Language in schizophrenia and its relationship to formal thought disorder

Narrative-Derived Indices of Metacognition among People with Schizophrenia: Associations with Self-Reported and Performance-Based Social Functioning

Metacognitive functioning-which broadly encompasses the mental processes involved in thinking about the thinking of one's self and the thinking of others-is often impaired among individuals living with schizophrenia and may contribute to difficulties in social and interpersonal functioning. Although the majority of studies assessing metacognition among individuals with schizophrenia use standardized, laboratory-based measurements, an increasing number of studies have measured metacognitive capacity using natural language produced by individuals living with mental illness. At the same time, less is known about how language-derived indices of metacognitive function relate to key social outcomes among people with schizophrenia. The primary objective of this study was to employ a validated language coding system (the Metacognition Assessment Scale, Abbreviated; MAS-A) to assess metacognitive functioning from the spoken life narratives of individuals with schizophrenia (n = 32) and community controls (n = 15). Among individuals with schizophrenia, we also examined the associations between language-derived metacognition and measures of self-reported and performance-based social functioning. Our results suggest that most aspects of metacognition in our sample were not significantly diminished in people with schizophrenia compared to community controls. Unexpectedly, the MAS-A subscale related to one's ability to master psychological difficulties was rated higher among individuals with schizophrenia. Further, our results suggest that among people with schizophrenia, higher metacognitive functioning in the domain of self-reflectivity was associated with poorer self-reported social functioning, while a greater metacognitive awareness of other individuals' minds was associated with better scores on aspects of performance-based social functioning. Collectively, these results underscore the utility of assessing metacognitive functioning via life-story narratives to understand social outcomes and highlight possible aspects of resiliency among individuals who have experienced a serious mental illness.

Unraveling the molecular interactions between α7 nicotinic receptor and a RIC3 variant associated with backward speech

Recent work putatively linked a rare genetic variant of the chaperone Resistant to Inhibitors of acetylcholinesterase (RIC3) (NM_024557.4:c.262G > A, NP_078833.3:p.G88R) to a unique ability to speak backwards, a language skill that is associated with exceptional working memory capacity. RIC3 is important for the folding, maturation, and functional expression of α7 nicotinic acetylcholine receptors (nAChR). We compared and contrasted the effects of RIC3G88R on assembly, cell surface expression, and function of human α7 receptors using fluorescent protein tagged α7 nAChR and Förster resonance energy transfer (FRET) microscopy imaging in combination with functional assays and 125I-α-bungarotoxin binding. As expected, the wild-type RIC3 protein was found to increase both cell surface and functional expression of α7 receptors. In contrast, the variant form of RIC3 decreased both. FRET analysis showed that RICG88R increased the interactions between RIC3 and α7 protein in the endoplasmic reticulum. These results provide interesting and novel data to show that a RIC3 variant alters the interaction of RIC3 and α7, which translates to decreased cell surface and functional expression of α7 nAChR.

Linguistic anomalies observed in the Sentence Completion Test in patients with schizophrenia

BACKGROUND

Schizophrenia is a chronic, debilitating disorder characterised by distorted thinking, perceptions, behaviours, and even language impairments. We investigated the linguistic anomalies in Korean schizophrenia patients compared to non-psychotic psychiatric controls to determine whether the linguistic anomalies in English speakers with schizophrenia were replicated in Korean speakers.

METHODS

Thirty-four schizophrenia patients and 70 non-psychotic psychiatric controls were included in this study. The SCT was utilised as the text data for analysis. For linguistic analysis, we evaluated texts regarding semantics and syntax. We separately counted the number of semantic or syntactic errors in the written texts of study participants and compared them between patients and controls.

RESULTS

Schizophrenia patients showed significantly more semantic errors (p < .001) and syntactic errors (p < .001) per 1,000 characters than non-psychotic psychiatric controls. Specifically, inappropriate word or syntactic component selection is noticeable in schizophrenia patients. These differences were still significant after adjusting for general intelligence measured by the K-WAIS-IV.

CONCLUSION

Schizophrenia patients showed both semantic and syntactic errors in written language. Moreover, these errors seemed to be partly independent of general intelligence. Notably, patients showed a noticeable number of syntactic errors. Further investigation into the language of patients with schizophrenia and schizophrenia-spectrum disorders is required.

Differences in pragmatic communication skills of adults with intellectual disabilities and dual diagnoses

INTRODUCTION

Pragmatics includes a set of skills related to language structure and meaning that allow the speaker to use the language appropriately and in accordance with different communication situations. The aim of this research was to determine the differences in pragmatic communication skills of adults with intellectual disabilities, dual diagnoses, and typical development, and to determine the effects of gender, age, the level of intellectual functioning and speech comprehension on their achievements on two assessment instruments.

METHODS

The sample included 180 adults (60 typically developing participants, 60 with intellectual disabilities, and 60 participants with dual diagnoses). We used two instruments to assess pragmatic communication skills - Communication Checklist - Adult, CC-A, and the Assessment Battery for Communication, ABaCo. In order to test the differences between the three groups of participants, we used canonical discriminant analysis.

RESULTS

Discriminant analysis revealed two significant canonical functions. Function one (speech comprehension and the level of intellectual disability, social engagement, and paralinguistic scale) differentiates between typically developing participants and participants with dual diagnoses the most. The second canonical function (language structure, linguistic scale, paralinguistic scale, extralinguistic scale, and context scale) differentiates between participants with intellectual disabilities and participants with dual diagnoses the most. According to the results, age did not affect pragmatic achievements.

DISCUSSION

Pragmatic skills are very complex, and different instruments measure different dimensions of these abilities. The results of this research lead to the conclusion that we can differentiate between the pragmatic abilities of typically developing people, people with intellectual disabilities, and those with dual diagnoses with the help of the ABaCo battery and the CC-A questionnaire.

Agency of Subjects and Eye Movements in Schizophrenia Spectrum Disorders

People with schizophrenia spectrum disorders (SSD) show anomalies in language processing with respect to "who is doing what" in an action. This linguistic behavior is suggestive of an atypical representation of the formal concepts of "Agent" in the lexical representation of a verb, i.e., its thematic grid. To test this hypothesis, we administered a silent-reading task with sentences including a semantic violation of the animacy trait of the grammatical subject to 30 people with SSD and 30 healthy control participants (HCs). When the anomalous grammatical subject was the Agent of the event, a significant increase of Gaze Duration was observed in HCs, but not in SSDs. Conversely, when the anomalous subject was a Theme, SSDs displayed an increased probability of go-back movements, unlike HCs. These results are suggestive of a higher tolerability for anomalous Agents in SSD compared to the normal population. The fact that SSD participants did not show a similar tolerability for anomalous Themes rules out the issue of an attention deficit. We suggest that general communication abilities in SSD might benefit from explicit training on deep linguistic structures.

Language disorder as a marker for schizophrenia

A language disorder is a significant symptom of schizophrenia. A psychiatrist can find this disorder when interviews with a patient. Screening and diagnosis in patients with schizophrenia alone rely heavily on interviews conducted on patients and any instructions captured from patients both verbally and nonverbally. A psychiatrist can also analyze the language aspects in schizophrenia from a language level perspective ranging from phonetic to pragmatic. This analysis paves the way for the process of interference detection since the prodromal phase. Language disorder in schizophrenia is often associated with impaired thinking processes. However, with the development of science and technology today, there is an objective and quantitative method of computational analysis of language through the Natural Language Processing process with a semantic space model that allows a psychiatrist to learn aspects of the human language process, especially in semantic and pragmatic aspects. The review provides a groundbreaking proposal for biomarkers for schizophrenia that have not been available so far through the assessment of language disorders in patients with schizophrenia. Objective and accurate detection of language disorders in schizophrenia can be a modality for psychiatrists to screen, make diagnoses, determine prognosis, evaluate therapies, and monitor recurrence using existing technology media.

Processing Argument Structure and Syntactic Complexity in People with Schizophrenia Spectrum Disorders

INTRODUCTION

Deficits in language comprehension and production have been repeatedly observed in Schizophrenia Spectrum Disorders (SSD). However, the characterization of the language profile of this population is far from complete, and the relationship between language deficits, impaired thinking and cognitive functions is widely debated.

OBJECTIVE

The aims of the present study were to assess production and comprehension of verbs with different argument structures, as well as production and comprehension of sentences with canonical and non-canonical word order in people with SSD. In addition, the study investigated the relationship between language deficits and cognitive functions.

METHODS

Thirty-four participants with a diagnosis of SSD and a group of healthy control participants (HC) were recruited and evaluated using the Italian version of the Northwestern Assessment of Verbs and Sentences (NAVS, Cho-Reyes & Thompson, 2012; Barbieri et al., 2019).

RESULTS

Results showed that participants with SSD were impaired - compared to HC - on both verb and sentence production, as well as on comprehension of syntactically complex (but not simple) sentences. While verb production was equally affected by verb-argument structure complexity in both SSD and HC, sentence comprehension was disproportionately more affected by syntactic complexity in SSD than in HC. In addition, in the SSD group, verb production deficits were predicted by performance on a measure of visual attention, while sentence production and comprehension deficits were explained by performance on measures of executive functions and working memory, respectively.

DISCUSSION

Our findings support the hypothesis that language deficits in SSD may be one aspect of a more generalized, multi-domain, cognitive impairment, and are consistent with previous findings pointing to reduced inter- and intra-hemispheric connectivity as a possible substrate for such deficits. The study provides a systematic characterization of lexical and syntactic deficits in SSD and demonstrates that psycholinguistically-based assessment tools may be able to capture language deficits in this population.

Detecting formal thought disorder by deep contextualized word representations

Computational linguistics has enabled the introduction of objective tools that measure some of the symptoms of schizophrenia, including the coherence of speech associated with formal thought disorder (FTD). Our goal was to investigate whether neural network based utterance embeddings are more accurate in detecting FTD than models based on individual indicators. The present research used a comprehensive Embeddings from Language Models (ELMo) approach to represent interviews with patients suffering from schizophrenia (N=35) and with healthy people (N=35). We compared its results to the approach described by Bedi et al. (2015), referred to here as the coherence model. Evaluations were also performed by a clinician using the Scale for the Assessment of Thought, Language and Communication (TLC). Using all six TLC questions the ELMo obtained an accuracy of 80% in distinguishing patients from healthy people. Previously used coherence models were less accurate at 70%. The classifying clinician was accurate 74% of the time. Our analysis shows that both ELMo and TLC are sensitive to the symptoms of disorganization in patients. In this study methods using text representations from language models were more accurate than those based solely on the assessment of FTD, and can be used as measures of disordered language that complement human clinical ratings.

Language disturbances in schizophrenia: the relation with antipsychotic medication

Language disturbances are key aberrations in schizophrenia. Little is known about the influence of antipsychotic medication on these symptoms. Using computational language methods, this study evaluated the impact of high versus low dopamine D₂ receptor (D2R) occupancy antipsychotics on language disturbances in 41 patients with schizophrenia, relative to 40 healthy controls. Patients with high versus low D2R occupancy antipsychotics differed by total number of words and type-token ratio, suggesting medication effects. Both patient groups differed from the healthy controls on percentage of time speaking and clauses per utterance, suggesting illness effects. Overall, more severe negative language disturbances (i.e. slower articulation rate, increased pausing, and shorter utterances) were seen in the patients that used high D2R occupancy antipsychotics, while less prominent disturbances were seen in low D2R occupancy patients. Language analyses successfully predicted drug type (sensitivity = 80.0%, specificity = 76.5%). Several language disturbances were more related to drug type and dose, than to other psychotic symptoms, suggesting that language disturbances may be aggravated by high D2R antipsychotics. This negative impact of high D2R occupancy drugs may have clinical implications, as impaired language production predicts functional outcome and degrades the quality of life.

How Can Poetry Support the Understanding of Psychotic Experiences? - A Conceptual Review

OBJECTIVE

The therapeutic application of poetry for those who have experienced psychosis remains under researched and potentially undervalued. This paper presents a conceptual review exploring the relationship between poetry and psychosis, based on a synthesis of existing literature.

RESEARCH DESIGN AND METHODS

The review identified papers from a range of sources and disciplines. Initial searches were undertaken using databases CINAHL, PsycINFO and ASSIA; this search was then followed up with a library search for key texts and a further search for associated grey literature involving exploring blogs and conference presentations. The data was then synthesized based on methods from both narrative review and thematic analysis to generate a conceptual framework.

RESULTS

The results reveal a conceptual framework comprised of three domains: i) psychotic language as meaningful poetics, ii) poetry as an expression of psychosis and iii) poetic exchange as therapeutic practice. The conceptual framework proposes that not only can psychosis be understood as meaningful poetics, but also that poetry may offer meaningful linguistic opportunities to aid the expression and narration of self and experiences. The potential for extending our understanding of the poetry in this way is analogous to forms of talking therapy, and this may be a base for extending understanding and communicative practice for a range of mental health professions.

CONCLUSION

The conceptual framework suggests a novel understanding of psychosis in relation to poetry, moving away from traditional biomedical paradigms and placing importance upon individual narratives.

Language in schizophrenia and aphasia: the relationship with non-verbal cognition and thought disorder

Objective: To determine the relationship between language abnormalities and broader cognitive impairment and thought disorder by examining language and cognition in schizophrenia and aphasia (a primary language disorder).Methods: Cognitive and linguistic profiles were measured with a battery of standardised tests, and compared in a clinical population of n = 50 (n = 30 with schizophrenia and n = 20 with aphasia) and n = 61 non-clinical comparisons (n = 45 healthy controls and n = 16 non-affected first-degree relatives of patients with schizophrenia).Results: Both clinical groups showed linguistic deficits. Verbal impairment was more severe in participants with aphasia, whereas non-verbal performance was more affected in participants with schizophrenia. In schizophrenia, but not in aphasia, verbal and non-verbal performance were associated. Formal thought disorder was associated with impairment in executive function and in grammatical, but not naming, tasks.Conclusion: While patients with schizophrenia and aphasia showed language impairments, the nature and cognitive basis of these impairments may be different; language performance disassociates from broader cognitive functioning in aphasia but may be an intrinsic expression of a broader cognitive impairment in schizophrenia. Thought disorder may represent a core malfunction of grammatical processing. Results suggests that communicative ability may be a valid target in cognitive remediation strategies in schizophrenia.

Neurocognitive and linguistic correlates of positive and negative formal thought disorder: A meta-analysis

Executive dysfunction and language impairment are the most prominent neuropsychological models of formal thought disorder (FTD) in schizophrenia. However, available studies have provided contradictory findings regarding the accuracy of these models. Furthermore, specific neurocognitive underpinnings of positive FTD (PosFTD) and negative FTD (NegFTD) are not clear. Following the systematic review of schizophrenia studies, a random-effects meta-analysis of the relationship between FTD and neurocognition/language in schizophrenia was conducted in 52 reports including 2805 patients. Neurocognition was significantly associated with both PosFTD (r = -0.21, CI = -0.14 to -0.27) and NegFTD (r = -0.24, CI = -0.18 to -0.30). Both PosFTD (r = ranged from -0.18 to -0.27) and NegFTD (r = ranged from -0.19 to -0.23) were significantly correlated with verbal memory, visual memory, attention, and processing speed. In meta-analyses of executive functions, PosFTD was significantly associated with working memory (r = -0.21), planning (r = -0.19), and inhibition (r = -0.21) and NegFTD was significantly associated with planning (r = -0.27), fluency (r = -0.27), and working memory (r = -0.24). In meta-analyses of linguistic variables, PosFTD was associated with deficits in syntactic comprehension (r = -0.27) and semantic processing (r = -0.18). In contrast, NegFTD was associated only with semantic comprehension (r = -0.21). Both PosFTD and NegFTD were significantly associated with executive dysfunction, neurocognitive deficits and semantic dysfunction but syntactic deficits were more specific to PosFTD. There were also some distinct patterns of relationships between the pattern of executive dysfunction and types of FTD. Fluency deficit was associated more strongly with NegFTD and poor inhibition was more specifically related to PosFTD. Current findings suggest that neurocognitive and linguistic correlates of PosFTD and NegFTD might be partly different.

Comprehension of Embedded Clauses in Schizophrenia With and Without Formal Thought Disorder

Formal thought disorder (FTD) in schizophrenia (SZ) is clinically manifested primarily through language production, where linguistic studies have reported numerous anomalies including lesser use of embedded clauses. Here, we explored whether problems of language may extend to comprehension and clause embedding in particular. A sentence-picture matching task was designed with two conditions in which embedded clauses were presupposed as either true (factive) or not. Performance across these two conditions was compared in people with SZ and moderate-to-severe FTD (SZ + FTD), SZ with minimal FTD (SZ-FTD), first-degree relatives of people with SZ, and neurotypical controls. The SZ + FTD group performed significantly worse than all others in both conditions, and worse in the nonfactive than in the factive one. These results demonstrate language dysfunction in comprehension specific to FTD is a critical aspect of grammatical complexity and its associated meaning, which has been independently known to be cognitively significant as well.

Language comprehension and neurocognition independently and concurrently contribute to formal thought disorder severity in schizophrenia

Formal thought disorder (FTD) in schizophrenia is a prevalent symptom that has a significant impact on patients but low remediation options. This is largely due to a still unclear aetiology, where both neurocognitive and language dysfunction have been shown to contribute. Given established relationships between neurocognition and language themselves, this study aimed to examine if language comprehension impairments have a significant effect on FTD severity independent of neurocognition. 54 schizophrenia/schizoaffective disorder patients (M = 43.35, SD = 10.74) completed three measures of language comprehension along with the MATRICS Consensus Cognitive Battery and the D-KEFS Colour Word Interference Test. Symptomatology was assessed using the Positive and Negative Symptom Scale and the Scale for the Assessment of Thought, Language and Communication. Hierarchical linear regression analyses revealed syntactic sentence processing had a significant, and independent, contribution to positive FTD severity above neurocognition, while semantic sentence processing and single word semantic processing did not. The findings support the existence of a specific relationship between language comprehension dysfunction and FTD; however the question of generalisation to all aspects of language processing or FTD types needs further investigation. The establishment of a specific language-related impairment in schizophrenia which contributes independently to FTD severity supports the benefit of language-based remediation approaches for alleviating FTD symptoms and their effects. Clinical, aetiological and nosological implications of the results are discussed.

The language profile of formal thought disorder

Formal thought disorder (FTD) is clinically manifested as disorganized speech, but there have been only few investigations of its linguistic properties. We examined how disturbance of thought may relate to the referential function of language as expressed in the use of noun phrases (NPs) and the complexity of sentence structures. We used a comic strip description task to elicit language samples from 30 participants with schizophrenia (SZ), 15 with moderate or severe FTD (SZ + FTD), and 15 minimal or no FTD (SZ−FTD), as well as 15 first-degree relatives of people with SZ (FDRs) and 15 neurotypical controls (NC). We predicted that anomalies in the normal referential use of NPs, sub-divided into definite and indefinite NPs, would identify FTD; and also that FTD would also be linked to reduced linguistic complexity as specifically measured by the number of embedded clauses and of grammatical dependents. Participants with SZ + FTD produced more referential anomalies than NC and produced the fewest definite NPs, while FDRs produced the most and thus also differed from NC. When referential anomalies were classed according to the NP type in which they occurred, the SZ + FTD group produced more anomalies in definite NPs than NC. Syntactic errors did not distinguish groups, but the SZ + FTD group exhibited significantly less syntactic complexity than non-SZ groups. Exploratory regression analyses suggested that production of definite NPs distinguished the two SZ groups. These results demonstrate that FTD can be identified in specific grammatical patterns which provide new targets for detection, intervention, and neurobiological studies.

Automated analysis of written narratives reveals abnormalities in referential cohesion in youth at ultra high risk for psychosis

Schizophrenia and at-risk populations are suggested to exhibit referential cohesion deficits in language production (e.g., producing fewer pronouns or nouns that clearly link to concepts from previous sentences). Much of this work has focused on transcribed speech samples, while no work to our knowledge has examined referential cohesion in written narratives among ultra high risk (UHR) youth using Coh-Metrix, an automated analysis tool. In the present study, written narratives from 84 individuals (UHR=41, control=43) were examined. Referential cohesion variables and relationships with symptoms and relevant cognitive variables were also investigated. Findings reveal less word "stem" overlap in narratives produced by UHR youth compared to controls, and correlations with symptom domains and verbal learning. The present study highlights the potential usefulness of automated analysis of written narratives in identifying at-risk youth and these data provide critical information in better understanding the etiology of psychosis. As writing production is commonly elicited in educational contexts, markers of aberrant cohesion in writing represent significant potential for identifying youth who could benefit from further screening, and utilizing software that is easily accessible and free may provide utility in academic and clinical settings.

Neuropsychological correlates of schizotypy: a systematic review and meta-analysis of cross-sectional studies

INTRODUCTION

Cognitive deficits can precede the onset of psychotic episodes and predict the onset of the illness in individuals with schizotypy traits. In some studies, high levels of schizotypy were associated with impairments in memory, attention, executive functions, and verbal fluency. This review provides a more comprehensive understanding of cognitive impairments related to schizoytpy.

METHODS

 A systematic review of "schizotypy and neuropsychological measures" was conducted, and it retrieved 67 studies. All papers with case-control design showing means and standard deviations from neuropsychological measures were included in a meta-analysis (n = 40). A comparison between our finding and another metaanalysis with patients with schizophrenia-spectrum disorders [Fatouros-Bergman, H., Cervenka, S., Flyckt, L., Edman, G., & Farde, L. (2014). Meta-analysis of cognitive performance in drugnaive patients with schizophrenia. Schizophrenia Research. doi: 10.1016/j.schres.2014.06.034 ] was performed to study the similarities on the MATRICS domains between the two disorders.

RESULTS

We found evidence of worse functioning of verbal and visual-spatial working memory, and of language in people with schizotypy or with schizotypal traits. Working memory deficit is present in both schizotypy and schizophrenia with larger effect sizes compared to other domains.

CONCLUSIONS

 Working memory deficit might be a cognitive marker of the risk of psychosis. Interventions targeting cognitive deficits early may be crucial to the prevention of psychosis.

Characterising receptive language processing in schizophrenia using word and sentence tasks

INTRODUCTION

Language dysfunction is proposed to relate to the speech disturbances in schizophrenia, which are more commonly referred to as formal thought disorder (FTD). Presently, language production deficits in schizophrenia are better characterised than language comprehension difficulties. This study thus aimed to examine three aspects of language comprehension in schizophrenia: (1) the role of lexical processing, (2) meaning attribution for words and sentences, and (3) the relationship between comprehension and production.

METHODS

Fifty-seven schizophrenia/schizoaffective disorder patients and 48 healthy controls completed a clinical assessment and three language tasks assessing word recognition, synonym identification, and sentence comprehension. Poorer patient performance was expected on the latter two tasks.

RESULTS

Recognition of word form was not impaired in schizophrenia, indicating intact lexical processing. Whereas single-word synonym identification was not significantly impaired, there was a tendency to attribute word meanings based on phonological similarity with increasing FTD severity. Importantly, there was a significant sentence comprehension deficit for processing deep structure, which correlated with FTD severity.

CONCLUSIONS

These findings established a receptive language deficit in schizophrenia at the syntactic level. There was also evidence for a relationship between some aspects of language comprehension and speech production/FTD. Apart from indicating language as another mechanism in FTD aetiology, the data also suggest that remediating language comprehension problems may be an avenue to pursue in alleviating FTD symptomatology.

Dysfluent Handwriting in Schizophrenic Outpatients

Taking into account findings in the literature, the author aimed to test whether specific graphical characteristics of handwriting can distinguish patients diagnosed with schizophrenic disorders from healthy controls. Handwriting samples (one sample from each person) from 60 outpatients (29 women, 31 men; age M = 28.5, SD = 5.4) with paranoid schizophrenia were analyzed by three documents examiners and were compared to samples from 60 controls (30 men, 30 women, age M = 28.0, SD = 3.0) without psychiatric disorders. Document examiners assessed 32 graphical features potentially related to schizophrenia. The comparisons between groups revealed that only 7 out of 32 handwriting properties were significantly different in the handwriting of schizophrenic outpatients from controls: the calligraphic forms of letters, loops in ovals, lacking of dots, tremor, sinusoidal baseline, and irregularities size of lower zone. These findings are discussed in terms of motor disturbances in schizophrenia and in relation to the previous research on handwriting of other mental disorders. Similarities between the graphical patterns of handwriting of schizophrenic patients and those of other mental disorders and/or other mental states have been demonstrated.

Lexical Characteristics of Emotional Narratives in Schizophrenia: Relationships With Symptoms, Functioning, and Social Cognition

Previous research has suggested that complexity of speech, speech rate, use of emotion words, and use of pronouns are all potential indicators of important clinical components of schizophrenia, but little research has examined the relationships of these disturbances to cognitive variables impaired in schizophrenia, including social cognition. The current study examined these lexical differences to better characterize the cognitive substrates of speech disturbances in schizophrenia. Brief narratives of individuals with schizophrenia (n = 42) and non-clinical controls (n = 48) were compared according to their lexical characteristics, and these were examined for relationships to social cognition and real-world functioning. Significant differences between the groups were found in words per sentence (related to functioning, but not negative symptoms) as well as pronoun use (related to attributional style and theory of mind). Additionally, lexical characteristics effectively distinguished individuals with schizophrenia from non-clinical controls. Language disturbances in schizophrenia seem related to social cognition impairments and real-world functioning, and are a robust indicator of clinical status.

Verbatim recall in formal thought disorder in schizophrenia: a study of contextual influences

INTRODUCTION

We have previously reported that people with schizophrenia and formal thought disorder (FTD) were disproportionately impaired in recalling sentences verbatim and in judging their plausibility. We proposed that these deficits were due to impairment in integrating higher-order semantic information to construct a global whole. However, it is also possible that a lower-level linguistic problem affecting lexical activation could account for this pattern.

METHODS

The present study analysed and compared the sentence repetition errors produced by people with FTD, people with schizophrenia who were non-FTD and healthy controls. Errors due to failure of activation of the target lexical items were differentiated from those due to erroneous integration of information.

RESULTS

People with FTD produced significantly more unrelated lexical substitutions and omissions in their corpora than the other two groups, indicating an impairment of activation. In addition, they made significantly more erroneous contextual inferences and unrelated references, suggesting they were impaired in reconstructing the global whole from successfully activated items.

CONCLUSION

These findings are consistent with a dual process account of impairments in FTD. Difficulties in repeating and judging sentence acceptability arises due to a combination of difficulty with activation and deficits in using linguistic context to process and produce speech. It is suggested that processing difficulties in FTD result from an impairment in using semantic context to drive lexical access and construction of a global whole.

Amusia and protolanguage impairments in schizophrenia

BACKGROUND

Both language and music are thought to have evolved from a musical protolanguage that communicated social information, including emotion. Individuals with perceptual music disorders (amusia) show deficits in auditory emotion recognition (AER). Although auditory perceptual deficits have been studied in schizophrenia, their relationship with musical/protolinguistic competence has not previously been assessed.

METHOD

Musical ability was assessed in 31 schizophrenia/schizo-affective patients and 44 healthy controls using the Montreal Battery for Evaluation of Amusia (MBEA). AER was assessed using a novel battery in which actors provided portrayals of five separate emotions. The Disorganization factor of the Positive and Negative Syndrome Scale (PANSS) was used as a proxy for language/thought disorder and the MATRICS Consensus Cognitive Battery (MCCB) was used to assess cognition.

RESULTS

Highly significant deficits were seen between patients and controls across auditory tasks (p < 0.001). Moreover, significant differences were seen in AER between the amusia and intact music-perceiving groups, which remained significant after controlling for group status and education. Correlations with AER were specific to the melody domain, and correlations between protolanguage (melody domain) and language were independent of overall cognition.

DISCUSSION

This is the first study to document a specific relationship between amusia, AER and thought disorder, suggesting a shared linguistic/protolinguistic impairment. Once amusia was considered, other cognitive factors were no longer significant predictors of AER, suggesting that musical ability in general and melodic discrimination ability in particular may be crucial targets for treatment development and cognitive remediation in schizophrenia.

Higher-order semantic processing in formal thought disorder in schizophrenia

Higher-order semantic impairments and lack of sensitivity to linguistic context have both been implicated in formal thought disorder (FTD) in schizophrenia. Most investigations have focused on comprehension. We investigated the processing of higher-order semantic relations and the role of emotional arousal in FTD patients' linguistic comprehension and production. We compared FTD schizophrenia patients (n=14) with non-FTD schizophrenia patients (n=18) and healthy controls (n=15) on sense-judgment and repetition tasks, in emotionally negative and neutral conditions. We predicted that the FTD group would display poor sensitivity compared to the other two groups in comprehension and production, and that this would be exacerbated by sentence complexity and negative emotional arousal. The emotional manipulation was not robustly successful, and did not affect task performance in the patient groups. FTD patients made significantly more errors on sense-judgments and repetition than the other two groups. Complexity affected all groups to a similar extent in sense-judgments, but affected FTD patients disproportionately in the repetition task. These results support the view that a lack of sensitivity to context underlies FTD in comprehension and production stages of processing. Patients fail to utilise linguistic context to integrate lexical forms into a global whole and guide their access to lexical targets.

Speech disturbances and quality of life in schizophrenia: differential impacts on functioning and life satisfaction

Speech disturbances in schizophrenia impact on the individual's communicative ability. Although they are considered a core feature of schizophrenia, comparatively little work has been done to examine their impact on the life experiences of patients. This study aimed to examine the relationship between schizophrenia speech disturbances, including those traditionally known as formal thought disorder (TD), and quality of life (QoL). It assessed effects on functioning (objective QoL) and satisfaction (subjective QoL) concurrently, while controlling for the influence of neurocognition and depression. Fifty-four patients with schizophrenia/schizoaffective disorder were administered the MATRICS Consensus Cognitive Battery (MCCB), the PANSS, MADRS (with separate ratings for negative TD [verbal underproductivity] and positive TD [verbal disorganisation and pressured speech]) and Lehman's QOLI assessing both objective and subjective QoL. Ratings of positive and negative TD, depression, and general neurocognition were entered into hierarchical regressions to explore their relationship with both life functioning and satisfaction. Verbal underproductivity was a significant predictor of objective QoL, while pressured speech had a trend association with subjective QoL. This suggests a differential relationship between speech disturbances and QoL. Verbal underproductivity seems to affect daily functioning and relations with others, while pressured speech is predictive of satisfaction with life. The impact of verbal underproductivity on QoL suggests it to be an important target for rehabilitation in schizophrenia.

Understanding the communicative impairments in schizophrenia: a preliminary study

The aim of the present study was to evaluate the pragmatic abilities of patients with schizophrenia in a variety of pragmatic phenomena expressed through different communicative means (language, gestures, and paralinguistic modality). For this purpose we used the Assessment Battery of Communication (ABaCo; Sacco et al., 2008). The ABaCo is a validated clinical tool for assessing pragmatic skills, which comprises five evaluation scales-linguistic, extralinguistic, paralinguistic, context, and conversational-investigating both comprehension and production of the main pragmatic phenomena involved in a communicative exchange, such as direct and indirect speech acts, irony, deceit, the violation of Grice's maxims, topic management, and turn-taking. The battery was administered to a group of seventeen patients with schizophrenia, and matched healthy controls. We expected the clinical group to perform widely worse than the control group in the different pragmatic dimensions investigated. Results showed that patients with schizophrenia performed significantly worse than controls on all the five scales of the battery, both in comprehension and production tasks. Moreover, the results within each scale showed a differentiated performance in the clinical group among the pragmatic phenomena, with irony assessed as the most difficult task. The implications of these results for research and treatment in schizophrenia are discussed.

LEARNING OUTCOMES

After reading this article, the reader will be able to: (1) summarize thepreliminary assessment of pragmatic impairments in patients with schizophrenia; (2) describea variegated communicative profile regarding different pragmatic phenomena; and (3) discuss the planning and evaluating specific rehabilitation programs.

Formal Thought Disorder and language impairment in schizophrenia

Schizophrenia is a psychiatric illness in which disorders of thought content are a prominent feature. The disruption of normal flow of thought, or “Formal Thought Disorder” (FTD), has been traditionally assessed through the content and form of patients’ speech, and speech abnormalities in schizophrenia were considered as a by-product of the disruption in conceptual structures and associative processes related to psychosis. This view has been changed due to increasing evidence that language per se is impaired in schizophrenia, especially its semantic, discursive, and pragmatic aspects. Schizophrenia is currently considered by some authors as a “language related human specific disease” or “logopathy”, and the neuroanatomical and genetic correlates of the language impairment in these patients are under investigation. Such efforts may lead to a better understanding about the pathophysiology of this devastating mental disease. We present some current concepts related to FTD as opposed to primary neurolinguistic abnormalities in schizophrenia.

Schizophrenia impairs phonological speech production: a preliminary report

INTRODUCTION

Schizophrenia causes clinically conspicuous impairment of syntax and semantics as part of the disorganisation syndrome; however, little is known regarding its effect on the phonological stage of speech, where word meanings are resolved into speech imagery.

METHODS

We used a "tongue-twister" task to probe phonological speech production and its clinical associations in six schizophrenia patients and 16 controls.

RESULTS

Errors induced by phonological similarity were more common in the patients (p=.003), were positively associated with psychomotor poverty symptoms (p=.02) and negatively associated with reality distortion symptoms (p=.03).

CONCLUSIONS

Our findings suggest that phonological speech production is markedly disrupted by schizophrenia. Further, this phonological abnormality is distinct from disorganisation syndrome.

Semantic Processing and Thought Disorder in Childhood-Onset Schizophrenia: Insights from fMRI

Impairments in language processing and thought disorder are core symptoms of schizophrenia. Here we used fMRI to investigate functional abnormalities in the neural networks subserving sentence-level language processing in childhood-onset schizophrenia (COS). Fourteen children with COS (mean age: 13.34; IQ: 95) and 14 healthy controls (HC; mean age: 12.37; IQ: 104) underwent fMRI while performing a semantic judgment task previously shown to differentially engage semantic and syntactic processes. We report four main results. First, different patterns of functional specialization for semantic and syntactic processing were observed within each group, despite similar level of task performance. Second, after regressing out IQ, significant between-group differences were observed in the neural correlates of semantic and, to a lesser extent, syntactic processing, with HC children showing overall greater activity than COS children. Third, while these group differences were not related to effects of medications, a significant negative correlation was observed in the COS group between neuroleptic dosage and activity in the left inferior frontal gyrus for the semantic condition. Finally, COS children's level of thought disorder was significantly correlated with task-related activity in language-relevant networks. Taken together, these findings suggest that children with COS exhibit aberrant patterns of neural activity during semantic, and to a lesser extent syntactic, processing and that these functional abnormalities in language-relevant networks are significantly related to severity of thought disorder.

Neurocognition and social skill in older persons with schizophrenia and major mood disorders: An analysis of gender and diagnosis effects

Effective social interactions necessary for getting affiliative and instrumental needs met require the smooth integration of social skills, including verbal, non-verbal, and paralinguistic behaviors. Schizophrenia is characterized by prominent impairments in social and role functioning, and research on younger individuals with the illness has shown that social skills deficits are both common and distinguish the disease from other psychiatric disorders. However, less research has focused on diagnostic differences and correlates of social skills in older persons with schizophrenia. To address this question, we examined diagnostic and gender differences in social skills in a community-dwelling sample of 183 people older than age 50 with severe mental illness, and the relationships between social skills and neurocognitive functioning, symptoms, and social contact.Individuals with schizophrenia had worse social skills than those with bipolar disorder or major depression, with people with schizoaffective disorder in between. Social contact and cognitive functioning, especially executive functions and verbal fluency, were strongly predictive of social skills in people with schizophrenia and schizoaffective disorder, but not those with mood disorder. Other than blunted affect, symptoms were not predictive of social skills in either the schizophrenia spectrum or the mood disorder group. Older age was associated with worse social skills in both groups, whereas female gender was related to better skills in the mood disorder group, but not the schizophrenia group. The findings suggest that poor social skills, which are related to the cognitive impairment associated with the illness, are a fundamental feature of schizophrenia that persists from the onset of the illness into older age.

The Genetic Basis of Thought Disorder and Language and Communication Disturbances in Schizophrenia

Thought disorder as well as language and communication disturbances are associated with schizophrenia and are over-represented in clinically unaffected relatives of schizophrenics. All three kinds of dysfunction involve some element of deviant verbalizations, most notably, semantic anomalies. Of particular importance, thought disorder characterized primarily by deviant verbalizations has a higher recurrence in relatives of schizophrenic patients than schizophrenia itself. These findings suggest that deviant verbalizations may be more penetrant expressions of schizophrenia susceptibility genes than schizophrenia. This paper reviews the evidence documenting the presence of thought, language and communication disorders in schizophrenic patients and in their first-degree relatives. This familial aggregation potentially implicates genetic factors in the etiology of thought disorder, language anomalies, and communication disturbances in schizophrenia families. We also present two examples of ways in which thought, language and communication disorders can enrich genetic studies, including those involving schizophrenia.

Agrammatism in a case of formal thought disorder: Beyond intellectual decline and working memory deficit

Previous studies have suggested that naming and syntactic deficits in formal thought disorder may be related to global cognitive decline. This article reports the case of a patient, FM, with formal thought disorder schizophrenia who presents disproportionate deficits in receptive and expressive grammar with respect to his intellectual level of functioning. Syntactic and morphologic components of expressive grammar appeared equally impaired. Deficits in language comprehension were observed independently from working memory limitations. FM showed preserved grammaticality judgment, but defective sentence comprehension where semantic context does not provide heuristics for assigning thematic roles, but syntactic knowledge is essential. These atypical results are discussed within a neurodevelopmental aetiological model of formal thought disorder.

Procedural discourse in intellectual disability and dual diagnosis

BACKGROUND

Knowledge of discourse abilities of adults with intellectual disability (ID) and mental illness is limited. The present study examined the procedural discourse skills of two cohorts of adults with ID - one cohort with (n = 7) and one cohort without (n = 7) a psychiatric diagnosis of psychosis.

METHODS

Participants completed the 'dice game', a procedural discourse elicitation procedure that has been used by previous researchers.

RESULTS

Results revealed that while all participants demonstrated an understanding of the task, participants with ID alone were more able to communicate the key elements of the game than the participants in the dual diagnosis group.

CONCLUSIONS

Results of this investigation suggest that individuals with dual diagnosis have difficulties that may relate to previously identified discourse impairments in people with schizophrenia, and this may relate to a larger difficulty in taking into account the listener's needs.

Grammatical processing in schizophrenia: evidence from morphology

Patients with psychiatric disorders such as schizophrenia commonly present with impaired language. Here we investigate language in schizophrenia with a focus on inflectional morphology, using an intensively studied and relatively well-understood linguistic paradigm. Patients with schizophrenia (n=43) and age-matched healthy control subjects (n=42) were asked to produce past tenses of regular (slip), irregular (swim), and novel (plag) English verbs. Patients were impaired at regulars and novels (slipped, plagged), with relative sparing of irregulars (swam), controlling for numerous subject- and item-specific factors (e.g., IQ, phonological complexity). Additionally, patients' thought-disorder scores significantly predicted their performance at regular and novel (but not irregular) past-tense production. The results support grammatical deficits in schizophrenia, with a relative sparing of lexical memory, and suggest that thought disorder may be linked with grammatical impairments in the disorder.

Automated characterization and identification of schizophrenia in writing

Prominent formal thought disorder, expressed as unusual language in speech and writing, is often a central feature of Schizophrenia. Since a more comprehensive understanding of phenomenology surrounding thought disorder is needed, this study investigates these processes by examining writing in Schizophrenia by novel computer-aided analysis. Thirty-six patients with DSM-IV criteria chronic Schizophrenia provided a page of writing (300-500 words) on a designated subject. Writing was examined by automated text categorization and compared with nonpsychiatrically ill individuals, investigating any differences with regards to lexical and syntactical features. Computerized methods used included extracting relevant text features, and utilizing machine learning techniques to induce mathematical models distinguishing between texts belonging to different categories. Observations indicated that automated methods distinguish schizophrenia writing with 83.3% accuracy. Results reflect underlying impaired processes including semantic deficit, independently establishing connection between primary pathology and language.

Overinclusive thought and loosening of associations are not unique to schizophrenia and are produced in Alzheimer's dementia

INTRODUCTION

Bleuler's concept of loosening of associations which he believed epitomised psychotic thinking can manifest as overinclusion (merging of semantic categories) on semantic categorisation tasks. Overinclusion is explained by excessive activation within the semantic memory network to subordinate features with low associative strength. Therefore patients with degradation of subordinate semantic knowledge (e.g., with Alzheimer's Dementia-AD) should not produce overinclusion errors.

METHODS

22 people with schizophrenia and 26 people with AD (nonpsychotic, semantic memory impairment) were compared on a semantic categorisation test, the Category Generation Test (CGT). The CGT involves free-sorting 45 cards of pictured objects from five taxonomic groups (e.g., animals). Overinclusion and underinclusion (subdivision of categories) errors were recorded and the strategies used in generating these abnormal categories were explored qualitatively.

RESULTS

Two-thirds of both groups generated abnormal categories, including frequent overinclusions. Using a semantic probes test, abnormal categorisations could not be attributed to knowledge degradation as this appeared preserved. Qualitatively, the two groups differed in their sorting strategies.

CONCLUSIONS

Loosening of associations is found in nonpsychotic people, who have semantic memory impairments (e.g., AD), using semantic knowledge tasks. However there may be different explanations; atypical semantic categorisation in schizophrenia appears to result from attention to thematic rather than feature-based associations.

Noun-verb ambiguity in chronic undifferentiated schizophrenia

This study investigated noun-verb retrieval patterns of 30 adults with chronic undifferentiated schizophrenia and 67 typical adults, to determine if schizophrenia affected nouns (associated with temporal lobe function) differently from verbs (associated with frontal lobe function). Stimuli were homophonic homographic homonyms, balanced according to frequency of occurrence, where N>V, N<V, or N approximately V. Systematicity effects, in which systematic noun and verb meanings are transparently related (e.g., "drain"), and unsystematic noun and verb meanings appear to be unrelated (e.g., "seal"), were also examined. Adults with schizophrenia overselected nouns, in both phrase and sentence tasks. Typical participants strongly preferred verbs in the phrase task, but nouns in the sentence task. Frequency of occurrence yielded statistically significant effects in control, but not in experimental groups. Effects of systematicity were statistically significant in some, but not all tasks and conditions. Age of typical participants was not significant.

LEARNING OUTCOMES

Readers will be introduced to (a) evidence of noun-verb organization in the brain; (b) evidence of ambiguous noun-verb preference to differentiate the language of schizophrenia from the language of typical adults; and (c) evidence of ambiguous noun-verb preference to differentiate the language of schizophrenia from fluent aphasia.

Metabolic changes in schizophrenia and human brain evolution

BACKGROUND

Despite decades of research, the molecular changes responsible for the evolution of human cognitive abilities remain unknown. Comparative evolutionary studies provide detailed information about DNA sequence and mRNA expression differences between humans and other primates but, in the absence of other information, it has proved very difficult to identify molecular pathways relevant to human cognition.

RESULTS

Here, we compare changes in gene expression and metabolite concentrations in the human brain and compare them to the changes seen in a disorder known to affect human cognitive abilities, schizophrenia. We find that both genes and metabolites relating to energy metabolism and energy-expensive brain functions are altered in schizophrenia and, at the same time, appear to have changed rapidly during recent human evolution, probably as a result of positive selection.

CONCLUSION

Our findings, along with several previous studies, suggest that the evolution of human cognitive abilities was accompanied by adaptive changes in brain metabolism, potentially pushing the human brain to the limit of its metabolic capabilities.

Two new scales of formal thought disorder in schizophrenia

Information provided by patients and respective carers may help to understand formal thought disorder (FTD) in schizophrenia. Two scales, one for patients (FTD-patient) and one for carers (FTD-carer), were constructed to assess pragmatics, cognitive, paralinguistic, and non-verbal aspects of communication. In the first scale the patients themselves assess their verbal communication; in the second scale the carer assesses the speech of the respective patient. Both scales exhibited internal reliability and evidence of good test-retest reliability. Higher total scores on both scales (FTD-patient and FTD-carer) were significantly associated with positive FTD, but not with negative FTD. Principal component analysis of the scales yielded a multidimensional structure. It is suggested that FTD in schizophrenia may be associated with a range of deficits (e.g. pragmatics, lexical activation, working memory, sustained attention). These scales, in conjunction with the clinician's assessment, can provide a more comprehensive picture of FTD in schizophrenia, revealing its dimensions and making it possible to establish associations between symptoms of FTD and neuropsychological, neurophysiologic, and neuroimaging data. In addition, they provide service users' and carers' perspectives for the assessment of communication in schizophrenia.

Formal thought disorder is characterised by impaired lexical access

Recent studies have proposed that difficulty with accessing the lexical-semantic memory store may underpin some of the specific linguistic problems associated with formal thought disorder (FTD). We examined the consistency of name retrieval as an indicator of the ability to access lexical-semantic knowledge in patients with and without marked FTD to see if problems are specific to the former or common to schizophrenic patients in general. A graded naming test was administered on two separate occasions 8-16 weeks apart to 48 participants in three groups: 16 schizophrenic patients with high ratings of FTD, 16 schizophrenic patients with low ratings of FTD and 16 healthy controls. We compared the groups for naming consistency across time and the relationship between naming consistency and specific symptoms of FTD. Both patient groups had impaired naming and this was significantly greater in high than low FTD patients. The high FTD patients showed a profile that differed from both low FTD patients and healthy controls insofar as their naming was inconsistent across time, characteristic of an access disorder. Specifically, the FTD symptoms of derailment, tangentality and incoherence were related to the ability to access the lexical-semantic store. In conclusion, most patients with schizophrenia show an impaired semantic memory store. Nevertheless, FTD is associated with additional lexical-semantic difficulties that are quantitatively different to those seen in patients without FTD, and which may reflect disorganized semantic access.

Schizophrenia and the structure of language: the linguist's view

Patients with schizophrenia often display unusual language impairments. This is a wide ranging critical review of the literature on language in schizophrenia since the 19th century. We survey schizophrenic language level by level, from phonetics through phonology, morphology, syntax, semantics, and pragmatics. There are at least two kinds of impairment (perhaps not fully distinct): thought disorder, or failure to maintain a discourse plan, and schizophasia, comprising various dysphasia-like impairments such as clanging, neologism, and unintelligible utterances. Thought disorder appears to be primarily a disruption of executive function and pragmatics, perhaps with impairment of the syntax-semantics interface; schizophasia involves disruption at other levels. Phonetics is also often abnormal (manifesting as flat intonation or unusual voice quality), but phonological structure, morphology, and syntax are normal or nearly so (some syntactic impairments have been demonstrated). Access to the lexicon is clearly impaired, manifesting as stilted speech, word approximation, and neologism. Clanging (glossomania) is straightforwardly explainable as distraction by self-monitoring. Recent research has begun to relate schizophrenia, which is partly genetic, to the genetic endowment that makes human language possible.

Thought disorder, pragmatic language impairment, and generalized cognitive decline in schizophrenia

BACKGROUND

Schizophrenia is associated with pragmatic language impairment (PLI), a reduced ability to communicate intention in a rule-governed fashion. Two explanations for PLI include that PLI is equivalent to thought disorder and that PLI is secondary to generalized cognitive decline.

OBJECTIVES

The aims of this study were to demonstrate PLI in schizophrenia and to test which of these explanations best accounts for the relationships among thought disorder, PLI, and generalized cognitive decline.

METHOD

Schizophrenia (n=20) and control (n=26) participants provided speech samples that were scored for thought disorder (type-token ratio and Cloze procedure) and PLI [Profile of Pragmatic Impairment in Communication (PPIC)]. Generalized cognitive decline was determined from discrepancies between current and premorbid verbal IQ.

RESULTS

Patients with schizophrenia exhibited significant PLI and generalized cognitive decline. There was no evidence of an association between thought disorder and PLI. Moreover, generalized cognitive decline predicted PLI (r(2)=0.33 to 0.59) but not thought disorder (r(2)=0.02 to 0.06).

CONCLUSIONS

The results conformed to a predicted pattern of associations based on the notion that PLI in schizophrenia is secondary to generalized cognitive decline.

Neural correlates of syntax production in schizophrenia

BACKGROUND

The production of grammatically complex sentences is impaired in schizophrenia. It has been suggested that impaired syntax processing reflects a risk for the disorder.

AIMS

To examine the neural correlates of syntax production in people with schizophrenia using functional magnetic resonance imaging (fMRI).

METHOD

Six patients with schizophrenia and six healthy volunteers spoke about seven Rorschach inkblots for 3 min each while correlates of brain activation were measured with fMRI. Participants produced varying amounts of syntactically simple and complex sentences during each 3 min run. The number of simple and complex sentences was correlated separately with the BOLD contrast.

RESULTS

In the comparison between the control group and the patient group, the number of complex sentences produced was correlated with activation in the posterior portion of the right middle temporal (Brodmann area 21) and left superior frontal (BA10) gyriin the control group but not in the patients.

CONCLUSIONS

The absence of activation in the right posterior temporal and left superior frontal cortex in patients with schizophrenia might contribute to the articulation of grammatically more simple speech in people with this disorder.