Assessing Trial-to-Trial Variability in Auditory ERPs in Autism and Schizophrenia.

Sensory abnormalities are characteristic of autism and schizophrenia. In autism, greater trial-to-trial variability (TTV) in sensory neural responses suggest that the system is more unstable. However, these findings have only been identified in the amplitude and not in the timing of neural responses, and have not been fully explored in schizophrenia. TTV in event-related potential amplitudes and inter-trial coherence (ITC) were assessed in the auditory mismatch negativity (MMN) in autism, schizophrenia, and controls. MMN was largest in autism and smallest in schizophrenia, and TTV was greater in autism and schizophrenia compared to controls. There were no differences in ITC. Greater TTV appears to be characteristic of both autism and schizophrenia, implicating several neural mechanisms that could underlie sensory instability.

Hyper-Sensitivity to Pitch and Poorer Prosody Processing in Adults With Autism: An ERP Study.

Individuals with autism typically experience a range of symptoms, including abnormal sensory sensitivities. However, there are conflicting reports on the sensory profiles that characterize the sensory experience in autism that often depend on the type of stimulus. Here, we examine early auditory processing to simple changes in pitch and later auditory processing of more complex emotional utterances. We measured electroencephalography in 24 adults with autism and 28 controls. First, tones (1046.5Hz/C6, 1108.7Hz/C#6, or 1244.5Hz/D#6) were repeated three times or nine times before the pitch changed. Second, utterances of delight or frustration were repeated three or six times before the emotion changed. In response to the simple pitched tones, the autism group exhibited larger mismatch negativity (MMN) after nine standards compared to controls and produced greater trial-to-trial variability (TTV). In response to the prosodic utterances, the autism group showed smaller P3 responses when delight changed to frustration compared to controls. There was no significant correlation between ERPs to pitch and ERPs to prosody. Together, this suggests that early auditory processing is hyper-sensitive in autism whereas later processing of prosodic information is hypo-sensitive. The impact the different sensory profiles have on perceptual experience in autism may be key to identifying behavioral treatments to reduce symptoms.

Are basic auditory processes involved in source-monitoring deficits in patients with schizophrenia?

Patients with schizophrenia (SZ) display deficits in both basic non-verbal auditory processing and source-monitoring of speech. To date, the contributions of basic auditory deficits to higher-order cognitive impairments, such as source-monitoring, and to clinical symptoms have yet to be elucidated. The aim of this study was to investigate the deficits and relationships between basic auditory functions, source-monitoring performances, and clinical symptom severity in SZ. Auditory processing of 4 psychoacoustic features (pitch, intensity, amplitude, length) and 2 types of source-monitoring (internal and reality monitoring) performances were assessed in 29 SZ and 29 healthy controls. Clinical symptoms were evaluated in patients with the Positive And Negative Syndrome Scale. Compared to the controls, SZ individuals in showed significant reductions in both global basic auditory processing (p < .0005, d = 1.16) and source-monitoring (p < .0005, d = 1.24) abilities. Both deficits correlated significantly in patients and across groups (all p < .05). Pitch processing skills were negatively correlated with positive symptom severity (r = -0.4, p < .05). A step-wise regression analysis showed that pitch discrimination was a significant predictor of source-monitoring performance. These results suggest that cognitive mechanisms associated with the discrimination of basic auditory features are most compromised in patients with source-monitoring disability. Basic auditory processing may index pathophysiological processes that are critical for optimal source-monitoring in schizophrenia and that are involved in positive symptoms.

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.

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.

Predictive suppression of cortical excitability and its deficit in schizophrenia.

Recent neuroscience advances suggest that when interacting with our environment, along with previous experience, we use contextual cues and regularities to form predictions that guide our perceptions and actions. The goal of such active "predictive sensing" is to selectively enhance the processing and representation of behaviorally relevant information in an efficient manner. Since a hallmark of schizophrenia is impaired information selection, we tested whether this deficiency stems from dysfunctional predictive sensing by measuring the degree to which neuronal activity predicts relevant events. In healthy subjects, we established that these mechanisms are engaged in an effort-dependent manner and that, based on a correspondence between human scalp and intracranial nonhuman primate recordings, their main role is a predictive suppression of excitability in task-irrelevant regions. In contrast, schizophrenia patients displayed a reduced alignment of neuronal activity to attended stimuli, which correlated with their behavioral performance deficits and clinical symptoms. These results support the relevance of predictive sensing for normal and aberrant brain function, and highlight the importance of neuronal mechanisms that mold internal ongoing neuronal activity to model key features of the external environment.

Reduction in tonal discriminations predicts receptive emotion processing deficits in schizophrenia and schizoaffective disorder.

INTRODUCTION: Schizophrenia patients show decreased ability to identify emotion based upon tone of voice (voice emotion recognition), along with deficits in basic auditory processing. Interrelationship among these measures is poorly understood. METHODS: Forty-one patients with schizophrenia/schizoaffective disorder and 41 controls were asked to identify the emotional valence (happy, sad, angry, fear, or neutral) of 38 synthesized frequency-modulated (FM) tones designed to mimic key acoustic features of human vocal expressions. The mean (F0M) and variability (F0SD) of fundamental frequency (pitch) and absence or presence of high frequency energy (HF500) of the tones were independently manipulated to assess contributions on emotion identification. Forty patients and 39 controls also completed tone-matching and voice emotion recognition tasks. RESULTS: Both groups showed a nonrandom response pattern (P < .0001). Stimuli with highest and lowest F0M/F0SD were preferentially identified as happy and sad, respectively. Stimuli with low F0M and midrange F0SD values were identified as angry. Addition of HF500 increased rates of angry and decreased rates of sad identifications. Patients showed less differentiation of response across frequency changes, leading to a highly significant between-group difference in response pattern to maximally identifiable stimuli (d = 1.4). The differential identification pattern for FM tones correlated with deficits in basic tone-matching ability (P = .01), voice emotion recognition (P < .001), and negative symptoms (P < .001). CONCLUSIONS: Specific FM tones conveyed reliable emotional percepts in both patients and controls and correlated highly with deficits in ability to recognize information based upon tone of voice, suggesting significant bottom-up contributions to social cognition and negative symptom impairments 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.

Preliminary Evidence of Pre-Attentive Distinctions of Frequency-Modulated Tones that Convey Affect.

Recognizing emotion is an evolutionary imperative. An early stage of auditory scene analysis involves the perceptual grouping of acoustic features, which can be based on both temporal coincidence and spectral features such as perceived pitch. Perceived pitch, or fundamental frequency (F(0)), is an especially salient cue for differentiating affective intent through speech intonation (prosody). We hypothesized that: (1) simple frequency-modulated tone abstractions, based on the parameters of actual prosodic stimuli, would be reliably classified as representing differing emotional categories; and (2) that such differences would yield significant mismatch negativities (MMNs) - an index of pre-attentive deviance detection within the auditory environment. We constructed a set of FM tones that approximated the F(0) mean and variation of reliably recognized happy and neutral prosodic stimuli. These stimuli were presented to 13 subjects using a passive listening oddball paradigm. We additionally included stimuli with no frequency modulation (FM) and FM tones with identical carrier frequencies but differing modulation depths as control conditions. Following electrophysiological recording, subjects were asked to identify the sounds they heard as happy, sad, angry, or neutral. We observed that FM tones abstracted from happy and no-expression speech stimuli elicited MMNs. Post hoc behavioral testing revealed that subjects reliably identified the FM tones in a consistent manner. Finally, we also observed that FM tones and no-FM tones elicited equivalent MMNs. MMNs to FM tones that differentiate affect suggests that these abstractions may be sufficient to characterize prosodic distinctions, and that these distinctions can be represented in pre-attentive auditory sensory memory.

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

BACKGROUND: Schizophrenia patients have vocal affect (prosody) deficits that are treatment resistant and associated with negative symptoms and poor outcome. The neural correlates of this dysfunction are unclear. Prior study has suggested that schizophrenia vocal affect perception deficits stem from an inability to use acoustic cues, notably pitch, in decoding emotion. METHODS: Functional magnetic resonance imaging was performed in 24 schizophrenia patients and 28 healthy control subjects, during the performance of a four-choice (happiness, fear, anger, neutral) vocal affect identification task in which items for each emotion varied parametrically in affective salient acoustic cue levels. RESULTS: We observed that parametric increases in cue levels in schizophrenia failed to produce the same identification rate increases as in control subjects. These deficits correlated with diminished reciprocal activation changes in superior temporal and inferior frontal gyri and reduced temporo-frontal connectivity. Task activation also correlated with independent measures of pitch perception and negative symptom severity. CONCLUSIONS: These findings illustrate the interplay between sensory and higher-order cognitive dysfunction in schizophrenia. Sensory contributions to vocal affect deficits also suggest that this neurobehavioral marker could be targeted by pharmacological or behavioral remediation of acoustic feature discrimination.

Ventrolateral prefrontal cortex and the effects of task demand context on facial affect appraisal in schizophrenia.

Schizophrenia patients display impaired performance and brain activity during facial affect recognition. These impairments may reflect stimulus-driven perceptual decrements and evaluative processing abnormalities. We differentiated these two processes by contrasting responses to identical stimuli presented under different contexts. Seventeen healthy controls and 16 schizophrenia patients performed an fMRI facial affect detection task. Subjects identified an affective target presented amongst foils of differing emotions. We hypothesized that targeting affiliative emotions (happiness, sadness) would create a task demand context distinct from that generated when targeting threat emotions (anger, fear). We compared affiliative foil stimuli within a congruent affiliative context with identical stimuli presented in an incongruent threat context. Threat foils were analysed in the same manner. Controls activated right orbitofrontal cortex (OFC)/ventrolateral prefrontal cortex (VLPFC) more to affiliative foils in threat contexts than to identical stimuli within affiliative contexts. Patients displayed reduced OFC/VLPFC activation to all foils, and no activation modulation by context. This lack of context modulation coincided with a 2-fold decrement in foil detection efficiency. Task demands produce contextual effects during facial affective processing in regions activated during affect evaluation. In schizophrenia, reduced modulation of OFC/VLPFC by context coupled with reduced behavioural efficiency suggests impaired ventral prefrontal control mechanisms that optimize affective appraisal.

Sensory deficits and distributed hierarchical dysfunction in schizophrenia.

OBJECTIVE: Schizophrenia is characterized by widespread cognitive deficits that reflect distributed dysfunction across multiple cortical regions. Here the authors examined the relationship between lower- and higher-level dysfunction within the auditory domain using the event-related brain potentials mismatch negativity (MMN) and P300. METHOD: Event-related brain potentials were obtained from 50 schizophrenia patients and 21 healthy subjects in two conditions: a standard condition employing fixed differences between standard tones and pitch deviants and a novel individualized condition employing tones matched to each individual's tone-discrimination threshold. The relationship among measures was assessed by multiple regression analysis and structural equation modeling. RESULTS: In the standard fixed-deviance condition, schizophrenia patients showed deficits of large effect size in generation of MMN (d>1.26) and P300 (d=1.08) relative to comparison subjects. Assessment of deviance-detection thresholds showed that patients required significantly elevated tone-matching thresholds relative to comparison subjects (d=0.97). When tone differences were individually adjusted to equate tone-matching performance across groups, the groups no longer differed significantly in MMN amplitude during deviant pitch tones, and the degree of deficit in P300 generation was significantly reduced. In both multiple regression analysis and structural equation modeling, MMN and diagnostic group were significant independent predictors of reduced P300 amplitude. MMN generation was well explained (>90% variance) by dipoles seeded within the bilateral auditory cortex. CONCLUSIONS: These findings confirm and extend previous reports of impaired basic sensory processing in schizophrenia and demonstrate significant contributions of early sensory processing dysfunction to higher-order cognitive impairments. Overall, the findings support distributed, hierarchical models of cognitive impairment in schizophrenia, consistent with glutamatergic and other widespread neurochemical models of the disorder.

"It's Not What You Say, But How You Say it": A Reciprocal Temporo-frontal Network for Affective Prosody.

Humans communicate emotion vocally by modulating acoustic cues such as pitch, intensity and voice quality. Research has documented how the relative presence or absence of such cues alters the likelihood of perceiving an emotion, but the neural underpinnings of acoustic cue-dependent emotion perception remain obscure. Using functional magnetic resonance imaging in 20 subjects we examined a reciprocal circuit consisting of superior temporal cortex, amygdala and inferior frontal gyrus that may underlie affective prosodic comprehension. Results showed that increased saliency of emotion-specific acoustic cues was associated with increased activation in superior temporal cortex [planum temporale (PT), posterior superior temporal gyrus (pSTG), and posterior superior middle gyrus (pMTG)] and amygdala, whereas decreased saliency of acoustic cues was associated with increased inferior frontal activity and temporo-frontal connectivity. These results suggest that sensory-integrative processing is facilitated when the acoustic signal is rich in affective information, yielding increased activation in temporal cortex and amygdala. Conversely, when the acoustic signal is ambiguous, greater evaluative processes are recruited, increasing activation in inferior frontal gyrus (IFG) and IFG STG connectivity. Auditory regions may thus integrate acoustic information with amygdala input to form emotion-specific representations, which are evaluated within inferior frontal regions.

Getting the cue: sensory contributions to auditory emotion recognition impairments in schizophrenia.

Individuals with schizophrenia show reliable deficits in the ability to recognize emotions from vocal expressions. Here, we examined emotion recognition ability in 23 schizophrenia patients relative to 17 healthy controls using a stimulus battery with well-characterized acoustic features. We further evaluated performance deficits relative to ancillary assessments of underlying pitch perception abilities. As predicted, patients showed reduced emotion recognition ability across a range of emotions, which correlated with impaired basic tone matching abilities. Emotion identification deficits were strongly related to pitch-based acoustic cues such as mean and variability of fundamental frequency. Whereas healthy subjects' performance varied as a function of the relative presence or absence of these cues, with higher cue levels leading to enhanced performance, schizophrenia patients showed significantly less variation in performance as a function of cue level. In contrast to pitch-based cues, both groups showed equivalent variation in performance as a function of intensity-based cues. Finally, patients were less able than controls to differentiate between expressions with high and low emotion intensity, and this deficit was also correlated with impaired tone matching ability. Both emotion identification and intensity rating deficits were unrelated to valence of intended emotions. Deficits in both auditory emotion identification and more basic perceptual abilities correlated with impaired functional outcome. Overall, these findings support the concept that auditory emotion identification deficits in schizophrenia reflect, at least in part, a relative inability to process critical acoustic characteristics of prosodic stimuli and that such deficits contribute to poor global outcome.

Mismatch negativity to tonal contours suggests preattentive perception of prosodic content.

Modulation of speech conveys information that is decoded within audio-sensory structures. For example, the termination of an utterance with a rise in pitch distinguishes statements and questions. This study evaluated the sensitivity of early auditory structures to such linguistic prosodic distinctions using mismatch negativity (MMN). MMN is a preattentive auditory event-related potential (ERP) sensitive to stimulus deviance. High-density ERP to pitch contour stimuli were collected in a passive listening oddball paradigm from 11 healthy subjects. Voltage analysis revealed significant MMN responses to declarative and interrogative oddball stimuli. Further, MMN was significantly larger to interrogative, than declarative, deviants, indicating non-symmetric brain processing. These MMNs demonstrate that pitch contour abstractions reflecting interrogative/ declarative distinctions can be represented in preattentive auditory sensory memory.

Abnormal superior temporal connectivity during fear perception in schizophrenia.

Patients with schizophrenia have difficulty in decoding facial affect. A study using event-related functional neuroimaging indicated that errors in fear detection in schizophrenia are associated with paradoxically higher activation in the amygdala and an associated network implicated in threat detection. Furthermore, this exaggerated activation to fearful faces correlated with severity of flat affect. These findings suggest that abnormal threat detection processing may reflect disruptions between nodes that comprise the affective appraisal circuit. Here we examined connectivity within this network by determining the pattern of intercorrelations among brain regions (regions of interest) significantly activated during fear identification in both healthy controls and patients using a novel procedure CORANOVA. This analysis tests differences in the interregional correlation strength between schizophrenia and healthy controls. Healthy subjects' task activation was principally characterized by robust correlations between medial structures like thalamus (THA) and amygdala (AMY) and middle frontal (MF), inferior frontal (IF), and prefrontal cortical (PFC) regions. In contrast, schizophrenia patients displayed no significant correlations between the medial regions and either MF or IF. Further, patients had significantly higher correlations between occipital lingual gyrus and superior temporal gyrus than healthy subjects. These between-group connectivity differences suggest that schizophrenia threat detection impairment may stem from abnormal stimulus integration. Such abnormal integration may disrupt the evaluation of threat within fronto-cortical regions.

Social cognition in schizophrenia.

Social cognition in schizophrenia is a rapidly emerging area of study. Because the number and diversity of studies in this area have increased, efforts have been made to better define terms and provide organizing frameworks. A key challenge confronting the study of social cognition in schizophrenia is building bridges between clinical scientists and social neuroscientists. The articles in this theme summarize data-based studies that have attempted to build or strengthen such bridges to better understand the neural bases of social cognitive impairment in schizophrenia.

The neural substrates of impaired prosodic detection in schizophrenia and its sensorial antecedents.

OBJECTIVE: Individuals with schizophrenia show severe deficits in their ability to decode emotions based upon vocal inflection (affective prosody). This study examined neural substrates of prosodic dysfunction in schizophrenia with voxelwise analysis of diffusion tensor magnetic resonance imaging (MRI). METHOD: Affective prosodic performance was assessed in 19 patients with schizophrenia and 19 comparison subjects with the Voice Emotion Identification Task (VOICEID), along with measures of basic pitch perception and executive processing (Wisconsin Card Sorting Test). Diffusion tensor MRI fractional anisotropy valves were used for voxelwise correlation analyses. In a follow-up experiment, performance on a nonaffective prosodic perception task was assessed in an additional cohort of 24 patients and 17 comparison subjects. RESULTS: Patients showed significant deficits in VOICEID and Distorted Tunes Task performance. Impaired VOICEID performance correlated significantly with lower fractional anisotropy values within primary and secondary auditory pathways, orbitofrontal cortex, corpus callosum, and peri-amygdala white matter. Impaired Distorted Tunes Task performance also correlated with lower fractional anisotropy in auditory and amygdalar pathways but not prefrontal cortex. Wisconsin Card Sorting Test performance in schizophrenia correlated primarily with prefrontal fractional anisotropy. In the follow-up study, significant deficits were observed as well in nonaffective prosodic performance, along with significant intercorrelations among sensory, affective prosodic, and nonaffective measures. CONCLUSIONS: Schizophrenia is associated with both structural and functional disturbances at the level of primary auditory cortex. Such deficits contribute significantly to patients' inability to decode both emotional and semantic aspects of speech, highlighting the importance of sensorial abnormalities in social communicatory dysfunction in schizophrenia.

Theory of Mind (ToM) and counterfactuality deficits in schizophrenia: misperception or misinterpretation?

BACKGROUND: Theory of Mind (ToM) refers to the ability to infer another person's mental state based upon interactional information. ToM deficits have been suggested to underlie crucial aspects of social interaction failure in disorders such as autism and schizophrenia, although the development of paradigms for demonstrating such deficits remains an ongoing area of research. Recent studies have explored the use of sarcasm perception, in which subjects must infer an individual's sincerity or lack thereof, as a 'real-life' index of ToM ability, and as an index of functioning of specific right hemispheric structures. Sarcastic detection ability has not previously been studied in schizophrenia, although patients have been shown to have deficits in ability to decode emotional information from speech ('affective prosody'). METHOD: Twenty-two schizophrenia patients and 17 control subjects were tested on their ability to detect sarcasm from spoken speech as well as measures of affective prosody and basic pitch perception. RESULTS: Despite normal overall intelligence, patients performed substantially worse than controls in ability to detect sarcasm (d=2.2), showing both decreased sensitivity (A') in detection of sincerity versus sarcasm and an increased bias (B'') toward sincerity. Correlations across groups revealed significant relationships between impairments in sarcasm recognition, affective prosody and basic pitch perception. CONCLUSIONS: These findings demonstrate substantial deficits in ability to infer an internal subjective state based upon vocal modulation among subjects with schizophrenia. Deficits were related to, but were significantly more severe than, more general forms of prosodic and sensorial misperception, and are consistent with both right hemispheric and 'bottom-up' theories of the disorder.

Sensory contributions to impaired prosodic processing in schizophrenia.

BACKGROUND: Deficits in affect recognition are prominent features of schizophrenia. Within the auditory domain, patients show difficulty in interpreting vocal emotional cues based on intonation (prosody). The relationship of these symptoms to deficits in basic sensory processing has not been previously evaluated. METHODS: Forty-three patients and 34 healthy comparison subjects were tested on two affective prosody measures: voice emotion identification and voice emotion discrimination. Basic auditory sensory processing was measured using a tone-matching paradigm and the Distorted Tunes Test (DTT). A subset of subjects was also tested on facial affect identification and discrimination tasks. RESULTS: Patients showed significantly impaired performance on all emotion processing tasks. Within the patient group, a principal components analysis demonstrated significant intercorrelations between basic pitch perception and affective prosodic performance. In contrast, facial affect recognition deficits represented a distinct second component. Prosodic affect measures correlated significantly with severity of negative symptoms and impaired global outcome. CONCLUSIONS: These results demonstrate significant relationships between basic auditory processing deficits and impaired receptive prosody in schizophrenia. The separate loading of auditory and visual affective recognition measures suggests that within-modality factors may be more significant than cross-modality factors in the etiology of affect recognition deficits in schizophrenia.