Changes in emotional tone and instrumental timbre are reflected by the mismatch negativity

The present study examined whether or not the brain is capable to preattentively discriminate tones differing in emotional expression or instrumental timbre. In two event-related potential (ERP) experiments single tones (600 ms) were presented which had been rated as happy or sad in a pretest. In experiment 1, 12 non-musicians passively listened to tone series comprising a frequent (standard) single musical tone played by a violin in a certain pitch and with a certain emotional connotation (happy or sad). Among these standard tones deviant tones differing in emotional valence, either in instrumental timbre or in pitch were presented. All deviants generated mismatch negativity (MMN) responses. The MMN scalp topography was similar for all of the three deviants but latency was shorter for pitch deviants than for the other two conditions. The topography of the mismatch responses was indistinguishable. In a second experiment, subjects actively detected the deviant tones by button press. All detected deviants generated P3b waves at parietal leads. These results indicate that the brain is not only able to use simple physical differences such as pitch for rapid preattentive categorization but can also perform similar operations on the basis of more complex differences between tones of the same pitch such as instrumental timbre and the subtle timbral differences associated with different emotional expression. This rapid categorization may serve as a basis for the further fine-grained analysis of musical (and other) sounds with regard to their emotional content.     

An ERP study of vocal emotion processing in asymmetric Parkinson’s disease

Parkinson’s disease (PD) has been related to impaired processing of emotional speech intonation (emotional prosody). One distinctive feature of idiopathic PD is motor symptom asymmetry, with striatal dysfunction being strongest in the hemisphere contralateral to the most affected body side. It is still unclear whether this asymmetry may affect vocal emotion perception. Here, we tested 22 PD patients (10 with predominantly left-sided [LPD] and 12 with predominantly right-sided motor symptoms) and 22 healthy controls in an event-related potential study. Sentences conveying different emotional intonations were presented in lexical and pseudo-speech versions. Task varied between an explicit and an implicit instruction. Of specific interest was emotional salience detection from prosody, reflected in the P200 component. We predicted that patients with predominantly right-striatal dysfunction (LPD) would exhibit P200 alterations. Our results support this assumption. LPD patients showed enhanced P200 amplitudes, and specific deficits were observed for disgust prosody, explicit anger processing and implicit processing of happy prosody. Lexical speech was predominantly affected while the processing of pseudo-speech was largely intact. P200 amplitude in patients correlated significantly with left motor scores and asymmetry indices. The data suggest that emotional salience detection from prosody is affected by asymmetric neuronal degeneration in PD.     

Optimizing the auditory distraction paradigm: behavioral and event-related potential effects in a lateralized multi-deviant approach.

OBJECTIVE: The present study aimed at adapting a multi-deviant auditory distraction paradigm for a comprehensive screening of functions of voluntary and involuntary auditory attention. METHODS: Subjects performed phonetic discrimination on lateralized consonant-vowel syllables in a distraction paradigm in which task-irrelevant deviances occurred on different syllable features. Behavioral performance and event-related potentials (ERPs) were measured within a multi-deviant (frequency, location, and duration deviants, p=0.11 each) and a classic single-deviant design (frequency deviants only, p=0.11). Additionally, ERP effects obtained in an active and a passive multi-deviant condition were compared. RESULTS: Behavioral and electrophysiological deviance-related effects were rather similar in the multi-deviant and the single-deviant paradigm. Furthermore, the comparison to the passive listening condition revealed a marked effect of voluntary attention on sensory processing of the syllables. CONCLUSIONS: The multi-deviant distraction paradigm provides a gain in time compared to the classic single-deviant distraction paradigm which is not accompanied by a loss in the strength of the effects. Inclusion of a passive listening condition enables the additional evaluation of effects of voluntary attention. SIGNIFICANCE: The present multi-deviant distraction paradigm creates an important step towards a tool suited to investigate involuntary and voluntary attention in selected groups of patients during the processing of task-relevant and task-irrelevant auditory information across different acoustic dimensions.     

The neural response to emotional prosody,as revealed by functional magnetic resonance imaging

Prosody is an important feature of language, comprising intonation, loudness, and tempo. Emotional prosodic processing forms an integral part of our social interactions. The main aim of this study was to use bold contrast fMRI to clarify the normal functional neuroanatomy of emotional prosody, in passive and active contexts. Subjects performed six separate scanning studies, within which two different conditions were contrasted: (1) "pure" emotional prosody versus rest; (2) congruent emotional prosody versus 'neutral' sentences; (3) congruent emotional prosody versus rest; (4) incongruent emotional prosody versus rest; (5) congruent versus incongruent emotional prosody; and (6) an active experiment in which subjects were instructed to either attend to the emotion conveyed by semantic content or that conveyed by tone of voice. Data resulting from these contrasts were analysed using SPM99. Passive listening to emotional prosody consistently activated the lateral temporal lobe (superior and/or middle temporal gyri). This temporal lobe response was relatively right-lateralised with or without semantic information. Both the separate and direct comparisons of congruent and incongruent emotional prosody revealed that subjects used fewer brain regions to process incongruent emotional prosody than congruent. The neural response to attention to semantics, was left lateralised, and recruited an extensive network not activated by attention to emotional prosody. Attention to emotional prosody modulated the response to speech, and induced right-lateralised activity, including the middle temporal gyrus. In confirming the results of lesion and neuropsychological studies, the current study emphasises the importance of the right hemisphere in the processing of emotional prosody, specifically the lateral temporal lobes.     

Brain oscillatory patterns of affective prosody perception in children with autism spectrum disorder

BackgroundParalinguistic features, such as prosody (tempo, loudness, and timbre), are an essential marker of a speaker’s emotional state. Abnormal processing of emotional prosody may result in the deficient social behavior associated with autism spectrum disorder (ASD).MethodTwo groups of children participated in our study: the ASD group consisted of 30 preschoolers from 4 to 6 years of age and 24 typically developing (TD) peers. An electroencephalogram (EEG) was acquired in response to a combination of syllables uttered with the following types of emotional prosody: joy, anger, sadness, fear, and calmness.ResultsChildren with ASD and TD showed a similar EEG oscillatory response to fear and anger prosodies. Significant group differences in power spectral density (PSD) were detected for sad and joy intonations. The PSD differences between pairs of intonations, such as joyful and sad, sad and neutral, or joyful and neutral, were significantly higher in the control group than in the ASD group. EEG responses to affective prosody also demonstrated less hemispheric asymmetry in the ASD than in the TD group.ConclusionsOur results suggest that difficulties in emotional prosody recognition in autistic children could be based on the atypical processing of specific acoustic features coding differences between sad, neutral, and joyful intonations and could underlie emotional perception deficits in individuals with ASD.     

On the role of attention for the processing of emotions in speech: sex differences revisited

In a previous cross-modal priming study [A. Schirmer, A.S. Kotz, A.D. Friederici, Sex differentiates the role of emotional prosody during word processing, Cogn. Brain Res. 14 (2002) 228-233.], we found that women integrated emotional prosody and word valence earlier than men. Both sexes showed a smaller N400 in the event-related potential to emotional words when these words were preceded by a sentence with congruous compared to incongruous emotional prosody. However, women showed this effect with a 200-ms interval between prime sentence and target word whereas men showed the effect with a 750-ms interval. The present study was designed to determine whether these sex differences prevail when attention is directed towards the emotional content of prosody and word meaning. To this end, we presented the same prime sentences and target words as in our previous study. Sentences were spoken with happy or sad prosody and followed by a congruous or incongruous emotional word or pseudoword. The interval between sentence offset and target onset was 200 ms. In addition to performing a lexical decision, participants were asked to decide whether or not a word matched the emotional prosody of the preceding sentence. The combined lexical and congruence judgment failed to reveal differences in emotional-prosodic priming between men and women. Both sexes showed smaller N400 amplitudes to emotionally congruent compared to incongruent words. This suggests that the presence of sex differences in emotional-prosodic priming depends on whether or not participants are instructed to take emotional prosody into account.     

Abnormal emotional word ratings in Parkinson's disease

Blunted facial expressions and diminished expressions of emotional prosody associated with Parkinson's disease (PD) could be attributed to motor rigidity/akinesia. Although impaired recognition of emotional faces and prosody in PD suggests emotional dysfunction is not entirely motor-efferent, comprehension might depend upon imitation with motor feedback. Thus, to learn if patients with PD have an emotional conceptual defect, we examined their ratings for the emotional connotations of words on a 1-9 scale for valence and arousal. When compared to control participants the valence (positive-negative) and arousal (excited-calm) ratings of the PD patients were blunted, but their ratings of the control expense words (expensive-cheap) were not. These blunted emotion ratings suggest that patients with PD have a degradation of their emotional conceptual-semantic system.     

Emotional speech in Parkinson's disease

Patients with Parkinson's disease (PD) tend to speak monotonously with minor modulation of pitch and intensity. The goal of this study was to find out whether these speech changes can be explained mainly by motor impairment, i.e. akinesia and rigidity of the articulatory apparatus, or whether alterations of emotional processing play an additional role. Sixteen patients with mild PD and 16 healthy controls (HC) were compared. Fundamental frequencies (pitch) and intensities (loudness) were determined as (1) maximal upper and lower values achieved in nonemotional speech (phonation capacity), (2) upper and lower values used when speaking “Anna” in emotional intonation (neutral, sad, happy) as requested (production task), or (3) when imitating a professional speaker (imitation task). Although groups did not significantly differ in their phonation capacity, patients showed a significantly smaller pitch and intensity range than HC in the production task. In the imitation task, however, ranges were again similar. These results suggest that alterations of emotional processing contribute to speech changes in PD, especially regarding emotional prosody, in addition to motor impairment. © 2008 Movement Disorder Society     

Recognition of emotions from visual and prosodic cues in Parkinson’s disease

OBJECTIVE: To assess whether Parkinson Disease (PD) patients are impaired at perceiving emotions from facial and prosodic cues and whether any putative defective performance concerns recognition of a particular emotion. BACKGROUND: Braak et al. [1] demonstrated that in different stages PD pathology involves the nigrostriatal system, the amygdala, and the insular cortex. Discrete brain lesions to these structures can cause selective deficits in recognising facial and prosodic stimuli expressing particular emotions. However, the investigation of facial and prosodic emotional processing in PD patients has lead to conflicting results. MATERIALS AND METHODS: We compared 27 cognitively unimpaired PD patients with control subjects by means of the Facial Emotion Recognition Battery and the Emotional Prosody Recognition Battery. RESULTS: PD patients were impaired in recognising, selecting, and matching facial affects. In particular, the Facial Emotion Recognition Battery demonstrated a severe impairment in recognising sad and fearful faces. In the Emotional Prosody Recognition Battery PD patients demonstrated a diffuse impairment, including the recognition of emotional and propositional prosody. CONCLUSIONS: Face emotion processing is impaired in PD patients, with a disproportionate deficit involving fear and sadness. The pattern of face expression processing impairment in PD patients might depend on the regional distribution of the pathology. The widespread involvement of both emotional and propositional prosodic processing parallels the aprosodic characteristics of Parkinsonian speech production.     

Deficient recognition of emotional prosody in primary focal dystonia

Background: Primary dystonia is a movement disorder attributed mainly to basal ganglia dysfunction. Besides motor control, striatopallidal structures are known to implement also non‐motor functions including processing of cognitive and emotional information. Previous research has already demonstrated deficient recognition of emotional faces in patients with primary focal dystonia. However, it remains elusive if emotional prosody processing in dystonia is also affected. Methods: In this study, 30 patients with primary cervical dystonia (CD) and 30 healthy control subjects (HC) had to classify auditory presented words according to their emotional prosody (angry, happy, relaxed, sad). Results: Analysis of hit rates and reaction times revealed a significantly poorer performance of patients with CD in judging angrily intonated words. Additional psychological assessment (SCL‐90 R) demonstrated a higher level of psychological distress in patients with CD who displayed symptoms of somatization, anxiety and depression. Conclusions: Together these findings bring further insight into the basal ganglia involvement in processing of emotional prosody and emphasize the importance to identify the psychopathological symptoms in patients with CD as complementary to the motor deficit.     

Emotion processing in Parkinson's disease: dissociation between early neuronal processing and explicit ratings.

OBJECTIVE: Patients suffering from Parkinson's disease (PD) have a diminished ability to discriminate facial expressions of emotion. We investigated early emotion discrimination deficits in PD by means of event-related potentials (ERPs). METHODS: Emotional pictures were presented to 14 PD patients and 14 healthy controls in a rapid serial visual presentation paradigm (three frames per second) while EEG was recorded. In addition, valence and arousal ratings were obtained for a representative subsample of 54 pictures. RESULTS: PD patients rated pictures of highly arousing content as less exciting than did healthy controls. Pictures of high compared to low emotional arousal were associated with a pronounced relative negative shift in the ERP waveform over parietal and occipital sites developing about 220 ms after picture onset. This early posterior negativity (EPN) did not differ between PD and control group. CONCLUSIONS: This dissociation of affective ratings and early ERP components supports the view that PD is associated with blunted emotional responses, but there is no evidence for a deteriorated early visual processing of emotional stimuli. SIGNIFICANCE: Frequently reported deficits in emotion discrimination are likely not due to deficits in early emotion processing.     

Advanced Parkinson disease patients have impairment in prosody processing

Background: The ability to recognize and interpret emotions in others is a crucial prerequisite of adequate social behavior. Impairments in emotion processing have been reported from the early stages of Parkinson’s disease (PD). This study aims to characterize emotion recognition in advanced Parkinson’s disease (APD) candidates for deep-brain stimulation and to compare emotion recognition abilities in visual and auditory domains. Method: APD patients, defined as those with levodopa-induced motor complications (N = 42), and healthy controls (N = 43) matched by gender, age, and educational level, undertook the Comprehensive Affect Testing System (CATS), a battery that evaluates recognition of seven basic emotions (happiness, sadness, anger, fear, surprise, disgust, and neutral) on facial expressions and four emotions on prosody (happiness, sadness, anger, and fear). APD patients were assessed during the “ON” state. Group performance was compared with independent-samples t tests. Results: Compared to controls, APD had significantly lower scores on the discrimination and naming of emotions in prosody, and visual discrimination of neutral faces, but no significant differences in visual emotional tasks. Conclusion: The contrasting performance in emotional processing between visual and auditory stimuli suggests that APD candidates for surgery have either a selective difficulty in recognizing emotions in prosody or a general defect in prosody processing. Studies investigating early-stage PD, and the effect of subcortical lesions in prosody processing, favor the latter interpretation. Further research is needed to understand these deficits in emotional prosody recognition and their possible contribution to later behavioral or neuropsychiatric manifestations of PD.     

Sex differences in brain control of prosody

Affective (emotional) prosody is a neuropsychological function that encompasses non-verbal aspects of language that are necessary for recognizing and conveying emotions in communication, whereas non-affective (linguistic) prosody indicates whether the sentence is a question, an order or a statement. Considerable evidence points to a dominant role for the right hemisphere in both aspects of prosodic function. However, it has yet to be established whether separate parts of the right hemisphere are involved in processing different kinds of emotional intonation. The aim of this study was to answer this question. In addition, the issue of sex differences in the ability to understand prosody was considered. Fifty-two patients with damage to frontal, temporo-parietal or subcortical (basal) parts of the right hemisphere and 26 controls were tested for their ability to assess prosody information in normal (well-formed) sentences and in pseudo-sentences. General impairment of prosody processing was seen in all patient groups but the effect of damage was more apparent for emotional rather than linguistic prosody. Interestingly, appreciation of emotional prosody appeared to depend on the type of emotional expression and the location of the brain lesion. The patients with frontal damage were mostly impaired in comprehension of happy intonations; those with temporo-parietal damage in assessment of sad intonations, while subcortical lesions mostly affected comprehension of angry intonations. Differential effects of lesion location on the performance of men and women were also observed. Frontal lesions were more detrimental to women, whereas subcortical lesions led to stronger impairment in men. This suggests sex differences in brain organization of prosodic functions.     

Recognition of emotional prosody is altered after subthalamic nucleus deep brain stimulation in Parkinson's disease

The recognition of facial emotions is impaired following subthalamic nucleus (STN) deep brain stimulation (DBS) in Parkinson's disease (PD). These changes have been linked to a disturbance in the STN's limbic territory, which is thought to be involved in emotional processing. This was confirmed by a recent PET study where these emotional modifications were correlated with changes in glucose metabolism in different brain regions, including the amygdala and the orbitofrontal regions that are well known for their involvement in emotional processing. Nevertheless, the question as to whether these emotional changes induced by STN DBS in PD are modality-specific has yet to be answered. The objective of this study was therefore to examine the effects of STN DBS in PD on the recognition of emotional prosody.An original emotional prosody paradigm was administered to twenty-one post-operative PD patients, twenty-one pre-operative PD patients and twenty-one matched controls. Results showed that both the pre- and post-operative groups differed from the healthy controls. There was also a significant difference between the pre and post groups. More specifically, an analysis of their continuous judgments revealed that the performance of the post-operative group compared with that of the other two groups was characterized by a systematic emotional bias whereby they perceived emotions more strongly.These results suggest that the impaired recognition of emotions may not be specific to the visual modality but may also be present when emotions are expressed through the human voice, implying the involvement of the STN in the brain network underlying the recognition of emotional prosody.     

Major depressive disorder skews the recognition of emotional prosody

Objective

Major depressive disorder (MDD) is associated with abnormalities in the recognition of emotional stimuli. MDD patients ascribe more negative emotion but also less positive emotion to facial expressions, suggesting blunted responsiveness to positive emotional stimuli. To ascertain whether these emotional biases are modality-specific, we examined the effects of MDD on the recognition of emotions from voices using a paradigm designed to capture subtle effects of biases.

Methods

Twenty-one MDD patients and 21 healthy controls (HC) underwent clinical and neuropsychological assessments, followed by a paradigm featuring pseudowords spoken by actors in five types of emotional prosody, rated on continuous scales.

Results

Overall, MDD patients performed more poorly than HC, displaying significantly impaired recognition of fear, happiness and sadness. Compared with HC, they rated fear significantly more highly when listening to anger stimuli. They also displayed a bias toward surprise, rating it far higher when they heard sad or fearful utterances. Furthermore, for happiness stimuli, MDD patients gave higher ratings for negative emotions (fear and sadness). A multiple regression model on recognition of emotional prosody in MDD patients showed that the best fit was achieved using the executive functioning (categorical fluency, number of errors in the MCST, and TMT B-A) and the total score of the Montgomery-Asberg Depression Rating Scale.

Conclusions

Impaired recognition of emotions would appear not to be specific to the visual modality but to be present also when emotions are expressed vocally, this impairment being related to depression severity and dysexecutive syndrome. MDD seems to skew the recognition of emotional prosody toward negative emotional stimuli and the blunting of positive emotion appears not to be restricted to the visual modality.     

ERP indices of resource allocation difficulties in mild head injury

This study examined the hypothesis that distractibility is a characteristic sequela of mild closed head injury (MHI). The Minnesota Multiphasic Personality Inventory (MMPI-2) was used to study whether comorbid stress-related symptoms are associated with behavioral and electrophysiological indexes of attention. Event-related potentials (ERPs) and performance (reaction time, accuracy) were studied in patients with MHI (n = 20), patients with frontal lesions (n = 14), and healthy controls (n = 20) during a three-tone oddball task. Participants were instructed to detect rare target (2000 Hz) tones, and to withhold responding to equally rare distractor (500 Hz) tones and frequently occurring standard (1000 Hz) tones. All groups distinguished the two classes of deviants as indicated by the larger P3 amplitude to target relative to distractor tones. This indicates that the group with MHI was capable of differential allocation of attentional resources to target and non-target events. However, impaired performance and attenuated ERP amplitudes to both classes of deviants relative to patients with frontal lesions and controls, suggest limited availability, or expenditure of the resources needed for adequate task performance. In the group with MHI, both P3 amplitude and reaction time (RT) were significantly related to subjectively reported distress. The difference in RT disappeared, whereas the P3 amplitude differences between the patient groups remained when adjusting for level of distress.     

ERP Indices of Resource Allocation Difficulties in Mild Head Injury

This study examined the hypothesis that distractibility is a characteristic sequela of mild closed head injury (MHI). The Minnesota Multiphasic Personality Inventory (MMPI-2) was used to study whether comorbid stress-related symptoms are associated with behavioral and electrophysiological indexes of attention. Event-related potentials (ERPs) and performance (reaction time, accuracy) were studied in patients with MHI (n = 20), patients with frontal lesions (n = 14), and healthy controls (n = 20) during a three-tone oddball task. Participants were instructed to detect rare target (2000 Hz) tones, and to withhold responding to equally rare distractor (500 Hz) tones and frequently occurring standard (1000 Hz) tones. All groups distinguished the two classes of deviants as indicated by the larger P3 amplitude to target relative to distractor tones. This indicates that the group with MHI was capable of differential allocation of attentional resources to target and non-target events. However, impaired performance and attenuated ERP amplitudes to both classes of deviants relative to patients with frontal lesions and controls, suggest limited availability, or expenditure of the resources needed for adequate task performance. In the group with MHI, both P3 amplitude and reaction time (RT) were significantly related to subjectively reported distress. The difference in RT disappeared, whereas the P3 amplitude differences between the patient groups remained when adjusting for level of distress.     

Emotional perception deficits in amyotrophic lateral sclerosis.

OBJECTIVE: Cognitive deficits associated with frontal lobe dysfunction can occur in amyotrophic lateral sclerosis (ALS), particularly in individuals with bulbar ALS who can also suffer pathologic emotional lability. Because frontal pathophysiology can alter emotional perception, we examined whether emotional perception deficits occur in ALS, and whether they are related to depressive or dementia symptoms. METHODS: Bulbar ALS participants (n=13) and age-matched healthy normal controls (n=12) completed standardized tests of facial emotional and prosodic recognition, the Geriatric Depression Scale, and the Mini-Mental State Examination. Participants identified the basic emotion (happy, sad, angry, afraid, surprised, disgusted) that matched 39 facial expressions and 28 taped, semantically neutral, intoned sentences. RESULTS: ALS patients performed significantly worse than controls on facial recognition but not on prosodic recognition. Eight of 13 patients (62%) scored below the 95% confidence interval of controls in recognizing facial emotions, and 3 of these patients (23% overall) also scored lower in prosody recognition. Among the 8 patients with emotional perceptual impairment, one-half did not have depressive, or memory or cognitive symptoms on screening, whereas the remainder showed dementia symptoms alone or together with depressive symptoms. CONCLUSIONS: Emotional recognition deficits occur in bulbar ALS, particularly with emotional facial expressions, and can arise independent of depressive and dementia symptoms or comorbid with depression and dementia. These findings expand the scope of cognitive dysfunction detected in ALS, and bolsters the view of ALS as a multisystem disorder involving cognitive and also motor deficits.     

Duration and frequency mismatch negativity in schizophrenia.

OBJECTIVES: The aim of the present study was to elucidate the reasons for apparent inconsistencies in the schizophrenia literature with respect to the mismatch negativity (MMN) waveform of the event-related potential (ERP). While most previous research has shown that MMN is reduced in schizophrenia, there are a small number of studies reporting that frequency MMN is not reduced. METHODS: We recorded ERPs to auditory stimuli with different frequencies and durations from patients with schizophrenia (N = 14) and control subjects (N = 17) of similar age and sex. MMNs to small but discriminable frequency deviants were contrasted with large frequency deviants and duration deviants. RESULTS: Only the MMN to duration deviants was significantly reduced in patients, although there was evidence of a similar trend for large frequency deviants. CONCLUSIONS: The results together with a review of the frequency MMN literature suggest that there are 3 variables which are important in determining whether patients exhibit a reduced MMN to frequency deviants: deviant probability, degree of deviance and interstimulus interval. The results also indicated that patients with schizophrenia may have particular deficits in processing the temporal properties of auditory stimuli. This finding has implications for the pathophysiology of the disorder as time-dependent processing is reliant on the integrity of an extensive network of brain areas consisting of auditory cortex, areas of pre-frontal cortex, the basal ganglia and cerebellum.