Altered lateralisation of emotional prosody processing in schizophrenia

Alterations of cerebral lateralisation in schizophrenia have been reported consistently, and a reduced left-lateralisation has been suggested for language functions. Speech contains non-verbal information, e.g. prosody, and on a behavioural level, the extraction of emotional information from prosody is often impaired in schizophrenia. A previous functional magnetic resonance imaging study suggests increased left-lateralisation in schizophrenia during prosody processing, but did not disentangle effects of speech processing as such and emotional prosody processing. Here, we used meaningless syllables spoken with neutral, angry or fearful speech melody and measured blood oxygen level-dependent (BOLD) responses in 15 in-patients with schizophrenia and 15 healthy control participants matched for age and gender. Lateralisation indices were calculated for responses to emotional versus neutral prosody, and for all types of prosody versus baseline. Compared to control participants, patients with schizophrenia showed an increased right-lateralisation of emotional and non-emotional prosody processing in the temporal and parietal cortex. This right-lateralisation was increased in patients with reduced right-handedness and decreased in patients with stronger negative symptoms, particularly affective blunting, and with longer hospitalisation. Although patients with schizophrenia performed worse in emotion identification, this deficit was not related to lateralisation indices. Enhanced right-lateralisation to prosody resembles previous findings on laterality changes in speech processing and might suggest a common underlying cause in the organization of language functions.     

Differential hedonic experience and behavioral activation in schizophrenia and bipolar disorder

The Kraepelinian distinction between schizophrenia (SZ) and bipolar disorder (BP) emphasizes affective and volitional impairment in the former, but data directly comparing the two disorders for hedonic experience are scarce. This study examined whether hedonic experience and behavioral activation may be useful phenotypes distinguishing SZ and BP. Participants were 39 SZ and 24 BP patients without current mood episode matched for demographics and negative affect, along with 36 healthy controls (HC). They completed the Chapman Physical and Social Anhedonia Scales, Temporal Experience of Pleasure Scale (TEPS), and Behavioral Activation Scale (BAS). SZ and BP showed equally elevated levels of self-report negative affect and trait anhedonia compared to HC. However, SZ reported significantly lower pleasure experience (TEPS) and behavioral activation (BAS) than BP, who did not differ from HC. SZ and BP showed differential patterns of relationships between the hedonic experience and behavioral activation measures. Overall, the results suggest that reduced hedonic experience and behavioral activation may be effective phenotypes distinguishing SZ from BP even when affective symptoms are minimal. However, hedonic experience differences between SZ and BP are sensitive to measurement strategy, calling for further research on the nature of anhedonia and its relation to motivation in these disorders.     

Dissociation of rated emotional valence and Stroop interference in observer-rated alexithymia

OBJECTIVE: The objective of this study was to investigate a theoretically predicted deficit in the capacity to process emotions in alexithymia. The performance of patients high and that of patients low in alexithymia was tested in a computerized emotional Stroop task. METHODS: Reaction times of high and low self- and observer-rated alexithymia groups of 45 psychosomatic inpatients were compared. The task was to name the color of emotionally neutral, positive, negative, and bodily-symptom words as quickly as possible. RESULTS: As expected, patients rated high versus those rated low in alexithymia by observers (but not by self-rating) showed a significantly lesser emotional bias for emotionally negative words and bodily-symptom words but did not differ in their explicit rating of the emotional valence of the words. CONCLUSION: This dissociation between explicit and implicit reactions to the emotional valence of word stimuli suggests that patients high in alexithymia spontaneously allocate less processing resources to negative information.     

Abnormal processing of emotional prosody in Williams syndrome: an event-related potentials study

Williams syndrome (WS), a neurodevelopmental genetic disorder due to a microdeletion in chromosome 7, is described as displaying an intriguing socio-cognitive phenotype. Deficits in prosody production and comprehension have been consistently reported in behavioral studies. It remains, however, to be clarified the neurobiological processes underlying prosody processing in WS.This study aimed at characterizing the electrophysiological response to neutral, happy, and angry prosody in WS, and examining if this response was dependent on the semantic content of the utterance. A group of 12 participants (5 female and 7 male), diagnosed with WS, with age range between 9 and 31 years, was compared with a group of typically developing participants, individually matched for chronological age, gender and laterality. After inspection of EEG artifacts, data from 9 participants with WS and 10 controls were included in ERP analyses.Participants were presented with neutral, positive and negative sentences, in two conditions: (1) with intelligible semantic and syntactic information; (2) with unintelligible semantic and syntactic information (‘pure prosody’ condition). They were asked to decide which emotion was underlying the auditory sentence.Atypical event-related potentials (ERP) components were related with prosodic processing (N100, P200, N300) in WS. In particular, reduced N100 was observed for prosody sentences with semantic content; more positive P200 for sentences with semantic content, in particular for happy and angry intonations; and reduced N300 for both types of sentence conditions.These findings suggest abnormalities in early auditory processing, indicating a bottom-up contribution to the impairment in emotional prosody processing and comprehension. Also, at least for N100 and P200, they suggest the top-down contributions of semantic processes in the sensory processing of speech. This study showed, for the first time, that abnormalities in ERP measures of early auditory processing in WS are also present during the processing of emotional vocal information. This may represent a physiological signature of underlying impaired on-line language and socio-emotional processing.     

The attenuation of dysfunctional emotional processing with stimulant medication: An fMRI study of adolescents with ADHD

Functional neuroimaging studies of attention-deficit/hyperactivity disorder (ADHD) have focused on the neural correlates of cognitive control. However, for many youths with ADHD, emotional lability is an important clinical feature of the disorder. We aimed to identify the neural substrates associated with emotional lability that were distinct from impairments in cognitive control and to assess the effects that stimulants have on those substrates. We used functional magnetic resonance imaging (fMRI) to assess neural activity in adolescents with (N = 15) and without (N = 15) ADHD while they performed cognitive and emotional versions of the Stroop task that engage cognitive control and emotional processing, respectively. The participants with ADHD were scanned both on and off stimulant medication in a counterbalanced fashion. Controlling for differences in cognitive control, we found that during the emotional Stroop task, adolescents with ADHD as compared with controls demonstrated atypical activity in the medial prefrontal cortex (mPFC). Stimulants attenuated activity in the mPFC to levels comparable with controls.     

抑郁症患者外显性与内隐性情绪处理的脑功能磁共振研究

目的以健康者为对照,利用脑功能磁共振研究抑郁症患者的外显性和内隐性情绪处理过程。方法2006年12月-2007年12月,收集临床诊断抑郁症患者14例（DSM-Ⅳ标准）。14例健康志愿者作为对照。采用传统的组块设计,采集患者在高兴与悲伤2组脸像刺激下,判断表情的外显性情绪处理和判断性别的内隐性情绪处理过程的脑功能磁共振图像,利用SPM2统计软件计算出个体及组内在不同表情刺激和不同任务操作下激活的脑功能区。结果①抑郁症患者判断表情时,悲伤脸像的主要激活区位于顶叶、海马旁回、基底节、梭状回、丘脑、岛叶、前扣带回及胼胝体下回;高兴脸像激活区仅有前扣带回;②抑郁症患者判断性别任务时,悲伤脸像激活区分布在额中回、顶下小叶、前扣带回、颞中回;高兴脸像未见明显脑功能激活区。结论①抑郁症患者外显性与内隐性情绪刺激的脑内加工过程不同,悲伤脸像脑功能区激活均强于高兴脸像;②与健康人群相比,不同情绪处理过程中,抑郁症患者的高兴脸像激活区较弱,而悲伤脸像的激活明显增强。提示抑郁症患者情绪处理的神经系统存在异常,对正性情绪的神经反应减弱,而对负性情绪的神经反应增强。     

The validity of Psychosis Proneness Scales as vulnerability indicators in recent-onset schizophrenia patients

The Psychosis Proneness Scales developed by the Chapmans and colleagues [Chapman, J.P., Chapman, L.J., Kwapil, T.R. Scales for the measurement of schizotypy. In: Raine., A., Lencz, T., Mednick, S.A., (Eds.). Schizotypal Personality. New York: Cambridge University Press, 1995. pp. 79–109] are widely used to identify non-patient individuals who are hypothesized to possess heightened vulnerability to schizophrenia and related psychopathology. Yet surprisingly little is known about whether schizophrenia patients themselves show abnormalities on these scales across different clinical states, as would be expected for vulnerability indicators. Scores on four of the Psychosis Proneness Scales were evaluated at three assessment points over a 15-month period in healthy controls (n = 54) and in recent-onset schizophrenia patients (n = 72) who experienced symptom fluctuations across assessments. Patients showed steady elevations on the Physical Anhedonia Scale across time and clinical state, consistent with a stable vulnerability indicator. Patients had higher scores on the Perceptual Aberration and Magical Ideation Scales than controls throughout the follow-up period but scores also changed across clinical states, consistent with a mediating vulnerability indicator. Patients had higher scores on the Impulsive Non-Conformity Scale than controls only during a psychotic state, reflecting an episode indicator. The longitudinal characteristics of these scales in people who are actually diagnosed with schizophrenia provide key evidence for the validity of three commonly used psychometric indicators of vulnerability to psychosis.     

Auditory spatial deficits following hemispheric lesions: Dissociation of explicit and implicit processing

Auditory spatial deficits occur frequently after hemispheric damage; a previous case report suggested that the explicit awareness of sound positions, as in sound localisation, can be impaired while the implicit use of auditory cues for the segregation of sound objects in noisy environments remains preserved. By assessing systematically patients with a first hemispheric lesion, we have shown that (1) explicit and/or implicit use can be disturbed; (2) impaired explicit vs. preserved implicit use dissociations occur rather frequently; and (3) different types of sound localisation deficits can be associated with preserved implicit use. Conceptually, the dissociation between the explicit and implicit use may reflect the dual-stream dichotomy of auditory processing. Our results speak in favour of systematic assessments of auditory spatial functions in clinical settings, especially when adaptation to auditory environment is at stake. Further, systematic studies are needed to link deficits of explicit vs. implicit use to disability in everyday activities, to design appropriate rehabilitation strategies, and to ascertain how far the explicit and implicit use of spatial cues can be retrained following brain damage.     

Auditory spatial deficits following hemispheric lesions: Dissociation of explicit and implicit processing

Auditory spatial deficits occur frequently after hemispheric damage; a previous case report suggested that the explicit awareness of sound positions, as in sound localisation, can be impaired while the implicit use of auditory cues for the segregation of sound objects in noisy environments remains preserved. By assessing systematically patients with a first hemispheric lesion, we have shown that (1) explicit and/or implicit use can be disturbed; (2) impaired explicit vs. preserved implicit use dissociations occur rather frequently; and (3) different types of sound localisation deficits can be associated with preserved implicit use. Conceptually, the dissociation between the explicit and implicit use may reflect the dual-stream dichotomy of auditory processing. Our results speak in favour of systematic assessments of auditory spatial functions in clinical settings, especially when adaptation to auditory environment is at stake. Further, systematic studies are needed to link deficits of explicit vs. implicit use to disability in everyday activities, to design appropriate rehabilitation strategies, and to ascertain how far the explicit and implicit use of spatial cues can be retrained following brain damage.     

Abnormalities in the processing of emotional prosody from single words in schizophrenia

BackgroundAbnormalities in emotional prosody processing have been consistently reported in schizophrenia and are related to poor social outcomes. However, the role of stimulus complexity in abnormal emotional prosody processing is still unclear.MethodWe recorded event-related potentials in 16 patients with chronic schizophrenia and 16 healthy controls to investigate: 1) the temporal course of emotional prosody processing; and 2) the relative contribution of prosodic and semantic cues in emotional prosody processing. Stimuli were prosodic single words presented in two conditions: with intelligible (semantic content condition—SCC) and unintelligible semantic content (pure prosody condition—PPC).ResultsRelative to healthy controls, schizophrenia patients showed reduced P50 for happy PPC words, and reduced N100 for both neutral and emotional SCC words and for neutral PPC stimuli. Also, increased P200 was observed in schizophrenia for happy prosody in SCC only. Behavioral results revealed higher error rates in schizophrenia for angry prosody in SCC and for happy prosody in PPC.ConclusionsTogether, these data further demonstrate the interactions between abnormal sensory processes and higher-order processes in bringing about emotional prosody processing dysfunction in schizophrenia. They further suggest that impaired emotional prosody processing is dependent on stimulus complexity.     

Mismatch negativity (MMN) stands at the crossroads between explicit and implicit emotional processing

The amygdala is known as a key brain region involved in the explicit and implicit processing of emotional faces, and plays a crucial role in salience detection. Not until recently was the mismatch negativity (MMN), a component of the event‐related potentials to an odd stimulus in a sequence of stimuli, utilized as an index of preattentive salience detection of emotional voice processing. However, their relationship remains to be delineated. This study combined the fMRI scanning and event‐related potential recording by examining amygdala reactivity in response to explicit and implicit (backward masked) perception of fearful and angry faces, along with recording MMN in response to the fearfully and angrily spoken syllables dada in healthy subjects who varied in trait anxiety (STAI‐T). Results indicated that the amplitudes of fearful MMN were positively correlated with left amygdala reactivity to explicit perception of fear, but negatively correlated with right amygdala reactivity to implicit perception of fear. The fearful MMN predicted STAI‐T along with left amygdala reactivity to explicit fear, whereas the association between fearful MMN and STAI‐T was mediated by right amygdala reactivity to implicit fear. These findings suggest that amygdala reactivity in response to explicit and implicit threatening faces exhibits opposite associations with emotional MMN. In terms of emotional processing, MMN not only reflects preattentive saliency detection but also stands at the crossroads of explicit and implicit perception. Hum Brain Mapp 38:140–150, 2017. © 2016 Wiley Periodicals, Inc.     

Interparental conflict and adolescents' self-representations: The role of emotional insecurity

Adolescents' signs of emotional insecurity in the context of interparental conflict (IC) – emotional reactivity, internal representations (i.e., constructive/destructive; spillover) and behavioral responses (i.e., withdrawal; inhibition; involvement) – were examined as mediators in the relation between IC and adolescents' self-representations. Self-reported measures were filled out by 221 Portuguese adolescents (59.3% girls; Mage = 12.91), attending public elementary and secondary schools. IC predicted less favorable self-representations. Adolescents' emotional reactivity and withdrawal mediated the relation between IC and emotional and physical appearance self-representations, while conflict spillover representations and constructive family representations mediated associations between IC and instrumental self-representations. This study emphasizes the importance of interparental conflict and adolescent emotional insecurity in the construction of their self-representations, having important theoretical and practical implications. It highlights the value of analyzing the specific role of several emotional insecurity dimensions, and informs practitioners' work aimed at promoting constructive conflict and adaptive emotional regulation skills.     

Emotion-cognition interactions in schizophrenia: Implicit and explicit effects of facial expression

Working memory (WM) and emotion classification are amongst the cognitive domains where specific deficits have been reported for patients with schizophrenia. In healthy individuals, the capacity of visual working memory is enhanced when the material to be retained is emotionally salient, particularly for angry faces. We investigated whether patients with schizophrenia also have an enhanced WM capacity for angry faces. We compared 34 inpatients with schizophrenia and 34 age-, handedness- and gender-matched control participants in three separate tasks. In the WM task, participants saw two faces with angry, happy or neutral emotional expressions for 2 s and had to decide whether a probe face presented after a 1 s delay was identical to one of them. In the emotion classification task, they had to assign these faces to the appropriate categorical emotion. They also rated faces for valence and arousal. Although patients performed generally worse on the working memory task, they showed the same benefit for angry faces as control participants. However, patients were specifically impaired for angry faces on the emotion classification task. These results indicate preserved implicit emotion processing in schizophrenia patients, which contrasts with their impairment in explicit emotion classification. With regard to clinical practice, our findings underline the importance of assessing responsiveness to emotions in patients with schizophrenia, with a view possibly to utilize preserved implicit emotion processing in cognitive remediation programs.     

Reduced implicit and explicit sequence learning in first-episode schizophrenia

A high prevalence of deficits in explicit learning has been reported for schizophrenic patients, but it is less clear whether these patients are impaired in implicit learning. Deficits in implicit learning indicative of a fronto-striatal dysfunction have been reported using a serial reaction-time task (SRT), but the impact of typical neuroleptic medication and chronicity remains controversial. The present study compared 37 patients with first-episode schizophrenia treated with atypical neuroleptics and 37 healthy matched control participants on two sequence learning tasks: a modified SRT for implicit sequence learning and a serial generation task (SGT) for explicit sequence learning. The two tasks were designed to be procedurally equivalent, in order to provide better comparability between implicit and explicit performance. Although unaffected in global cognitive functioning, schizophrenic patients were significantly impaired in implicit and explicit sequence learning. Deficient sequence learning in schizophrenic patients was neither related to psychopathology nor to chlorpromazine equivalent daily dosage. As performance was impaired even though patients were exclusively treated with atypical neuroleptics, the present findings concur with converging evidence of a sequence learning deficit inherent in schizophrenia. This deficit would be consistent with a fronto-striatal dysfunction and might constitute a crucial factor for the acquisition of new information.     

Impaired recognition and expression of emotional prosody in schizophrenia: review and meta-analysis

BACKGROUND: Deficits in emotion processing may be one of the most pervasive disturbances in schizophrenia that may contribute to social isolation. In this report we focus on vocal emotion processing. This function bears upon two corner stones of social functioning, language and emotion, which have both been found to be impaired in schizophrenia. METHODS: We used meta-analysis to integrate findings of studies published between 1980 and June 2007 on perception of emotional prosody in schizophrenia. 17 studies provided sufficient information to be included. A mean weighted effect size was computed in the random effects model. Publication bias was tested using funnel plots and fail-safe number of studies. Seven studies were included in an analysis on the expression (i.e. production) of emotional prosody in schizophrenia. RESULTS: A significant and stable mean weighted effect size was found for the perception of emotional prosody, d=-1.24, 95% CI=-1.55 to -0.93. The effect was also found in the early stages of the illness. Expression of emotional prosody was also significantly impaired, d=-1.11, 95% CI=-1.78 to -0.43. CONCLUSIONS: Results indicate that individuals with schizophrenia are impaired in the perception and expression of emotional prosody, with a large effect size. As a growing body of evidence shows that impaired social cognition in schizophrenia may be an important predictor of social outcome, training programs that aim at the recognition of emotional prosody should be developed.     

Neural correlates of processing emotional prosody in unipolar depression

Major depressive disorder (MDD) is characterized by a biased emotion perception. In the auditory domain, MDD patients have been shown to exhibit attenuated processing of positive emotions expressed by speech melody (prosody). So far, no neuroimaging studies examining the neural basis of altered processing of emotional prosody in MDD are available. In this study, we addressed this issue by examining the emotion bias in MDD during evaluation of happy, neutral, and angry prosodic stimuli on a five‐point Likert scale during functional magnetic resonance imaging (fMRI). As expected, MDD patients rated happy prosody less intense than healthy controls (HC). At neural level, stronger activation in the middle superior temporal gyrus (STG) and the amygdala was found in all participants when processing emotional as compared to neutral prosody. MDD patients exhibited an increased activation of the amygdala during processing prosody irrespective of valence while no significant differences between groups were found for the STG, indicating that altered processing of prosodic emotions in MDD occurs rather within the amygdala than in auditory areas. Concurring with the valence‐specific behavioral effect of attenuated evaluation of positive prosodic stimuli, activation within the left amygdala of MDD patients correlated with ratings of happy, but not neutral or angry prosody. Our study provides first insights in the neural basis of reduced experience of positive information and an abnormally increased amygdala activity during prosody processing.     

Poor savouring and low self-efficacy are predictors of anhedonia in patients with schizophrenia spectrum disorders

Previous research suggests that negative schizotypes may be impaired in their ability to savour pleasant events (Applegate et al., 2009) and that schizophrenia patients believe that everyday tasks are excessively difficult to complete so that they attempt these tasks less frequently (32 and 10). It is possible that these beliefs and behaviours underpin negative symptoms such as anhedonia, avolition, apathy and associality. In the present study, 50 schizophrenia patients and 100 matched controls (half employed and half unemployed) completed self-report measures of self-efficacy and savouring. Patients reported savouring past, present and future events less than employed and unemployed groups, irrespective of mood state and I.Q. Patients also rated everyday tasks as more difficult to master. Inpatients compared to outpatients rated tasks more difficult but less important although they did not differ on the savouring measure. Abnormal judgements of difficulty and the reduced propensity to mentally rehearse past or future positive experiences to up-regulate mood could explain negative symptom patients' lack of engagement in everyday activities and eventual social withdrawal. These findings suggest the need to develop cognitive-behavioural savouring and self-efficacy interventions for patients experiencing the negative symptoms of schizophrenia.     

Non-voluntary and voluntary processing of emotional prosody: an event-related potentials study

The present study investigated whether event-related potentials (ERPs) reflect non-voluntary vs voluntary processing of emotional prosody. ERPs were obtained while participants processed emotional information non-voluntarily (i.e. while evaluating semantic characteristics of a stimulus) and voluntarily (i.e. while evaluating emotional characteristics of a stimulus). Results suggest that emotional prosody is processed around 160 ms after stimulus onset under non-voluntary processing conditions (when the attention is diverted from the emotional meaning of the tone of voice); and around 360 ms under voluntary processing conditions. The findings support the notion that emotional prosody is processed non-voluntarily in the comprehension of a spoken message.     

Preliminary evidence of an interaction between the FOXP2 gene and childhood emotional abuse predicting likelihood of auditory verbal hallucinations in schizophrenia

ObjectiveThe FOXP2 gene is involved in the development of speech and language. As some single nucleotide polymorphisms (SNPs) of FOXP2 have been found to be associated with auditory verbal hallucinations (AVHs) at trend levels, this study set out to undertake the first examination into whether interactions between candidate FOXP2 SNPs and environmental factors (specifically, child abuse) predict the likelihood of AVHs.MethodData on parental child abuse and FOXP2 SNPs previously linked to AVHs (rs1456031, rs2396753, rs2253478) were obtained from the Australian Schizophrenia Research Bank for people with schizophrenia-spectrum disorders, both with (n = 211) and without (n = 122) a lifetime history of AVHs.ResultsGenotypic frequencies did not differ between the two groups; however, logistic regression found that childhood parental emotional abuse (CPEA) interacted with rs1456031 to predict lifetime experience of AVH. CPEA was only associated with significantly higher levels of AVHs in people with CC genotypes (odds ratio = 4.25), yet in the absence of CPEA, people with TT genotypes had significantly higher levels of AVHs than people with CC genotypes (odds ratio = 4.90). This interaction was specific to auditory verbal hallucinations, and did not predict the likelihood of non-verbal auditory hallucinations.ConclusionsOur findings offer tentative evidence that FOXP2 may be a susceptibility gene for AVHs, influencing the probability people experience AVHs in the presence and absence of CPEA. However, these findings are in need of replication in a larger study that addresses the methodological limitations of the present investigation.