Anders S, Eippert F, Wiens S, Birbaumer N, Lotze M, Wildgruber D.
Brain, in press
Affective neuroscience has been strongly influenced by the view that a 'feeling' is the perception of somatic changes and has consequently often neglected the neural mechanisms that underlie the integration of somatic and other information in affective experience. Here, we investigate affective processing by means of functional magnetic resonance imaging in nine cortically blind patients. In these patients, unilateral postgeniculate lesions prevent primary cortical visual processing in part of the visual field which, as a result, becomes subjectively blind. Residual subcortical processing of visual information, however, is assumed to occur in the entire visual field. As we have reported earlier, these patients show significant startle reflex potentiation when a threat-related visual stimulus is shown in their blind visual field. Critically, this was associated with an increase of brain activity in somatosensory-related areas, and an increase in experienced negative affect. Here, we investigated the patients' response when the visual stimulus was shown in the sighted visual field, that is, when it was visible and cortically processed. Despite the fact that startle reflex potentiation was similar in the blind and sighted visual field, patients reported significantly less negative affect during stimulation of the sighted visual field. In other words, when the visual stimulus was visible and received full cortical processing, the patients' phenomenal experience of affect did not closely reflect somatic changes. This decoupling of phenomenal affective experience and somatic changes was associated with an increase of activity in the left ventrolateral prefrontal cortex and a decrease of affect-related somatosensory activity. Moreover, patients who showed stronger left ventrolateral prefrontal cortex activity tended to show a stronger decrease of affect-related somatosensory activity. Our findings show that similar affective somatic changes can be associated with different phenomenal experiences of affect, depending on the depth of cortical processing. They are in line with a model in which the left ventrolateral prefrontal cortex is a relay station that integrates information about subcortically triggered somatic responses and information resulting from in-depth cortical stimulus processing. Tentatively, we suggest that the observed decoupling of somatic responses and experienced affect, and the reduction of negative phenomenal experience, can be explained by a left ventrolateral prefrontal cortex-mediated inhibition of affect-related somatosensory activity.
Friday, September 25, 2009
ARTICLE UPDATE - The convergence of information about rewarding and aversive stimuli in single neurons.
Morrison SE, Salzman CD.
The Journal of Neuroscience, 29, 11471-11483
Neuroscientists, psychologists, clinicians, and economists have long been interested in how individuals weigh information about potential rewarding and aversive stimuli to make decisions and to regulate their emotions. However, we know relatively little about how appetitive and aversive systems interact in the brain, as most prior studies have investigated only one valence of reinforcement. Previous work has suggested that primate orbitofrontal cortex (OFC) represents information about the reward value of stimuli. We therefore investigated whether OFC also represents information about aversive stimuli, and, if so, whether individual neurons process information about both rewarding and aversive stimuli. Monkeys performed a trace conditioning task in which different novel abstract visual stimuli (conditioned stimuli, CSs) predicted the occurrence of one of three unconditioned stimuli (USs): a large liquid reward, a small liquid reward, or an aversive air-puff. Three lines of evidence suggest that information about rewarding and aversive stimuli converges in individual neurons in OFC. First, OFC neurons often responded to both rewarding and aversive USs, despite their different sensory features. Second, OFC neural responses to CSs often encoded information about both potential rewarding and aversive stimuli, even though these stimuli differed in both valence and sensory modality. Finally, OFC neural responses were correlated with monkeys' behavioral use of information about both rewarding and aversive CS-US associations. These data indicate that processing of appetitive and aversive stimuli converges at the single cell level in OFC, providing a possible substrate for executive and emotional processes that require using information from both appetitive and aversive systems.
The Journal of Neuroscience, 29, 11471-11483
Neuroscientists, psychologists, clinicians, and economists have long been interested in how individuals weigh information about potential rewarding and aversive stimuli to make decisions and to regulate their emotions. However, we know relatively little about how appetitive and aversive systems interact in the brain, as most prior studies have investigated only one valence of reinforcement. Previous work has suggested that primate orbitofrontal cortex (OFC) represents information about the reward value of stimuli. We therefore investigated whether OFC also represents information about aversive stimuli, and, if so, whether individual neurons process information about both rewarding and aversive stimuli. Monkeys performed a trace conditioning task in which different novel abstract visual stimuli (conditioned stimuli, CSs) predicted the occurrence of one of three unconditioned stimuli (USs): a large liquid reward, a small liquid reward, or an aversive air-puff. Three lines of evidence suggest that information about rewarding and aversive stimuli converges in individual neurons in OFC. First, OFC neurons often responded to both rewarding and aversive USs, despite their different sensory features. Second, OFC neural responses to CSs often encoded information about both potential rewarding and aversive stimuli, even though these stimuli differed in both valence and sensory modality. Finally, OFC neural responses were correlated with monkeys' behavioral use of information about both rewarding and aversive CS-US associations. These data indicate that processing of appetitive and aversive stimuli converges at the single cell level in OFC, providing a possible substrate for executive and emotional processes that require using information from both appetitive and aversive systems.
ARTICLE UPDATE - Propensity and sensitivity measures of fear and disgust are differentially related to emotion-specific brain activation.
Schäfer A, Leutgeb V, Reishofer G, Ebner F, Schienle A.
Neuroscience Letters, in press
Neuroimaging studies on individual differences in experiencing disgust and fear have indicated that disgust propensity and trait anxiety are able to moderate brain activity. The moderating role of disgust sensitivity and anxiety sensitivity has not been investigated thus far. Both sensitivity traits refer to the tendency of a person to perceive harmful consequences of experiencing fear and disgust. Eighteen female subjects viewed and subsequently rated pictures for the elicitation of disgust, fear and a neutral affective state. The viewing of the aversive pictures was associated with activation of visual processing areas, the amygdala, the insula and the orbitofrontal cortex (OFC). In the disgust condition, disgust propensity was positively correlated with activation of attention-related areas (parietal cortex, anterior cingulate cortex (ACC)) and brain regions involved in valence and arousal processing (OFC, insula). For the fear condition, we observed positive correlations between trait anxiety and activation of the ACC, the insula, and the OFC. Correlations between brain activity and sensitivity measures were exclusively negative and concerned areas crucial for emotion regulation, such as the medial and dorsolateral prefrontal cortex (MPFC, DLPFC). Thus, individuals high in disgust/anxiety sensitivity might have difficulties to successfully control the specific affective experience.
Neuroscience Letters, in press
Neuroimaging studies on individual differences in experiencing disgust and fear have indicated that disgust propensity and trait anxiety are able to moderate brain activity. The moderating role of disgust sensitivity and anxiety sensitivity has not been investigated thus far. Both sensitivity traits refer to the tendency of a person to perceive harmful consequences of experiencing fear and disgust. Eighteen female subjects viewed and subsequently rated pictures for the elicitation of disgust, fear and a neutral affective state. The viewing of the aversive pictures was associated with activation of visual processing areas, the amygdala, the insula and the orbitofrontal cortex (OFC). In the disgust condition, disgust propensity was positively correlated with activation of attention-related areas (parietal cortex, anterior cingulate cortex (ACC)) and brain regions involved in valence and arousal processing (OFC, insula). For the fear condition, we observed positive correlations between trait anxiety and activation of the ACC, the insula, and the OFC. Correlations between brain activity and sensitivity measures were exclusively negative and concerned areas crucial for emotion regulation, such as the medial and dorsolateral prefrontal cortex (MPFC, DLPFC). Thus, individuals high in disgust/anxiety sensitivity might have difficulties to successfully control the specific affective experience.
ARTICLE UPDATE - Brain networks involved in haptic and visual identification of facial expressions of emotion: An fMRI study
Kitada R, Johnsrude IS, Kochiyama T, Lederman SJ.
Neuroimage, in press
Previous neurophysiological and neuroimaging studies have shown that a cortical network involving the inferior frontal gyrus (IFG), inferior parietal lobe (IPL) and cortical areas in and around the posterior superior temporal sulcus (pSTS) region are employed in action understanding by vision and audition. However, the brain regions that are involved in action understanding by touch are unknown. Lederman et al. (2007) recently demonstrated that humans can haptically recognize facial expressions of emotion (FEE) surprisingly well. Here, we report a functional magnetic resonance imaging (fMRI) study in which we test the hypothesis that the IFG, IPL and pSTS regions are involved in haptic, as well as visual, FEE identification. Twenty subjects haptically or visually identified facemasks with three different FEEs (disgust, neutral and happiness) and casts of shoes (shoes) of three different types. The left posterior middle temporal gyrus, IPL, IFG, and bilateral precentral gyrus were activated by FEE identification relative to that of shoes, regardless of sensory modality. By contrast, an inferomedial part of the left superior parietal lobule was activated by haptic, but not visual, FEE identification. Other brain regions, including the lingual gyrus and superior frontal gyrus, were activated by visual identification of FEEs, relative to haptic identification of FEEs. These results suggest that haptic and visual FEE identification rely on distinct but overlapping neural substrates including the IFG, IPL and pSTS region.
Neuroimage, in press
Previous neurophysiological and neuroimaging studies have shown that a cortical network involving the inferior frontal gyrus (IFG), inferior parietal lobe (IPL) and cortical areas in and around the posterior superior temporal sulcus (pSTS) region are employed in action understanding by vision and audition. However, the brain regions that are involved in action understanding by touch are unknown. Lederman et al. (2007) recently demonstrated that humans can haptically recognize facial expressions of emotion (FEE) surprisingly well. Here, we report a functional magnetic resonance imaging (fMRI) study in which we test the hypothesis that the IFG, IPL and pSTS regions are involved in haptic, as well as visual, FEE identification. Twenty subjects haptically or visually identified facemasks with three different FEEs (disgust, neutral and happiness) and casts of shoes (shoes) of three different types. The left posterior middle temporal gyrus, IPL, IFG, and bilateral precentral gyrus were activated by FEE identification relative to that of shoes, regardless of sensory modality. By contrast, an inferomedial part of the left superior parietal lobule was activated by haptic, but not visual, FEE identification. Other brain regions, including the lingual gyrus and superior frontal gyrus, were activated by visual identification of FEEs, relative to haptic identification of FEEs. These results suggest that haptic and visual FEE identification rely on distinct but overlapping neural substrates including the IFG, IPL and pSTS region.
Friday, September 11, 2009
ARTICLE UPDATE - Emotional Conception: How Embodied Emotion Concepts Guide Perception and Facial Action.
Halberstadt J, Winkielman P, Niedenthal PM, Dalle N.
Psychological Science, in press
This study assessed embodied simulation via electromyography (EMG) as participants first encoded emotionally ambiguous faces with emotion concepts (i.e., "angry,""happy") and later passively viewed the faces without the concepts. Memory for the faces was also measured. At initial encoding, participants displayed more smiling-related EMG activity in response to faces paired with "happy" than in response to faces paired with "angry." Later, in the absence of concepts, participants remembered happiness-encoded faces as happier than anger-encoded faces. Further, during passive reexposure to the ambiguous faces, participants' EMG indicated spontaneous emotion-specific mimicry, which in turn predicted memory bias. No specific EMG activity was observed when participants encoded or viewed faces with non-emotion-related valenced concepts, or when participants encoded or viewed Chinese ideographs. From an embodiment perspective, emotion simulation is a measure of what is currently perceived. Thus, these findings provide evidence of genuine concept-driven changes in emotion perception. More generally, the findings highlight embodiment's role in the representation and processing of emotional information.
Psychological Science, in press
This study assessed embodied simulation via electromyography (EMG) as participants first encoded emotionally ambiguous faces with emotion concepts (i.e., "angry,""happy") and later passively viewed the faces without the concepts. Memory for the faces was also measured. At initial encoding, participants displayed more smiling-related EMG activity in response to faces paired with "happy" than in response to faces paired with "angry." Later, in the absence of concepts, participants remembered happiness-encoded faces as happier than anger-encoded faces. Further, during passive reexposure to the ambiguous faces, participants' EMG indicated spontaneous emotion-specific mimicry, which in turn predicted memory bias. No specific EMG activity was observed when participants encoded or viewed faces with non-emotion-related valenced concepts, or when participants encoded or viewed Chinese ideographs. From an embodiment perspective, emotion simulation is a measure of what is currently perceived. Thus, these findings provide evidence of genuine concept-driven changes in emotion perception. More generally, the findings highlight embodiment's role in the representation and processing of emotional information.
ARTICLE UPDATE - Interactions of attention, emotion and motivation.
Raymond J.
Progress in Brain Research, 176, 293-308
Although successful visually guided action begins with sensory processes and ends with motor control, the intervening processes related to the appropriate selection of information for processing are especially critical because of the brain's limited capacity to handle information. Three important mechanisms--attention, emotion and motivation--contribute to the prioritization and selection of information. In this chapter, the interplay between these systems is discussed with emphasis placed on interactions between attention (or immediate task relevance of stimuli) and emotion (or affective evaluation of stimuli), and between attention and motivation (or the predicted value of stimuli). Although numerous studies have shown that emotional stimuli modulate mechanisms of selective attention in humans, little work has been directed at exploring whether such interactions can be reciprocal, that is, whether attention can influence emotional response. Recent work on this question (showing that distracting information is typically devalued upon later encounters) is reviewed in the first half of the chapter. In the second half, some recent experiments exploring how prior value-prediction learning (i.e., learning to associate potential outcomes, good or bad, with specific stimuli) plays a role in visual selection and conscious perception. The results indicate that some aspects of motivation act on selection independently of traditionally defined attention and other aspects interact with it.
Progress in Brain Research, 176, 293-308
Although successful visually guided action begins with sensory processes and ends with motor control, the intervening processes related to the appropriate selection of information for processing are especially critical because of the brain's limited capacity to handle information. Three important mechanisms--attention, emotion and motivation--contribute to the prioritization and selection of information. In this chapter, the interplay between these systems is discussed with emphasis placed on interactions between attention (or immediate task relevance of stimuli) and emotion (or affective evaluation of stimuli), and between attention and motivation (or the predicted value of stimuli). Although numerous studies have shown that emotional stimuli modulate mechanisms of selective attention in humans, little work has been directed at exploring whether such interactions can be reciprocal, that is, whether attention can influence emotional response. Recent work on this question (showing that distracting information is typically devalued upon later encounters) is reviewed in the first half of the chapter. In the second half, some recent experiments exploring how prior value-prediction learning (i.e., learning to associate potential outcomes, good or bad, with specific stimuli) plays a role in visual selection and conscious perception. The results indicate that some aspects of motivation act on selection independently of traditionally defined attention and other aspects interact with it.
ARTICLE UPDATE - Emotional modulation of visual cortex activity: a functional near-infrared spectroscopy study.
Emotional modulation of visual cortex activity: a functional near-infrared spectroscopy study.
Neuroreport, in press
Functional neuroimaging and electroencephalography reveal emotional effects in the early visual cortex. Here, we used functional near-infrared spectroscopy to examine haemodynamic responses evoked by neutral, positive and negative emotional pictures, matched for brightness, contrast, hue, saturation, spatial frequency and entropy. Emotion content modulated amplitude and latency of oxy, deoxy and total haemoglobin response peaks, and induced peripheral autonomic reactions. The processing of positive and negative pictures enhanced haemodynamic response amplitude, and this effect was paralleled by blood pressure changes. The processing of positive pictures was reflected in reduced haemodynamic response peak latency. Together these data suggest that the early visual cortex holds amplitude-dependent representation of stimulus salience and latency-dependent information regarding stimulus valence, providing new insight into affective interaction with sensory processing.
Neuroreport, in press
Functional neuroimaging and electroencephalography reveal emotional effects in the early visual cortex. Here, we used functional near-infrared spectroscopy to examine haemodynamic responses evoked by neutral, positive and negative emotional pictures, matched for brightness, contrast, hue, saturation, spatial frequency and entropy. Emotion content modulated amplitude and latency of oxy, deoxy and total haemoglobin response peaks, and induced peripheral autonomic reactions. The processing of positive and negative pictures enhanced haemodynamic response amplitude, and this effect was paralleled by blood pressure changes. The processing of positive pictures was reflected in reduced haemodynamic response peak latency. Together these data suggest that the early visual cortex holds amplitude-dependent representation of stimulus salience and latency-dependent information regarding stimulus valence, providing new insight into affective interaction with sensory processing.
Wednesday, September 02, 2009
ARTICLE UPDATE - Appetitive vs. defensive responses to emotional cues. Autonomic measures and brain oscillation modulation.
Balconi M, Brambilla E, Falbo L.
Brain Research, in press
The present study explored the effect of the subjective evaluation and the individual differences related to BIS and BAS (Behavioural Inhibition and Activation System) on autonomic measures and brain oscillations, in response to appetitive and aversive emotional stimuli. Multiple measures were recorded, such as psychophysiological (skin conductance response, heart rate, and electromyography) and frequency bands (delta, theta, alpha, and gamma), during viewing IAPS figures, that varied in terms of pleasantness (appetitive vs. aversive) and arousing power (high vs. low intensity). Both BIS and BAS measures were significant in modulating behavioural, autonomic and brain oscillations responses. Withdrawal (BIS system) and appetitive (BAS system) behaviour showed opposite patterns of responses by the subjects. Also, frontal cortical site response was more significant than other sites. Nevertheless, no specific lateralization effect was found as a function of BIS/BAS dichotomy. Moreover, autonomic variables and frequency band modulations were found to be effected by valence and arousal rating per se, with an increased response for high arousing and negative or positive stimuli in comparison with low arousing and neutral stimuli. The effects of subjective evaluation and individual differences were discussed at light of coping activity model of emotion comprehension.
Brain Research, in press
The present study explored the effect of the subjective evaluation and the individual differences related to BIS and BAS (Behavioural Inhibition and Activation System) on autonomic measures and brain oscillations, in response to appetitive and aversive emotional stimuli. Multiple measures were recorded, such as psychophysiological (skin conductance response, heart rate, and electromyography) and frequency bands (delta, theta, alpha, and gamma), during viewing IAPS figures, that varied in terms of pleasantness (appetitive vs. aversive) and arousing power (high vs. low intensity). Both BIS and BAS measures were significant in modulating behavioural, autonomic and brain oscillations responses. Withdrawal (BIS system) and appetitive (BAS system) behaviour showed opposite patterns of responses by the subjects. Also, frontal cortical site response was more significant than other sites. Nevertheless, no specific lateralization effect was found as a function of BIS/BAS dichotomy. Moreover, autonomic variables and frequency band modulations were found to be effected by valence and arousal rating per se, with an increased response for high arousing and negative or positive stimuli in comparison with low arousing and neutral stimuli. The effects of subjective evaluation and individual differences were discussed at light of coping activity model of emotion comprehension.
ARTICLE UPDATE - Brain oscillations and BIS/BAS (behavioral inhibition/activation system) effects on processing masked emotional cues ERS/ERD and cohe
Balconi M, Mazza G.
International Journal of Psychophysiology, in press
Alpha brain oscillation modulation was analyzed in response to masked emotional facial expressions. In addition, behavioural activation (BAS) and behavioural inhibition systems (BIS) were considered as an explicative factor to verify the effect of motivational significance on cortical activity. Nineteen subjects were submitted to an ample range of facial expressions of emotions (anger, fear, surprise, disgust, happiness, sadness, and neutral). The results demonstrated that anterior frontal sites were more active than central and posterior sites in response to facial stimuli. Moreover, right-side responses varied as a function of emotional types, with an increased right-frontal activity for negative emotions. Finally, whereas higher BIS subjects generated a more right hemisphere activation for some negative emotions (such as fear, anger, and surprise), Reward-BAS subjects were more responsive to positive emotion (happiness) within the left hemisphere. Valence and potential threatening power of facial expressions were considered to elucidate these cortical differences.
International Journal of Psychophysiology, in press
Alpha brain oscillation modulation was analyzed in response to masked emotional facial expressions. In addition, behavioural activation (BAS) and behavioural inhibition systems (BIS) were considered as an explicative factor to verify the effect of motivational significance on cortical activity. Nineteen subjects were submitted to an ample range of facial expressions of emotions (anger, fear, surprise, disgust, happiness, sadness, and neutral). The results demonstrated that anterior frontal sites were more active than central and posterior sites in response to facial stimuli. Moreover, right-side responses varied as a function of emotional types, with an increased right-frontal activity for negative emotions. Finally, whereas higher BIS subjects generated a more right hemisphere activation for some negative emotions (such as fear, anger, and surprise), Reward-BAS subjects were more responsive to positive emotion (happiness) within the left hemisphere. Valence and potential threatening power of facial expressions were considered to elucidate these cortical differences.
ARTICLE UPDATE - Changing Fear: The Neurocircuitry of Emotion Regulation.
Hartley CA, Phelps EA.
Neuropsychopharmacology, in press
The ability to alter emotional responses as circumstances change is a critical component of normal adaptive behavior and is often impaired in psychological disorders. In this review, we discuss four emotional regulation techniques that have been investigated as means to control fear: extinction, cognitive regulation, active coping, and reconsolidation. For each technique, we review what is known about the underlying neural systems, combining findings from animal models and human neuroscience. The current evidence suggests that these different means of regulating fear depend on both overlapping and distinct components of a fear circuitry.
Neuropsychopharmacology, in press
The ability to alter emotional responses as circumstances change is a critical component of normal adaptive behavior and is often impaired in psychological disorders. In this review, we discuss four emotional regulation techniques that have been investigated as means to control fear: extinction, cognitive regulation, active coping, and reconsolidation. For each technique, we review what is known about the underlying neural systems, combining findings from animal models and human neuroscience. The current evidence suggests that these different means of regulating fear depend on both overlapping and distinct components of a fear circuitry.
ARTICLE UPDATE - Emotional context modulates response inhibition: Neural and behavioral data.
Albert J, López-Martín S, Carretié L.
Neuroimage, in press
Although recent hemodynamic studies indicate that neural activity related to emotion and that associated with response inhibition constitute closely interrelated and mutually dependent processes, the nature of this relationship is still unclear. In order to explore the temporo-spatial characteristics of the interaction between emotion and inhibition, event-related potentials (ERPs) were measured as participants (N=30) performed a modified version of the Go/Nogo task that required the inhibition of prepotent responses to neutral cues during three different emotional contexts: negative, neutral, and positive. Temporal and spatial Principal Component Analyses were employed to detect and quantify, in a reliable manner, those ERP components related to response inhibition (i.e., Nogo-N2 and Nogo-P3), and a source-localization technique (sLORETA) provided information on their neural origin. Behavioral analyses revealed that reaction times (RTs) to Go cues were shorter during the positive context than during neutral and negative contexts. ERP analyses showed that suppressing responses to Nogo cues within the positive context elicited larger frontocentral Nogo-P3 amplitudes and enhanced anterior cingulate cortex (ACC) activation than within the negative context. Regression analyses revealed that Nogo-P3 (i) was inversely related to RTs, supporting its association with the inhibition of a prepotent response, and (ii) was associated with contextual valence (amplitude increased as context valence was more positive), but not with contextual arousal. These results suggest that withholding a prepotent response within positively valenced contexts is more difficult and requires more inhibitory control than within negatively valenced contexts.
Neuroimage, in press
Although recent hemodynamic studies indicate that neural activity related to emotion and that associated with response inhibition constitute closely interrelated and mutually dependent processes, the nature of this relationship is still unclear. In order to explore the temporo-spatial characteristics of the interaction between emotion and inhibition, event-related potentials (ERPs) were measured as participants (N=30) performed a modified version of the Go/Nogo task that required the inhibition of prepotent responses to neutral cues during three different emotional contexts: negative, neutral, and positive. Temporal and spatial Principal Component Analyses were employed to detect and quantify, in a reliable manner, those ERP components related to response inhibition (i.e., Nogo-N2 and Nogo-P3), and a source-localization technique (sLORETA) provided information on their neural origin. Behavioral analyses revealed that reaction times (RTs) to Go cues were shorter during the positive context than during neutral and negative contexts. ERP analyses showed that suppressing responses to Nogo cues within the positive context elicited larger frontocentral Nogo-P3 amplitudes and enhanced anterior cingulate cortex (ACC) activation than within the negative context. Regression analyses revealed that Nogo-P3 (i) was inversely related to RTs, supporting its association with the inhibition of a prepotent response, and (ii) was associated with contextual valence (amplitude increased as context valence was more positive), but not with contextual arousal. These results suggest that withholding a prepotent response within positively valenced contexts is more difficult and requires more inhibitory control than within negatively valenced contexts.
ARTICLE UPDATE - Personal space regulation by the human amygdala.
Kennedy DP, Gläscher J, Tyszka JM, Adolphs R.
Nature Neuroscience, in press
The amygdala plays key roles in emotion and social cognition, but how this translates to face-to-face interactions involving real people remains unknown. We found that an individual with complete amygdala lesions lacked any sense of personal space. Furthermore, healthy individuals showed amygdala activation upon close personal proximity. The amygdala may be required to trigger the strong emotional reactions normally following personal space violations, thus regulating interpersonal distance in humans.
Nature Neuroscience, in press
The amygdala plays key roles in emotion and social cognition, but how this translates to face-to-face interactions involving real people remains unknown. We found that an individual with complete amygdala lesions lacked any sense of personal space. Furthermore, healthy individuals showed amygdala activation upon close personal proximity. The amygdala may be required to trigger the strong emotional reactions normally following personal space violations, thus regulating interpersonal distance in humans.
Monday, August 24, 2009
ARTICLE UPDATE - When nonsense sounds happy or helpless: The Implicit Positive and Negative Affect Test (IPANAT).
Quirin M, Kazén M, Kuhl J.
Journal of Personality and Social Psychology, 97, 500-516
This article introduces an instrument for the indirect assessment of positive and negative affect, the Implicit Positive and Negative Affect Test (IPANAT). This test draws on participant ratings of the extent to which artificial words subjectively convey various emotions. Factor analyses of these ratings yielded two independent factors that can be interpreted as implicit positive and negative affect. The corresponding scales show adequate internal consistency, test-retest reliability, stability (Study 1), and construct validity (Study 2). Studies 3 and 4 demonstrate that the IPANAT also measures state variance. Finally, Study 5 provides criterion-based validity by demonstrating that correlations between implicit affect and explicit affect are higher under conditions of spontaneous responding than under conditions of reflective responding to explicit affect scales. The present findings suggest that the IPANAT is a reliable and valid measure with a straightforward application procedure.
Journal of Personality and Social Psychology, 97, 500-516
This article introduces an instrument for the indirect assessment of positive and negative affect, the Implicit Positive and Negative Affect Test (IPANAT). This test draws on participant ratings of the extent to which artificial words subjectively convey various emotions. Factor analyses of these ratings yielded two independent factors that can be interpreted as implicit positive and negative affect. The corresponding scales show adequate internal consistency, test-retest reliability, stability (Study 1), and construct validity (Study 2). Studies 3 and 4 demonstrate that the IPANAT also measures state variance. Finally, Study 5 provides criterion-based validity by demonstrating that correlations between implicit affect and explicit affect are higher under conditions of spontaneous responding than under conditions of reflective responding to explicit affect scales. The present findings suggest that the IPANAT is a reliable and valid measure with a straightforward application procedure.
ARTICLE UPDATE - Smile Through Your Fear and Sadness.
Smith FW, Schyns PG.
Psychological Science, in press
ABSTRACT- It is well established that animal communication signals have adapted to the evolutionary pressures of their environment. For example, the low-frequency vocalizations of the elephant are tailored to long-range communications, whereas the high-frequency trills of birds are adapted to their more localized acoustic niche. Like the voice, the human face transmits social signals about the internal emotional state of the transmitter. Here, we address two main issues: First, we characterized the spectral composition of the facial features signaling each of the six universal expressions of emotion (happiness, sadness, fear, disgust, anger, and surprise). From these analyses, we then predicted and tested the effectiveness of the transmission of emotion signals over different viewing distances. We reveal a gradient of recognition over viewing distances constraining the relative adaptive usefulness of facial expressions of emotion (distal expressions are good signals over a wide range of viewing distances; proximal expressions are suited to closer-range communication).
Psychological Science, in press
ABSTRACT- It is well established that animal communication signals have adapted to the evolutionary pressures of their environment. For example, the low-frequency vocalizations of the elephant are tailored to long-range communications, whereas the high-frequency trills of birds are adapted to their more localized acoustic niche. Like the voice, the human face transmits social signals about the internal emotional state of the transmitter. Here, we address two main issues: First, we characterized the spectral composition of the facial features signaling each of the six universal expressions of emotion (happiness, sadness, fear, disgust, anger, and surprise). From these analyses, we then predicted and tested the effectiveness of the transmission of emotion signals over different viewing distances. We reveal a gradient of recognition over viewing distances constraining the relative adaptive usefulness of facial expressions of emotion (distal expressions are good signals over a wide range of viewing distances; proximal expressions are suited to closer-range communication).
ARTICLE UPDATE - Response and habituation of the amygdala during processing of emotional prosody.
Wiethoff S, Wildgruber D, Grodd W, Ethofer T.
Neuroreport, in press
The role of the amygdala in processing acoustic information of affective value is still under debate. Using event-related functional MRI (fMRI), we showed increased amygdalar responses to various emotions (anger, fear, happiness, eroticism) expressed by prosody, a means of communication bound to language and consequently unique to humans. The smallest signal increases were found for fearful prosody, a finding that could not be explained by rapid response habituation to stimuli of this emotional category, challenging classical theories about fear specificity of the human amygdala. Our results converge with earlier neuroimaging evidence investigating emotional vocalizations, and these neurobiological similarities suggest that the two forms of communication might have common evolutionary roots.
Neuroreport, in press
The role of the amygdala in processing acoustic information of affective value is still under debate. Using event-related functional MRI (fMRI), we showed increased amygdalar responses to various emotions (anger, fear, happiness, eroticism) expressed by prosody, a means of communication bound to language and consequently unique to humans. The smallest signal increases were found for fearful prosody, a finding that could not be explained by rapid response habituation to stimuli of this emotional category, challenging classical theories about fear specificity of the human amygdala. Our results converge with earlier neuroimaging evidence investigating emotional vocalizations, and these neurobiological similarities suggest that the two forms of communication might have common evolutionary roots.
Monday, August 17, 2009
ARTICLE UPDATE - Distinct brain systems underlie the processing of valence and arousal of affective pictures.
Nielen MM, Heslenfeld DJ, Heinen K, Van Strien JW, Witter MP, Jonker C, Veltman DJ.
Brain & Cognition, in press
Valence and arousal are thought to be the primary dimensions of human emotion. However, the degree to which valence and arousal interact in determining brain responses to emotional pictures is still elusive. This functional MRI study aimed to delineate neural systems responding to valence and arousal, and their interaction. We measured neural activation in healthy females (N=23) to affective pictures using a 2 (Valence)x2 (Arousal) design. Results show that arousal was preferentially processed by middle temporal gyrus, hippocampus and ventrolateral prefrontal cortex. Regions responding to negative valence included visual and lateral prefrontal regions, positive valence activated middle temporal and orbitofrontal areas. Importantly, distinct arousal-by-valence interactions were present in anterior insula (negative pictures), and in occipital cortex, parahippocampal gyrus and posterior cingulate (positive pictures). These data demonstrate that the brain not only differentiates between valence and arousal but also responds to specific combinations of these two, thereby highlighting the sophisticated nature of emotion processing in (female) human subjects.
Brain & Cognition, in press
Valence and arousal are thought to be the primary dimensions of human emotion. However, the degree to which valence and arousal interact in determining brain responses to emotional pictures is still elusive. This functional MRI study aimed to delineate neural systems responding to valence and arousal, and their interaction. We measured neural activation in healthy females (N=23) to affective pictures using a 2 (Valence)x2 (Arousal) design. Results show that arousal was preferentially processed by middle temporal gyrus, hippocampus and ventrolateral prefrontal cortex. Regions responding to negative valence included visual and lateral prefrontal regions, positive valence activated middle temporal and orbitofrontal areas. Importantly, distinct arousal-by-valence interactions were present in anterior insula (negative pictures), and in occipital cortex, parahippocampal gyrus and posterior cingulate (positive pictures). These data demonstrate that the brain not only differentiates between valence and arousal but also responds to specific combinations of these two, thereby highlighting the sophisticated nature of emotion processing in (female) human subjects.
ARTICLE UPDATE - An electrophysiological investigation into the automaticity of emotional face processing in high versus low trait anxious individuals
Holmes A, Nielsen MK, Tipper S, Green S.
Cognitive, Affective, Behavioral Neuroscience, 9, 323-334
To examine the extent of automaticity of emotional face processing in high versus low trait anxious participants, event-related potentials (ERPs) were recorded to emotional (fearful, happy) and neutral faces under varying task demands (low load, high load). Results showed that perceptual encoding of emotional faces, as reflected in P1 and early posterior negativity components, was unaffected by the availability of processing resources. In contrast, the postperceptual registration and storage of emotion-related information, as reflected in the late positive potential component at frontal locations, was influenced by the availability of processing resources, and this effect was further modulated by level of trait anxiety. Specifically, frontal ERP augmentations to emotional faces were eliminated in the more demanding task for low trait anxious participants, whereas ERP enhancements to emotional faces were unaffected by task load in high trait anxious participants. This result suggests greater automaticity in processing affective information in high trait anxious participants.
Cognitive, Affective, Behavioral Neuroscience, 9, 323-334
To examine the extent of automaticity of emotional face processing in high versus low trait anxious participants, event-related potentials (ERPs) were recorded to emotional (fearful, happy) and neutral faces under varying task demands (low load, high load). Results showed that perceptual encoding of emotional faces, as reflected in P1 and early posterior negativity components, was unaffected by the availability of processing resources. In contrast, the postperceptual registration and storage of emotion-related information, as reflected in the late positive potential component at frontal locations, was influenced by the availability of processing resources, and this effect was further modulated by level of trait anxiety. Specifically, frontal ERP augmentations to emotional faces were eliminated in the more demanding task for low trait anxious participants, whereas ERP enhancements to emotional faces were unaffected by task load in high trait anxious participants. This result suggests greater automaticity in processing affective information in high trait anxious participants.
ARTICLE UPDATE - Taboo words: The effect of emotion on memory for peripheral information.
Guillet R, Arndt J.
Memory & Cognition, 37, 866-879
In three experiments, we examined memory for peripheral information that occurred in the same context as emotion-inducing information. In the first two experiments, participants studied either a sentence (Experiment 1) or a pair of words (Experiments 2A-2C) containing a neutral peripheral word, as well as a neutral, negative-valence, or taboo word, to induce an emotional response. At retrieval, the participants were asked to recall the neutral peripheral word from a sentence fragment or emotion-inducing word cue. In Experiment 3, we presented word pairs at encoding and tested memory with associative recognition. In all three experiments, memory for peripheral words was enhanced when it was encoded in the presence of emotionally arousing taboo words but not when it was encoded in the presence of words that were only negative in valence. These data are consistent with priority-binding theory (MacKay et al., 2004) and inconsistent with the attention-narrowing hypothesis (Easterbrook, 1959), as well as with object-based binding theory (Mather, 2007).
Memory & Cognition, 37, 866-879
In three experiments, we examined memory for peripheral information that occurred in the same context as emotion-inducing information. In the first two experiments, participants studied either a sentence (Experiment 1) or a pair of words (Experiments 2A-2C) containing a neutral peripheral word, as well as a neutral, negative-valence, or taboo word, to induce an emotional response. At retrieval, the participants were asked to recall the neutral peripheral word from a sentence fragment or emotion-inducing word cue. In Experiment 3, we presented word pairs at encoding and tested memory with associative recognition. In all three experiments, memory for peripheral words was enhanced when it was encoded in the presence of emotionally arousing taboo words but not when it was encoded in the presence of words that were only negative in valence. These data are consistent with priority-binding theory (MacKay et al., 2004) and inconsistent with the attention-narrowing hypothesis (Easterbrook, 1959), as well as with object-based binding theory (Mather, 2007).
Monday, August 10, 2009
ARTICLE UPDATE - Tuning the brain for novelty detection under emotional threat: the role of increasing gamma phase-synchronization.
Garcia-Garcia M, Yordanova J, Kolev V, Domínguez-Borràs J, Escera C.
Neuroimage, in press
Effective orienting of attention towards novel events is crucial for survival, particularly if they occur in a dangerous situation. This is why stimuli with emotional value are more efficient in capturing attention than neutral stimuli, and why the processing of unexpected novel stimuli is enhanced under a negative emotional context. Here we measured the phase-synchronization (PS) of gamma-band responses (GBR) from human EEG scalp-recordings during performance of a visual discrimination task in which task-irrelevant standard and novel sounds were presented in either a neutral or a negative emotional context, in order to elucidate the brain mechanisms by which emotion tunes the processing of novel events. Visual task performance was distracted by novel sounds, and this distraction was enhanced by the negative emotional context. Similarly, gamma PS was enhanced after novel as compared to standard sounds and it was also larger to auditory stimuli in the negative than in the neutral emotional context, reflecting the synchronization of neural networks for increasing of attentional processing. Remarkably, the larger PS increase of GBR after novel sounds in the negative as compared to the neutral emotional context over midline and right frontal regions reveals that a negative emotional context tunes novelty processing by means of the PS of brain activity in the gamma frequency band around 40 Hz in specific neural networks.
Neuroimage, in press
Effective orienting of attention towards novel events is crucial for survival, particularly if they occur in a dangerous situation. This is why stimuli with emotional value are more efficient in capturing attention than neutral stimuli, and why the processing of unexpected novel stimuli is enhanced under a negative emotional context. Here we measured the phase-synchronization (PS) of gamma-band responses (GBR) from human EEG scalp-recordings during performance of a visual discrimination task in which task-irrelevant standard and novel sounds were presented in either a neutral or a negative emotional context, in order to elucidate the brain mechanisms by which emotion tunes the processing of novel events. Visual task performance was distracted by novel sounds, and this distraction was enhanced by the negative emotional context. Similarly, gamma PS was enhanced after novel as compared to standard sounds and it was also larger to auditory stimuli in the negative than in the neutral emotional context, reflecting the synchronization of neural networks for increasing of attentional processing. Remarkably, the larger PS increase of GBR after novel sounds in the negative as compared to the neutral emotional context over midline and right frontal regions reveals that a negative emotional context tunes novelty processing by means of the PS of brain activity in the gamma frequency band around 40 Hz in specific neural networks.
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