Schacht A, Sommer W.
Cognitive, Affective and Behavioral Neuroscience, 8, 28-43
The emotional content of stimuli influences cognitive performance. In two experiments, we investigated the time course and mechanisms of emotional influences on visual word processing in various tasks by recording event-related brain potentials (ERPs). The stimuli were verbs of positive, negative, and neutral valence. In Experiment 1, where lexical decisions had to be performed on single verbs, both positive and negative verbs were processed more quickly than neutral verbs and elicited a distinct ERP component, starting around 370 msec. In Experiment 2, the verbs were embedded in a semantic context provided by single nouns. Likewise, structural, lexical, and semantic decisions for positive verbs were accelerated, and an ERP effect with a scalp distribution comparable to that in Experiment 1 now started about 200 msec earlier. These effects may signal an automatic allocation of attentional resources to emotionally arousing words, since they were not modulated by different task demands. In contrast, a later ERP effect of emotion was restricted to lexical and semantic decisions and, thus, appears to indicate more elaborated, task-dependent processing of emotional words.
Showing posts with label erp. Show all posts
Showing posts with label erp. Show all posts
Saturday, February 28, 2009
Friday, February 13, 2009
ARTICLE UPDATE - Motivated and controlled attention to emotion: Time-course of the late positive potential.
Hajcak G, Dunning JP, Foti D.
Clinical Neurophysiology, in press
OBJECTIVE: The present study examined the time-course of automatic and controlled modulation of the late positive potential (LPP) during emotional picture viewing. METHODS: Participants (N=32) viewed neutral and unpleasant stimuli for 6000ms; at 3000ms, one of two tones signaled participants to attend either to a more or less arousing portion of the picture. The time-course of the LPP was examined both during the passive viewing and directed attention portions of the trial using the method proposed by Guthrie and Buchwald [Guthrie D, Buchwald JS. Significance testing of difference potentials. Psychophysiology 1991;28(2):240-4]. RESULTS: During passive viewing, the LPP became reliably larger following the presentation of unpleasant pictures from 160ms onward; the magnitude of the LPP became reliably smaller beginning 620ms after participants were instructed to attend to the less arousing aspects of unpleasant pictures - and this difference was maintained throughout the duration of the trial. CONCLUSIONS: The LPP reflects relatively automatic attention to emotional visual stimuli, but is also sensitive to manipulations of directed attention toward arousing versus neutral aspects of such stimuli. SIGNIFICANCE: These results shed further light on the time-course of emotional and cognitive modulation of the LPP, and suggest that the LPP reflects the relatively rapid and dynamic allocation of increased attention to emotional stimuli.
Clinical Neurophysiology, in press
OBJECTIVE: The present study examined the time-course of automatic and controlled modulation of the late positive potential (LPP) during emotional picture viewing. METHODS: Participants (N=32) viewed neutral and unpleasant stimuli for 6000ms; at 3000ms, one of two tones signaled participants to attend either to a more or less arousing portion of the picture. The time-course of the LPP was examined both during the passive viewing and directed attention portions of the trial using the method proposed by Guthrie and Buchwald [Guthrie D, Buchwald JS. Significance testing of difference potentials. Psychophysiology 1991;28(2):240-4]. RESULTS: During passive viewing, the LPP became reliably larger following the presentation of unpleasant pictures from 160ms onward; the magnitude of the LPP became reliably smaller beginning 620ms after participants were instructed to attend to the less arousing aspects of unpleasant pictures - and this difference was maintained throughout the duration of the trial. CONCLUSIONS: The LPP reflects relatively automatic attention to emotional visual stimuli, but is also sensitive to manipulations of directed attention toward arousing versus neutral aspects of such stimuli. SIGNIFICANCE: These results shed further light on the time-course of emotional and cognitive modulation of the LPP, and suggest that the LPP reflects the relatively rapid and dynamic allocation of increased attention to emotional stimuli.
Saturday, December 06, 2008
ARTICLE UPDATE - Attentional selectivity for emotional faces: Evidence from human electrophysiology.
Holmes A, Bradley BP, Kragh Nielsen M, Mogg K.
Psychophysiology, in press
Abstract This study investigated the temporal course of attentional biases for threat-related (angry) and positive (happy) facial expressions. Electrophysiological (event-related potential) and behavioral (reaction time [RT]) data were recorded while participants viewed pairs of faces (e.g., angry face paired with neutral face) shown for 500 ms and followed by a probe. Behavioral results indicated that RTs were faster to probes replacing emotional versus neutral faces, consistent with an attentional bias for emotional information. Electrophysiological results revealed that attentional orienting to threatening faces emerged earlier (early N2pc time window; 180-250 ms) than orienting to positive faces (after 250 ms), and that attention was sustained toward emotional faces during the 250-500-ms time window (late N2pc and SPCN components). These findings are consistent with models of attention and emotion that posit rapid attentional prioritization of threat.
Psychophysiology, in press
Abstract This study investigated the temporal course of attentional biases for threat-related (angry) and positive (happy) facial expressions. Electrophysiological (event-related potential) and behavioral (reaction time [RT]) data were recorded while participants viewed pairs of faces (e.g., angry face paired with neutral face) shown for 500 ms and followed by a probe. Behavioral results indicated that RTs were faster to probes replacing emotional versus neutral faces, consistent with an attentional bias for emotional information. Electrophysiological results revealed that attentional orienting to threatening faces emerged earlier (early N2pc time window; 180-250 ms) than orienting to positive faces (after 250 ms), and that attention was sustained toward emotional faces during the 250-500-ms time window (late N2pc and SPCN components). These findings are consistent with models of attention and emotion that posit rapid attentional prioritization of threat.
Saturday, November 22, 2008
ARTICLE UPDATE - See no evil: Directing visual attention within unpleasant images modulates the electrocortical response.
Dunning JP, Hajcak G.
Psychophysiology, in press
The late positive potential (LPP) is larger for emotional than neutral stimuli, and reflects increased attention to motivationally salient stimuli. Recent studies have shown that the LPP can also be modulated by stimulus meaning and task relevance. The present studies sought to determine whether the magnitude of the LPP can be manipulated by directing attention to more or less arousing aspects within an emotional stimulus. To this end, trials included a passive viewing and directed attention portion. In both Studies 1 and 2, unpleasant compared to neutral images were associated with an increased LPP during passive viewing; additionally, directing attention to non-arousing compared to highly arousing areas of unpleasant images resulted in a decreased LPP. Results are discussed in terms of the utility of using the LPP to understand emotion-cognition interactions, especially with regard to directed visual attention as an emotion regulation strategy.
Psychophysiology, in press
The late positive potential (LPP) is larger for emotional than neutral stimuli, and reflects increased attention to motivationally salient stimuli. Recent studies have shown that the LPP can also be modulated by stimulus meaning and task relevance. The present studies sought to determine whether the magnitude of the LPP can be manipulated by directing attention to more or less arousing aspects within an emotional stimulus. To this end, trials included a passive viewing and directed attention portion. In both Studies 1 and 2, unpleasant compared to neutral images were associated with an increased LPP during passive viewing; additionally, directing attention to non-arousing compared to highly arousing areas of unpleasant images resulted in a decreased LPP. Results are discussed in terms of the utility of using the LPP to understand emotion-cognition interactions, especially with regard to directed visual attention as an emotion regulation strategy.
ARTICLE UPDATE - Electrophysiological correlates of decreasing and increasing emotional responses to unpleasant pictures.
Moser JS, Krompinger JW, Dietz J, Simons RF.
Psychophysiology, in press
We examined event-related brain potential (ERP) modulations during the anticipation and processing of unpleasant pictures under instructions to cognitively decrease and increase negative emotion. Instructions to decrease and increase negative emotion modulated the ERP response to unpleasant pictures in the direction of emotional intensity beginning around 400 ms and lasting several seconds. Decrease, but not increase, instructions also elicited enhanced frontal negativity associated with orienting and preparation prior to unpleasant picture onset. Last, ERP modulation by unpleasant pictures began around 300 ms, just prior to regulation effects, suggesting that appraisal of emotion occurs before emotion regulation. Together, the current findings underscore the utility of ERPs in illuminating the time course of emotion modulation and regulation that may help to refine extant theoretical models.
Psychophysiology, in press
We examined event-related brain potential (ERP) modulations during the anticipation and processing of unpleasant pictures under instructions to cognitively decrease and increase negative emotion. Instructions to decrease and increase negative emotion modulated the ERP response to unpleasant pictures in the direction of emotional intensity beginning around 400 ms and lasting several seconds. Decrease, but not increase, instructions also elicited enhanced frontal negativity associated with orienting and preparation prior to unpleasant picture onset. Last, ERP modulation by unpleasant pictures began around 300 ms, just prior to regulation effects, suggesting that appraisal of emotion occurs before emotion regulation. Together, the current findings underscore the utility of ERPs in illuminating the time course of emotion modulation and regulation that may help to refine extant theoretical models.
ARTICLE UPDATE - Rapid influence of emotional scenes on encoding of facial expressions: an ERP study.
Righart R, de Gelder B.
Social, Cognitive, Affective Neuroscience, 3, 270-278
In daily life, we perceive a person's facial reaction as part of the natural environment surrounding it. Because most studies have investigated how facial expressions are recognized by using isolated faces, it is unclear what role the context plays. Although it has been observed that the N170 for facial expressions is modulated by the emotional context, it was not clear whether individuals use context information on this stage of processing to discriminate between facial expressions. The aim of the present study was to investigate how the early stages of face processing are affected by emotional scenes when explicit categorizations of fearful and happy facial expressions are made. Emotion effects were found for the N170, with larger amplitudes for faces in fearful scenes as compared to faces in happy and neutral scenes. Critically, N170 amplitudes were significantly increased for fearful faces in fearful scenes as compared to fearful faces in happy scenes and expressed in left-occipito-temporal scalp topography differences. Our results show that the information provided by the facial expression is combined with the scene context during the early stages of face processing
Social, Cognitive, Affective Neuroscience, 3, 270-278
In daily life, we perceive a person's facial reaction as part of the natural environment surrounding it. Because most studies have investigated how facial expressions are recognized by using isolated faces, it is unclear what role the context plays. Although it has been observed that the N170 for facial expressions is modulated by the emotional context, it was not clear whether individuals use context information on this stage of processing to discriminate between facial expressions. The aim of the present study was to investigate how the early stages of face processing are affected by emotional scenes when explicit categorizations of fearful and happy facial expressions are made. Emotion effects were found for the N170, with larger amplitudes for faces in fearful scenes as compared to faces in happy and neutral scenes. Critically, N170 amplitudes were significantly increased for fearful faces in fearful scenes as compared to fearful faces in happy scenes and expressed in left-occipito-temporal scalp topography differences. Our results show that the information provided by the facial expression is combined with the scene context during the early stages of face processing
Saturday, October 11, 2008
ARTICLE UPDATE - Trouble crossing the bridge: Altered interhemispheric communication of emotional images in anxiety.
Compton RJ, Carp J, Chaddock L, Fineman SL, Quandt LC, Ratliff JB.
Emotion, 8, 684-692.
Worry is thought to involve a strategy of cognitive avoidance, in which internal verbalization acts to suppress threatening emotional imagery. This study tested the hypothesis that worry-prone individuals would exhibit patterns of between-hemisphere communication that reflect cognitive avoidance. Specifically, the hypothesis predicted slower transfer of threatening images from the left to the right hemisphere among worriers. Event-related potential (ERP) measures of interhemispheric transfer time supported this prediction. Left-to-right hemisphere transfer times for angry faces were relatively slower for individuals scoring high in self-reported worry compared with those scoring low, whereas transfer of happy and neutral faces did not differ between groups. These results suggest that altered interhemispheric communication may constitute one mechanism of cognitive avoidance in worry.
Emotion, 8, 684-692.
Worry is thought to involve a strategy of cognitive avoidance, in which internal verbalization acts to suppress threatening emotional imagery. This study tested the hypothesis that worry-prone individuals would exhibit patterns of between-hemisphere communication that reflect cognitive avoidance. Specifically, the hypothesis predicted slower transfer of threatening images from the left to the right hemisphere among worriers. Event-related potential (ERP) measures of interhemispheric transfer time supported this prediction. Left-to-right hemisphere transfer times for angry faces were relatively slower for individuals scoring high in self-reported worry compared with those scoring low, whereas transfer of happy and neutral faces did not differ between groups. These results suggest that altered interhemispheric communication may constitute one mechanism of cognitive avoidance in worry.
ARTICLE UPDATE - Interpretation bias in social anxiety as detected by event-related brain potentials.
Moser JS, Hajcak G, Huppert JD, Foa EB, Simons RF.
Emotion, 8, 693-700
Little is known about psychophysiological correlates of interpretation bias in social anxiety. To address this issue, the authors measured event-related brain potentials (ERPs) in high and low socially anxious individuals during a task wherein ambiguous scenarios were resolved with either a positive or negative ending. Specifically, the authors examined modulations of the P600, an ERP that peaks approximately 600 ms following stimulus onset and indexes violations of expectancy. Low-anxious individuals were characterized by an increased P600 to negative in comparison with positive sentence endings, suggesting a positive interpretation bias. In contrast, the high-anxious group evidenced equivalent P600 magnitude for negative and positive sentence endings, suggesting a lack of positive interpretation bias. Similar, but less reliable results emerged in earlier time windows, that is, 200-500 ms poststimulus. Reaction time, occurring around 900 ms poststimulus, failed to show a reliable interpretation bias. Results suggest that ERPs can detect interpretation biases in social anxiety before the emission of behavioral responses.
Emotion, 8, 693-700
Little is known about psychophysiological correlates of interpretation bias in social anxiety. To address this issue, the authors measured event-related brain potentials (ERPs) in high and low socially anxious individuals during a task wherein ambiguous scenarios were resolved with either a positive or negative ending. Specifically, the authors examined modulations of the P600, an ERP that peaks approximately 600 ms following stimulus onset and indexes violations of expectancy. Low-anxious individuals were characterized by an increased P600 to negative in comparison with positive sentence endings, suggesting a positive interpretation bias. In contrast, the high-anxious group evidenced equivalent P600 magnitude for negative and positive sentence endings, suggesting a lack of positive interpretation bias. Similar, but less reliable results emerged in earlier time windows, that is, 200-500 ms poststimulus. Reaction time, occurring around 900 ms poststimulus, failed to show a reliable interpretation bias. Results suggest that ERPs can detect interpretation biases in social anxiety before the emission of behavioral responses.
Sunday, August 24, 2008
ARTICLE UPDATE - Affective valence, stimulus attributes, and P300: Color vs. black/white and normal vs. scrambled images.
Cano ME, Class QA, Polich J.
International Journal of Psychophysiology, in press
Pictures from the International Affective Picture System (IAPS) were selected to manipulate affective valence (unpleasant, neutral, pleasant) while keeping arousal level the same. The pictures were presented in an oddball paradigm, with a visual pattern used as the standard stimulus. Subjects pressed a button whenever a target was detected. Experiment 1 presented normal pictures in color and black/white. Control stimuli were constructed for both the color and black/white conditions by randomly rearranging 1 cm square fragments of each original picture to produce a "scrambled" image. Experiment 2 presented the same normal color pictures with large, medium, and small scrambled condition (2, 1, and 0.5 cm squares). The P300 event-related brain potential demonstrated larger amplitudes over frontal areas for positive compared to negative or neutral images for normal color pictures in both experiments. Attenuated and nonsignificant valence effects were obtained for black/white images. Scrambled stimuli in each study yielded no valence effects but demonstrated typical P300 topography that increased from frontal to parietal areas. The findings suggest that P300 amplitude is sensitive to affective picture valence in the absence of stimulus arousal differences, and that stimulus color contributes to ERP valence effects.
International Journal of Psychophysiology, in press
Pictures from the International Affective Picture System (IAPS) were selected to manipulate affective valence (unpleasant, neutral, pleasant) while keeping arousal level the same. The pictures were presented in an oddball paradigm, with a visual pattern used as the standard stimulus. Subjects pressed a button whenever a target was detected. Experiment 1 presented normal pictures in color and black/white. Control stimuli were constructed for both the color and black/white conditions by randomly rearranging 1 cm square fragments of each original picture to produce a "scrambled" image. Experiment 2 presented the same normal color pictures with large, medium, and small scrambled condition (2, 1, and 0.5 cm squares). The P300 event-related brain potential demonstrated larger amplitudes over frontal areas for positive compared to negative or neutral images for normal color pictures in both experiments. Attenuated and nonsignificant valence effects were obtained for black/white images. Scrambled stimuli in each study yielded no valence effects but demonstrated typical P300 topography that increased from frontal to parietal areas. The findings suggest that P300 amplitude is sensitive to affective picture valence in the absence of stimulus arousal differences, and that stimulus color contributes to ERP valence effects.
Saturday, August 02, 2008
ARTICLE UPDATE - The selective processing of emotional visual stimuli while detecting auditory targets: An ERP analysis.
Schupp HT, Stockburger J, Bublatzky F, Junghöfer M, Weike AI, Hamm AO.
Brain Research, in press
Event-related potential studies revealed an early posterior negativity (EPN) for emotional compared to neutral pictures. Exploring the emotion-attention relationship, a previous study observed that a primary visual discrimination task interfered with the emotional modulation of the EPN component. To specify the locus of interference, the present study assessed the fate of selective visual emotion processing while attention is directed towards the auditory modality. While simply viewing a rapid and continuous stream of pleasant, neutral, and unpleasant pictures in one experimental condition, processing demands of a concurrent auditory target discrimination task were systematically varied in three further experimental conditions. Participants successfully performed the auditory task as revealed by behavioral performance and selected event-related potential components. Replicating previous results, emotional pictures were associated with a larger posterior negativity compared to neutral pictures. Of main interest, increasing demands of the auditory task did not modulate the selective processing of emotional visual stimuli. With regard to the locus of interference, selective emotion processing as indexed by the EPN does not seem to reflect shared processing resources of visual and auditory modality.
Brain Research, in press
Event-related potential studies revealed an early posterior negativity (EPN) for emotional compared to neutral pictures. Exploring the emotion-attention relationship, a previous study observed that a primary visual discrimination task interfered with the emotional modulation of the EPN component. To specify the locus of interference, the present study assessed the fate of selective visual emotion processing while attention is directed towards the auditory modality. While simply viewing a rapid and continuous stream of pleasant, neutral, and unpleasant pictures in one experimental condition, processing demands of a concurrent auditory target discrimination task were systematically varied in three further experimental conditions. Participants successfully performed the auditory task as revealed by behavioral performance and selected event-related potential components. Replicating previous results, emotional pictures were associated with a larger posterior negativity compared to neutral pictures. Of main interest, increasing demands of the auditory task did not modulate the selective processing of emotional visual stimuli. With regard to the locus of interference, selective emotion processing as indexed by the EPN does not seem to reflect shared processing resources of visual and auditory modality.
Saturday, July 26, 2008
ARTICLE UPDATE - Neural processing of vocal emotion and identity.
Spreckelmeyer KN, Kutas M, Urbach T, Altenmüller E, Münte TF.
Brain & Cognition, in press
The voice is a marker of a person's identity which allows individual recognition even if the person is not in sight. Listening to a voice also affords inferences about the speaker's emotional state. Both these types of personal information are encoded in characteristic acoustic feature patterns analyzed within the auditory cortex. In the present study 16 volunteers listened to pairs of non-verbal voice stimuli with happy or sad valence in two different task conditions while event-related brain potentials (ERPs) were recorded. In an emotion matching task, participants indicated whether the expressed emotion of a target voice was congruent or incongruent with that of a (preceding) prime voice. In an identity matching task, participants indicated whether or not the prime and target voice belonged to the same person. Effects based on emotion expressed occurred earlier than those based on voice identity. Specifically, P2 ( approximately 200ms)-amplitudes were reduced for happy voices when primed by happy voices. Identity match effects, by contrast, did not start until around 300ms. These results show an early task-specific emotion-based influence on the early stages of auditory sensory processing.
Brain & Cognition, in press
The voice is a marker of a person's identity which allows individual recognition even if the person is not in sight. Listening to a voice also affords inferences about the speaker's emotional state. Both these types of personal information are encoded in characteristic acoustic feature patterns analyzed within the auditory cortex. In the present study 16 volunteers listened to pairs of non-verbal voice stimuli with happy or sad valence in two different task conditions while event-related brain potentials (ERPs) were recorded. In an emotion matching task, participants indicated whether the expressed emotion of a target voice was congruent or incongruent with that of a (preceding) prime voice. In an identity matching task, participants indicated whether or not the prime and target voice belonged to the same person. Effects based on emotion expressed occurred earlier than those based on voice identity. Specifically, P2 ( approximately 200ms)-amplitudes were reduced for happy voices when primed by happy voices. Identity match effects, by contrast, did not start until around 300ms. These results show an early task-specific emotion-based influence on the early stages of auditory sensory processing.
Friday, July 18, 2008
ARTICLE UPDATE - Emotional states influence the neural processing of affective language.
Pratt NL, Kelly SD.
Social Neuroscience, 3, 1-9
The present study investigated whether emotional states influence the neural processing of language. Event-related potentials recorded the brain's response to positively and negatively valenced words (e.g., love vs. death) while participants were directly induced into positive and negative moods. ERP electrodes in frontal scalp regions of the brain distinguished positive and negative words around 400 ms poststimulus. The amplitude of this negative waveform showed a larger negativity for positive words compared to negative words in the frontal electrode region when participants were in a positive, but not negative, mood. These findings build on previous research by demonstrating that people process affective language differently when in positive and negative moods, and lend support to recent views that emotion and cognition interact during language comprehension.
Social Neuroscience, 3, 1-9
The present study investigated whether emotional states influence the neural processing of language. Event-related potentials recorded the brain's response to positively and negatively valenced words (e.g., love vs. death) while participants were directly induced into positive and negative moods. ERP electrodes in frontal scalp regions of the brain distinguished positive and negative words around 400 ms poststimulus. The amplitude of this negative waveform showed a larger negativity for positive words compared to negative words in the frontal electrode region when participants were in a positive, but not negative, mood. These findings build on previous research by demonstrating that people process affective language differently when in positive and negative moods, and lend support to recent views that emotion and cognition interact during language comprehension.
ARTICLE UPDATE - Asymmetrical frontal ERPs, emotion, and behavioral approach/inhibition sensitivity.
Peterson CK, Gable P, Harmon-Jones E.
Social Neuroscience, 113-124
The present study sought to extend past research on frontal brain asymmetry and individual differences by examining relationships of individual differences in behavioral inhibition/approach system (BIS/BAS) sensitivity with asymmetrical frontal event-related brain responses to startle probes presented during viewing of affective pictures. One hundred and ten participants were shown unpleasant, neutral, and pleasant affective pictures, and presented startle probes during picture presentations. Individual differences in BIS sensitivity related to relatively greater right frontal N100 amplitude to startle probes presented during pleasant and unpleasant pictures, whereas individual differences in BAS sensitivity related to reduced left frontal P300 amplitude to startle probes presented during pleasant pictures. The results of this study suggest that BIS sensitivity is related to greater relative right frontal cortical activity during affective states, while BAS sensitivity is related to greater relative left frontal cortical activity during appetitive states.
Social Neuroscience, 113-124
The present study sought to extend past research on frontal brain asymmetry and individual differences by examining relationships of individual differences in behavioral inhibition/approach system (BIS/BAS) sensitivity with asymmetrical frontal event-related brain responses to startle probes presented during viewing of affective pictures. One hundred and ten participants were shown unpleasant, neutral, and pleasant affective pictures, and presented startle probes during picture presentations. Individual differences in BIS sensitivity related to relatively greater right frontal N100 amplitude to startle probes presented during pleasant and unpleasant pictures, whereas individual differences in BAS sensitivity related to reduced left frontal P300 amplitude to startle probes presented during pleasant pictures. The results of this study suggest that BIS sensitivity is related to greater relative right frontal cortical activity during affective states, while BAS sensitivity is related to greater relative left frontal cortical activity during appetitive states.
Friday, May 09, 2008
ARTICLE UPDATE - Early emotion word processing: Evidence from event-related potentials.
Scott GG, O'Donnell PJ, Leuthold H, Sereno SC.
Biological Psychology, in press
Behavioral and electrophysiological responses were monitored to 80 controlled sets of emotionally positive, negative, and neutral words presented randomly in a lexical decision paradigm. Half of the words were low frequency and half were high frequency. Behavioral results showed significant effects of frequency and emotion as well as an interaction. Prior research has demonstrated sensitivity to lexical processing in the N1 component of the event-related brain potential (ERP). In this study, the N1 (135-180ms) showed a significant emotion by frequency interaction. The P1 window (80-120ms) preceding the N1 as well as post-N1 time windows, including the Early Posterior Negativity (200-300ms) and P300 (300-450ms), were examined. The ERP data suggest an early identification of the emotional tone of words leading to differential processing. Specifically, high frequency negative words seem to attract additional cognitive resources. The overall pattern of results is consistent with a time line of word recognition in which semantic analysis, including the evaluation of emotional quality, occurs at an early, lexical stage of processing.
Biological Psychology, in press
Behavioral and electrophysiological responses were monitored to 80 controlled sets of emotionally positive, negative, and neutral words presented randomly in a lexical decision paradigm. Half of the words were low frequency and half were high frequency. Behavioral results showed significant effects of frequency and emotion as well as an interaction. Prior research has demonstrated sensitivity to lexical processing in the N1 component of the event-related brain potential (ERP). In this study, the N1 (135-180ms) showed a significant emotion by frequency interaction. The P1 window (80-120ms) preceding the N1 as well as post-N1 time windows, including the Early Posterior Negativity (200-300ms) and P300 (300-450ms), were examined. The ERP data suggest an early identification of the emotional tone of words leading to differential processing. Specifically, high frequency negative words seem to attract additional cognitive resources. The overall pattern of results is consistent with a time line of word recognition in which semantic analysis, including the evaluation of emotional quality, occurs at an early, lexical stage of processing.
Friday, March 14, 2008
ARTICLE UPDATE - Distinct effects of attention and affect on pain perception and somatosensory evoked potentials.
Kenntner-Mabiala R, Andreatta M, Wieser MJ, Mühlberger A, Pauli P.
Biological Psychology, in press
The influence of affect and attention on sensory and affective pain as well as on somatosensory evoked potentials in response to painful and nonpainful electrical stimuli was investigated in a single experimental design. Affect was induced by pictures from the International Affective Picture System; attention was manipulated by asking participants to focus attention either on the pictures or on the electrical stimuli. Sensory and affective pain ratings were generally lower during exposure to positive compared to negative and neutral pictures. Attention modulated only sensory pain ratings with lower ratings with an attention focus on pictures than with an attention focus on sensory pain. The N150 was modulated by picture valence, the P260 by picture arousal. Furthermore, the P260 was modulated by attention with highest amplitudes with an attention focus on the stimulus intensity. This study provides neurophysiological evidence that attention and affect have distinct effects on pain processing.
Biological Psychology, in press
The influence of affect and attention on sensory and affective pain as well as on somatosensory evoked potentials in response to painful and nonpainful electrical stimuli was investigated in a single experimental design. Affect was induced by pictures from the International Affective Picture System; attention was manipulated by asking participants to focus attention either on the pictures or on the electrical stimuli. Sensory and affective pain ratings were generally lower during exposure to positive compared to negative and neutral pictures. Attention modulated only sensory pain ratings with lower ratings with an attention focus on pictures than with an attention focus on sensory pain. The N150 was modulated by picture valence, the P260 by picture arousal. Furthermore, the P260 was modulated by attention with highest amplitudes with an attention focus on the stimulus intensity. This study provides neurophysiological evidence that attention and affect have distinct effects on pain processing.
ARTICLE UPDATE - Affective Prime and Target Picture Processing: An ERP Analysis of Early and Late Interference Effects.
Flaisch T, Stockburger J, Schupp HT.
Brain Topography, in press
Viewing emotionally arousing compared to neutral pictures is associated with differential electrophysiological activity in early ("early posterior negativity", EPN), as well as later time-windows ("late positive potential", LPP). A previous study revealed that the EPN is reduced when the preceding prime picture was emotional. The present study explored whether sequential interference effects are specific for early processing stages or extend to later processing stages. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 660 ms each. Previous results were replicated in that emotional pictures were associated with enlarged EPN and LPP amplitudes compared to neutral pictures. Furthermore, the EPN to emotional and neutral pictures was reduced when preceded by pleasant prime pictures. The novel finding was that emotional compared to neutral prime pictures were associated with reduced LPP amplitudes to the subsequently presented picture irrespective of its emotional valence (pleasant, neutral, unpleasant). These results demonstrate sustained interference effects in serial picture presentations discussed within a framework of resource competition among successive pictures.
Brain Topography, in press
Viewing emotionally arousing compared to neutral pictures is associated with differential electrophysiological activity in early ("early posterior negativity", EPN), as well as later time-windows ("late positive potential", LPP). A previous study revealed that the EPN is reduced when the preceding prime picture was emotional. The present study explored whether sequential interference effects are specific for early processing stages or extend to later processing stages. Dense sensor ERPs were measured while subjects viewed a continuous stream of pleasant, neutral, and unpleasant pictures, presented for 660 ms each. Previous results were replicated in that emotional pictures were associated with enlarged EPN and LPP amplitudes compared to neutral pictures. Furthermore, the EPN to emotional and neutral pictures was reduced when preceded by pleasant prime pictures. The novel finding was that emotional compared to neutral prime pictures were associated with reduced LPP amplitudes to the subsequently presented picture irrespective of its emotional valence (pleasant, neutral, unpleasant). These results demonstrate sustained interference effects in serial picture presentations discussed within a framework of resource competition among successive pictures.
Friday, February 29, 2008
ARTICLE UPDATE - Differential effects of object-based attention on evoked potentials to fearful and disgusted faces.
Isabel M. Santos, Jaime Iglesias, Ela I. Olivares and Andrew W. Young
Neuropsychologia, in press
Event-related potentials (ERPs) were used to investigate the role of attention on the processing of facial expressions of fear and disgust. Stimuli consisted of overlapping pictures of a face and a house. Participants had to monitor repetitions of faces or houses, in separate blocks of trials, so that object-based attention was manipulated while spatial attention was kept constant. Faces varied in expression and could be either fearful or neutral (in the fear condition) or disgusted or neutral (in the disgust condition). When attending to faces, participants were required to signal repetitions of the same person, with the facial expressions being completely irrelevant to the task. Different effects of selective attention and different patterns of brain activity were observed for faces with fear and disgust expressions. Results indicated that the perception of fear from faces is gated by selective attention at early latencies, whereas a sustained positivity for fearful faces compared to neutral faces emerged around 160ms at central-parietal sites, independent of selective attention. In the case of disgust, ERP differences began only around 160ms after stimulus onset, and only after 480ms was the perception of disgust modulated by attention allocation. Results are interpreted in terms of different neural mechanisms for the perception of fear and disgust and related to the functional significance of these two emotions for the survival of the organism.
Neuropsychologia, in press
Event-related potentials (ERPs) were used to investigate the role of attention on the processing of facial expressions of fear and disgust. Stimuli consisted of overlapping pictures of a face and a house. Participants had to monitor repetitions of faces or houses, in separate blocks of trials, so that object-based attention was manipulated while spatial attention was kept constant. Faces varied in expression and could be either fearful or neutral (in the fear condition) or disgusted or neutral (in the disgust condition). When attending to faces, participants were required to signal repetitions of the same person, with the facial expressions being completely irrelevant to the task. Different effects of selective attention and different patterns of brain activity were observed for faces with fear and disgust expressions. Results indicated that the perception of fear from faces is gated by selective attention at early latencies, whereas a sustained positivity for fearful faces compared to neutral faces emerged around 160ms at central-parietal sites, independent of selective attention. In the case of disgust, ERP differences began only around 160ms after stimulus onset, and only after 480ms was the perception of disgust modulated by attention allocation. Results are interpreted in terms of different neural mechanisms for the perception of fear and disgust and related to the functional significance of these two emotions for the survival of the organism.
Tuesday, February 05, 2008
ARTICLE UPDATE - The cognitive consequences of emotion regulation: An ERP investigation.
Deveney CM, Pizzagalli DA.
Psychophysiology, in press
Increasing evidence suggests that emotion regulation (ER) strategies modulate encoding of information presented during regulation; however, no studies have assessed the impact of cognitive reappraisal ER strategies on the processing of stimuli presented after the ER period. Participants in the present study regulated emotions to unpleasant pictures and then judged whether a word was negative or neutral. Electromyographic measures (corrugator supercilli) confirmed that individuals increased and decreased negative affect according to ER condition. Event-related potential analyses revealed smallest N400 amplitudes to negative and neutral words presented after decreasing unpleasant emotions and smallest P300 amplitudes to words presented after increasing unpleasant emotions whereas reaction time data failed to show ER modulations. Results are discussed in the context of the developing ER literature, as well as theories of emotional incongruity (N400) and resource allocation (P300).
Psychophysiology, in press
Increasing evidence suggests that emotion regulation (ER) strategies modulate encoding of information presented during regulation; however, no studies have assessed the impact of cognitive reappraisal ER strategies on the processing of stimuli presented after the ER period. Participants in the present study regulated emotions to unpleasant pictures and then judged whether a word was negative or neutral. Electromyographic measures (corrugator supercilli) confirmed that individuals increased and decreased negative affect according to ER condition. Event-related potential analyses revealed smallest N400 amplitudes to negative and neutral words presented after decreasing unpleasant emotions and smallest P300 amplitudes to words presented after increasing unpleasant emotions whereas reaction time data failed to show ER modulations. Results are discussed in the context of the developing ER literature, as well as theories of emotional incongruity (N400) and resource allocation (P300).
Monday, January 14, 2008
ARTICLE UPDATE - An ERP investigation on the temporal dynamics of emotional prosody and emotional semantics in pseudo- and lexical-sentence context.
Paulmann S, Kotz SA.
Brain and Language, in press
Previous evidence supports differential event-related brain potential (ERP) responses for emotional prosodic processing and integrative emotional prosodic/semantic processing. While latter process elicits a negativity similar to the well-known N400 component, transitions in emotional prosodic processing elicit a positivity. To further substantiate this evidence, the current investigation utilized lexical-sentences and sentences without lexical content (pseudo-sentences) spoken in six basic emotions by a female and a male speaker. Results indicate that emotional prosodic expectancy violations elicit a right-lateralized positive-going ERP component independent of basic emotional prosodies and speaker voice. In addition, expectancy violations of integrative emotional prosody/semantics elicit a negativity with a whole-head distribution. The current results nicely complement previous evidence, and extend the results by showing the respective effects for a wider range of emotional prosodies independent of lexical content and speaker voice.
Brain and Language, in press
Previous evidence supports differential event-related brain potential (ERP) responses for emotional prosodic processing and integrative emotional prosodic/semantic processing. While latter process elicits a negativity similar to the well-known N400 component, transitions in emotional prosodic processing elicit a positivity. To further substantiate this evidence, the current investigation utilized lexical-sentences and sentences without lexical content (pseudo-sentences) spoken in six basic emotions by a female and a male speaker. Results indicate that emotional prosodic expectancy violations elicit a right-lateralized positive-going ERP component independent of basic emotional prosodies and speaker voice. In addition, expectancy violations of integrative emotional prosody/semantics elicit a negativity with a whole-head distribution. The current results nicely complement previous evidence, and extend the results by showing the respective effects for a wider range of emotional prosodies independent of lexical content and speaker voice.
ARTICLE UPDATE -Visual noise effects on emotion perception: brain potentials and stimulus identification.
Schupp HT, Stockburger J, Schmälzle R, Bublatzky F, Weike AI, Hamm AO.
Neuroreport, 19, 167-171
Event-related potential (ERP) studies revealed an early posterior negativity (EPN) for emotionally arousing pictures. Two studies explored how this effect relates to perceptual stimulus characteristics and stimulus identification. Adding various amounts of visual noise varied stimulus perceptibility of high and low arousing picture contents, which were presented as rapid and continuous stream. Measuring dense sensor event-related potentials, study I determined that noise level was linearly related to the P1 peak. Subsequently, enlarged EPNs to emotionally arousing contents were observed, however, only for pictures containing low amounts of noise, which also enabled stimulus identification as shown by study II. These data support the notion that the EPN may serve as a measure of affective stimulus evaluation at an early transitory processing period.
Neuroreport, 19, 167-171
Event-related potential (ERP) studies revealed an early posterior negativity (EPN) for emotionally arousing pictures. Two studies explored how this effect relates to perceptual stimulus characteristics and stimulus identification. Adding various amounts of visual noise varied stimulus perceptibility of high and low arousing picture contents, which were presented as rapid and continuous stream. Measuring dense sensor event-related potentials, study I determined that noise level was linearly related to the P1 peak. Subsequently, enlarged EPNs to emotionally arousing contents were observed, however, only for pictures containing low amounts of noise, which also enabled stimulus identification as shown by study II. These data support the notion that the EPN may serve as a measure of affective stimulus evaluation at an early transitory processing period.
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