Giussani C, Pirillo D, Roux FE.
Journal of Neurosurgery, in press
Object The capability of recognizing the expressions of facial emotions has been hypothesized to depend on a right hemispheric cortical-subcortical network. Its impairment deeply disturbs social relationships. To spare right hemispheric cortical areas involved in recognizing facial emotion, the authors used intraoperative cortical stimulation and the awake surgery technique in a consecutive series of patients. The feasibility and the interest to map them during brain mapping for neurosurgical procedures are discussed. Methods After a preoperative neuropsychological evaluation, 18 consecutive patients with right hemispheric lesions (5 metastases, 6 high-grade gliomas, 4 low-grade gliomas, 2 arteriovenous malformations, and 1 malignant meningioma) were tested by intraoperative cortical stimulation while performing a facial emotion recognition task along with sensorimotor and visuospatial tasks. Results Three hundred eighty-six cortical sites were studied. Five (1.30%) reproducible interference sites for facial emotion recognition were identified in 5 patients: 1 site in the medial segment of T1; 1 site in the posterior segment of T1; 1 site in the posterior segment of T2; and 2 sites in the supramarginal gyrus. No selective impairment was found regarding the emotion category. All facial emotion recognition sites were spared during surgery, and none of the patients experienced postoperative deficits in recognition of facial emotions. Conclusions The finding of interference sites in facial emotion recognition in the right posterior perisylvian area, independent to sensorimotor or visuospatial orientation processes, reinforces the theory about the role of anatomically and functionally segregated right hemisphere structures in this cognitive process. The authors advocate offering a brain mapping of facial emotion recognition to patients with right posterior perisylvian tumors.
Saturday, June 27, 2009
ARTICLE UPDATE - Influence of attention to somatic information on emotional and autonomic responses.
Murakami H, Ohira H, Matsunaga M, Kimura K.
Perceptual Motor Skills, 108, 531-539
The present study aimed to investigate the dissociable effects of two forms of self-focus on emotional and autonomic responses. One form is suppression, which includes the suppression of heart rate and self-evaluation of performance. The other is observation, which includes attention to one's own heart rate with no suppression and no evaluation. 26 undergraduate and graduate students from the Nagoya University campus (13 men, 13 women), ages 18 to 24 years (M = 20.7, SD = 1.6) were recruited. Participants were provided with their own heart rate as feedback for 5 min., during which participants conducted a self-focus manipulation. Several days after the experimental session for one condition, the same participants conducted another experimental session for the other condition. Instruction to suppress enhanced physiological arousal and subsequent negative emotions; however, instruction to observe did not increase physiological arousal or negative emotions.
Perceptual Motor Skills, 108, 531-539
The present study aimed to investigate the dissociable effects of two forms of self-focus on emotional and autonomic responses. One form is suppression, which includes the suppression of heart rate and self-evaluation of performance. The other is observation, which includes attention to one's own heart rate with no suppression and no evaluation. 26 undergraduate and graduate students from the Nagoya University campus (13 men, 13 women), ages 18 to 24 years (M = 20.7, SD = 1.6) were recruited. Participants were provided with their own heart rate as feedback for 5 min., during which participants conducted a self-focus manipulation. Several days after the experimental session for one condition, the same participants conducted another experimental session for the other condition. Instruction to suppress enhanced physiological arousal and subsequent negative emotions; however, instruction to observe did not increase physiological arousal or negative emotions.
ARTICLE UPDATE - Worry tendencies predict brain activation during aversive imagery.
Schienle A, Schäfer A, Pignanelli R, Vaitl D.
Neuroscience Letters, in press
Because of its abstract nature, worrying might function as an avoidance response in order to cognitively disengage from fearful imagery. The present functional magnetic resonance imaging study investigated neural correlates of aversive imagery and their association with worry tendencies, as measured by the Penn State Worry Questionnaire (PSWQ). Nineteen healthy women first viewed, and subsequently imagined pictures from two categories, 'threat' and 'happiness'. Worry tendencies were negatively correlated with brain activation in the anterior cingulate cortex, the prefrontal cortex (dorsolateral, dorsomedial, ventrolateral), the parietal cortex and the insula. These negative correlations between PSWQ scores and localized brain activation were specific for aversive imagery. Moreover, activation in the abovementioned regions was positively associated with the experienced vividness of both pleasant and unpleasant mental pictures. As the identified brain regions are involved in emotion regulation, vivid imagery and memory retrieval, a lowered activity in high PSWQ scorers might be associated with cognitive disengagement from aversive imagery as well as insufficient refresh rates of mental pictures. Our preliminary findings encourage future imagery studies on generalized anxiety disorder patients, as one of the main symptoms of this disorder is excessive worrying.
Neuroscience Letters, in press
Because of its abstract nature, worrying might function as an avoidance response in order to cognitively disengage from fearful imagery. The present functional magnetic resonance imaging study investigated neural correlates of aversive imagery and their association with worry tendencies, as measured by the Penn State Worry Questionnaire (PSWQ). Nineteen healthy women first viewed, and subsequently imagined pictures from two categories, 'threat' and 'happiness'. Worry tendencies were negatively correlated with brain activation in the anterior cingulate cortex, the prefrontal cortex (dorsolateral, dorsomedial, ventrolateral), the parietal cortex and the insula. These negative correlations between PSWQ scores and localized brain activation were specific for aversive imagery. Moreover, activation in the abovementioned regions was positively associated with the experienced vividness of both pleasant and unpleasant mental pictures. As the identified brain regions are involved in emotion regulation, vivid imagery and memory retrieval, a lowered activity in high PSWQ scorers might be associated with cognitive disengagement from aversive imagery as well as insufficient refresh rates of mental pictures. Our preliminary findings encourage future imagery studies on generalized anxiety disorder patients, as one of the main symptoms of this disorder is excessive worrying.
Friday, June 19, 2009
ARTICLE UPDATE - In search of specificity: functional MRI in the study of emotional experience.
Schienle A, Schäfer A.
International Journal of Psychophysiology, 73, 22-26.
The growing availability of functional magnetic resonance imaging (fMRI) with its property of high spatial resolution has energized the search for specific neural substrates of basic emotions and their feeling components. In the present article, we address the question as to whether recent fMRI studies on primary affective experiences have truly helped to pinpoint emotion-specific areas in the human brain or whether these studies are afflicted with methodological problems which make such inferences difficult. As one approach for improvement, we suggest the combination of fMRI with methods characterized by high temporal resolution, such as electroencephalography (EEG). Simultaneous recoding allows the correlation of temporally specific EEG components (e.g., the late positive potential) with regional blood-oxygen-level-dependent (BOLD) signals during affective experiences. Combined information on the source as well as the exact temporal pattern of a neural affective response will help to improve our understanding of emotion-specific brain activation.
International Journal of Psychophysiology, 73, 22-26.
The growing availability of functional magnetic resonance imaging (fMRI) with its property of high spatial resolution has energized the search for specific neural substrates of basic emotions and their feeling components. In the present article, we address the question as to whether recent fMRI studies on primary affective experiences have truly helped to pinpoint emotion-specific areas in the human brain or whether these studies are afflicted with methodological problems which make such inferences difficult. As one approach for improvement, we suggest the combination of fMRI with methods characterized by high temporal resolution, such as electroencephalography (EEG). Simultaneous recoding allows the correlation of temporally specific EEG components (e.g., the late positive potential) with regional blood-oxygen-level-dependent (BOLD) signals during affective experiences. Combined information on the source as well as the exact temporal pattern of a neural affective response will help to improve our understanding of emotion-specific brain activation.
Saturday, June 13, 2009
ARTICLE UPDATE - Emotions in motion: Dynamic compared to static facial expressions of disgust and happiness reveal more widespread emotion-specific ac
Emotions in motion: Dynamic compared to static facial expressions of disgust and happiness reveal more widespread emotion-specific activations.
Brain Research, in press
In social contexts, facial expressions are dynamic in nature and vary rapidly in relation to situational requirements. However, there are very few fMRI studies using dynamic emotional stimuli. The aim of this study was (1) to introduce and evaluate a new stimulus database of static and dynamic emotional facial expressions according to arousal and recognizability investigated by a rating by both participants of the present fMRI study and by an external sample of 30 healthy women, (2) to examine the neural networks involved in emotion perception of static and dynamic facial stimuli separately, and (3) to examine the impact of motion on the emotional processing of dynamic compared to static face stimuli. A total of 16 females participated in the present fMRI study performing a passive emotion perception task including static and dynamic faces of neutral, happy and disgusted expressions. Comparing dynamic stimuli to static faces indicated enhanced emotion-specific brain activation patterns in the parahippocampal gyrus (PHG) including the amygdala (AMG), fusiform gyrus (FG), superior temporal gyrus (STG), inferior frontal gyrus (IFG), and occipital and orbitofrontal cortex (OFC). These regions have been discussed to be associated with emotional memory encoding, the perception of threat, facial identity, biological motion, the mirror neuron system, an increase of emotional arousal, and reward processing, respectively. Post hoc ratings of the dynamic stimuli revealed a better recognizability in comparison to the static stimuli. In conclusion, dynamic facial expressions might provide a more appropriate approach to examine the processing of emotional face perception than static stimuli.
Brain Research, in press
In social contexts, facial expressions are dynamic in nature and vary rapidly in relation to situational requirements. However, there are very few fMRI studies using dynamic emotional stimuli. The aim of this study was (1) to introduce and evaluate a new stimulus database of static and dynamic emotional facial expressions according to arousal and recognizability investigated by a rating by both participants of the present fMRI study and by an external sample of 30 healthy women, (2) to examine the neural networks involved in emotion perception of static and dynamic facial stimuli separately, and (3) to examine the impact of motion on the emotional processing of dynamic compared to static face stimuli. A total of 16 females participated in the present fMRI study performing a passive emotion perception task including static and dynamic faces of neutral, happy and disgusted expressions. Comparing dynamic stimuli to static faces indicated enhanced emotion-specific brain activation patterns in the parahippocampal gyrus (PHG) including the amygdala (AMG), fusiform gyrus (FG), superior temporal gyrus (STG), inferior frontal gyrus (IFG), and occipital and orbitofrontal cortex (OFC). These regions have been discussed to be associated with emotional memory encoding, the perception of threat, facial identity, biological motion, the mirror neuron system, an increase of emotional arousal, and reward processing, respectively. Post hoc ratings of the dynamic stimuli revealed a better recognizability in comparison to the static stimuli. In conclusion, dynamic facial expressions might provide a more appropriate approach to examine the processing of emotional face perception than static stimuli.
ARTICLE UPDATE - Emotion and space. Lateralized emotional word detection depends on line bisection bias.
Tamagni C, Mantei T, Brugger P.
Neuroscience, in press
There is converging evidence, from various independent areas of neuroscience, for a functional specialization of the left and right cerebral hemispheres for positive and negative emotions, respectively ("valence theory" of emotional processing). One subfield, however, has produced mixed results, i.e. work on the detection of parafoveally presented positively or negatively emotional words by healthy subjects. Right or left visual field advantages were described and interpreted as reflecting the superiority of either the left hemisphere (LH) for linguistic material, or of the right hemisphere (RH) for highly emotional stimuli. Here we show that 48 healthy, right-handed participants' performance on a lateralized lexical decision task depends on their individual inclination to bisect a line to the left or right of the objective center. Only those with a bisection bias to the right showed the LH advantage for word detection known from the neuropsychological literature. Negative emotional words were processed with comparable accuracy in the two visual fields. However, a recognition advantage for negative over positive emotional words was found exclusively for those participants with a leftward line bisection bias. These results suggest that in work on functional hemispheric differences state variables like stimulus lateralization and word emotionality may be less decisive than the trait variable of lateral hemispatial attention. We propose a cautious reconsideration of the concept of "hemisphericity", which once emphasized individual differences in baseline hemispheric arousal, but was later dismissed in a reaction to oversimplifications in popular science accounts.
Neuroscience, in press
There is converging evidence, from various independent areas of neuroscience, for a functional specialization of the left and right cerebral hemispheres for positive and negative emotions, respectively ("valence theory" of emotional processing). One subfield, however, has produced mixed results, i.e. work on the detection of parafoveally presented positively or negatively emotional words by healthy subjects. Right or left visual field advantages were described and interpreted as reflecting the superiority of either the left hemisphere (LH) for linguistic material, or of the right hemisphere (RH) for highly emotional stimuli. Here we show that 48 healthy, right-handed participants' performance on a lateralized lexical decision task depends on their individual inclination to bisect a line to the left or right of the objective center. Only those with a bisection bias to the right showed the LH advantage for word detection known from the neuropsychological literature. Negative emotional words were processed with comparable accuracy in the two visual fields. However, a recognition advantage for negative over positive emotional words was found exclusively for those participants with a leftward line bisection bias. These results suggest that in work on functional hemispheric differences state variables like stimulus lateralization and word emotionality may be less decisive than the trait variable of lateral hemispatial attention. We propose a cautious reconsideration of the concept of "hemisphericity", which once emphasized individual differences in baseline hemispheric arousal, but was later dismissed in a reaction to oversimplifications in popular science accounts.
ARTICLE UPDATE - EEG coherence in humans: relationship with success in recognizing emotions in the voice.
Kislova OO, Rusalova MN.
Neuroscience and Behavioral Physiology, in press
EEG recordings from two groups of subjects - with high and low levels of recognition of emotions from voices were made. Comparisons were performed of the numbers of pairs of leads with different levels of coherence in baseline conditions and on recognition of emotions in six standard frequency ranges and in individual bands with 1-Hz steps. Significant differences were seen between groups 1 and 2 both in baseline conditions and during recognition of emotions: in most cases, coherence was greater in subjects with poor recognition of emotions from voices.
Neuroscience and Behavioral Physiology, in press
EEG recordings from two groups of subjects - with high and low levels of recognition of emotions from voices were made. Comparisons were performed of the numbers of pairs of leads with different levels of coherence in baseline conditions and on recognition of emotions in six standard frequency ranges and in individual bands with 1-Hz steps. Significant differences were seen between groups 1 and 2 both in baseline conditions and during recognition of emotions: in most cases, coherence was greater in subjects with poor recognition of emotions from voices.
Saturday, June 06, 2009
ARTICLE UPDATE - Prolonged reduction of electrocortical activity predicts correct performance during rapid serial visual processing.
Keil A, Heim S.
Psychophysiology, in press
Abstract When two targets are shown in a rapid temporal stream of distractors, performance for the second target (T2) is typically reduced when presented between 200 and 500 ms after the first (T1). The present study used the steady-state visual evoked potential (ssVEP), a continuous index of electrocortical facilitation, to compare brain responses in trials with correct versus incorrect T2 responses. We found a reduction of the electrocortical response following T1 in trials with correct T2 identification. By contrast, incorrect T2 trials were characterized by enhanced electrocortical amplitude. Amplitude attenuation predictive of successful T2 report was sustained over time, suggesting a reduction of resources allocated to the distractor stream in correct trials. Across intertarget intervals, T2 performance was a linear function of the ssVEP amplitude reduction in correct trials, weighted by the stimulus onset asynchrony.
Psychophysiology, in press
Abstract When two targets are shown in a rapid temporal stream of distractors, performance for the second target (T2) is typically reduced when presented between 200 and 500 ms after the first (T1). The present study used the steady-state visual evoked potential (ssVEP), a continuous index of electrocortical facilitation, to compare brain responses in trials with correct versus incorrect T2 responses. We found a reduction of the electrocortical response following T1 in trials with correct T2 identification. By contrast, incorrect T2 trials were characterized by enhanced electrocortical amplitude. Amplitude attenuation predictive of successful T2 report was sustained over time, suggesting a reduction of resources allocated to the distractor stream in correct trials. Across intertarget intervals, T2 performance was a linear function of the ssVEP amplitude reduction in correct trials, weighted by the stimulus onset asynchrony.
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