Using transcranial alternating current stimulation to enhance working memory skills in youths with 22q11.2 deletion syndrome: A randomized double-blind sham-controlled study.

Abnormal cognitive development, particularly working memory (WM) deficits, is among the first apparent manifestations of psychosis. Yet, cognitive impairment only shows limited response to current pharmacological treatment. Alternative interventions to target cognition are highly needed in individuals at high risk for psychosis, like carriers of 22q11.2 deletion syndrome (22q11.2DS). Here we applied theta-tuned transcranial alternating current stimulation (tACS) between frontal and temporal regions during a visual WM task in 34 deletion carriers. We conducted a double-blind sham-controlled study over three consecutive days. The stimulation parameters were derived from individual structural MRI scan and HD-EEG data acquired at baseline (Day 1) to model current intensity and individual preferential theta peak. Participants were randomized to either sham or tACS (Days 2 and 3) and then completed a visual WM task and a control task. Our findings reveal that tACS was safe and well-tolerated among participants. We found a significantly increased accuracy in the visual WM but not the control task following tACS. Moreover, this enhancement in WM accuracy was greater after tACS than during tACS, indicating stronger offline effects than online effects. Our study therefore supports the application of repeated sessions of brain stimulation in 22q11.2DS.

Social skills in neurodevelopmental disorders: a study using role-plays to assess adolescents and young adults with 22q11.2 deletion syndrome and autism spectrum disorders.

BACKGROUNDS: Social skills are frequently impaired in neurodevelopmental disorders and genetic conditions, including 22q11.2 deletion syndrome (22q11DS) and autism spectrum disorders (ASD). Although often assessed with questionnaires, direct assessment provides a more valid estimate of the constructs. Role-plays (i.e., simulates situational settings) therefore appear to be an appropriate indicator of social skills in daily life. METHODS: This co-registered study involved 53 individuals with 22q11DS, 34 individuals with ASD, and 64 typically developing (TD) peers aged 12-30 years. All participants were assessed with role-plays as well as parent-reported questionnaires and clinical interviews focusing on social skills, functioning and anxiety. RESULTS: Both clinical groups showed impaired social skills compared to TD, but distinct social profiles emerged between the groups. Individuals with 22q11DS displayed higher social appropriateness and clarity of speech but weaker general argumentation and negotiation skills, with the opposite pattern observed in participants with ASD. No association was found between social skills measured by direct observation and caregiver reports. Social anxiety, although higher in clinical groups than in TD, was not associated with role-plays. CONCLUSIONS: This study highlights the need to train social skills through tailored interventions to target the specific difficulties of each clinical population. It also highlights the importance of combining measures as they do not necessarily provide the same outcome.

Cognitive emotion regulation difficulties increase affective reactivity to daily-life stress in autistic adolescents and young adults.

LAY ABSTRACT: Previous research has shown that autistic individuals report high levels of perceived stress and have an increased likelihood of developing mental health difficulties. Increase in individuals' negative emotions in relation to perceived stress (i.e. affective reactivity to stress) is a known risk factor for mental health difficulties. In this study, we investigated perceived daily stress and affective reactivity to stress in autistic (n = 39, age = 18.4) and non-autistic (n = 55, age = 18.1) adolescents and young adults. We used the ecological momentary assessment, a technique that allows to assess individuals repeatedly in their daily life using their smartphone. Moreover, participants filled a questionnaire to evaluate the strategies they use to regulate emotions when faced with difficulties. Finally, a clinical interview and a parent-report questionnaire were used to assess mental health symptoms. Autistic youth reported higher levels of perceived daily stress compared with non-autistic peers. Moreover, they showed increased affective reactivity to stress related to their daily activities. Autistic participants reported more emotion regulation difficulties (e.g. more repetitive thinking of difficulties) compared with non-autistic participants. Difficulties in emotion regulation increased negative emotions in relation to stress and might contribute to the severity of mental health symptoms. We conclude that adolescents and young adults with autism report high perceived stress in their daily lives. To minimize the negative impact of stress and the development of mental health symptoms, people supporting autistic young people could focus on stress management skills and the strategies that the youth use to manage emotions.

Chromatin regulators in the TBX1 network confer risk for conotruncal heart defects in 22q11.2DS.

Congenital heart disease (CHD) affecting the conotruncal region of the heart, occurs in 40-50% of patients with 22q11.2 deletion syndrome (22q11.2DS). This syndrome is a rare disorder with relative genetic homogeneity that can facilitate identification of genetic modifiers. Haploinsufficiency of TBX1, encoding a T-box transcription factor, is one of the main genes responsible for the etiology of the syndrome. We suggest that genetic modifiers of conotruncal defects in patients with 22q11.2DS may be in the TBX1 gene network. To identify genetic modifiers, we analyzed rare, predicted damaging variants in whole genome sequence of 456 cases with conotruncal defects and 537 controls, with 22q11.2DS. We then performed gene set approaches and identified chromatin regulatory genes as modifiers. Chromatin genes with recurrent damaging variants include EP400, KAT6A, KMT2C, KMT2D, NSD1, CHD7 and PHF21A. In total, we identified 37 chromatin regulatory genes, that may increase risk for conotruncal heart defects in 8.5% of 22q11.2DS cases. Many of these genes were identified as risk factors for sporadic CHD in the general population. These genes are co-expressed in cardiac progenitor cells with TBX1, suggesting that they may be in the same genetic network. The genes KAT6A, KMT2C, CHD7 and EZH2, have been previously shown to genetically interact with TBX1 in mouse models. Our findings indicate that disturbance of chromatin regulatory genes impact the TBX1 gene network serving as genetic modifiers of 22q11.2DS and sporadic CHD, suggesting that there are some shared mechanisms involving the TBX1 gene network in the etiology of CHD.

Multivariate patterns of disrupted sleep longitudinally predict affective vulnerability to psychosis in 22q11.2 Deletion Syndrome.

22q11.2 deletion syndrome (22q11DS) contributes dramatically to increased genetic risk for psychopathology, and in particular schizophrenia. Sleep disorders, including obstructive sleep apnea (OSA), are also highly prevalent, making 22q11DS a unique model to explore their impact on psychosis vulnerability. Still, the contribution of sleep disturbances to psychosis vulnerability remains unclear. We characterized the sleep phenotype of 69 individuals with 22q11DS and 38 healthy controls with actigraphy and sleep questionnaires. Psychiatric symptoms were measured concomitantly with the baseline sleep assessment and at longitudinal follow-up, 3.58±0.85 years later. We used a novel multivariate partial-least-square-correlation (PLSC) approach to identify sleep patterns combining objective and subjective variables, which correlated with psychiatric symptoms. We dissected longitudinal pathways linking sleep disturbances to psychosis, using multi-layer-network-analysis. 22q11DS was characterized by a non-restorative sleep pattern, combining increased daytime fatigue despite longer sleep duration. Non-restorative sleep combined with OSA symptoms correlated with both emotional and psychotic symptoms. Moreover, a sleep pattern evocative of OSA predicted longitudinal worsening of positive and negative symptoms, by accentuating the effects of emotional dysregulation. These results suggest that sleep disturbances could significantly increase psychosis risk, along an affective pathway. If confirmed, this suggests that systematic screening of sleep quality could mitigate psychosis vulnerability in 22q11DS.

Increased affective reactivity to daily social stressors is associated with more severe psychotic symptoms in youths with 22q11.2 deletion syndrome.

BACKGROUND: Increased reactivity to minor stressors is considered a risk factor for psychosis, especially in vulnerable individuals. In the present study, we investigated affective and psychotic stress reactivity as well as its link with psychotic symptoms and psychopathology in youths with 22q11.2 deletion syndrome (22q11DS), a neurogenetic condition associated with a high risk for psychosis. METHODS: A 6-day ecological momentary assessment protocol was used to assess perceived daily-life stress as well as affective and psychotic reactivity to stress in participants with 22q11DS (n = 38, age = 18.4) and healthy controls (HC; n = 53, age = 19.1). Psychotic symptoms, general psychopathology, and coping strategies were also assessed through clinical interviews and questionnaires. RESULTS: Participants with 22q11DS reported higher levels of perceived social stress (b = 0.21, p = 0.036) but lower levels of activity-related stress (b = -0.31, p = 0.003) in their daily lives compared to HC. The groups did not differ in affective or psychotic reactivity to stress, but individuals with 22q11DS who reported increased affective reactivity to social stressors showed more severe positive psychotic symptoms (rs = 0.505, p = 0.008). Finally, avoidance coping strategies moderated the association between stress and negative affects. CONCLUSIONS: Our results suggest an increased vulnerability for daily social stress in youths with 22q11DS, and link elevated social stress reactivity to heightened psychotic symptom severity. Given the high risk for psychosis in 22q11DS, interventions should focus on reducing social stress and developing adaptive coping strategies.

Updated clinical practice recommendations for managing adults with 22q11.2 deletion syndrome.

This review aimed to update the clinical practice guidelines for managing adults with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society recruited expert clinicians worldwide to revise the original clinical practice guidelines for adults in a stepwise process according to best practices: (1) a systematic literature search (1992-2021), (2) study selection and synthesis by clinical experts from 8 countries, covering 24 subspecialties, and (3) formulation of consensus recommendations based on the literature and further shaped by patient advocate survey results. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text review, with 2318 meeting inclusion criteria (clinical care relevance to 22q11.2DS) including 894 with potential relevance to adults. The evidence base remains limited. Thus multidisciplinary recommendations represent statements of current best practice for this evolving field, informed by the available literature. These recommendations provide guidance for the recognition, evaluation, surveillance, and management of the many emerging and chronic 22q11.2DS-associated multisystem morbidities relevant to adults. The recommendations also address key genetic counseling and psychosocial considerations for the increasing numbers of adults with this complex condition.

Updated clinical practice recommendations for managing children with 22q11.2 deletion syndrome.

This review aimed to update the clinical practice guidelines for managing children and adolescents with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society, the international scientific organization studying chromosome 22q11.2 differences and related conditions, recruited expert clinicians worldwide to revise the original 2011 pediatric clinical practice guidelines in a stepwise process: (1) a systematic literature search (1992-2021), (2) study selection and data extraction by clinical experts from 9 different countries, covering 24 subspecialties, and (3) creation of a draft consensus document based on the literature and expert opinion, which was further shaped by survey results from family support organizations regarding perceived needs. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text reviews, including 1545 meeting criteria for potential relevance to clinical care of children and adolescents. Informed by the available literature, recommendations were formulated. Given evidence base limitations, multidisciplinary recommendations represent consensus statements of good practice for this evolving field. These recommendations provide contemporary guidance for evaluation, surveillance, and management of the many 22q11.2DS-associated physical, cognitive, behavioral, and psychiatric morbidities while addressing important genetic counseling and psychosocial issues.

Confabulations in a teenager with a right frontal hemispherotomy: Possible underlying mechanisms.

Objective: Confabulations, i.e. false memories without intention to deceive, can be observed in adults with frontal brain damage. Confabulations are typically associated with episodic memory and/or executive disorders although the severity of these impairments is highly variable. Confabulations may also be associated with emotional/motivational particularities, as a positive bias seems to prevail in such situations. Several distinct cognitive and socio-affective processes may account for the various types of confabulations and these issues remain open. Method: We present the case of a teenager with an early acquired frontal damage, referred for "strange lies." Besides a standard neuropsychological assessment, we explored (1) source memory, using a reality-monitoring task, (2) episodic autobiographical memory, including both the recollection of the past memories and the ability to imagine future personal events, with an episodic future thinking task (EFT), (3) the sense of self, with questionnaires targeting self-representations, self-esteem and self-competence. Results: The results showed the expected source memory deficits and poor episodic future thinking, whereas episodic autobiographical memory was preserved, contrary to the episodic memory dysfunction usually evidenced in adult confabulators. The confabulations produced by this teenager displayed a clear positive bias, seemed to fit to personal/social goals and to wishful ideations, and were associated with an above average self-esteem and self-representation. Conclusions: These results support the hypothesis of self-identity and emotional regulatory roles of the confabulations. Although the literature on confabulating children/teenagers is nearly non-existent, a more systematic screening of confabulations should be conducted in order to avoid false interpretation to strange discourse or behavior.

Visual processing of complex social scenes in 22q11.2 deletion syndrome: Relevance for negative symptoms.

Current explanatory models of negative symptoms in schizophrenia have suggested the role of social cognition in symptom formation and maintenance. This study examined a core aspect of social cognition, namely social perception, and its association with clinical manifestations in 22q11.2 deletion syndrome (22q11DS), a genetic model of schizophrenia. We used an eye-tracking device to analyze developmental trajectories of complex and dynamic social scenes exploration in 58 participants with 22q11DS compared to 79 typically developing controls. Participants with 22q11DS showed divergent patterns of social scene exploration compared to healthy individuals from childhood to adulthood. We evidenced a more scattered gaze pattern and a lower number of shared gaze foci compared to healthy controls. Associations with negative symptoms, anxiety level, and face recognition were observed. Findings reveal abnormal visual exploration of complex social information from childhood to adulthood in 22q11DS. Atypical gaze patterns appear related to clinical manifestations in this syndrome.

Characterizing Daily-Life Social Interactions in Adolescents and Young Adults with Neurodevelopmental Disorders: A Comparison Between Individuals with Autism Spectrum Disorders and 22q11.2 Deletion Syndrome.

Social impairments are common features of 22q11.2 deletion syndrome (22q11DS) and autism spectrum disorders (ASD). The Ecological Momentary Assessment (EMA) allowed access to daily-life information in order to explore the phenomenology of social interactions. 32 individuals with 22q11DS, 26 individuals with ASD and 44 typically developing peers (TD) aged 12-30 were assessed during 6 days 8 times a day using a mobile app. Participants with 22q11DS and ASD did not spend more time alone but showed distinct implication in the social sphere than TD. Distinct profiles emerged between the two conditions regarding the subjective experience of aloneness and the subjective experience of social interactions. This study highlights distinct social functioning profiles in daily-life in 22q11DS and ASD that points towards different therapeutic targets.

Altered developmental trajectories of verbal learning skills in 22q11.2DS: associations with hippocampal development and psychosis.

BACKGROUND: The cognitive profile in 22q11.2 deletion syndrome (22q11.2DS) is often characterized by a discrepancy between nonverbal vs. verbal reasoning skills, in favor of the latter skills. This dissociation has also been observed in memory, with verbal learning skills described as a relative strength. Yet the development of these skills is still to be investigated. We thus aimed to explore verbal learning longitudinally. Furthermore, we explored verbal learning and its respective associations with hippocampal alterations and psychosis, which remain largely unknown despite their high prevalence in 22q11.2DS. METHODS: In total, 332 individuals (173 with 22q11.2DS) aged 5-30 years completed a verbal-paired associates task. Mixed-models regression analyses were conducted to explore developmental trajectories with threefold objectives. First, verbal learning and retention trajectories were compared between 22q11.2DS vs. HC. Second, we examined hippocampal volume development in 22q11.2DS participants with lower vs. higher verbal learning performance. Third, we explored verbal learning trajectories in 22q11.2DS participants with vs. without positive psychotic symptoms and with vs. without a psychotic spectrum disorder (PSD). RESULTS: Our findings first reveal lower verbal learning performance in 22q11.2DS, with a developmental plateau emerging from adolescence. Second, participants with lower verbal learning scores displayed a reduced left hippocampal tail volume. Third, participants with PSD showed a deterioration of verbal learning performance, independently of verbal reasoning skills. CONCLUSION: Our study challenges the current view of preserved verbal learning skills in 22q11.2DS and highlights associations with specific hippocampal alterations. We further identify verbal learning as a novel cognitive marker for psychosis in 22q11.2DS.

Effects of risperidone on psychotic symptoms and cognitive functions in 22q11.2 deletion syndrome: Results from a clinical trial.

Background: Carriers of the 22q11.2 deletion syndrome (22q11DS) have an enhanced risk of developing psychotic disorders. Full-blown psychosis is typically diagnosed by late adolescence/adulthood. However, cognitive decline is already apparent as early as childhood. Recent findings in mice show that antipsychotic medication administered during adolescence has a long-lasting neuroprotective effect. These findings offer promising evidence for implementing preventive treatment in humans at risk for psychosis. Methods: We conducted a 12-week double-blind randomized controlled clinical trial with individuals with 22q11DS. Recruitment difficulties resulted in a final sample size of 13 participants (n = 6 treated with antipsychotics and n = 7 receiving placebo). We examined the response to treatment and assessed its short- and long-term effects on psychotic symptomatology using the Structured Interview for Psychosis-Risk Syndromes (SIPS) and cognitive measures. Results: First, two treated participants discontinued treatment after experiencing adverse events. Second, treated participants showed a short-term improvement in 33.3% of the SIPS items, mainly those targeting negative symptoms. Third, reliable improvements in at least one measure of working memory and attention were respectively found in 83.3 and 66.7% of treated participants. Conclusion: This is the first double-blind study to investigate the potential neuroprotective effect of antipsychotics in humans at risk for psychosis. Our preliminary results suggest that antipsychotic treatment may prevent long-term deterioration in clinical symptoms and cognitive skills. Yet, given the limited sample size, our findings need to be replicated in larger samples. To do so, future studies may rather adopt open-label or retrospective designs to ensure sufficient power. Clinical trial registration: [www.ClinicalTrials.gov], identifier [NCT04639960].

Contribution of schizophrenia polygenic burden to longitudinal phenotypic variance in 22q11.2 deletion syndrome.

While the recurrent 22q11.2 deletion is one of the strongest genetic risk factors for schizophrenia (SCZ), variability of its associated neuropsychiatric endophenotypes reflects its incomplete penetrance for psychosis development. To assess whether this phenotypic variability is linked to common variants associated with SCZ, we studied the association between SCZ polygenic risk score (PRS) and longitudinally acquired phenotypic information of the Swiss 22q11.2DS cohort (n = 97, 50% females, mean age 17.7 yr, mean visit interval 3.8 yr). The SCZ PRS with the best predictive performance was ascertained in the Estonian Biobank (n = 201,146) with LDpred. The infinitesimal SCZ PRS model showed the strongest capacity in discriminating SCZ cases from controls with one SD difference in SCZ PRS corresponding to an odds ratio (OR) of 1.73 (95% CI 1.57-1.90, P = 1.47 × 10-29). In 22q11.2 patients, random-effects ordinal regression modelling using longitudinal data showed SCZ PRS to have the strongest effect on social anhedonia (OR = 2.09, P = 0.0002), and occupational functioning (OR = 1.82, P = 0.0003) within the negative symptoms course, and dysphoric mood (OR = 2.00, P = 0.002) and stress intolerance (OR = 1.76, P = 0.0002) within the general symptoms course. Genetic liability for SCZ was additionally associated with full scale cognitive decline (ß = -0.25, P = 0.02) and with longitudinal volumetric reduction of the right and left hippocampi (ß = -0.28, P = 0.005; ß = -0.23, P = 0.02, respectively). Our results indicate that the polygenic contribution to SCZ acts upon the threshold-lowering first hit (i.e., the deletion). It modifies the endophenotypes of 22q11.2DS and augments the derailment of developmental trajectories of negative and general symptoms, cognition, and hippocampal volume.

Exploring associations between diurnal cortisol, stress, coping and psychopathology in adolescents and young adults with 22q11.2 deletion syndrome.

Background: 22q11.2 deletion syndrome (22q11DS) is a neurogenetic condition associated to a high risk for psychiatric disorders, including psychosis. Individuals with 22q11DS are thought to experience increased levels of chronic stress, which could lead to alterations in hypothalamic-pituitary-adrenocortical (HPA)-axis functioning. In the current study, we investigated for the first time diurnal salivary cortisol profiles in adolescents and young adults with 22q11DS as well as their link with stress exposure, coping strategies and psychopathology, including psychotic symptoms. Methods: Salivary cortisol was collected from adolescents and young adults with 22q11DS (n = 30, age = 19.7) and matched healthy controls (HC; n = 36, age = 18.5) six times a day for two days. Exposure to stressful life events, including peer victimization, coping strategies and general psychopathology were assessed with questionnaires. Psychotic symptoms and psychiatric comorbidities were evaluated with clinical interviews. Results: We observed similar daily levels and diurnal profiles of salivary cortisol in adolescents and young adults with 22q11DS compared to HCs. However, participants with 22q11DS reported less frequent exposure to stress than HCs. In 22q11DS, we observed a significant association between the use of non-adaptive coping strategies and the severity of psychotics symptoms. Cortisol level was not associated to severity of psychotic symptoms, but elevated cortisol awakening response (CAR) was found in participants with 22q11DS with higher levels of general psychopathology. Conclusions: Our results do not support earlier propositions of altered HPA-axis functioning in 22q11DS but highlight the need to further investigate diurnal cortisol as an indicator of HPA-axis functioning and its link with (earlier) stress exposure and psychopathology in this population. Interventions should target the development of adaptive coping skills in preventing psychosis in 22q11DS.

General psychopathology and its social correlates in the daily lives of youth.

BACKGROUND: Adolescence is a period of both great social change, and of vulnerability to psychiatric distress. However, little is known about the associations between early psychopathology and social interactions at the fundamental level of daily life. To better understand the social correlates of subclinical psychopathology in adolescence, we assessed associations between general psychopathology and the quantity and quality of daily-life social interactions. METHODS: During a six-day experience sampling period, adolescent and young adult participants in Study 1 (n = 663) and Study 2 (n = 1027) reported the quantity and quality of their everyday social interactions. General psychopathology was assessed using the Symptom Checklist-90 and Brief Symptom Inventory-53. The relationship between psychopathology and each outcome variable was tested in separate multilevel linear and logistic regression models. RESULTS: General psychopathology was associated with social interaction quality. Associations between psychopathology and the number of social interactions were less apparent: In Study 1, participants with more psychopathology were not more alone, whereas Study 2 participants with higher levels of psychopathology were alone more. LIMITATIONS: Limitations include no separate investigation of distinct types of psychopathology, and relatively low compliance to the experience sampling in Study 2. CONCLUSIONS: Consistent associations between subclinical psychopathology and the quality of social interactions support the fundamentally social nature of early psychopathology. Moreover, negative experiences of social interactions may be more valuable markers of early psychopathology than a reduced quantity of social behaviors. Conceptualizations of daily-life social functioning, and prevention/intervention efforts would benefit from a greater consideration of the quality of everyday social experiences.

Be(com)ing social: Daily-life social interactions and parental bonding.

Parents are known to provide a lasting basis for their children's social development. Understanding parent-driven socialization is particularly relevant in adolescence, as an increasing social independence is developed. However, the relationship between key parenting styles of care and control and the microlevel expression of daily-life social interactions has been insufficiently studied. Adolescent and young adult twins and their nontwin siblings (N = 635; mean age = 16.6; age range = 14.2-21.9; 58.6% female; 79.5% in or having completed higher secondary/tertiary education; 2.8% speaking language other than Dutch at home) completed the Parental Bonding Instrument (PBI) on parental care and control. Participants also completed a 6-day experience sampling period (10 daily beeps, mean compliance = 68.0%) to assess daily-life social interactions. Higher overall parental bonding quality (of both parents) related to more positive social experiences in daily life (e.g., belonging in company), but not to more social behaviors (e.g., being with others). Factor analysis indicated a three-factor structure of the PBI, with care, denial of psychological autonomy, and encouragement of behavioral freedom. Paternal care was uniquely predictive of better social experiences. These findings demonstrate how parenting styles may be uniquely associated with how adolescents experience their social world, with a potentially important role for fathers in particular. This complements the long-held idea of socialization through parenting by bringing it into the context of daily life and implies how both conceptualizations of social functioning and interventions aimed at alleviating social dysfunction might benefit from a stronger consideration of day-to-day social experiences. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Aberrant Developmental Patterns of Gamma-Band Response and Long-Range Communication Disruption in Youths With 22q11.2 Deletion Syndrome.

OBJECTIVE: Brain oscillations play a pivotal role in synchronizing responses of local and global ensembles of neurons. Patients with schizophrenia exhibit impairments in oscillatory response, which are thought to stem from abnormal maturation during critical developmental stages. Studying individuals at genetic risk for psychosis, such as 22q11.2 deletion carriers, from childhood to adulthood may provide insights into developmental abnormalities. METHODS: The authors acquired 106 consecutive T1-weighted MR images and 40-Hz auditory steady-state responses (ASSRs) with high-density (256 channel) EEG in a group of 58 22q11.2 deletion carriers and 48 healthy control subjects. ASSRs were analyzed with 1) time-frequency analysis using Morlet wavelet decomposition, 2) intertrial phase coherence (ITPC), and 3) theta-gamma phase-amplitude coupling estimated in the source space between brain regions activated by the ASSRs. Additionally, volumetric analyses were performed with FreeSurfer. Subanalyses were conducted in deletion carriers who endorsed psychotic symptoms and in subgroups with different age bins. RESULTS: Deletion carriers had decreased theta and late-latency 40-Hz ASSRs and phase synchronization compared with control subjects. Deletion carriers with psychotic symptoms displayed a further reduction of gamma-band response, decreased ITPC, and decreased top-down modulation of gamma-band response in the auditory cortex. Reduced gamma-band response was correlated with the atrophy of auditory cortex in individuals with psychotic symptoms. In addition, a linear increase of theta and gamma power from childhood to adulthood was found in control subjects but not in deletion carriers. CONCLUSIONS: The results suggest that while all deletion carriers exhibit decreased gamma-band response, more severe local and long-range communication abnormalities are associated with the emergence of psychotic symptoms and gray matter loss. Additionally, the lack of age-related changes in deletion carriers indexes a potential developmental impairment in circuits underlying the maturation of neural oscillations during adolescence. The progressive disruption of gamma-band response in 22q11.2 deletion syndrome supports a developmental perspective toward understanding and treating psychotic disorders.

Agency Deficits in a Human Genetic Model of Schizophrenia: Insights From 22q11DS Patients.

Schizophrenia is a chronic and disabling mental illness characterized by a disordered sense of self. Current theories suggest that deficiencies in the sense of control over one's actions (Sense of Agency, SoA) may underlie some of the symptoms of schizophrenia. However, it is not clear if agency deficits are a precursor or a result of psychosis. Here, we investigated full body agency using virtual reality in a cohort of 22q11 deletion syndrome participants with a genetic propensity for schizophrenia. In two experiments employing virtual reality, full body motion tracking, and online feedback, we investigated SoA in two separate domains. Our results show that participants with 22q11DS had a considerable deficit in monitoring their actions, compared to age-matched controls in both the temporal and spatial domain. This was coupled with a bias toward erroneous attribution of actions to the self. These results indicate that nonpsychotic 22q11DS participants have a domain general deficit in the conscious sensorimotor mechanisms underlying the bodily self. Our data reveal an abnormality in the SoA in a cohort with a genetic predisposition for schizophrenia, but without psychosis, providing evidence that deficits in delineation of the self may be a precursor rather than a result of the psychotic state.

A normative chart for cognitive development in a genetically selected population.

Certain pathogenic genetic variants impact neurodevelopment and cause deviations from typical cognitive trajectories. Understanding variant-specific cognitive trajectories is clinically important for informed monitoring and identifying patients at risk for comorbid conditions. Here, we demonstrate a variant-specific normative chart for cognitive development for individuals with 22q11.2 deletion syndrome (22q11DS). We used IQ data from 1365 individuals with 22q11DS to construct variant-specific normative charts for cognitive development (Full Scale, Verbal, and Performance IQ). This allowed us to calculate Z-scores for each IQ datapoint. Then, we calculated the change between first and last available IQ assessments (delta Z-IQ-scores) for each individual with longitudinal IQ data (n = 708). We subsequently investigated whether using the variant-specific IQ-Z-scores would decrease required sample size to detect an effect with schizophrenia risk, as compared to standard IQ-scores. The mean Z-IQ-scores for FSIQ, VIQ, and PIQ were close to 0, indicating that participants had IQ-scores as predicted by the normative chart. The mean delta-Z-IQ-scores were equally close to 0, demonstrating a good fit of the normative chart and indicating that, as a group, individuals with 22q11DS show a decline in IQ-scores as they grow into adulthood. Using variant-specific IQ-Z-scores resulted in 30% decrease of required sample size, as compared to the standard IQ-based approach, to detect the association between IQ-decline and schizophrenia (p < 0.01). Our findings suggest that using variant-specific normative IQ data significantly reduces required sample size in a research context, and may facilitate a more clinically informative interpretation of IQ data. This approach allows identification of individuals that deviate from their expected, variant-specific, trajectory. This group may be at increased risk for comorbid conditions, such as schizophrenia in the case of 22q11DS.