effects of sex hormones on the functional connectivity in the resting brain.
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