Metaphor Comprehension in Schizophrenic Patients

On the specificity of figurative language comprehension impairment in schizophrenia and its relation to cognitive skills but not psychopathological symptoms - Study on metaphor, humor and irony

People with schizophrenia have difficulty understanding figurative expressions, such as metaphors, humor or irony. The present study investigated the specificity of figurative language impairment in schizophrenia and its relation with cognitive and psychotic symptoms. It included 54 schizophrenia and 54 age and sex-matched healthy subjects who performed a cognitive screening (ACE-III) and figurative language comprehension task consisting of 60 short stories with three types of endings: a figurative one and its literal and an absurd (meaningless) counterparts. Each figurative domain - metaphor, humor, irony - was split into two sub-domains, i.e., conventional and novel metaphors, intended-to-be-funny and social-norm-violation jokes, simple irony and critical sarcasm, respectively. The main findings are: i) in schizophrenia, figurative language deficit manifests itself in each domain; ii) the most pronounced subdomain-specific impairment has been found for novel vs conventional metaphors and irony vs sarcasm; iii) altered figurative language comprehension was related to diminished cognitive abilities but not to psychopathology symptoms (PANSS) or other clinical characteristics. This may suggest that figurative language impairment, as a specific part of communication deficit, may be regarded as an essential characteristic of schizophrenia, related to primary cognitive deficits but independent of psychopathology.

Language and communication rehabilitation in patients with schizophrenia: A narrative review

Language impairments often appear in patients with schizophrenia and are potential targets for rehabilitation. Clinical practice and research should be intimately connected. The aim was to perform a narrative review of the assessment and intervention tools that have been used for the rehabilitation of schizophrenia patients with language and communication impairments. Two types of tools, general and specific, were developed for both purposes. General tools include the Positive and Negative Syndrome Scale for assessment, and the Integrated Psychological Therapy for intervention. The specific tools used to evaluate language and communication impairments include the Scale for the Assessment of Thought, Language and Communication, the Formal Thought Disorder scales (for caregivers and patients), and the Thought and Language Disorder scale. The most recent language-specific intervention tools include the Cognitive Pragmatic Treatment, Conecta-2, Let's talk! Multimodal Speech-Gesture training, Speech Therapy Intervention Group, and PragmaCom. These tools primarily involve psychopathology/psychiatry, psychology, linguistics, speech and language therapy, and nursing. In conclusion, a wide range of assessment and intervention tools are available for the rehabilitation of language and communication impairments associated with schizophrenia. An integrative and interdisciplinary approach should always be considered for rehabilitation of language and communication in patients with schizophrenia throughout their lifetime.

Multimodal speech-gesture training in patients with schizophrenia spectrum disorder: Effects on quality of life and neural processing

Dysfunctional social communication is one of the most stable characteristics in patients with schizophrenia spectrum disorder (SSD) that severely affects quality of life. Interpreting abstract speech and integrating nonverbal information is particularly affected. Considering the difficulty to treat communication dysfunctions with usual intervention, we investigated the possibility to apply a multimodal speech-gesture (MSG) training. In the MSG training, we offered 8 sessions (60 min each) including perceptive and expressive tasks as well as meta-learning elements and transfer exercises to 29 patients with SSD. In a within-group crossover design, patients were randomized to a TAU-first (treatment as usual first, then MSG training) group (N = 20) or a MSG-first (MSG training first, then TAU only) group (N = 9), and were compared to healthy controls (N = 17). Outcomes were quality of life and related changes in the neural processing of abstract speech-gesture information, which were measured pre-post training through standardized psychological questionnaires and functional Magnetic Resonance Imaging, respectively. Pre-training, patients showed reduced quality of life as compared to controls but improved significantly during the training. Strikingly, this improvement was correlated with neural activation changes in the middle temporal gyrus for the processing of abstract multimodal content. Improvement during training, self-report measures and ratings of relatives confirmed the MSG-related changes. Together, we provide first promising results of a novel multimodal speech-gesture training for patients with schizophrenia. We could link training induced changes in speech-gesture processing to changes in quality of life, demonstrating the relevance of intact communication skills and gesture processing for well-being.

Using the Structure of Evaluative Components as a basis for comparing the oral narratives of schizophrenics and healthy individuals

In this study, evaluative language in narratives of 15 healthy and 15 schizophrenic females was compared using the Structure of Evaluative Components. The two groups were matched for chronological age and socioeconomic status. A movie named "The Pear Film" ( http://chafe.faculty.linguistics.ucsb.edu/pearfilm.htm ) was used to elicit the narratives. The Goal evaluative component in the schizophrenic population and the Ownership in healthy individuals were used more than other components within the narratives of each respective group. Significant differences (Mann-Whitney and t-test) between the two groups in using evaluative components were determined using statistical analysis. In general, patients used less evaluative components in their narratives compared to healthy participants and as per specific components, healthy subjects utilized five evaluative components more than patients, which was found to be a significant difference; Goal, Assumption, Ownership, Metaphor, and Causality were those five components. These findings confirm that the ability to use evaluative language in schizophrenia is reduced.

Altered Brain Criticality in Schizophrenia: New Insights From Magnetoencephalography

Schizophrenia has a complex etiology and symptomatology that is difficult to untangle. After decades of research, important advancements toward a central biomarker are still lacking. One of the missing pieces is a better understanding of how non-linear neural dynamics are altered in this patient population. In this study, the resting-state neuromagnetic signals of schizophrenia patients and healthy controls were analyzed in the framework of criticality. When biological systems like the brain are in a state of criticality, they are thought to be functioning at maximum efficiency (e.g., optimal communication and storage of information) and with maximum adaptability to incoming information. Here, we assessed the self-similarity and multifractality of resting-state brain signals recorded with magnetoencephalography in patients with schizophrenia patients and in matched controls. Schizophrenia patients had similar, although attenuated, patterns of self-similarity and multifractality values. Statistical tests showed that patients had higher values of self-similarity than controls in fronto-temporal regions, indicative of more regularity and memory in the signal. In contrast, patients had less multifractality than controls in the parietal and occipital regions, indicative of less diverse singularities and reduced variability in the signal. In addition, supervised machine-learning, based on logistic regression, successfully discriminated the two groups using measures of self-similarity and multifractality as features. Our results provide new insights into the baseline cognitive functioning of schizophrenia patients by identifying key alterations of criticality properties in their resting-state brain data.

Neural Basis of Speech-Gesture Mismatch Detection in Schizophrenia Spectrum Disorders

Patients with schizophrenia spectrum disorders (SSD) exhibit an aberrant perception and comprehension of abstract speech-gesture combinations associated with dysfunctional activation of the left inferior frontal gyrus (IFG). Recently, a significant deficit of speech-gesture mismatch detection was identified in SSD, but the underlying neural mechanisms have not yet been examined. A novel mismatch-detection fMRI paradigm was implemented manipulating speech-gesture abstractness (abstract/concrete) and relatedness (related/unrelated). During fMRI data acquisition, 42 SSD patients (schizophrenia, schizoaffective disorder, or other non-organic psychotic disorder [ICD-10: F20, F25, F28; DSM-IV: 295.X]) and 36 healthy controls were presented with short video clips of an actor reciting abstract or concrete sentences accompanied by either a semantically related or unrelated gesture. Participants indicated via button press whether they perceived each gesture as matching the speech content or not. Speech-gesture mismatch detection performance was significantly impaired in patients compared to controls. fMRI data analysis revealed that patients showed lower activation in bilateral frontal areas, including the IFG for all abstract > concrete speech-gesture pairs. In addition, they exhibited reduced engagement of the right supplementary motor area (SMA) and bilateral anterior cingulate cortices (ACC) for unrelated > related stimuli. We provide first evidence that impaired speech-gesture mismatch detection in SSD could be the result of dysfunctional activation of the SMA and ACC. Failure to activate the left IFG disrupts the integration of abstract speech-gesture combinations in particular. Future investigations should focus on brain stimulation of the SMA, ACC, and the IFG to improve communication and social functioning in SSD.

On the Role of Bilateral Brain Hypofunction and Abnormal Lateralization of Cortical Information Flow as Neural Underpinnings of Conventional Metaphor Processing Impairment in Schizophrenia: An fMRI and EEG Study

Figurative language processing (e.g. metaphors) is commonly impaired in schizophrenia. In the present study, we investigated the neural activity and propagation of information within neural circuits related to the figurative speech, as a neural substrate of impaired conventional metaphor processing in schizophrenia. The study included 30 schizophrenia outpatients and 30 healthy controls, all of whom were assessed with a functional Magnetic Resonance Imaging (fMRI) and electroencephalography (EEG) punchline-based metaphor comprehension task including literal (neutral), figurative (metaphorical) and nonsense (absurd) endings. The blood oxygenation level-dependent signal was recorded with 3T MRI scanner and direction and strength of cortical information flow in the time course of task processing was estimated with a 64-channel EEG input for directed transfer function. The presented results revealed that the behavioral manifestation of impaired figurative language in schizophrenia is related to the hypofunction in the bilateral fronto-temporo-parietal brain regions (fMRI) and various differences in effective connectivity in the fronto-temporo-parietal circuit (EEG). Schizophrenia outpatients showed an abnormal pattern of connectivity during metaphor processing which was related to bilateral (but more pronounced at the left hemisphere) hypoactivation of the brain. Moreover, we found reversed lateralization patterns, i.e. a rightward-shifted pattern during metaphor processing in schizophrenia compared to the control group. In conclusion, the presented findings revealed that the impairment of the conventional metaphor processing in schizophrenia is related to the bilateral brain hypofunction, which supports the evidence on reversed lateralization of the language neural network and the existence of compensatory recruitment of alternative neural circuits in schizophrenia.

Functional anatomy of idiomatic expressions

Idiomatic expressions (IE) are groups of words whose meaning is different from the sum of its components. Neural mechanisms underlying their processing are still debated, especially regarding lateralization, main structures involved, and whether this neural network is independent from the spoken language. To investigate the neural correlates of IE processing in healthy Spanish speakers.Twenty one native speakers of Spanish were asked to select one of 4 possible meanings for IE or literal sentences. fMRI scans were performed in a 3.0T scanner and processed by SPM 12 comparing IE vs. literal sentences. Laterality indices were calculated at the group level. IE activated a bilateral, slightly right-sided network comprising the pars triangularis and areas 9 and 10. In the left hemisphere (LH): the pars orbitalis, superior frontal, angular and fusiform gyrus. In the right hemisphere (RH): anterior insula, middle frontal, and superior temporal gyrus. This network reveals the importance of the RH, besides traditional LH areas, to comprehend IE. This agrees with the semantic coding model: the LH activates narrow semantic fields choosing one single meaning and ignoring others, and the RH detects distant semantic relationships, activating diffuse semantic fields. It is also in line with the configuration hypothesis: both meanings, literal and figurative, are executed simultaneously, until the literal meaning is definitively rejected and the figurative one is accepted. Processing IE requires the activation of fronto-temporal networks in both hemispheres. The results concur with previous studies in other languages, so these networks are independent from the spoken language. Understanding these mechanisms sheds light on IE processing difficulties in different clinical populations and must be considered when planning resective surgery.

Metaphor Comprehension in Individuals with Autism Spectrum Disorder: Core Language Skills Matter

Poor metaphor comprehension was considered a hallmark of autism spectrum disorder (ASD), but recent research has questioned the extent and the sources of these difficulties. In this cross-sectional study, we compared metaphor comprehension in individuals with ASD (N = 29) and individuals with typical development (TD; N = 31), and investigated the relationship between core language and metaphor comprehension. Individuals with ASD showed more difficulty but also a more variable performance in both metaphor and literal items of the task used than individuals with TD did. This indicates that core language ability accounts for metaphor comprehension and should be considered in future research and interventions aiming to improve metaphor comprehension in individuals with ASD.

Familiarity, empathy and comprehension of metaphors in patients with borderline personality disorder

Research on figurative language has a long tradition in psychiatry, as it is employed in psychotherapy and its (mis)comprehension plays a substantial role in differential diagnostics of schizophrenic spectrum disorders. Although often associated with empathy and mentalization, it has never been addressed in borderline personality disorder (BPD). Therefore, this study investigated metaphor comprehension and its relationship to cognitive and affective empathy in 20 patients with BPD and 20 matched healthy controls who completed a metaphor task comprising conventional metaphors (CM), novel metaphors (NM), meaningless stimuli (MS), and a rating scale of familiarity, a factor known to influence performance. For cognitive and affective empathy, the interpersonal reactivity index was applied. At first patients with BPD seemed to have significantly more problems in comprehending CM, but not NM or MS, and were less familiar with CM. When familiarity with the stimulus was controlled, this difference disappeared. As for empathy, only fantasy was positively related to familiar CM beyond borderline symptoms. Results indicate that the comprehension of novel metaphorical meaning is preserved in patients with BPD.

A leopard cannot change its spots: A novel pragmatic account of concretism in schizophrenia

Concretism is a well-known feature of schizophrenia, tracing back to the early descriptions of the disease and commonly associated with the literal interpretation of figurative expressions such as proverbs, metaphors, and idioms. However, figurative expressions are not all alike in terms of linguistic and pragmatic processes. Determining if some figurative types are more impaired than others and if the type of task affects the performance constitutes an open issue with implications for the description of the clinical profile and for treatment. We run a fine-grained assessment of figurative language comprehension by comparing 47 patients with schizophrenia and 39 controls in three figurative types (idioms, metaphors, proverbs) presented in two response formats (multiple-choice, verbal-explanation), considering also the role of cognitive and clinical variables and the impact on quality of life. Mixed-effects models analysis revealed that: i) patients performed worse than controls across figurative types and response formats, indicating a diffuse impairment; ii) there is an interplay of figurative type and response format, which makes verbal-explanation of proverbs especially challenging; iii) in patients, problems in figurative language are largely connected with formal thought disorder and global IQ. Moreover, multiple-choice of metaphors was associated with patients' quality of life. This study offers a novel account of concretism, framed in pragmatics and figurative language processing. Adopting this perspective allowed us to describe the nuances of concretism, which areas in the figurative domain are especially challenging for patients and which ones capture differences in functioning, in order to guide intervention programs and integration in society.

A Multimodal Speech-Gesture Training Intervention for Patients With Schizophrenia and Its Neural Underpinnings - the Study Protocol of a Randomized Controlled Pilot Trial

Dysfunctional social communication is one of the most stable characteristics in patients with schizophrenia that also affects quality of life. Interpreting abstract speech and integrating nonverbal modalities is particularly affected. Considering the impact of communication on social life but failure to treat communication dysfunctions with usual treatment, we will investigate the possibility to improve verbal and non-verbal communication in schizophrenia by applying a multimodal speech-gesture training (MSG training). Here we describe the newly developed MSG training program and the study design for the first clinical investigation. The intervention contains perceptive rating (match/mismatch of sentence and gesture) and memory tasks (n-back tasks), imitation and productive tasks (e.g., SG fluency-similar to verbal fluency where words are accompanied by gesture). In addition, we offer information about gesture as meta-learning element as well as homework for reasons of transfer to everyday life as part of every session. In the MSG training intervention, we offer eight sessions (60 min each) of training. The first pilot study is currently conducted as a single-center, randomized controlled trial of speech-gesture intervention versus wait-list control with a follow-up. Outcomes are measured through pre-post-fMRI and standardized psychological questionnaires comparing two subject groups (30 patients with schizophrenia and 30 healthy controls). Patients and healthy controls are randomized in two intervention groups (with 20 being in the wait-training group and 10 in the training-follow-up group). With our study design we will be able to demonstrate the beneficial effect of the MSG training intervention on behavioral and neural levels.

CLINICAL TRIAL REGISTRATION

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Metaphor Processing Dysfunctions in Schizophrenia Patients With and Without Substance Use Disorders

BACKGROUND

Patients with schizophrenia have difficulties comprehending metaphors, which significantly impedes communication. However, this topic has not been thoroughly studied in people with a dual diagnosis. On this basis, we formulated two research aims: a) to compare the ability to comprehend metaphors in schizophrenia patients without (SZ) and with substance use disorder (SZ-SUD) and b) to determine the relationship between the processing of metaphorical content and the severity of psychopathological symptoms in both clinical groups.

METHODS

A total of 40 individuals with SZ and 40 individuals with SZ-SUD took part in the study. The control group was composed of 40 individuals without a psychiatric or neurological diagnosis. Four subtests from the Right Hemisphere Language Battery (Picture Metaphor Test, Written Metaphor Test, Picture Metaphor Explanation Test, Written Metaphor Explanation Test) were used to measure the ability to understand and explain metaphors.

RESULTS

Both groups of individuals with schizophrenia (SZ and SZ-SUD) scored lower than individuals from the control group on all tests of metaphor processing. However, no differences were observed between the two clinical groups. SZ-SUD patients had better results for Picture Metaphor Explanation than for Written Metaphor Explanation. Negative symptoms were found to be significant predictors of difficulties with understanding and explaining metaphors.

CONCLUSION

Individuals with schizophrenia, regardless of their substance use disorder (SUD) status, exhibit impaired metaphorical content processing. SUD in schizophrenia is not associated with significant impairments in understanding and explaining metaphorical content. Moreover, impairments in processing metaphorical content are associated with more severe negative symptoms of schizophrenia.

Evidence for gesture-speech mismatch detection impairments in schizophrenia

Patients with schizophrenia suffer from impairments in the perception and production of gestures. The extent to which patients can access the semantic association between speech and co-verbal gestures in concrete or abstract/metaphorical meaning contexts is unknown. We investigated 1) how patients differ from controls in gesture matching performance, 2) how performance differs in the context of abstract versus concrete meaning, and 3) whether formal thought disorder (FTD) symptom severity predicts task impairment. Forty-five patients with schizophrenia spectrum disorders (two subgroups, "mild" and "severe") took part in this study. Participants were presented with video clips, each showing an actor saying a sentence while producing a gesture. Sentences contained either concrete or abstract/metaphorical information, and the accompanying gesture was either semantically related or unrelated to the sentence. Participants indicated via button press whether the gesture matched the content of the verbal utterance. Both patient subgroups demonstrated reduced performance in all comparisons. A significant interaction was found between patient subgroup and sentence abstractness. Task performance was worst for patients with severe positive FTD symptomatology in the abstract condition, while there were no patient subgroup differences in the concrete condition. These data shed new light on gesture-speech mismatch detection impairments in schizophrenia.

Social Cognition Analyzer Application-A New Method for the Analysis of Social Cognition in Patients Diagnosed With Schizophrenia

Introduction: Because of the importance of the assessment of social cognitive impairments in schizophrenia in clinical settings, a new computer application called SCAN (Social Cognition Analyzer applicatioN) was developed. Our first aim was to examine if patients diagnosed with schizophrenia could be differentiated from healthy individuals based on the results of SCAN, taking into consideration both response rates and response times. Our second aim was to create Scanalizer, as part of SCAN, to produce social cognitive profiles of individual patients. Materials and Methods: 86 patients (SG) and 101 healthy participants (CG) were examined with SCAN. The domains were: ToM, irony, metaphor, emotion perception from prosody and social perception. SCAN displayed the tasks, recorded the answers and the response times. For the differentiation of the two groups a two-dimensional scatter plot was used. For the graphical presentation of the social cognitive profile of patients, the calculation of the distributions of CG's results was made with Kolmogorov-Smirnov Goodness-of-fit Test and with the sum of squared residuals (SSR). Results: We found that the SG's response rates were significantly lower and the SG's response times were significantly slower compared to the CG in every condition. With the two-dimensional comparison of the summary response rates and the summary response times of the participants, the SG could be differentiated from the CG and this differentiation worked irrespective of age and education. For the graphical representation of social cognitive functions of patients, distributions of the results of the CG were calculated. We found normal distributions in the response times of all conditions and in the response rates of the ToM condition. In the low-end tail of the irony condition, and in the metaphor, social perception and emotional prosody conditions, power-law distributions were found. We also found that the summary response rates of the lowest performing 10% of the CG was in the same range as the summary response rates of all examined patients. Discussion: Scanalizer enables clinicians to measure and analyse social cognitive profiles of patients diagnosed with schizophrenia. Moreover, SCAN could also be used to detect social cognitive disabilities of vulnerable individuals.