Schizophrenia Spectrum Disorders Group Research Articles

Further clarification of cognitive processes of prospective memory in schizophrenia by comparing eye-tracking and ecologically-valid measurements

The aim of this study is to compare ecologically-valid measure (the Cambridge Prospective Memory Test, CAMPROMPT) and laboratory measure (eye-tracking paradigm) in assessing prospective memory (PM) in individuals with schizophrenia spectrum disorders (SSDs). In addition, eye-tracking indices are used to examine the relationship between PM and other cognitive domains in SSDs patients. Initially, the study sample was formed by 32 SSDs patients and 32 healthy control subjects (HCs) who were matched in sociodemographic profile and the performance on CAMPROMPT. An eye-tracking paradigm was employed to examine the differences in PM accuracy and key cognitive processes (e.g., cue monitoring) between the two groups. Additional 31 patients were then recruited to investigate the relationship between PM cue monitoring, other cognitive functions, and the severity of clinical symptoms within the SSDs group. The monitoring of PM cue was reflected in total fixation time and total fixation counts for distractor words. Cognitive functions were assessed using the Chinese version of the MATRICS Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was applied to assess psychopathology. SSDs patients exhibited fewer total fixation counts for distractor words and lower PM accuracy compared to HCs, even though they were priori matched on CAMPROMPT. Correlation analysis within the SSDs group (63 cases) indicated a negative correlation between PM accuracy and PANSS total score, and a positive correlation with working memory and attention/vigilance. Regression analysis within the SSDs group revealed that higher visual learning and lower PANSS total scores independently predicted more total fixation counts on distractor words. Impairment in cue monitoring is a critical factor in the PM deficits in SSDs. The eye-tracking laboratory paradigm has advantages over the ecologically-valid measurement in identifying the failure of cue detection, making it a more sensitive tool for PM deficits in patients with SSDs.

Longitudinal risk of suicide outcomes in people with severe mental illness following an emergency department visit and the effects of suicide prevention treatment

BackgroundIndividuals with severe mental illness (SMI), including bipolar disorder (BD) and schizophrenia-spectrum disorders (SSD), are at high risk for suicide. However, suicide research often excludes individuals with SMI. The current research examined differences in suicide outcomes (i.e., suicide attempt or death) for adults with and without BD and SSD diagnoses following an emergency department (ED) visit and investigated the efficacy of the Coping Long Term with Active Suicide Program (CLASP) intervention in reducing suicide outcomes among people with SMI. Methods1235 adults presenting with recent suicidality were recruited from 8 different EDs across the United States. Using a quasi-experimental, stepped wedge series design, participants were followed for 52-weeks with or without subsequent provision of CLASP. ResultsParticipants in the SSD group and the BD group had significantly shorter time to and higher rate of suicide outcomes than participants with other psychiatric diagnoses in all study phases and in non-CLASP phases, respectively. Participants with BD receiving the CLASP intervention had significantly longer time to suicide outcomes than those not receiving CLASP; these differences were not observed among those with SSD. LimitationsStudy limitations include self-reported psychiatric diagnosis, exclusion of homeless participants, and small sample size of participants with SSD. ConclusionsParticipants with SMI were at higher risk for suicide outcomes than participants with other psychiatric diagnoses. CLASP was efficacious among those participants with BD. Psychiatric diagnosis may be a key indicator of prospective suicide risk. More intensive and specialized follow-up mental health treatment may be necessary for those with SSD.

Personality disorders and schizophrenia spectrum disorders in the Italian forensic psychiatric population: clinical features, pattern of violence and treatment

Starting in 2015, the Residencies for Execution of Security Measures (REMS) became the place of treatment and care for dangerous offenders who were acquitted due to a mental disorder in Italy. Schizophrenia spectrum disorders (SSD) and personality disorders (PD) are the most common psychiatric disorders among REMS patients. This study aimed to identify and describe potential clinical, therapeutic, and criminal-related differences in REMS patients with SSD and PD. A sample of 528 REMS patients extracted from a previous observational retrospective study underwent secondary analysis. The group of PD patients (n = 150) comprised more females (p < 0.001) and had a higher frequency of substance abuse (p < 0.001) than the SSD group (n = 378). The SSD group was more frequently admitted to the REMS due to homicide/attempted homicide (p < 0.001). Among SSD patients, we found a higher recognition of criminal irresponsibility (p < 0.001). Patients with PD were more likely to engage in violent behavior in the REMS than their SSD counterparts (p < 0.001). Patients with SSD were more likely to receive antipsychotic polypharmacy (p < 0.05) and a higher dose of antipsychotics (p < 0.001). These initial results provide empirical evidence to support the need for personalized forensic treatment paths.

Optical Coherence Tomography in Schizophrenia Spectrum Disorders: A Systematic Review and Meta-analysis

BackgroundInner retinal atrophy has been demonstrated in schizophrenia spectrum disorder (SSD) using optical coherence tomography (OCT). This systematic review and meta-analysis investigated the role of contemporary Fourier domain OCT devices in SSD. MethodsMEDLINE, PubMed, Scopus, Embase, PsycInfo, PYSNDEX, World Health Organization, and Cochrane databases were searched from inception until May 2022. All peer-reviewed adult SSD case-control studies using Fourier domain OCT were included. Ocular pathologies known to affect retinal OCT scans were excluded. Search, data appraisal, and summary data extraction were independently performed by 2 authors. ResultsThe review criteria was met by k = 36 studies, with k = 24 studies (1074 cases, 854 controls) suitable for meta-analysis. The SSD group exhibited a thinner global peripapillary retinal nerve fiber layer (−3.26 μm, 95% CI, −5.07 to −1.45, I2 = 64%, k = 21), thinner average macular layer (−7.88 μm, 95% CI, −12.73 to −3.04, I2 = 65%, k = 11), and thinner macular ganglion cell-inner plexiform sublayer (−2.44 μm, 95% CI, −4.13 to −0.76, I2 = 30%, k = 8) compared with the control group. Retinal nerve fiber layer findings remained significant after exclusion of metabolic disease, low quality, outlier, and influential studies. Studies involving eye examinations to exclude eye disease were associated with greater atrophy in SSD. Except for cardiometabolic disease, most studies did not report clinically significant covariate data known to influence retinal thickness. ConclusionsIndividuals with SSD generally exhibited retinal atrophy, possibly paralleling reduced brain volumes documented in clinical imaging. Prospective longitudinal studies that collect clinical data, including various illness phases, and control for confounders will be necessary to evaluate retinal atrophy as a biomarker in SSD.

Association between gut permeability, brain volume, and cognition in healthy participants and patients with schizophrenia spectrum disorder.

The barrier function of the gut is important for many organs and systems, including the brain. If gut permeability increases, bacterial fragments may enter the circulation, giving rise to increased systemic inflammation. Increases in bacterial translocation are reflected in higher values of blood markers, including lipopolysaccharide binding protein (LBP) and soluble cluster of differentiation 14 (sCD14). Some pioneer studies showed a negative association between bacterial translocation markers and brain volumes, but this association remains scarcely investigated. We investigate the effect of bacterial translocation on brain volumes and cognition in both healthy controls and patients with a schizophrenia spectrum disorder (SSD). Healthy controls (n=39) and SSD patients (n=72) underwent an MRI-scan, venipuncture and cognition assessments. We investigated associations between LBP and sCD14 and brain volumes (intracranial volume, total brain volume, and hippocampal volume) using linear regression. We then associated LBP and sCD14 to cognitive function using a mediation analysis, with intracranial volume as mediator. Healthy controls showed a negative association between hippocampal volume and LBP (b=-0.11, p=.04), and intracranial volume and sCD14 (b=-0.25, p=.07). Both markers were indirectly associated with lower cognitive functioning in healthy controls (LBP: b=-0.071, p=.028; sCD14: b=-0.213, p=.052), mediated by low intracranial volume. In the SSD patients, these associations were markedly less present. These findings extend earlier studies suggesting that increased bacterial translocation may negatively affect brain volume, which indirectly impacts cognition, even in this young healthy group. If replicated, this finding stresses the importance of a healthy gut for the development and optimal functioning of the brain. Absence of these associations in the SSD group may indicate that other factors such as allostatic load, chronic medication use and interrupted educational carrier had larger impact and attenuated the relative contribution of bacterial translocation.

Mediation Effects of Social Cognition on the Relationship between Neurocognition and Social Functioning in Major Depressive Disorder and Schizophrenia Spectrum Disorders.

In schizophrenia spectrum disorders (SSD), social cognition mediates the relationship between neurocognition and social functioning. Although people with major depressive disorder (MDD) also exhibit cognitive impairments, which are often prolonged, little is known about the role of social cognition in MDD. Using data obtained through an internet survey, 210 patients with SSD or MDD were selected using propensity score matching based on their demographics and illness duration. Social cognition, neurocognition, and social functioning were evaluated using the Self-Assessment of Social Cognition Impairments, Perceived Deficits Questionnaire, and Social Functioning Scale, respectively. The mediation effects of social cognition on the relationship between neurocognition and social functioning were examined in each group. Invariances of the mediation model across the two groups were then analyzed. The SSD and MDD groups had mean ages of 44.49 and 45.35 years, contained 42.0% and 42.8% women, and had mean illness durations of 10.76 and 10.45 years, respectively. In both groups, social cognition had significant mediation effects. Configural, measurement, and structural invariances across the groups were established. The role of social cognition in patients with MDD was similar to that in SSD. Social cognition could be a common endophenotype for various psychiatric disorders.

Latent Factors of Language Disturbance and Relationships to Quantitative Speech Features.

Quantitative acoustic and textual measures derived from speech ("speech features") may provide valuable biomarkers for psychiatric disorders, particularly schizophrenia spectrum disorders (SSD). We sought to identify cross-diagnostic latent factors for speech disturbance with relevance for SSD and computational modeling. Clinical ratings for speech disturbance were generated across 14 items for a cross-diagnostic sample (N = 334), including SSD (n = 90). Speech features were quantified using an automated pipeline for brief recorded samples of free speech. Factor models for the clinical ratings were generated using exploratory factor analysis, then tested with confirmatory factor analysis in the cross-diagnostic and SSD groups. The relationships between factor scores and computational speech features were examined for 202 of the participants. We found a 3-factor model with a good fit in the cross-diagnostic group and an acceptable fit for the SSD subsample. The model identifies an impaired expressivity factor and 2 interrelated disorganized factors for inefficient and incoherent speech. Incoherent speech was specific to psychosis groups, while inefficient speech and impaired expressivity showed intermediate effects in people with nonpsychotic disorders. Each of the 3 factors had significant and distinct relationships with speech features, which differed for the cross-diagnostic vs SSD groups. We report a cross-diagnostic 3-factor model for speech disturbance which is supported by good statistical measures, intuitive, applicable to SSD, and relatable to linguistic theories. It provides a valuable framework for understanding speech disturbance and appropriate targets for modeling with quantitative speech features.

Symptom Exacerbations of Patients Attending a Community Mental Health Center During the COVID-19 Pandemic.

The aim of this study was to examine the effect of the COVID-19 pandemic on the clinical conditions of the patients with bipolar disorder (BD) and schizophrenia spectrum disorders (SSD) in a community mental health center (CMHC). Symptom exacerbations, emergency service admissions, drug dose increases, additional medication prescriptions, and psychiatric hospitalizations of patients with BD and SSD in the CMHC were evaluated retrospectively. The data from the 1-year prior, 6-months prior, 6-months after the onset and 1-year after the onset of the pandemic were compared. Hospital and CMHC medical records were used for outcomes. Personal and Social Performance (PSP) Scale was used to assess the level of functioning. 107 patients with the diagnosis of BD and 121 patients with the diagnosis of SSD were recruited. In the BD group, there was increase in the frequency of symptom exacerbations (p=0.001) and additional medication prescriptions or increased dose (p=0.007), with decrease in emergency service admissions (p=0.039) during the pandemic. In the patients with SSD, the number of patients with exacerbation of symptoms (p=0.001) and with increased dose or additional medication prescriptions (p=0.004) were higher during the pandemic. There was no increase in the rate of hospitalized patients in the period of first 6 months and first one year. Symptom exacerbations were more frequent in the SSD group with Covid (+) in family (p=0.016). The fact that the hospitalization rates remained the same despite an increase in the acute exacerbations provides info on the role of CMHCs and how mental health system functioned during the pandemic.

Neuropsychological profile of executive functions in autism spectrum disorder and schizophrenia spectrum disorders: a comparative group study in adults

As assessed by numerous neuropsychological tasks, individuals with autism spectrum disorder (ASD) and schizophrenia spectrum disorders (SSDs) have similar impairments related to executive functions (EFs). The neuropsychological profile of these two conditions was examined using the three-component EFs’ framework of Miyake and Friedman (Cogn Psychol 41(1):49-100, 2000). This approach assesses Inhibition (suppression of unwanted and irrelevant information/responses), Updating (use and control of contents of working memory), and Shifting (disengagement between activities or mental tasks) using nine different tasks. In line with previous research, we expected greater performance deficits in ASD in all three components compared to SSD, as well as faster responses for the SSD group. A self-paced task format allowed us to examine whether unlimited time given for a task would lead to better performance. The sample was constituted by the control group (N = 25), ASD group (N = 24), and SSD group (N = 12). Groups did not differ on Inhibition performance. In Updating, individuals with SSD performed poorer than the other groups. As for Shifting, both groups demonstrated poorer performance compared to controls, with the SSD group presenting the greatest difficulties. In terms of reaction time (RT), SSD participants’ RT were the slowest on Inhibition and Shifting tasks. There was a positive correlation between performance and time spent on Inhibition and Shifting only for the SSD group, which demonstrates that their performance improves when there are no time constraints. Our work provides a better understanding of spared and impaired EFs, which could be useful for designing strategies aimed at improving specific EFs in each group.

Comparison of the Phenomenology of Hallucination and Delusion Characteristics in People Diagnosed With Borderline Personality Disorder and Schizophrenia.

Hallucinations and delusions in borderline personality disorder (BPD) are understudied. The authors explore the phenomenology of multisensory hallucinations and delusions in individuals with BPD and compare them to those in individuals with schizophrenia spectrum disorders (SSD). Clinical psychopathology was also explored. Eighty-nine adults participated and were categorized into four groups: BPD with voices, BPD without voices, SSD with high BPD traits, and SSD with low BPD traits. Among individuals with BPD, 81% reported visual and tactile hallucinations, 75% reported olfactory hallucinations, and 94% experienced delusions. When comparing BPD with and without voices, there were no significant differences in nonpsychotic psychopathology. Slight differences were found when hallucinations in BPD were compared with hallucinations in SSD, but overall the experiences were similar across diagnoses. The BPD group also reported significantly higher rates of paranoia/suspiciousness and delusions of guilt than the SSD group. Multisensory hallucinations and delusions occur in BPD and should be explored when treating people with BPD.

Validation of the Italian version of the Davos Assessment of Cognitive Biases Scale (DACOBS) in a sample of schizophrenia spectrum disorder patients and healthy controls.

Recently two instruments were developed to address the study of the cognitive biases in schizophrenia spectrum disorders (SSD): the Cognitive Biases Questionnaire for Psychosis (CBQ-P) and the Davos Assessment of Cognitive Biases Scale (DACOBS). Aim of this study was to validate the Italian version of the DACOBS. We investigated factor structure, reliability, discriminative and convergent validity of the instrument by comparing to the CBQ-P in an Italian sample of 102 patients diagnosed with SSD and 330 healthy controls (HC), matched by age, education and gender. The second-order seven-factor solution provided the best results among the four models tested. Reliability proved to be very satisfactory, with ω coefficient ranged from 0.75 for Jumping to conclusions to 0.89 for Safety Behavior. The Italian version of DACOBS could discriminate psychosis from HC (Wilks' Lambda=0.64, F=34.284, p<0.001; h2=0.364). All seven DACOBS subscales were significantly correlated with the CBQ-P subscales (total sample: r=0.331-0.707; SSD group: r=0.424-0.735; HC group: r=0.177-0.460). The Italian version of DACOBS is a valid instrument for measuring cognitive biases for patients with psychosis, confirming previous results regarding the psychometric properties of the tool.

Metabolic disturbances, hemoglobin A1c, and social cognition impairment in Schizophrenia spectrum disorders

Social cognitive impairments are core features of schizophrenia spectrum disorders (SSD) and are associated with greater functional impairment and decreased quality of life. Metabolic disturbances have been related to greater impairment in general neurocognition, but their relationship to social cognition has not been previously reported. In this study, metabolic measures and social cognition were assessed in 245 participants with SSD and 165 healthy comparison subjects (HC), excluding those with hemoglobin A1c (HbA1c) > 6.5%. Tasks assessed emotion processing, theory of mind, and social perception. Functional connectivity within and between social cognitive networks was measured during a naturalistic social task. Among SSD, a significant inverse relationship was found between social cognition and cumulative metabolic burden (β = −0.38, p < 0.001) and HbA1c (β = −0.37, p < 0.001). The relationship between social cognition and HbA1c was robust across domains and measures of social cognition and after accounting for age, sex, race, non-social neurocognition, hospitalization, and treatment with different antipsychotic medications. Negative connectivity between affect sharing and motor resonance networks was a partial mediator of this relationship across SSD and HC groups (β = −0.05, p = 0.008). There was a group x HbA1c effect indicating that SSD participants were more adversely affected by increasing HbA1c. Thus, we provide the first report of a robust relationship in SSD between social cognition and abnormal glucose metabolism. If replicated and found to be causal, insulin sensitivity and blood glucose may present as promising targets for improving social cognition, functional outcomes, and quality of life in SSD.

Oppel – Kundt illusion manifestation among people with schizophrenia spectrum disorders

IntroductionVarious studies have reported differences in early visual processing, gain control and integration for patients with schizophrenia spectrum disorders (SSD). However, Oppel – Kundt (OK) illusion is not studied well enough among subjects affected by SSD. We decided to study the illusion to get more insights in visual perception for individuals with SSD.ObjectivesTo investigate the OK illusion manifestation among people with SSD.MethodsIn the prospective study were included 15 patients, who were diagnosed with SSD and 15 matched comparison group (CG) without any mental, neurological diseases or visual impairment. OK figures used in the experiments consisted of three white spots presented horizontally against the black background. We used 3 different types of distractor stimuli – either straight one or two-sided line or circle. Using computerized equipment in OK figures the subjects were asked to adjust the unfilled part of the stimulus to be equal in length to the filled (referential) one. ANOVA, T-test and post hoc Bonferroni correction were used for statistical analysis.ResultsPeople with SSD tended to make bigger mistakes when evaluating OK figures with the statistical difference which was the most eminent for the subgroup of individuals affected by paranoid schizophrenia. The manifestation of the illusion in the SSD group was contrariwise (respectively to zero point) to the CG group.ConclusionsOK illusion tended to manifest stronger for patients with SSD, this tendency was mostly expressed for the patients diagnosed with paranoid schizophrenia. The manifestation of OK illusion among persons with SSD was diametrically opposite to that seen for the healthy individuals.DisclosureNo significant relationships.

Impact of early onset of chronic physical multimorbidities on schizophrenia spectrum disorder treatment outcome

IntroductionDespite of the heightened risks and burdens of physical comorbidities across the entire schizophrenia spectrum disorders (SSD), relatively little is known about physical multimorbidity (CPM) in this population. The study’s main objective was to explore the differences in the CPM prevalence between SSD patients and the general population (GEP).ObjectivesThe primary outcome was to explore the difference in CPM prevalence in the younger SSD and GEP groups (&lt;35 years).The secondary outcome was the number of psychiatric readmissions.MethodsThis nested cross-sectional study enrolled 343 SSD patients and 620 GEP participants.ResultsYounger SSD patients had more than three-fold higher odds for CPM than GEP. We also demonstrated an association between the presence of CPM and the number of psychiatric admissions in the SSD population independently of possible confounders. We did not observe significant interaction of CPM and age in the prediction of clozapine use. Younger women with SSD had statistically significant, almost four-fold higher odds of CPM than women from GEP.ConclusionsThis study suggests that women with SSD are at increased physical comorbidity risk compared to men, particularly early in the course of psychiatric illness. Our results highlight the importance of addressing physical health from the first contact with a mental health service to preserve general health, and provide the best possible treatment outcome. Treatment of SSD must be customized to meet the needs of patients with different physical multimorbidity patterns.DisclosureNo significant relationships.

Differentiating autoimmune encephalitis from schizophrenia spectrum disorders among patients with first-episode psychosis

BackgroundAlthough differential diagnosis between autoimmune encephalitis and schizophrenia spectrum disorders is crucial for a good outcome, the psychiatric symptoms that distinguish these two conditions have not been identified even though psychiatric symptoms are often the main manifestation of autoimmune encephalitis. Also, there are many situations in clinical psychiatry in which laboratory testing and imaging studies are not available. Because no comparative study of the psychiatric symptoms between these two conditions has been carried out, we explored diagnostically useful psychiatric symptoms in a retrospective case-control study. MethodsWe recruited 187 inpatients with first-episode psychosis who were admitted to our psychiatric unit and categorized them into two groups: the autoimmune encephalitis group (n = 10) and the schizophrenia spectrum disorders group (n = 177). Differences in the symptoms and signs between the two groups were investigated. ResultsSchneider's first-rank symptoms (e.g., verbal commenting hallucinations and delusional self-experience) were observed only in the schizophrenia spectrum disorders group, whereas altered perception was found more frequently in the autoimmune encephalitis group. Functional status was worse in the autoimmune encephalitis group, and neurological and neuropsychological signs were revealed almost exclusively in this group. A history of mental illness was more frequently reported in the schizophrenia spectrum disorders group than in the autoimmune encephalitis group. ConclusionsThe psychiatric symptoms, i.e., Schneider's first-rank symptoms and altered perception, together with neurological and neuropsychological signs, functional status, and past history, may help clinicians accurately differentiate these two conditions among patients with first-episode psychosis.

Premorbid characteristics of patients with DSM-IV psychotic disorders

IntroductionPsychotic disorder not otherwise specified (PNOS) is considered part of the psychosis spectrum, together with schizophrenia spectrum disorders (SSD) and psychotic bipolar spectrum disorders (PBD). The atypical clinical presentations of PNOS conditions may lead to uncertainty regarding treatment choices and expected outcomes. PNOS is understudied, and little is known about patients' premorbid characteristics including premorbid adjustment, prevalence of early cannabis use and childhood trauma. Knowledge about early illness phases can increase our understanding of this diagnostic group. MethodsWe included 1099 participants from the Norwegian TOP-study; 688 with narrow SSD diagnoses (schizophrenia, schizoaffective disorder, schizophreniform disorder), 274 with PBD (psychotic bipolar 1 and bipolar NOS) and 137 with PNOS diagnosed with the SCID-I for DSM-IV. Participants were assessed with the Premorbid Adjustment Scale (PAS) divided into the areas of premorbid academic and social functioning. We obtained information on age at first exposure to cannabis and use of cannabis before the age of 16. The participants also provided information regarding early traumatic experiences using the Childhood Trauma Questionnaire (CTQ). ResultsParticipants with PNOS and SSD had poorer premorbid academic functioning than those with PBD (F2, 1029 = 7.81, p < 0.001, pη2 = 0.015). Premorbid social adjustment was significantly worse in the SSD group compared to the PBD group (F2, 1024 = 3.10, p = 0.045, pη2 = 0.006), with PNOS in the middle position. Significantly more of the participants with PNOS (17.5%) and SSD (11.5%) used cannabis before the age of 16 compared with PBD (5.3%, Wald χ2 = 6.86, p = 0.03). There were no significant differences between the three groups regarding mean CTQ scores or in the proportion of participants who had experienced at least one type of childhood adversity. ConclusionsParticipants with PNOS appear as more similar to participants with SSD than to those with PBD regarding early premorbid adjustment and early cannabis use. The results indicate that many conditions classified as PNOS have functional impairments and problematic substance use from an early age. The prevalence of childhood adversities are high in all three groups.

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

IntroductionDeficits 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. ObjectiveThe 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. MethodsThirty-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). ResultsResults 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. DiscussionOur 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.

A transdiagnostic meta-analysis of physical and social Anhedonia in major depressive disorder and schizophrenia spectrum disorders

Introduction: Anhedonia is a transdiagnostic construct conceptualized as physical or social, however, the extent to which these subtypes differ across psychotic and mood pathology remains poorly understood. We aimed to quantify the severity of physical and social anhedonia across Major Depressive Disorder (MDD) and Schizophrenia Spectrum Disorder (SSDs).Methods: We conducted meta-analyses of the Chapman Physical and Social Anhedonia Scales (PAS;SAS). We reviewed data from participants with MDD, and SSDs separately.Results: Our first meta-analysis (n = 8 studies, 409 participants) with MDD revealed elevated SAS and PAS in MDD compared to controls. Within-group differences were not significant. Depressive symptom severity moderated the between-group effect of PAS. Our second meta-analysis (n = 44 studies, 3352 participants) revealed elevated SAS and PAS in SSDs compared to controls. We detected a moderate difference between the SAS and PAS within the SSD group. Age moderated within-group differences of SAS and PAS.Discussion: People with SSD or MDD experience elevated SAS and PAS compared to controls. People with SSDs endorse greater challenges experiencing social rewards relative to physical rewards. People with MDD experience social and physical rewards similarly. The moderating role of depressive symptoms in MDD suggests that physical anhedonia is more state-like than social anhedonia.

Thalamocortical dysrhythmia in patients with schizophrenia spectrum disorder and individuals at clinical high risk for psychosis.

Thalamocortical dysrhythmia (TCD) is a model characterized by abnormal resting-state thalamic oscillatory patterns where the alpha rhythm is replaced by cross-frequency coupling of low- and high-frequency rhythms. Although disrupted thalamic function is a suggested important pathophysiological mechanism underlying schizophrenia, knowledge regarding the TCD model in schizophrenia spectrum disorder (SSD) patients and individuals at clinical high risk (CHR) for psychosis is limited. A total of 169 SSD patients, 106 individuals at CHR for psychosis, and 105 healthy controls (HCs) underwent resting-state electroencephalography recordings. We performed mean global field power (MGFP) spectral analysis between 1 and 49 Hz as well as source-level theta phase-gamma amplitude coupling (TGC) analysis and compared resting-state oscillatory patterns across groups. Correlations between altered TGC values and psychotic symptom severity in the patient group were investigated. Spectral MGFP of low- and high-frequencies was larger in the SSD and CHR groups than in the HC group. The TGC of SSD patients was greater than that of HCs in the right frontal, right parietal, and left and right limbic lobes. Greater TGC in the right frontal and limbic lobes was associated with positive symptom severity in SSD patients. However, TGC in the CHR group was comparable to that in the HCs and was smaller than that in the SSD group in widespread cortical regions. The TCD pattern may be apparent after frank psychotic disorder onset in tandem with overt positive symptoms. A psychosis-risk state without overt psychotic symptoms could be characterized by abnormally increased low- and high-frequency activities with relatively preserved TGC.

Ectodermal disturbance in development shared by anorexia and schizophrenia may reflect neurodevelopmental abnormalities.

Minor physical abnormalities (MPA) are subtle dysmorphic features of bodily structures that have little or no impact on function. Most MPA develop during the first gestational trimester and are considered as important indicators of neuroectodermal deficiencies emerging during early brain development. A higher frequency of MPA was confirmed in schizophrenia patients and their relatives, when compared to controls. These findings are consistent with the neurodevelopmental model of schizophrenia. A neurodevelopmental component amongst other risk factors has also been recently proposed for anorexia nervosa (AN). The current study aimed to assess MPA frequency in adolescent inpatients with either schizophrenia spectrum disorders (SSD) or AN as compared to healthy controls (HC). The Waldrop Scale was used for assessing MPA. The mean MPA total score and mean head subscore was significantly higher in both test groups than in HC. There were no statistically significant differences between SSD and AN groups. The MPA profile (not frequency) was similar in all three groups. This finding is consistent both with widely acknowledged neurodevelopmental schizophrenia hypothesis as well as with more recent neurodevelopmental model of AN. Nevertheless, the findings should not be overgeneralized and further studies are warranted.