Not pitch perfect: sensory contributions to affective communication impairment in schizophrenia

Social Cognition and Functional Connectivity in Early and Chronic Schizophrenia

BACKGROUND

Individuals with schizophrenia (SZ) experience impairments in social cognition that contribute to poor functional outcomes. However, mechanisms of social cognitive dysfunction in SZ remain poorly understood, which impedes the design of novel interventions to improve outcomes. This pre-registered project (https://doi.org/10.17605/OSF.IO/JH5FC) examines the representation of social cognition in the brain's functional architecture across early and chronic SZ.

METHODS

The study contains two parts: a confirmatory and an exploratory portion. In the confirmatory portion, we identified resting-state connectivity disruptions evident in early and chronic SZ. We performed a connectivity analysis using regions associated with social cognitive dysfunction in early and chronic SZ to test whether aberrant connectivity observed in chronic SZ (N=47; HC=52) was also present in early SZ (N=71, HC=47). In the exploratory portion, we assessed the out-of-sample generalizability and precision of predictive models of social cognition. We used machine learning to predict social cognition and established generalizability with out-of-sample testing and confound control.

RESULTS

Results reveal decreases between left inferior frontal gyrus and intraparietal sulcus in early and chronic SZ, which are significantly associated with social and general cognition and global functioning in chronic SZ and with general cognition and global functioning in early SZ. Predictive modeling reveals the importance of out-of-sample evaluation and confound control.

CONCLUSION

This work provides insights into the functional architecture in early and chronic SZ and suggests that IFG-IPS connectivity could be a prognostic biomarker of social impairments and a target for future interventions (e.g. neuromodulation) focused on improved social functioning.

Speech changes in old age: Methodological considerations for speech-based discrimination of healthy ageing and Alzheimer's disease

BACKGROUND

Recent evidence suggests that speech substantially changes in ageing. As a complex neurophysiological process, it can accurately reflect changes in the motor and cognitive systems underpinning human speech. Since healthy ageing is not always easily discriminable from early stages of dementia based on cognitive and behavioural hallmarks, speech is explored as a preclinical biomarker of pathological itineraries in old age. A greater and more specific impairment of neuromuscular activation, as well as  a specific cognitive and linguistic impairment in dementia, unchain discriminating changes in speech. Yet, there is no consensus on such discriminatory speech parameters, neither on how they should be elicited and assessed.

AIMS

To provide a state-of-the-art on speech parameters that allow for early discrimination between healthy and pathological ageing; the aetiology of these parameters; the effect of the type of experimental stimuli on speech elicitation and the predictive power of different speech parameters; and the most promising methods for speech analysis and their clinical implications.

METHODS & PROCEDURES

A scoping review methodology is used in accordance with the PRISMA model. Following a systematic search of PubMed, PsycINFO and CINAHL, 24 studies are included and analysed in the review.

MAIN CONTRIBUTION

The results of this review yield three key questions for the clinical assessment of speech in ageing. First, acoustic and temporal parameters are more sensitive to changes in pathological ageing and, of these two, temporal variables are more affected by cognitive impairment. Second, different types of stimuli can trigger speech parameters with different degree of accuracy for the discrimination of clinical groups. Tasks with higher cognitive load are more precise in eliciting higher levels of accuracy. Finally, automatic speech analysis for the discrimination of healthy and pathological ageing should be improved for both research and clinical practice.

CONCLUSIONS & IMPLICATIONS

Speech analysis is a promising non-invasive tool for the preclinical screening of healthy and pathological ageing. The main current challenges of speech analysis in ageing are the automatization of its clinical assessment and the consideration of the speaker's cognitive background during evaluation.

WHAT THIS PAPER ADDS

What is already known on the subject Societal aging  goes hand in hand with the rising incidence of ageing-related neurodegenerations, mainly Alzheimer's disease (AD). This is particularly noteworthy in countries with longer life expectancies. Healthy ageing and early stages of AD share a set of cognitive and behavioural characteristics. Since there is no cure for dementias, developing methods for accurate discrimination of healthy ageing and early AD is currently a priority. Speech has been described as one of the most significantly impaired features in AD. Neuropathological alterations in motor and cognitive systems would underlie specific speech impairment in dementia. Since speech can be evaluated quickly, non-invasively and inexpensively, its value for the clinical assessment of ageing itineraries may be particularly high. What this paper adds to existing knowledge Theoretical and experimental advances in the assessment of speech as a marker of AD have developed rapidly over the last decade. Yet, they are not always known to clinicians. Furthermore, there is a need to provide an updated state-of-the-art on which speech features are discriminatory to AD, how they can be assessed, what kind of results they can yield, and how such results should be interpreted. This article provides an updated overview of speech profiling, methods of speech measurement and analysis, and the clinical power of speech assessment for early discrimination of AD as the most common cause of dementia. What are the potential or actual clinical implications of this work? This article provides an overview of the predictive potential of different speech parameters in relation to AD cognitive impairment. In addition, it discusses the effect that the cognitive state, the type of elicitation task and the type of assessment method may have on the results of the speech-based analysis in ageing.

Longitudinal Investigation of Auditory Dynamic Range Deficits in Early Psychosis and its Relationship to Negative Symptoms

BACKGROUND AND HYPOTHESIS

Despite accounting for significant disease morbidity in schizophrenia, the neuropathological basis of negative symptoms remains poorly understood and options for treatment limited. Our recent study identified robust associations between diminished auditory cortex (AC) dynamic range and social functioning impairments and negative symptoms in first episode psychosis (FESz). The current investigation examined the progression of these relationships 4-8 months from baseline testing.

STUDY DESIGN

Twenty-six FESz and 38 healthy controls (HC) were tested at baseline and follow-up. Magnetoencephalography (MEG) was recorded during binaural presentation of tones (75, 80, and 85 dB). Assessments included the MATRICS cognitive consensus battery (MCCB) and Global Functioning: Role and Social scales (GFR/GFS) and the Positive and Negative Syndrome Scale.

STUDY RESULTS

Overall, FESz exhibited a blunted response to increasing tone intensity relative to HC. While this deficit did not change over time at the group level, recovery of right hemisphere AC dynamic range (85-75 dB response) among FESz individuals was associated with reductions in negative symptoms (ρ = -0.50). Diminished dynamic range was also associated with impaired GFS (ρ = 0.65), GFR (ρ = 0.51), and MCCB (ρ = 0.49) at baseline and increased negative symptoms at baseline (ρ = -0.53) and follow-up (ρ = -0.51).

CONCLUSION

Despite persistent dynamic range impairment in FESz as a group, individual recovery of this AC response property was associated with significant reduction in negative symptoms. Identification of a functional neural deficit that tracts progression of negative symptoms during a critical period for disease modification is essential to the management of these devastating and historically treatment refractory symptoms.

Dose-Dependent Augmentation of Neuroplasticity-Based Auditory Learning in Schizophrenia: A Double-Blind, Placebo-Controlled, Randomized, Target Engagement Clinical Trial of the NMDA Glutamate Receptor Agonist d-serine

BACKGROUND

Patients with schizophrenia show reduced NMDA glutamate receptor-dependent auditory plasticity, which is rate limiting for auditory cognitive remediation (AudRem). We evaluate the utility of behavioral and neurophysiological pharmacodynamic target engagement biomarkers, using a d-serine+AudRem combination.

METHODS

Forty-five participants with schizophrenia or schizoaffective disorder were randomized to 3 once-weekly AudRem visits + double-blind d-serine (80, 100, or 120 mg/kg) or placebo in 3 dose cohorts of 12 d-serine and 3 placebo-treated participants each. In AudRem, participants indicated which paired tone was higher in pitch. The primary outcome was plasticity improvement, operationalized as change in pitch threshold between AudRem tones [(test tone Hz - reference tone Hz)/reference tone Hz] between the initial plateau pitch threshold (mean of trials 20-30 of treatment visit 1) to pitch threshold at the end of visit(s). Target engagement was assessed by electroencephalography outcomes, including mismatch negativity (pitch primary).

RESULTS

There was a significant overall treatment effect for plasticity improvement (p = .014). Plasticity improvement was largest within the 80 and 100 mg/kg groups (p < .001, d > 0.67), while 120 mg/kg and placebo-treated participants showed nonsignificant within-group changes. Plasticity improvement was seen after a single treatment and was sustained on subsequent treatments. Target engagement was demonstrated by significantly larger mismatch negativity (p = .049, d = 1.0) for the 100 mg/kg dose versus placebo.

CONCLUSIONS

Our results demonstrate sufficient proof of principle for continued development of both the d-serine+AudRem combination and our target engagement methodology. The ultimate utility is dependent on the results of an ongoing larger, longer study of the combination for clinically relevant outcomes.

Negative-emotion-induced reduction in speech-in-noise recognition is associated with source-monitoring deficits and psychiatric symptoms in mandarin-speaking patients with schizophrenia

BACKGROUND

Patients with schizophrenia (SCH) have deficits in source monitoring (SM), speech-in-noise recognition (SR), and auditory prosody recognition. This study aimed to test the covariation between SM and SR alteration induced by negative prosodies and their association with psychiatric symptoms in SCH.

METHODS

Fifty-four SCH patients and 59 healthy controls (HCs) underwent a speech SM task, an SR task, and the assessment of positive and negative syndrome scale (PANSS). We used the multivariate analyses of partial least squares (PLS) regression to explore the associations among SM (external/internal/new attribution error [AE] and response bias [RB]), SR alteration/release induced by four negative-emotion (sad, angry, fear, and disgust) prosodies of target speech, and psychiatric symptoms.

RESULTS

In SCH, but not HCs, a profile (linear combination) of SM (especially the external-source RB) was positively associated with a profile of SR reductions (induced especially by the angry prosody). Moreover, two SR reduction profiles (especially in the anger and sadness conditions) were related to two profiles of psychiatric symptoms (negative symptoms, lack of insight, and emotional disturbances). The two PLS components explained 50.4% of the total variances of the release-symptom association.

CONCLUSION

Compared to HCs, SCH is more likely to perceive the external-source speech as internal/new source speech. The SM-related SR reduction induced by the angry prosody was mainly associated with negative symptoms. These findings help understand the psychopathology of SCH and may provide a potential direction to improve negative symptoms via minimizing emotional SR reduction in schizophrenia.

Early auditory processing dysfunction in schizophrenia: Mechanisms and implications

Schizophrenia is a major mental disorder that affects approximately 1% of the population worldwide. Cognitive deficits are a key feature of the disorder and a primary cause of long-term disability. Over the past decades, significant literature has accumulated demonstrating impairments in early auditory perceptual processes in schizophrenia. In this review, we first describe early auditory dysfunction in schizophrenia from both a behavioral and neurophysiological perspective and examine their interrelationship with both higher order cognitive constructs and social cognitive processes. Then, we provide insights into underlying pathological processes, especially in relationship to glutamatergic and N-methyl-D-aspartate receptor (NMDAR) dysfunction models. Finally, we discuss the utility of early auditory measures as both treatment targets for precision intervention and as translational biomarkers for etiological investigation. Altogether, this review points out the crucial role of early auditory deficits in the pathophysiology of schizophrenia, in addition to major implications for early intervention and auditory-targeted approaches.

Connecting Neurobiological Features with Interregional Dysconnectivity in Social-Cognitive Impairments of Schizophrenia

Schizophrenia (SZ) is a devastating psychiatric disorder affecting about 1% of the world's population. Social-cognitive impairments in SZ prevent positive social interactions and lead to progressive social withdrawal. The neurobiological underpinnings of social-cognitive symptoms remain poorly understood, which hinders the development of novel treatments. At the whole-brain level, an abnormal activation of social brain regions and interregional dysconnectivity within social-cognitive brain networks have been identified as major contributors to these symptoms. At the cellular and subcellular levels, an interplay between oxidative stress, neuroinflammation and N-methyl-D-aspartate receptor hypofunction is thought to underly SZ pathology. However, it is not clear how these molecular processes are linked with interregional dysconnectivity in the genesis of social-cognitive symptoms. Here, we aim to bridge the gap between macroscale (connectivity analyses) and microscale (molecular and cellular mechanistic) knowledge by proposing impaired myelination and the disinhibition of local microcircuits as possible causative biological pathways leading to dysconnectivity and abnormal activity of the social brain. Furthermore, we recommend electroencephalography as a promising translational technique that can foster pre-clinical drug development and discuss attractive drug targets for the treatment of social-cognitive symptoms in SZ.

Basic auditory processing and its relationship with symptoms in patients with schizophrenia: A systematic review

Processing of basic auditory features, one of the earliest stages of auditory perception, has been the focus of considerable investigations in schizophrenia. Although numerous studies have shown abnormalities in pitch perception in schizophrenia, other basic auditory features such as intensity, duration, and sound localization have been less explored. Additionally, the relationship between basic auditory features and symptom severity shows inconsistent results, preventing concrete conclusions. Our aim was to present a comprehensive overview of basic auditory processing in schizophrenia and its relationship with symptoms. We conducted a systematic review according to the PRISMA guidelines. PubMed, Embase, and PsycINFO databases were searched for studies exploring auditory perception in schizophrenia compared to controls, with at least one behavioral task investigating basic auditory processing using pure tones. Forty-one studies were included. The majority investigated pitch processing while the others investigated intensity, duration and sound localization. The results revealed that patients have a significant deficit in the processing of all basic auditory features. Although the search for a relationship with symptoms was limited, auditory hallucinations experience appears to have an impact on basic auditory processing. Further research may examine correlations with clinical symptoms to explore the performance of patient subgroups and possibly implement remediation strategies.

Vocal acoustic features may be objective biomarkers of negative symptoms in schizophrenia: A cross-sectional study

BACKGROUND

There are currently no objective biomarkers that allow the quantification of negative symptoms of schizophrenia. This study therefore explored the use of acoustic features in identifying the severity of negative symptoms in patients with schizophrenia.

METHODS

We recruited 79 inpatients who were diagnosed with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (the schizophrenia group) at the Huilongguan Hospital in Beijing, China, and 79 healthy controls from the surrounding community (the control group). We assessed the clinical symptoms of the patients with schizophrenia using the Positive and Negative Syndrome Scale (PANSS) and the Brief Negative Symptom Scale (BNSS) and recorded the voice of each participant as they read emotionally positive, neutral, and negative texts. The Praat software was used to analyse and extract acoustic characteristics from the recordings, such as jitter, shimmer, and pitch. The acoustic differences between the two groups of participants and the relationship between acoustic characteristics and clinical symptoms in the patient group were analysed.

RESULTS

There were significant differences between the schizophrenia and control groups in pitch, voice breaks, jitter, shimmer, and the mean harmonics-to-noise ratio (p < 0.05). Jitter was negatively correlated with the blunted affect and alogia subscale scores of the BNSS, both in the positive and neutral emotion conditions, but the correlation disappeared in the negative emotion condition. However, shimmer exhibited a stable negative correlation with the blunted affect and alogia subscale scores of the BNSS in all three emotion conditions. A linear regression analysis showed that pitch, jitter, shimmer, and age were statistically significant predictors of BNSS subscale scores.

CONCLUSIONS

Acoustic emotional expression differs between patients with schizophrenia and healthy controls. Some acoustic characteristics are related to the severity of negative symptoms, regardless of semantic emotions, and may therefore be objective biomarkers of negative symptoms. A systematic method for assessing vocal acoustic characteristics could provide an accurate and feasible means of assessing negative symptoms in schizophrenia.

TWEET

Acoustic emotional expression differs between patients with schizophrenia and healthy controls. A systematic method for assessing vocal acoustics could provide an accurate and feasible means of assessing negative symptoms in schizophrenia.

Altered processing of communication signals in the subcortical auditory sensory pathway in autism

Autism spectrum disorder (ASD) is characterised by social communication difficulties. These difficulties have been mainly explained by cognitive, motivational, and emotional alterations in ASD. The communication difficulties could, however, also be associated with altered sensory processing of communication signals. Here, we assessed the functional integrity of auditory sensory pathway nuclei in ASD in three independent functional magnetic resonance imaging experiments. We focused on two aspects of auditory communication that are impaired in ASD: voice identity perception, and recognising speech-in-noise. We found reduced processing in adults with ASD as compared to typically developed control groups (pairwise matched on sex, age, and full-scale IQ) in the central midbrain structure of the auditory pathway (inferior colliculus [IC]). The right IC responded less in the ASD as compared to the control group for voice identity, in contrast to speech recognition. The right IC also responded less in the ASD as compared to the control group when passively listening to vocal in contrast to non-vocal sounds. Within the control group, the left and right IC responded more when recognising speech-in-noise as compared to when recognising speech without additional noise. In the ASD group, this was only the case in the left, but not the right IC. The results show that communication signal processing in ASD is associated with reduced subcortical sensory functioning in the midbrain. The results highlight the importance of considering sensory processing alterations in explaining communication difficulties, which are at the core of ASD.

Auditory emotion recognition deficits in schizophrenia: A systematic review and meta-analysis

BACKGROUND

Auditory emotion recognition (AER) deficits refer to the abnormal identification and interpretation of tonal or prosodic features that transmit emotional information in sounds or speech. Evidence suggests that AER deficits are related to the pathology of schizophrenia. However, the effect size of the deficit in specific emotional category recognition in schizophrenia and its association with psychotic symptoms have never been evaluated through a meta-analysis.

METHODS

A systematic search for literature published in English or Chinese until November 30, 2020 was conducted in PubMed, Embase, Web of Science, PsychINFO, and China National Knowledge Infrastructure (CNKI), WanFang and Weip Databases. AER differences between patients and healthy controls (HCs) were assessed by the standardized mean differences (SMDs). Subgroup analyses were conducted for the type of emotional stimuli and the diagnosis of schizophrenia or schizoaffective disorders (Sch/SchA). Meta-regression analyses were performed to assess the influence of patients' age, sex, illness duration, antipsychotic dose, positive and negative symptoms on the study SMDs.

RESULTS

Eighteen studies containing 615 psychosis (Sch/SchA) and 488 HCs were included in the meta-analysis. Patients exhibited moderate deficits in recognizing the neutral, happy, sad, angry, fear, disgust, and surprising emotion. Neither the semantic information in the auditory stimuli nor the diagnosis subtype affected AER deficits in schizophrenia. Sadness, anger, and disgust AER deficits were each positively associated with negative symptoms in schizophrenia.

CONCLUSIONS

Patients with schizophrenia have moderate AER deficits, which were associated with negative symptoms. Rehabilitation focusing on improving AER abilities may help improve negative symptoms and the long-term prognosis of schizophrenia.

Oxytocin does not improve emotional prosody recognition in schizophrenia-spectrum disorders

Schizophrenia-spectrum disorders (SSD) are associated with deficits in emotional prosody recognition. Whether administration of oxytocin can improve emotional prosody recognition accuracy in SSD is unknown. Sixty individuals with SSD and ninety-seven controls completed a placebo-controlled, double-blind, cross-over trial examining the effects of oxytocin on emotional prosody recognition accuracy. Compared to controls, SSD was associated with poorer emotional prosody recognition accuracy, regardless of stimulus valence or intensity, suggesting a generalized deficit. Oxytocin had no effect on emotional prosody recognition in either group, which is consistent with previous work suggesting that oxytocin only improves high-level social cognition in SSD.

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Deficits in emotional prosody recognition (EPR) are common across the course of schizophrenia-spectrum disorders (SSD).

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Oxytocin (OT) has been shown to improve aspects of social cognition and may ameliorate deficits in EPR.

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Individuals with and without SSD completed an EPR task after receiving OT or placebo in a cross-over design over two visits.

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Individuals with SSD had poorer EPR than controls.

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Oxytocin did not improve EPR in either group.

Neural and functional correlates of impaired reading ability in schizophrenia

Deficits in early auditory processing (EAP) are a core component of schizophrenia (SZ) and contribute significantly to impaired overall function. Here, we evaluate the potential contributions of EAP-related impairments in reading to functional capacity and outcome, relative to effects of auditory social cognitive and general neurocognitive dysfunction. Participants included 30-SZ and 28-controls of similar age, sex, and educational achievement. EAP was assessed using an auditory working memory (tone-matching) task. Phonological processing and reading Fluency were assessed using the Comprehensive Test of Phonological Processing and Woodcock-Johnson reading batteries, respectively. Auditory-related social cognition was assessed using measures of emotion/sarcasm recognition. Functional capacity and outcome were assessed using the UCSD Performance-based Skills Assessment and Specific Level of Functioning scale, respectively. fMRI resting-state functional-connectivity (rsFC) was used to evaluate potential underlying substrates. As predicted, SZ patients showed significant and interrelated deficits in both phonological processing (d = 0.74, p = 0.009) and reading fluency (d = 1.24, p < 0.00005). By contrast, single word reading (d = 0.35, p = 0.31) was intact. In SZ, deficits in EAP and phonological reading ability significantly predicted reduced functional capacity, but not functional outcome. By contrast, deficits in reading fluency significantly predicted impairments in both functional capacity and functional outcome. Moreover, deficits in reading fluency correlated with rsFC alterations among auditory thalamus, early auditory and auditory association regions. These findings indicate significant contributions of EAP deficits and functional connectivity changes in subcortical and early auditory regions to reductions in reading fluency, and of impaired reading ability to impaired functional outcome in SZ.

Hierarchical deficits in auditory information processing in schizophrenia

Deficits in auditory processing contribute significantly to impaired functional outcome in schizophrenia (SZ), but mediating factors remain under investigation. Here we evaluated two hierarchical components of early auditory processing: pitch-change detection (i.e. identifying if 2 tones have "same" or "different" pitch), which is preferentially associated with early auditory cortex, and serial pitch-pattern detection (i.e. identifying if 3 tones have "same" or "different" pitch, and, if "different", which one differed from the others), which depends also on auditory association regions. Deficits in pitch-change detection deficits in SZ have been widely reported and correlated with higher auditory disturbances such as Auditory Emotion Recognition (AER). Deficits in serial pitch-pattern discrimination have been less studied. Here, we investigated both pitch perception components, along with integrity of AER in SZ patients vs. controls using behavioral paradigms. We hypothesized that the deficits could be viewed as hierarchically organized in SZ, with deficits in low-level function propagating sequentially through subsequent levels of processing. Participants included 27 SZ and 40 controls. The magnitude of the deficits in SZ participants was large in both the pitch-change (d = 1.15) and serial pitch-pattern tasks (d = 1.21) with no significant differential task effect. The effect size of the AER deficits was extremely large (d = 2.82). In the SZ group, performance in both pitch tasks correlated significantly with impaired AER performance. However, a mediation analysis showed that serial pitch-pattern detection mediated the relationship between simpler pitch-change detection and AER in patients. Findings are consistent with hierarchical models of cognitive dysfunction in SZ with deficits in early information processing contributing to higher level impairments. Furthermore, findings are consistent with recent neurophysiological results suggesting similar level impairments for processing of simple vs. more complex tonal dysfunction in SZ.

Altered attentional processing of happy prosody in schizophrenia

BACKGROUND

Abnormalities in emotional prosody processing have been consistently reported in schizophrenia. Emotionally salient changes in vocal expressions attract attention in social interactions. However, it remains to be clarified how attention and emotion interact during voice processing in schizophrenia. The current study addressed this question by examining the P3b event-related potential (ERP) component.

METHOD

The P3b was elicited with a modified oddball task, in which frequent (p = .84) neutral stimuli were intermixed with infrequent (p = .16) task-relevant emotional (happy or angry) targets. Prosodic speech was presented in two conditions - with intelligible (semantic content condition - SCC) or unintelligible semantic content (prosody-only condition - POC). Fifteen chronic schizophrenia patients and 15 healthy controls were instructed to silently count the target vocal sounds.

RESULTS

Compared to controls, P3b amplitude was specifically reduced for happy prosodic stimuli in schizophrenia, irrespective of semantic status. Groups did not differ in the processing of neutral standards or angry targets.

DISCUSSION

The selectively reduced P3b for happy prosody in schizophrenia suggests top-down attentional resources were less strongly engaged by positive relative to negative prosody, reflecting alterations in the evaluation of the emotional salience of the voice. These results highlight the role played by higher-order processes in emotional prosody dysfunction in schizophrenia.

What Is Going On? The Process of Generating Questions about Emotion and Social Cognition in Bipolar Disorder and Schizophrenia with Cartoon Situations and Faces

Regarding the notion of putative “best” practices in social neuroscience and science in general, we contend that following established procedures has advantages, but prescriptive uniformity in methodology can obscure flaws, bias thinking, stifle creativity, and restrict exploration. Generating hypotheses is at least as important as testing hypotheses. To illustrate this process, we describe the following exploratory study. Psychiatric patients have difficulties with social functioning that affect their quality of life adversely. To investigate these impediments, we compared the performances of patients with schizophrenia and those with bipolar disorder to healthy controls on a task that involved matching photographs of facial expressions to a faceless protagonist in each of a series of drawn cartoon emotion-related situations. These scenarios involved either a single character (Nonsocial) or multiple characters (Social). The Social scenarios were also Congruent, with everyone in the cartoon displaying the same emotion, or Noncongruent (with everyone displaying a different emotion than the protagonist should). In this preliminary study, both patient groups produced lower scores than controls (p < 0.001), but did not perform differently from each other. All groups performed best on the social-congruent items and worst on the social-noncongruent items (p < 0.001). Performance varied inversely with illness duration, but not symptom severity. Complete emotional, social, cognitive, or perceptual inability is unlikely because these patient groups could still do this task. Nevertheless, the differences we saw could be meaningful functionally and clinically significant and deserve further exploration. Therefore, we stress the need to continue developing novel, alternative ways to explore social cognition in patients with psychiatric disorders and to clarify which elements of the multidimensional process contribute to difficulties in daily functioning.

Temporal signatures of processing voiceness and emotion in sound

This study explored the temporal course of vocal and emotional sound processing. Participants detected rare repetitions in a stimulus stream comprising neutral and surprised non-verbal exclamations and spectrally rotated control sounds. Spectral rotation preserved some acoustic and emotional properties of the vocal originals. Event-related potentials elicited to unrepeated sounds revealed effects of voiceness and emotion. Relative to non-vocal sounds, vocal sounds elicited a larger centro-parietally distributed N1. This effect was followed by greater positivity to vocal relative to non-vocal sounds beginning with the P2 and extending throughout the recording epoch (N4, late positive potential) with larger amplitudes in female than in male listeners. Emotion effects overlapped with the voiceness effects but were smaller and differed topographically. Voiceness and emotion interacted only for the late positive potential, which was greater for vocal-emotional as compared with all other sounds. Taken together, these results point to a multi-stage process in which voiceness and emotionality are represented independently before being integrated in a manner that biases responses to stimuli with socio-emotional relevance.

Neurocircuitry of impaired affective sound processing: A clinical disorders perspective

Decoding affective meaning from sensory information is central to accurate and adaptive behavior in many natural and social contexts. Human vocalizations (speech and non-speech), environmental sounds (e.g. thunder, noise, or animal sounds) and human-produced sounds (e.g. technical sounds or music) can carry a wealth of important aversive, threatening, appealing, or pleasurable affective information that sometimes implicitly influences and guides our behavior. A deficit in processing such affective information is detrimental to adaptive environmental behavior, psychological well-being, and social interactive abilities. These deficits can originate from a diversity of psychiatric and neurological disorders, and are associated with neural dysfunctions across largely distributed brain networks. Recent neuroimaging studies in psychiatric and neurological patients outline the cortical and subcortical neurocircuitry of the complimentary and differential functional roles for affective sound processing. This points to and confirms a recently proposed distributed network rather than a single brain region underlying affective sound processing, and highlights the notion of a multi-functional process that can be differentially impaired in clinical disorders.

The effect of bilateral transcranial direct current stimulation on early auditory processing in schizophrenia: a preliminary study

Transcranial direct current stimulation (tDCS) was applied bilaterally over the auditory cortex in 12 schizophrenia patients to modulate early auditory processing. Performance on a tone discrimination task (tone-matching task-TMT) and auditory mismatch negativity were assessed after counterbalanced anodal, cathodal, and sham tDCS. Cathodal stimulation improved TMT performance (p < 0.03) compared to sham condition. Post-hoc analyses revealed a stimulation condition by negative symptom interaction in which greater negative symptoms were associated with a better TMT performance after anodal tDCS.

Tone-matching ability in patients with schizophrenia: A systematic review and meta-analysis

CONTEXT

Patients with schizophrenia display abnormalities in pitch discrimination of non-verbal tones as revealed by the Tone-Matching Task (TMT). It may lead to deficits in higher-order cognitive functions and clinical symptoms.

OBJECTIVES

We conducted a systematic review and meta-analysis pooling data about TMT score differences between patients with schizophrenia and healthy controls, to evaluate the deficit's effect size, and to develop reliable knowledge about pitch processing impairment and its pejorative impact.

METHOD

Relevant publications were identified by a systematic search of PubMed and EMBASE databases. Then, we excluded non-relevant studies for the meta-analysis. Effect size for percent of correct responses to the TMT was expressed as standardized mean difference (SMD).

RESULTS

Eighteen of 167 identified studies met eligibility criteria for review, of which 10 were included in the meta-analysis. Our meta-analysis showed that the effect size for the percent of correct response to the TMT between patients (N=371) and controls (N=342) was large: SMD=1.17 [95% CI: 0.926-1.418] (z-value=9.338 and p-value<0.001). Meta-analysis showed moderate heterogeneity between studies (Q(9)=17.22, p=0.04, I²=47.74%). The relationship between tone-matching impairment and clinical symptoms of schizophrenia remains heterogeneous across studies. Some authors observed significant correlations between tone-matching performance and a number of higher-order cognitive abilities.

CONCLUSION

This review and meta-analysis highlights a large significant disturbance in tone-matching ability in patients as compared with controls. The study of basic auditory processing opens promising perspectives for pathophysiological modelling of the disorder and therapeutic issues.

An examination of the language construct in NIMH's research domain criteria: Time for reconceptualization!

The National Institute of Mental Health's Research Domain Criteria (RDoC) Initiative "calls for the development of new ways of classifying psychopathology based on dimensions of observable behavior." As a result of this ambitious initiative, language has been identified as an independent construct in the RDoC matrix. In this article, we frame language within an evolutionary and neuropsychological context and discuss some of the limitations to the current measurements of language. Findings from genomics and the neuroimaging of performance during language tasks are discussed in relation to serious mental illness and within the context of caveats regarding measuring language. Indeed, the data collection and analysis methods employed to assay language have been both aided and constrained by the available technologies, methodologies, and conceptual definitions. Consequently, different fields of language research show inconsistent definitions of language that have become increasingly broad over time. Individually, they have also shown significant improvements in conceptual resolution, as well as in experimental and analytic techniques. More recently, language research has embraced collaborations across disciplines, notably neuroscience, cognitive science, and computational linguistics and has ultimately re-defined classical ideas of language. As we move forward, the new models of language with their remarkably multifaceted constructs force a re-examination of the NIMH RDoC conceptualization of language and thus the neuroscience and genetics underlying this concept. © 2016 The Authors. American Journal of Medical Genetics Part B: Neuropsychiatric Genetics Published by Wiley Periodicals, Inc.

Mismatch Negativity to Threatening Voices Associated with Positive Symptoms in Schizophrenia

Although the general consensus holds that emotional perception is impaired in patients with schizophrenia, the extent to which neural processing of emotional voices is altered in schizophrenia remains to be determined. This study enrolled 30 patients with chronic schizophrenia and 30 controls and measured their mismatch negativity (MMN), a component of auditory event-related potentials (ERP). In a passive oddball paradigm, happily or angrily spoken deviant syllables dada were randomly presented within a train of emotionally neutral standard syllables. Results showed that MMN in response to angry syllables and angry-derived non-vocal sounds was significantly decreased in individuals with schizophrenia. P3a to angry syllables showed stronger amplitudes but longer latencies. Weaker MMN amplitudes were associated with more positive symptoms of schizophrenia. Receiver operator characteristic analysis revealed that angry MMN, angry-derived MMN, and angry P3a could help predict whether someone had received a clinical diagnosis of schizophrenia. The findings suggested general impairments of voice perception and acoustic discrimination in patients with chronic schizophrenia. The emotional salience processing of voices showed an atypical fashion at the preattentive level, being associated with positive symptoms in schizophrenia.

A Cognitive Neuroscience View of Voice-Processing Abnormalities in Schizophrenia: A Window into Auditory Verbal Hallucinations?

Auditory verbal hallucinations (AVH) are a core symptom of schizophrenia. Like "real" voices, AVH carry a rich amount of linguistic and paralinguistic cues that convey not only speech, but also affect and identity, information. Disturbed processing of voice identity, affective, and speech information has been reported in patients with schizophrenia. More recent evidence has suggested a link between voice-processing abnormalities and specific clinical symptoms of schizophrenia, especially AVH. It is still not well understood, however, to what extent these dimensions are impaired and how abnormalities in these processes might contribute to AVH. In this review, we consider behavioral, neuroimaging, and electrophysiological data to investigate the speech, identity, and affective dimensions of voice processing in schizophrenia, and we discuss how abnormalities in these processes might help to elucidate the mechanisms underlying specific phenomenological features of AVH. Schizophrenia patients exhibit behavioral and neural disturbances in the three dimensions of voice processing. Evidence suggesting a role of dysfunctional voice processing in AVH seems to be stronger for the identity and speech dimensions than for the affective domain.

Neural Substrates of Auditory Emotion Recognition Deficits in Schizophrenia

Deficits in auditory emotion recognition (AER) are a core feature of schizophrenia and a key component of social cognitive impairment. AER deficits are tied behaviorally to impaired ability to interpret tonal ("prosodic") features of speech that normally convey emotion, such as modulations in base pitch (F0M) and pitch variability (F0SD). These modulations can be recreated using synthetic frequency modulated (FM) tones that mimic the prosodic contours of specific emotional stimuli. The present study investigates neural mechanisms underlying impaired AER using a combined event-related potential/resting-state functional connectivity (rsfMRI) approach in 84 schizophrenia/schizoaffective disorder patients and 66 healthy comparison subjects. Mismatch negativity (MMN) to FM tones was assessed in 43 patients/36 controls. rsfMRI between auditory cortex and medial temporal (insula) regions was assessed in 55 patients/51 controls. The relationship between AER, MMN to FM tones, and rsfMRI was assessed in the subset who performed all assessments (14 patients, 21 controls). As predicted, patients showed robust reductions in MMN across FM stimulus type (p = 0.005), particularly to modulations in F0M, along with impairments in AER and FM tone discrimination. MMN source analysis indicated dipoles in both auditory cortex and anterior insula, whereas rsfMRI analyses showed reduced auditory-insula connectivity. MMN to FM tones and functional connectivity together accounted for ∼50% of the variance in AER performance across individuals. These findings demonstrate that impaired preattentive processing of tonal information and reduced auditory-insula connectivity are critical determinants of social cognitive dysfunction in schizophrenia, and thus represent key targets for future research and clinical intervention.

SIGNIFICANCE STATEMENT

Schizophrenia patients show deficits in the ability to infer emotion based upon tone of voice [auditory emotion recognition (AER)] that drive impairments in social cognition and global functional outcome. This study evaluated neural substrates of impaired AER in schizophrenia using a combined event-related potential/resting-state fMRI approach. Patients showed impaired mismatch negativity response to emotionally relevant frequency modulated tones along with impaired functional connectivity between auditory and medial temporal (anterior insula) cortex. These deficits contributed in parallel to impaired AER and accounted for ∼50% of variance in AER performance. Overall, these findings demonstrate the importance of both auditory-level dysfunction and impaired auditory/insula connectivity in the pathophysiology of social cognitive dysfunction in schizophrenia.

Social cognition in schizophrenia

Individuals with schizophrenia exhibit impaired social cognition, which manifests as difficulties in identifying emotions, feeing connected to others, inferring people's thoughts and reacting emotionally to others. These social cognitive impairments interfere with social connections and are strong determinants of the degree of impaired daily functioning in such individuals. Here, we review recent findings from the fields of social cognition and social neuroscience and identify the social processes that are impaired in schizophrenia. We also consider empathy as an example of a complex social cognitive function that integrates several social processes and is impaired in schizophrenia. This information may guide interventions to improve social cognition in patients with this disorder.

Neural responses to dynamic multimodal stimuli and pathology-specific impairments of social cognition in schizophrenia and depression

BACKGROUND

Individuals with schizophrenia and people with depression both show abnormal behavioural and neural responses when perceiving and responding to emotional stimuli, but pathology-specific differences and commonalities remain mostly unclear.

AIMS

To directly compare empathic responses to dynamic multimodal emotional stimuli in a group with schizophrenia and a group with depression, and to investigate their neural correlates using functional magnetic resonance imaging (fMRI).

METHOD

The schizophrenia group (n = 20), the depression group (n = 24) and a control group (n = 24) were presented with portrait-shot video clips expressing emotion through three possible communication channels: facial expression, prosody and content. Participants rated their own and the actor's emotional state as an index of empathy.

RESULTS

Although no group differences were found in empathy ratings, characteristic differences emerged in the fMRI activation patterns. The schizophrenia group demonstrated aberrant activation patterns during the neutral speech content condition in regions implicated in multimodal integration and formation of semantic constructs. Those in the depression group were most affected during conditions with trimodal emotional and trimodal neutral stimuli, in key regions of the mentalising network.

CONCLUSIONS

Our findings reveal characteristic differences in patients with schizophrenia compared with those with depression in their cortical responses to dynamic affective stimuli. These differences indicate that impairments in responding to emotional stimuli may be caused by pathology-specific problems in social cognition.

The music of language: an ERP investigation of the effects of musical training on emotional prosody processing

Recent studies have demonstrated the positive effects of musical training on the perception of vocally expressed emotion. This study investigated the effects of musical training on event-related potential (ERP) correlates of emotional prosody processing. Fourteen musicians and fourteen control subjects listened to 228 sentences with neutral semantic content, differing in prosody (one third with neutral, one third with happy and one third with angry intonation), with intelligible semantic content (semantic content condition--SCC) and unintelligible semantic content (pure prosody condition--PPC). Reduced P50 amplitude was found in musicians. A difference between SCC and PPC conditions was found in P50 and N100 amplitude in non-musicians only, and in P200 amplitude in musicians only. Furthermore, musicians were more accurate in recognizing angry prosody in PPC sentences. These findings suggest that auditory expertise characterizing extensive musical training may impact different stages of vocal emotional processing.

Auditory tasks for assessment of sensory function and affective prosody in schizophrenia

Schizophrenia patients exhibit impairments in auditory-based social cognition, indicated by deficits in detection of prosody, such as affective prosody and basic pitch perception. However, little is known about the psychometric properties of behavioral tests used to assess these functions. The goal of this paper is to characterize the properties of prosody and pitch perception tasks and to investigate whether they can be shortened. The pitch perception test evaluated is a tone-matching task developed by Javitt and colleagues (J-TMT). The prosody test evaluated is the auditory emotion recognition task developed by Juslin and Laukka (JL-AER). The sample includes 124 schizophrenia patients (SZ) and 131 healthy controls (HC). Properties, including facility and discrimination, of each item were assessed. Effects of item characteristics (e.g., emotion) were also evaluated. Shortened versions of the tests are proposed based on facility, discrimination, and/or ability of item characteristics to discriminate between patients and controls. Test-retest reliability is high for patients and controls for both the original and short forms of the J-TMT and JL-AER. Thus, the original as well as short forms of the J-TMT and JL-AER are suggested for inclusion in clinical trials of social cognitive and perceptual treatments. The development of short forms further increases the utility of these auditory tasks in clinical trials and clinical practice. The large SZ vs. HC differences reported here also highlight the profound nature of auditory deficits and a need for remediation.

The role of the medial temporal limbic system in processing emotions in voice and music

Subcortical brain structures of the limbic system, such as the amygdala, are thought to decode the emotional value of sensory information. Recent neuroimaging studies, as well as lesion studies in patients, have shown that the amygdala is sensitive to emotions in voice and music. Similarly, the hippocampus, another part of the temporal limbic system (TLS), is responsive to vocal and musical emotions, but its specific roles in emotional processing from music and especially from voices have been largely neglected. Here we review recent research on vocal and musical emotions, and outline commonalities and differences in the neural processing of emotions in the TLS in terms of emotional valence, emotional intensity and arousal, as well as in terms of acoustic and structural features of voices and music. We summarize the findings in a neural framework including several subcortical and cortical functional pathways between the auditory system and the TLS. This framework proposes that some vocal expressions might already receive a fast emotional evaluation via a subcortical pathway to the amygdala, whereas cortical pathways to the TLS are thought to be equally used for vocal and musical emotions. While the amygdala might be specifically involved in a coarse decoding of the emotional value of voices and music, the hippocampus might process more complex vocal and musical emotions, and might have an important role especially for the decoding of musical emotions by providing memory-based and contextual associations.

Biases in facial and vocal emotion recognition in chronic schizophrenia

There has been extensive research on impaired emotion recognition in schizophrenia in the facial and vocal modalities. The literature points to biases toward non-relevant emotions for emotional faces but few studies have examined biases in emotional recognition across different modalities (facial and vocal). In order to test emotion recognition biases, we exposed 23 patients with stabilized chronic schizophrenia and 23 healthy controls (HCs) to emotional facial and vocal tasks asking them to rate emotional intensity on visual analog scales. We showed that patients with schizophrenia provided higher intensity ratings on the non-target scales (e.g., surprise scale for fear stimuli) than HCs for the both tasks. Furthermore, with the exception of neutral vocal stimuli, they provided the same intensity ratings on the target scales as the HCs. These findings suggest that patients with chronic schizophrenia have emotional biases when judging emotional stimuli in the visual and vocal modalities. These biases may stem from a basic sensorial deficit, a high-order cognitive dysfunction, or both. The respective roles of prefrontal-subcortical circuitry and the basal ganglia are discussed.

Hallucinations and negative symptoms differentially revealed by frontal and temporal responses to speech in schizophrenia

BACKGROUND

Auditory verbal hallucinations (AVH) in schizophrenia may arise because of aberrant speech perception. We used an electroencephalography method to examine the neural processes underlying speech perception in schizophrenic patients with hallucinations.

METHODS

Cortical event-related potentials (ERPs) were analyzed topographically (scalp potential and scalp current density (SCD) mapping) in response to the vowel /a/ using a passive paradigm in 26 patients with schizophrenia.

RESULTS

From the SCD distribution of the P1 peak, we showed that, whereas the hallucination score (PSYRATS) was negatively correlated with the amplitude of the frontal currents, the PANSS negative symptom score was negatively correlated with the amplitude of the temporal currents in patients with schizophrenia.

CONCLUSIONS

These results provide evidence that AVH and negative symptoms are associated with abnormal early processing of speech. Whereas AVH are related to decreased early frontal activation, negative symptoms are associated with a reduced early temporal response.

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

BACKGROUND

Abnormalities 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.

METHOD

We 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).

RESULTS

Relative 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.

CONCLUSIONS

Together, 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.

The 5% difference: early sensory processing predicts sarcasm perception in schizophrenia and schizo-affective disorder

BACKGROUND

Intact sarcasm perception is a crucial component of social cognition and mentalizing (the ability to understand the mental state of oneself and others). In sarcasm, tone of voice is used to negate the literal meaning of an utterance. In particular, changes in pitch are used to distinguish between sincere and sarcastic utterances. Schizophrenia patients show well-replicated deficits in auditory function and functional connectivity (FC) within and between auditory cortical regions. In this study we investigated the contributions of auditory deficits to sarcasm perception in schizophrenia.

METHOD

Auditory measures including pitch processing, auditory emotion recognition (AER) and sarcasm detection were obtained from 76 patients with schizophrenia/schizo-affective disorder and 72 controls. Resting-state FC (rsFC) was obtained from a subsample and was analyzed using seeds placed in both auditory cortex and meta-analysis-defined core-mentalizing regions relative to auditory performance.

RESULTS

Patients showed large effect-size deficits across auditory measures. Sarcasm deficits correlated significantly with general functioning and impaired pitch processing both across groups and within the patient group alone. Patients also showed reduced sensitivity to alterations in mean pitch and variability. For patients, sarcasm discrimination correlated exclusively with the level of rsFC within primary auditory regions whereas for controls, correlations were observed exclusively within core-mentalizing regions (the right posterior superior temporal gyrus, anterior superior temporal sulcus and insula, and left posterior medial temporal gyrus).

CONCLUSIONS

These findings confirm the contribution of auditory deficits to theory of mind (ToM) impairments in schizophrenia, and demonstrate that FC within auditory, but not core-mentalizing, regions is rate limiting with respect to sarcasm detection in schizophrenia.

The building blocks of social communication

In the present review, social communication will be discussed in the context of social cognition, and cold and hot cognition. The review presents research on prosody, processing of faces, multimodal processing of voice and face, and the impact of emotion on constructing semantic meaning. Since the focus of this mini review is on brain processes involved in these cognitive functions, the bulk of evidence presented will be from event related potential (ERP) studies as this methodology offers the best temporal resolution of cognitive events under study. The argument is made that social communication is accomplished via fast acting sensory processes and later, top down processes. Future directions both in terms of methodology and research questions are also discussed.

Isn't it ironic? Neural correlates of irony comprehension in schizophrenia

Ironic remarks are frequent in everyday language and represent an important form of social cognition. Increasing evidence indicates a deficit in comprehension in schizophrenia. Several models for defective comprehension have been proposed, including possible roles of the medial prefrontal lobe, default mode network, inferior frontal gyri, mirror neurons, right cerebral hemisphere and a possible mediating role of schizotypal personality traits. We investigated the neural correlates of irony comprehension in schizophrenia by using event-related functional magnetic resonance imaging (fMRI). In a prosody-free reading paradigm, 15 female patients with schizophrenia and 15 healthy female controls silently read ironic and literal text vignettes during fMRI. Each text vignette ended in either an ironic (n = 22) or literal (n = 22) statement. Ironic and literal text vignettes were matched for word frequency, length, grammatical complexity, and syntax. After fMRI, the subjects performed an off-line test to detect error rate. In this test, the subjects indicated by button press whether the target sentence has ironic, literal, or meaningless content. Schizotypal personality traits were assessed using the German version of the schizotypal personality questionnaire (SPQ). Patients with schizophrenia made significantly more errors than did the controls (correct answers, 85.3% vs. 96.3%) on a behavioural level. Patients showed attenuated blood oxygen level-dependent (BOLD) response during irony comprehension mainly in right hemisphere temporal regions (ironic>literal contrast) and in posterior medial prefrontal and left anterior insula regions (for ironic>visual baseline, but not for literal>visual baseline). In patients with schizophrenia, the parahippocampal gyrus showed increased activation. Across all subjects, BOLD response in the medial prefrontal area was negatively correlated with the SPQ score. These results highlight the role of the posterior medial prefrontal and right temporal regions in defective irony comprehension in schizophrenia and the mediating role of schizotypal personality traits.

Gray matter abnormalities in schizophrenia patients with tardive dyskinesia: a magnetic resonance imaging voxel-based morphometry study

OBJECTIVE

The pathophysiological mechanism of TD remains unknown. All previous studies, using the region-of-interest method, focused on basal ganglion areas, were with inconsistent results. This whole-brain voxel-based morphometry (VBM) study investigate the grey matter abnormality of TD and its correlates with clinical ratings.

METHOD

High resolution T1-weighted brain volumetric MRI from 25 schizophrenia patients with TD (TD group), 25 age-, gender-, and handedness-matched schizophrenia patients without TD (non-TD group), and 25 matched healthy subjects (NC group) were analyzed using a VBM approach. Clinical ratings included the Positive and Negative Symptom Scale (PANSS), Abnormal Involuntary Movement Scale (AIMS), and the Simpson-Angus Scale (SAS).

RESULTS

The TD group had significantly smaller total gray matter volumes than the NC group (p = 0.05). Compared to the non-TD group, the TD group had significantly higher PANSS negative (p<0.001), SAS (p<0.001), and AIMS (p<0.001) scores; and smaller bilateral inferior frontal gyrus, which correlated negatively with the PANSS negative scores (r = -0.366, p<0.05); and smaller right superior frontal gyrus, which correlated negatively with AIMS scores (r = -0.399, p<0.001), and PANSS general score (r = -0.338, p<0.05).

LIMITATIONS

The cross-section design can't separate the gray matter change to TD from the context of the illness of schizophrenia, although TD with more severe clinical psychopathology could be a phenotype.

CONCLUSIONS

The schizophrenia patients with TD had significantly reduced gray matter, mostly at the bilateral inferior frontal gyrus and the right superior frontal gyrus, which correlated with severity of clinical symptoms and involuntary movement, respectively.

Cerebral responses to vocal attractiveness and auditory hallucinations in schizophrenia: a functional MRI study

Impaired self-monitoring and abnormalities of cognitive bias have been implicated as cognitive mechanisms of hallucination; regions fundamental to these processes including inferior frontal gyrus (IFG) and superior temporal gyrus (STG) are abnormally activated in individuals that hallucinate. A recent study showed activation in IFG-STG to be modulated by auditory attractiveness, but no study has investigated whether these IFG-STG activations are impaired in schizophrenia. We aimed to clarify the cerebral function underlying the perception of auditory attractiveness in schizophrenia patients. Cerebral activation was examined in 18 schizophrenia patients and 18 controls when performing Favorability Judgment Task (FJT) and Gender Differentiation Task (GDT) for pairs of greetings using event-related functional MRI. A full-factorial analysis revealed that the main effect of task was associated with activation of left IFG and STG. The main effect of Group revealed less activation of left STG in schizophrenia compared with controls, whereas significantly greater activation in schizophrenia than in controls was revealed at the left middle frontal gyrus (MFG), right temporo-parietal junction (TPJ), right occipital lobe, and right amygdala (p < 0.05, FDR-corrected). A significant positive correlation was observed at the right TPJ and right MFG between cerebral activation under FJT minus GDT contrast and the score of hallucinatory behavior on the Positive and Negative Symptom Scale. Findings of hypo-activation in the left STG could designate brain dysfunction in accessing vocal attractiveness in schizophrenia, whereas hyper-activation in the right TPJ and MFG may reflect the process of mentalizing other person's behavior by auditory hallucination by abnormality of cognitive bias.

Voices to reckon with: perceptions of voice identity in clinical and non-clinical voice hearers

The current review focuses on the perception of voice identity in clinical and non-clinical voice hearers. Identity perception in auditory verbal hallucinations (AVH) is grounded in the mechanisms of human (i.e., real, external) voice perception, and shapes the emotional (distress) and behavioral (help-seeking) response to the experience. Yet, the phenomenological assessment of voice identity is often limited, for example to the gender of the voice, and has failed to take advantage of recent models and evidence on human voice perception. In this paper we aim to synthesize the literature on identity in real and hallucinated voices and begin by providing a comprehensive overview of the features used to judge voice identity in healthy individuals and in people with schizophrenia. The findings suggest some subtle, but possibly systematic biases across different levels of voice identity in clinical hallucinators that are associated with higher levels of distress. Next we provide a critical evaluation of voice processing abilities in clinical and non-clinical voice hearers, including recent data collected in our laboratory. Our studies used diverse methods, assessing recognition and binding of words and voices in memory as well as multidimensional scaling of voice dissimilarity judgments. The findings overall point to significant difficulties recognizing familiar speakers and discriminating between unfamiliar speakers in people with schizophrenia, both with and without AVH. In contrast, these voice processing abilities appear to be generally intact in non-clinical hallucinators. The review highlights some important avenues for future research and treatment of AVH associated with a need for care, and suggests some novel insights into other symptoms of psychosis.

Emotional prosody modulates attention in schizophrenia patients with hallucinations

Recent findings have demonstrated that emotional prosody (EP) attracts attention involuntarily (Grandjean et al., 2008). The automat shift of attention toward emotionally salient stimuli can be overcome by attentional control (Hahn et al., 2010). Attentional control is impaired in schizophrenia, especially in schizophrenic patients with hallucinations because the "voices" capture attention increasing the processing load and competing for top-down resources. The present study investigates how involuntary attention is driven by implicit EP in schizophrenia with auditory verbal hallucinations (AVH) and without (NAVH). Fifteen AVH patients, 12 NAVH patients and 16 healthy controls (HC) completed a dual-task dichotic listening paradigm, in which an emotional vocal outburst was paired with a neutral vocalization spoken in male and female voices. Participants were asked to report the speaker's gender while attending to either the left or right ear. NAVH patients and HC revealed shorter response times for stimuli presented to the attended left ear than the attended right ear. This laterality effect was not present in AVH patients. In addition, NAVH patients and HC showed faster responses when the EP stimulus was presented to the unattended ear, probably because of less interference between the attention-controlled gender voice identification task and involuntary EP processing. AVH patients did not benefit from presenting emotional stimuli to the unattended ear. The findings suggest that similar to HC, NAVH patients show a right hemispheric bias for EP processing. AVH patients seem to be less lateralized for EP and therefore might be more susceptible to interfering involuntary EP processing; regardless which ear/hemisphere receives the bottom up input.

Sensory-based and higher-order operations contribute to abnormal emotional prosody processing in schizophrenia: an electrophysiological investigation

BACKGROUND

Schizophrenia is characterized by deficits in emotional prosody (EP) perception. However, it is not clear which stages of processing prosody are abnormal and whether the presence of semantic content contributes to the abnormality. This study aimed to examine event-related potential (ERP) correlates of EP processing in 15 chronic schizophrenia individuals and 15 healthy controls.

METHOD

A total of 114 sentences with neutral semantic content [sentences with semantic content (SSC) condition] were generated by a female speaker (38 with happy, 38 with angry, and 38 with neutral intonation). The same sentences were synthesized and presented in the 'pure prosody' sentences (PPS) condition where semantic content was unintelligible.

RESULTS

Group differences were observed for N100 and P200 amplitude: patients were characterized by more negative N100 for SSC, and more positive P200 for angry and happy SSC and happy PPS. Correlations were found between delusions and P200 amplitude for happy SSC and PPS. Higher error rates in the recognition of EP were also observed in schizophrenia: higher error rates in neutral SSC were associated with reduced N100, and higher error rates in angry SSC were associated with reduced P200.

CONCLUSIONS

These results indicate that abnormalities in prosody processing occur at the three stages of EP processing, and are enhanced in SSC. Correlations between P200 amplitude for happy prosody and delusions suggest a role that abnormalities in the processing of emotionally salient acoustic cues may play in schizophrenia symptomatology. Correlations between ERP and behavioral data point to a relationship between early sensory abnormalities and prosody recognition in schizophrenia.

Comparison of psychophysical, electrophysiological, and fMRI assessment of visual contrast responses in patients with schizophrenia

Perception has been identified by the NIMH-sponsored Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) group as a useful domain for assessing cognitive deficits in patients with schizophrenia. Specific measures of contrast gain derived from recordings of steady-state visual evoked potentials (ssVEP) have demonstrated neural deficits within the visual pathways of patients with schizophrenia. Psychophysical measures of contrast sensitivity have also shown functional loss in these patients. In the current study, functional magnetic resonance imaging (fMRI) was used in conjunction with ssVEP and contrast sensitivity testing to elucidate the neural underpinnings of these deficits. During fMRI scanning, participants viewed 1) the same low and higher spatial frequency stimuli used in the psychophysical contrast sensitivity task, at both individual detection threshold contrast and at a high contrast; and 2) the same stimuli used in the ssVEP paradigm, which were designed to be biased toward either the magnocellular or parvocellular visual pathway. Patients showed significant impairment in contrast sensitivity at both spatial frequencies in the psychophysical task, but showed reduced occipital activation volume for low, but not higher, spatial frequency at the low and high contrasts tested in the magnet. As expected, patients exhibited selective deficits under the magnocellular-biased ssVEP condition. However, occipital lobe fMRI responses demonstrated the same general pattern for magnocellular- and parvocellular-biased stimuli across groups. These results indicate dissociation between the fMRI measures and the psychophysical/ssVEP measures. These latter measures appear to have greater value for the functional assessment of the contrast deficits explored here.

Relationship between auditory processing and affective prosody in schizophrenia

Patients with schizophrenia have well-established deficits in their ability to identify emotion from facial expression and tone of voice. In the visual modality, there is strong evidence that basic processing deficits contribute to impaired facial affect recognition in schizophrenia. However, few studies have examined the auditory modality for mechanisms underlying affective prosody identification. In this study, we explored links between different stages of auditory processing, using event-related potentials (ERPs), and affective prosody detection in schizophrenia. Thirty-six schizophrenia patients and 18 healthy control subjects received tasks of affective prosody, facial emotion identification, and tone matching, as well as two auditory oddball paradigms, one passive for mismatch negativity (MMN) and one active for P300. Patients had significantly reduced MMN and P300 amplitudes, impaired auditory and visual emotion recognition, and poorer tone matching performance, relative to healthy controls. Correlations between ERP and behavioral measures within the patient group revealed significant associations between affective prosody recognition and both MMN and P300 amplitudes. These relationships were modality specific, as MMN and P300 did not correlate with facial emotion recognition. The two ERP waves accounted for 49% of the variance in affective prosody in a regression analysis. Our results support previous suggestions of a relationship between basic auditory processing abnormalities and affective prosody dysfunction in schizophrenia, and indicate that both relatively automatic pre-attentive processes (MMN) and later attention-dependent processes (P300) are involved with accurate auditory emotion identification. These findings provide support for bottom-up (e.g., perceptually based) cognitive remediation approaches.

Cognitive and neuroplasticity mechanisms by which congenital or early blindness may confer a protective effect against schizophrenia

Several authors have noted that there are no reported cases of people with schizophrenia who were born blind or who developed blindness shortly after birth, suggesting that congenital or early (C/E) blindness may serve as a protective factor against schizophrenia. By what mechanisms might this effect operate? Here, we hypothesize that C/E blindness offers protection by strengthening cognitive functions whose impairment characterizes schizophrenia, and by constraining cognitive processes that exhibit excessive flexibility in schizophrenia. After briefly summarizing evidence that schizophrenia is fundamentally a cognitive disorder, we review areas of perceptual and cognitive function that are both impaired in the illness and augmented in C/E blindness, as compared to healthy sighted individuals. We next discuss: (1) the role of neuroplasticity in driving these cognitive changes in C/E blindness; (2) evidence that C/E blindness does not confer protective effects against other mental disorders; and (3) evidence that other forms of C/E sensory loss (e.g., deafness) do not reduce the risk of schizophrenia. We conclude by discussing implications of these data for designing cognitive training interventions to reduce schizophrenia-related cognitive impairment, and perhaps to reduce the likelihood of the development of the disorder itself.

Prosodic abnormalities in schizotypal personality disorder

OBJECTIVE

Patients with schizophrenia speak with blunted vocal affect but little is known regarding the prosody of persons with schizotypal personality disorder (SPD). This work examined expressive prosody in SPD, its relationship to brain structure, and outlined a framework for measuring elements of prosody in clinical populations.

METHODS

Twenty-eight antipsychotic-naïve SPD subjects were matched with 27 healthy comparison (HC) subjects. Subjects read aloud short sentences and responded to probes to record both predetermined and self-generated speech samples. Samples were analyzed acoustically (pause proportion, duration, attack, and pitch variability) and subjectively by raters (amount of pauses, degree of emotion portrayed, and how much they wanted to hear more from the subjects) on paragraph, sentence, word, word-fragment, and syllable levels. Alexithymia and ability to self-monitor behavior were compared between groups. The pars opercularis was manually traced on structural MRI data.

RESULTS

SPD subjects' speech had significantly more pauses, was slower, had less pitch variability, and expressed less emotion than HC subjects. Pitch variability correlated with socio-economic status achievement. There was no difference between groups in left or right pars opercularis volumes. A statistically significant correlation suggested that smaller left pars opercularis volumes in SPD subjects correlated with more pauses and less emotion. SPD subjects reported more alexithymia and difficulty self-monitoring their behavior compared with controls. In SPD subjects the high alexithymia correlated with raters not wanting to hear more from them and SPD subjects' inability to modulate their social behavior correlated with their having fewer friends. Thus, the SPD subjects exhibited insight.

CONCLUSIONS

SPD subjects displayed significant prosodic deficits that were measurable in speech samples as brief as a word-fragment. The determinants of these deficits are not known although these may include a dysfunctional pars opercularis. These data add to the nascent literature describing social cognition deficits in SPD.

Voice identity recognition failure in patients with schizophrenia

Cognitive models propose that auditory verbal hallucinations arise through inner speech misidentification. However, such models cannot explain why the voices in hallucinations often have identities different from the hearer. This study investigated whether a general voice identity recognition difficulty might be present in schizophrenia and related to auditory verbal hallucinations. Twenty-five schizophrenia patients and 13 healthy controls were tested on recognition of famous voices. Signal detection theory was used to calculate perceptual sensitivity and response criterion measures. Schizophrenia patients obtained fewer hits and had lower perceptual sensitivity to detect famous voices than healthy controls did. There were no differences between groups in false alarm rate or response criterion. A symptom-based analysis demonstrated that especially those patients with auditory verbal hallucinations performed poorly in the task. The results indicate that patients with hallucinations are impaired at voice identity recognition because of decreased sensitivity, which may result in inner speech misidentification.

Contributions of low and high spatial frequency processing to impaired object recognition circuitry in schizophrenia

Patients with schizophrenia exhibit cognitive and sensory impairment, and object recognition deficits have been linked to sensory deficits. The "frame and fill" model of object recognition posits that low spatial frequency (LSF) information rapidly reaches the prefrontal cortex (PFC) and creates a general shape of an object that feeds back to the ventral temporal cortex to assist object recognition. Visual dysfunction findings in schizophrenia suggest a preferential loss of LSF information. This study used functional magnetic resonance imaging (fMRI) and resting state functional connectivity (RSFC) to investigate the contribution of visual deficits to impaired object "framing" circuitry in schizophrenia. Participants were shown object stimuli that were intact or contained only LSF or high spatial frequency (HSF) information. For controls, fMRI revealed preferential activation to LSF information in precuneus, superior temporal, and medial and dorsolateral PFC areas, whereas patients showed a preference for HSF information or no preference. RSFC revealed a lack of connectivity between early visual areas and PFC for patients. These results demonstrate impaired processing of LSF information during object recognition in schizophrenia, with patients instead displaying increased processing of HSF information. This is consistent with findings of a preference for local over global visual information in schizophrenia.

Auditory emotion recognition impairments in schizophrenia: relationship to acoustic features and cognition

OBJECTIVE

Schizophrenia is associated with deficits in the ability to perceive emotion based on tone of voice. The basis for this deficit remains unclear, however, and relevant assessment batteries remain limited. The authors evaluated performance in schizophrenia on a novel voice emotion recognition battery with well-characterized physical features, relative to impairments in more general emotional and cognitive functioning.

METHOD

The authors studied a primary sample of 92 patients and 73 comparison subjects. Stimuli were characterized according to both intended emotion and acoustic features (e.g., pitch, intensity) that contributed to the emotional percept. Parallel measures of visual emotion recognition, pitch perception, general cognition, and overall outcome were obtained. More limited measures were obtained in an independent replication sample of 36 patients, 31 age-matched comparison subjects, and 188 general comparison subjects.

RESULTS

Patients showed statistically significant large-effect-size deficits in voice emotion recognition (d=1.1) and were preferentially impaired in recognition of emotion based on pitch features but not intensity features. Emotion recognition deficits were significantly correlated with pitch perception impairments both across (r=0.56) and within (r=0.47) groups. Path analysis showed both sensory-specific and general cognitive contributions to auditory emotion recognition deficits in schizophrenia. Similar patterns of results were observed in the replication sample.

CONCLUSIONS

The results demonstrate that patients with schizophrenia show a significant deficit in the ability to recognize emotion based on tone of voice and that this deficit is related to impairment in detecting the underlying acoustic features, such as change in pitch, required for auditory emotion recognition. This study provides tools for, and highlights the need for, greater attention to physical features of stimuli used in studying social cognition in neuropsychiatric disorders.

The neural correlates of emotional prosody comprehension: disentangling simple from complex emotion

Background

Emotional prosody comprehension (EPC), the ability to interpret another person's feelings by listening to their tone of voice, is crucial for effective social communication. Previous studies assessing the neural correlates of EPC have found inconsistent results, particularly regarding the involvement of the medial prefrontal cortex (mPFC). It remained unclear whether the involvement of the mPFC is linked to an increased demand in socio-cognitive components of EPC such as mental state attribution and if basic perceptual processing of EPC can be performed without the contribution of this region.

Methods

fMRI was used to delineate neural activity during the perception of prosodic stimuli conveying simple and complex emotion. Emotional trials in general, as compared to neutral ones, activated a network comprising temporal and lateral frontal brain regions, while complex emotion trials specifically showed an additional involvement of the mPFC, premotor cortex, frontal operculum and left insula.

Conclusion

These results indicate that the mPFC and premotor areas might be associated, but are not crucial to EPC. However, the mPFC supports socio-cognitive skills necessary to interpret complex emotion such as inferring mental states. Additionally, the premotor cortex involvement may reflect the participation of the mirror neuron system for prosody processing particularly of complex emotion.