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Although sensitizing processes occur earlier, schizophrenia is diagnosed in young adulthood, which suggests that it might involve a pathological transition during late brain development in predisposed individuals. Parvalbumin (PV) interneuron alterations have been noticed, but their role in the disease is unclear. Here we demonstrate that adult LgDel+/- mice, a genetic model of schizophrenia, exhibit PV neuron hypo-recruitment and associated chronic PV neuron plasticity together with network and cognitive deficits. All these deficits can be permanently rescued by chemogenetic activation of PV neurons or D2R antagonist treatments, specifically in the ventral hippocampus (vH) or medial-prefrontal cortex during a late-adolescence-sensitive time window. PV neuron alterations were initially restricted to the hippocampal CA1/subiculum, where they became responsive to treatment in late adolescence. Therefore, progression to disease in schizophrenia-model mice can be prevented by treatments supporting vH-mPFC PV network function during a sensitive time window late in adolescence, suggesting therapeutic strategies to prevent the outbreak of schizophrenia.
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Disfunción Cognitiva/terapia , Antagonistas de los Receptores de Dopamina D2/farmacología , Hipocampo/efectos de los fármacos , Interneuronas/efectos de los fármacos , Plasticidad Neuronal/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Esquizofrenia/terapia , Adolescente , Animales , Modelos Animales de Enfermedad , Hipocampo/patología , Humanos , Ratones , Ratones Endogámicos C57BL , Parvalbúminas/metabolismo , Corteza Prefrontal/patologíaRESUMEN
The temporal variability of the thalamus in functional networks may provide valuable insights into the pathophysiology of schizophrenia. To address the complexity of the role of the thalamic nuclei in psychosis, we introduced micro-co-activation patterns (µCAPs) and employed this method on the human genetic model of schizophrenia 22q11.2 deletion syndrome (22q11.2DS). Participants underwent resting-state functional MRI and a data-driven iterative process resulting in the identification of six whole-brain µCAPs with specific activity patterns within the thalamus. Unlike conventional methods, µCAPs extract dynamic spatial patterns that reveal partially overlapping and non-mutually exclusive functional subparts. Thus, the µCAPs method detects finer foci of activity within the initial seed region, retaining valuable and clinically relevant temporal and spatial information. We found that a µCAP showing co-activation of the mediodorsal thalamus with brain-wide cortical regions was expressed significantly less frequently in patients with 22q11.2DS, and its occurrence negatively correlated with the severity of positive psychotic symptoms. Additionally, activity within the auditory-visual cortex and their respective geniculate nuclei was expressed in two different µCAPs. One of these auditory-visual µCAPs co-activated with salience areas, while the other co-activated with the default mode network (DMN). A significant shift of occurrence from the salience+visuo-auditory-thalamus to the DMN + visuo-auditory-thalamus µCAP was observed in patients with 22q11.2DS. Thus, our findings support existing research on the gatekeeping role of the thalamus for sensory information in the pathophysiology of psychosis and revisit the evidence of geniculate nuclei hyperconnectivity with the audio-visual cortex in 22q11.2DS in the context of dynamic functional connectivity, seen here as the specific hyper-occurrence of these circuits with the task-negative brain networks.
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Síndrome de DiGeorge , Trastornos Psicóticos , Esquizofrenia , Humanos , Imagen por Resonancia Magnética , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Tálamo/diagnóstico por imagenRESUMEN
OBJECTIVES: This retrospective study aims to investigate the evolution and clinical course of psychotic disorders from three large international cohorts of individuals with 22q11.2 deletion syndrome (22q11.2DS) (Tel Aviv, Philadelphia, and Geneva). METHODS: We followed 118 individuals with 22q11.2DS from several years before the onset to several years after the onset of psychotic disorders. Data from structured baseline assessment of psychiatric disorders, symptoms of prodrome, indicators and types of psychotic disorders were collected. Additionally, cognitive evaluation was conducted using the age-appropriate Wechsler Intelligence Scale. Electronic medical records were reviewed for medication usage, occupational status, living situation, and psychiatric hospitalizations. RESULTS: At baseline evaluation, the most common psychiatric disorders were anxiety disorder (80%) and attention/deficit hyperactivity disorder (50%). The age of onset of prodromal symptoms and conversion to psychotic disorders were 18.6 ± 6.8 and 20.3 ± 7.2, respectively. The most common prodromal symptoms were exacerbation of anxiety symptoms and social isolation. Of the psychotic disorders, schizophrenia was the most common, occurring in 49% of cases. History of at least one psychiatric hospitalization was present in 43% of participants, and the number of psychiatric hospitalizations was 2.1 ± 1.4. Compared to the normalized chart, IQ scores in our cohort were lower after vs. before conversion to psychosis. Following conversion there was a decrease in the use of stimulants and antidepressants and an increase in antipsychotics use, and most individuals with 22q11.2DS were unemployed and lived with their parents. CONCLUSIONS: Our results indicate that 22q11.2DS psychosis is like non-22q11.2DS in its course, symptoms, and cognitive and functional impairments.
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Brain oscillations are produced by the coordinated activity of large groups of neurons and different rhythms are thought to reflect different modes of information processing. These modes, in turn, are known to occur at different spatial scales. Nevertheless, how these rhythms support different spatial modes of information processing at the brain scale is not yet fully understood. Here we use "Joint Time-Vertex Spectral Analysis" to characterize the joint spectral content of brain activity both in time (temporal frequencies) and in space over the connectivity graph (spatial connectome harmonics). This method allows us to characterize the relationship between spatially localized or distributed neural processes on one side and their respective temporal frequency bands in source-reconstructed M/EEG signals. We explore this approach on two different datasets, an auditory steady-state response (ASSR) and a visual grating task. Our results suggest that different information processing mechanisms are carried out at different frequency bands: while spatially distributed activity (which may also be interpreted as integration) specifically occurs at low temporal frequencies (alpha and theta) and low graph spatial frequencies, localized electrical activity (i.e., segregation) is observed at high temporal frequencies (high and low gamma) over restricted high spatial graph frequencies. Crucially, the estimated contribution of the distributed and localized neural activity predicts performance in a behavioral task, demonstrating the neurophysiological relevance of the joint time-vertex spectral representation.
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Conectoma , Humanos , Cabeza , Cognición , Neuronas , EncéfaloRESUMEN
The 22q11.2 deletion syndrome (22q11.2DS) results from non-allelic homologous recombination between low-copy repeats termed LCR22. About 60%-70% of individuals with the typical 3 megabase (Mb) deletion from LCR22A-D have congenital heart disease, mostly of the conotruncal type (CTD), whereas others have normal cardiac anatomy. In this study, we tested whether variants in the hemizygous LCR22A-D region are associated with risk for CTDs on the basis of the sequence of the 22q11.2 region from 1,053 22q11.2DS individuals. We found a significant association (FDR p < 0.05) of the CTD subset with 62 common variants in a single linkage disequilibrium (LD) block in a 350 kb interval harboring CRKL. A total of 45 of the 62 variants were associated with increased risk for CTDs (odds ratio [OR) ranges: 1.64-4.75). Associations of four variants were replicated in a meta-analysis of three genome-wide association studies of CTDs in affected individuals without 22q11.2DS. One of the replicated variants, rs178252, is located in an open chromatin region and resides in the double-elite enhancer, GH22J020947, that is predicted to regulate CRKL (CRK-like proto-oncogene, cytoplasmic adaptor) expression. Approximately 23% of patients with nested LCR22C-D deletions have CTDs, and inactivation of Crkl in mice causes CTDs, thus implicating this gene as a modifier. Rs178252 and rs6004160 are expression quantitative trait loci (eQTLs) of CRKL. Furthermore, set-based tests identified an enhancer that is predicted to target CRKL and is significantly associated with CTD risk (GH22J020946, sequence kernal association test (SKAT) p = 7.21 × 10-5) in the 22q11.2DS cohort. These findings suggest that variance in CTD penetrance in the 22q11.2DS population can be explained in part by variants affecting CRKL expression.
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Deleción Cromosómica , Cromosomas Humanos Par 22/genética , Cardiopatías Congénitas/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Estudio de Asociación del Genoma Completo , Cardiopatías Congénitas/patología , Humanos , Desequilibrio de Ligamiento , Masculino , Fenotipo , Proto-Oncogenes Mas , Duplicaciones Segmentarias en el GenomaRESUMEN
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.
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Síndrome de DiGeorge , Adolescente , Humanos , Niño , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/terapia , Asesoramiento Genético , Encuestas y CuestionariosRESUMEN
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.
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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.
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Síndrome de DiGeorge , Trastornos Psicóticos , Adolescente , Humanos , Síndrome de DiGeorge/complicaciones , Trastornos Psicóticos/epidemiología , Aprendizaje , Aprendizaje Verbal , Hipocampo/diagnóstico por imagenRESUMEN
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.
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Disfunción Cognitiva , Síndrome de DiGeorge , Trastornos Psicóticos , Esquizofrenia , Femenino , Humanos , Adolescente , Masculino , Esquizofrenia/genética , Síndrome de DiGeorge/genética , Herencia Multifactorial/genética , Trastornos Psicóticos/genética , Disfunción Cognitiva/genéticaRESUMEN
BACKGROUND: Attention deficit and/or hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder in children with 22q11.2 deletion syndrome (22q11DS) and frequently persists into adulthood. Although medication with stimulant has been demonstrated to be highly effective in idiopathic ADHD, evidence in 22q11DS is still scarce. Previous studies have shown safety and effectiveness of methylphenidate (MPH) on core symptoms of ADHD as well as improvement of associated cognitive deficits. However, only a limited number of cognitive domains have been explored. METHODS: Twenty-three participants with 22q11DS and attention difficulties, aged 8-24 years, entered a clinical trial aiming to specify the effects of MPH on clinical symptoms, cognition, and daily-life behavior. The effects of treatment were compared with/without medication in a within-subject design. The trial included both participants naïve to the molecule and chronic users. RESULTS: Benefit from the treatment was demonstrated through a decrease in core ADHD symptoms, specifically inattention symptoms, and improvement of cognitive measures of attention and inhibition. Conversely, no significant change was found for other executive functions (such as cognitive flexibility, working memory, initiation), learning, or memory. Moreover, no significant improvement on ecological measures of daily-life executive functioning was found, possibly because of the short treatment period. We replicated safety, and although very frequent, side effects were of mild intensity and comparable with previous findings. CONCLUSIONS: This study extends the current knowledge on the effects of MPH in patients with 22q11DS. Treatment was found to be effective for core ADHD symptoms and cognitive measures of attention and inhibition.
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Trastorno por Déficit de Atención con Hiperactividad , Estimulantes del Sistema Nervioso Central , Síndrome de DiGeorge , Metilfenidato , Adulto , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/psicología , Estimulantes del Sistema Nervioso Central/efectos adversos , Niño , Síndrome de DiGeorge/inducido químicamente , Síndrome de DiGeorge/tratamiento farmacológico , Función Ejecutiva , Humanos , Metilfenidato/efectos adversos , Resultado del TratamientoRESUMEN
Schizophrenia has been extensively associated with reduced cortical thickness (CT), and its neurodevelopmental origin is increasingly acknowledged. However, the exact timing and extent of alterations occurring in preclinical phases remain unclear. With a high prevalence of psychosis, 22q11.2 deletion syndrome (22q11DS) is a neurogenetic disorder that represents a unique opportunity to examine brain maturation in high-risk individuals. In this study, we quantified trajectories of CT maturation in 22q11DS and examined the association of CT development with the emergence of psychotic symptoms. Longitudinal structural MRI data with 1-6 time points were collected from 324 participants aged 5-35 years (N = 148 22q11DS, N = 176 controls), resulting in a total of 636 scans (N = 334 22q11DS, N = 302 controls). Mixed model regression analyses were used to compare CT trajectories between participants with 22q11DS and controls. Further, CT trajectories were compared between participants with 22q11DS who developed (N = 61, 146 scans), or remained exempt of (N = 47; 98 scans) positive psychotic symptoms during development. Compared to controls, participants with 22q11DS showed widespread increased CT, focal reductions in the posterior cingulate gyrus and superior temporal gyrus (STG), and accelerated cortical thinning during adolescence, mainly in frontotemporal regions. Within 22q11DS, individuals who developed psychotic symptoms showed exacerbated cortical thinning in the right STG. Together, these findings suggest that genetic predisposition for psychosis is associated with increased CT starting from childhood and altered maturational trajectories of CT during adolescence, affecting predominantly frontotemporal regions. In addition, accelerated thinning in the STG may represent an early biomarker associated with the emergence of psychotic symptoms.
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Síndrome de Deleción 22q11 , Síndrome de DiGeorge , Trastornos Psicóticos , Esquizofrenia , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Niño , Preescolar , Síndrome de DiGeorge/diagnóstico por imagen , Síndrome de DiGeorge/genética , Humanos , Imagen por Resonancia Magnética , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/genética , Esquizofrenia/complicaciones , Esquizofrenia/genética , Adulto JovenRESUMEN
The aim of this study was to assess the impact of the COVID-19 pandemic on mental well-being of clinically referred children and adolescents and on their families from the perspective of mental health care professionals in Switzerland during the first year of the pandemic. Psychiatrists and psychologists for children and adolescents participated in an anonymous survey conducted online in April/May 2021. The survey was completed by 454 mental health care professionals, most of them working in outpatient clinics for child and adolescent psychiatry or in independent practices. Most participants indicated an important increase of referrals for depression (86.8% of respondents), anxiety disorders (81.5%), crisis interventions (76.2%), psychosomatic disorders (66.1%), suicidality (63.8%), and behavioral addictions, e.g., excessive gaming (64.6%). In contrast, referrals or treatment demands for disorders such as autism spectrum disorder or psychosis showed no substantial change or a slight decrease, respectively. According to 69% of respondents, patients experienced the highest psychological burden in January/February/March 2021. Family problems very frequently reported by mental health professionals were parents' worries about loneliness/isolation of the child (49%), child's education and academic future (33%), increased media use due to missing options of recreational activities (37.6%), as well as multiple stresses of mothers (36.3%). To conclude, the pandemic has substantially changed the pattern of disorders and the number of clinical referrals of children and adolescents with mental health problems, which has serious consequences for the treatment supply in Switzerland.
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Trastorno del Espectro Autista , COVID-19 , Adolescente , Niño , Personal de Salud , Humanos , Salud Mental , Pandemias , Derivación y Consulta , Encuestas y Cuestionarios , Suiza/epidemiologíaRESUMEN
OBJECTIVE: Executive functions (EF) and focal attention have been identified as a weakness in the profile of 22q11.2 deletion syndrome (22q11DS). However, due to a high variety of tasks used across previous studies, it remains unclear whether impairments may be more pronounced for specific subdomains of EF and focal attention. Furthermore, age-related changes have only been examined in a few studies, so far only yielding a partial view of the overall developmental profile. METHOD: In a broad age range (8-35 years) composed of longitudinal data, 183 participants (103 diagnosed with 22q11DS) completed an extensive assessment of EF and attention. To get a more comprehensive overview of specific versus global impairments, several tasks were assessed within multiple domains. RESULTS: Results suggest differential impairments and trajectories in specific EF subdomains. Specifically, our findings suggest that individuals with 22q11DS not only showed lower overall inhibition skills, but also that initiation skills developed at a slower pace compared to healthy controls. Results are less clear regarding cognitive flexibility, updating and focal attention, for which performance strongly depended on the tasks that was selected to assess the domain. CONCLUSIONS: Findings confirm and extend knowledge on differential developmental patterns of EF and attention domains in 22q11DS. They further stress the necessity to administer extensive, multifaceted evaluations to gain a more reliable overview of patients' cognitive profile.
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Síndrome de DiGeorge , Función Ejecutiva , Adolescente , Adulto , Atención/fisiología , Niño , Cognición , Síndrome de DiGeorge/complicaciones , Función Ejecutiva/fisiología , Humanos , Adulto JovenRESUMEN
This study aimed to retrospectively evaluate an association between stimulant treatment for attention-deficit/hyperactivity disorder (ADHD) in individuals with 22q11.2DS and the development of psychotic disorders, to evaluate long-term effectiveness and safety of stimulant treatment in individuals with 22q11.2DS compared to individuals with idiopathic ADHD, and to explore effects of catechol-O-methyltransferase (COMT) genotype on 22q11.2DS response to stimulants and risk of side effects. Rates of stimulant use and methylphenidate equivalent exposure were compared among individuals with 22q11.2DS, between 51 with psychotic disorders and a control group of 57 22q11.2DS without psychotic disorders, from Tel Aviv and Geneva. In addition, 44 individuals with 22q11.2DS and ADHD from Tel Aviv who initiated stimulants before age 18 years were compared to a control group of 35 age- and sex-matched controls with idiopathic ADHD, for treatment effectiveness (Clinical Global Impression Scale-Improvement), and rates of side effects. Stimulant use history and methylphenidate equivalent exposure did not differ among individuals with 22q11.2DS, between those with and without psychotic disorders. The long-term retrospective follow-up (5.3 ± 4.1 years) of stimulant-treated individuals with 22q11.2DS showed a higher rate of significant clinical improvement of ADHD symptoms, compared to idiopathic ADHD individuals (p = 0.013), and similar side effect rates. There was no effect of the COMT genotype on response to stimulants or on any side effects. This preliminary long-term retrospective analysis suggests that stimulant treatment in 22q11.2DS is apparently safe in terms of psychosis conversion and rates of side effects, and that it is effective in alleviating ADHD symptoms.
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Estimulantes del Sistema Nervioso Central , Síndrome de DiGeorge , Metilfenidato , Trastornos Psicóticos , Adolescente , Catecol O-Metiltransferasa/genética , Estimulantes del Sistema Nervioso Central/efectos adversos , Síndrome de DiGeorge/complicaciones , Síndrome de DiGeorge/tratamiento farmacológico , Síndrome de DiGeorge/genética , Humanos , Metilfenidato/efectos adversos , Trastornos Psicóticos/tratamiento farmacológico , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
How the brain's white-matter anatomy constrains brain activity is an open question that might give insights into the mechanisms that underlie mental disorders such as schizophrenia. Chromosome 22q11.2 deletion syndrome (22q11DS) is a neurodevelopmental disorder with an extremely high risk for psychosis providing a test case to study developmental aspects of schizophrenia. In this study, we used principles from network control theory to probe the implications of aberrant structural connectivity for the brain's functional dynamics in 22q11DS. We retrieved brain states from resting-state functional magnetic resonance images of 78 patients with 22q11DS and 85 healthy controls. Then, we compared them in terms of persistence control energy; that is, the control energy that would be required to persist in each of these states based on individual structural connectivity and a dynamic model. Persistence control energy was altered in a broad pattern of brain states including both energetically more demanding and less demanding brain states in 22q11DS. Further, we found a negative relationship between persistence control energy and resting-state activation time, which suggests that the brain reduces energy by spending less time in energetically demanding brain states. In patients with 22q11DS, this behavior was less pronounced, suggesting a deficiency in the ability to reduce energy through brain activation. In summary, our results provide initial insights into the functional implications of altered structural connectivity in 22q11DS, which might improve our understanding of the mechanisms underlying the disease.
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Conectoma , Síndrome de DiGeorge , Imagen por Resonancia Magnética , Trastornos Psicóticos , Sustancia Blanca/patología , Adolescente , Adulto , Niño , Síndrome de DiGeorge/diagnóstico por imagen , Síndrome de DiGeorge/patología , Síndrome de DiGeorge/fisiopatología , Susceptibilidad a Enfermedades , Femenino , Humanos , Masculino , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/patología , Trastornos Psicóticos/fisiopatología , Sustancia Blanca/diagnóstico por imagen , Adulto JovenRESUMEN
Low hippocampal volume is a consistent finding in schizophrenia and across the psychosis spectrum. However, there is a lack of studies investigating longitudinal hippocampal development and its relationship with psychotic symptoms. The 22q11.2 deletion syndrome (22q11DS) has proven to be a remarkable model for the prospective study of individuals at high risk of schizophrenia to unravel the pathophysiological processes predating the onset of psychosis. Repeated cerebral MRIs were acquired from 140 patients with 22q11DS (53 experiencing moderate-to-severe psychotic symptoms) and 135 healthy controls aged from 6 to 35 years and with up to 5 time points per participant. Hippocampal subfield analysis was conducted using FreeSurfer-v.6 and FIRST-FSL. Then, whole hippocampal and subfield volumes were compared across the groups. Relative to controls, patients with 22q11DS showed a remarkably lower volume of all subfields except for CA2/3. No divergent trajectories in hippocampal development were found. When comparing patients with 22q11DS exhibiting psychotic symptoms to those without psychosis, we detected a volume decrease during late adolescence, starting in CA1 and spreading to other subfields. Our findings suggested that hippocampal volume is consistently smaller in patients with 22q11DS. Moreover, we have demonstrated that patients with 22q11DS and psychotic symptoms undergo a further decrease in volume during adolescence, a vulnerable period for the emergence of psychosis. Interestingly, CA2/3, despite being affected in patients with psychotic symptoms, was the only area not reduced in patients with 22q11DS relative to controls, thus suggesting that its atrophy exclusively correlates with the presence of positive psychotic symptoms.
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Síndrome de DiGeorge/patología , Hipocampo/patología , Trastornos Psicóticos/patología , Adolescente , Adulto , Niño , Cromosomas Humanos Par 22 , Síndrome de DiGeorge/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia , Adulto JovenRESUMEN
Recurrent, de novo, meiotic non-allelic homologous recombination events between low copy repeats, termed LCR22s, leads to the 22q11.2 deletion syndrome (22q11.2DS; velo-cardio-facial syndrome/DiGeorge syndrome). Although most 22q11.2DS patients have a similar sized 3 million base pair (Mb), LCR22A-D deletion, some have nested LCR22A-B or LCR22A-C deletions. Our goal is to identify additional recurrent 22q11.2 deletions associated with 22q11.2DS, serving as recombination hotspots for meiotic chromosomal rearrangements. Here, using data from Affymetrix 6.0 microarrays on 1680 22q11.2DS subjects, we identified what appeared to be a nested proximal 22q11.2 deletion in 38 (2.3%) of them. Using molecular and haplotype analyses from 14 subjects and their parent(s) with available DNA, we found essentially three types of scenarios to explain this observation. In eight subjects, the proximal breakpoints occurred in a small sized 12 kb LCR distal to LCR22A, referred to LCR22A+, resulting in LCR22A+-B or LCR22A+-D deletions. Six of these eight subjects had a nested 22q11.2 deletion that occurred during meiosis in a parent carrying a benign 0.2 Mb duplication of the LCR22A-LCR22A+ region with a breakpoint in LCR22A+. Another six had a typical de novo LCR22A-D deletion on one allele and inherited the LCR22A-A+ duplication from the other parent thus appearing on microarrays to have a nested deletion. LCR22A+ maps to an evolutionary breakpoint between mice and humans and appears to serve as a local hotspot for chromosome rearrangements on 22q11.2.
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Alelos , Mapeo Cromosómico , Síndrome de DiGeorge/genética , Meiosis , Deleción Cromosómica , Cromosomas Humanos Par 22/genética , Femenino , Humanos , MasculinoRESUMEN
Introduction: Disruptions in self-monitoring processes represent key cognitive factors associated with schizophrenia spectrum disorders. In the current study, we assessed the effects of age and cognitive effort on self-monitoring for speech in adolescence, as well as its associations with personality dimensions pertaining to schizotypy and impulsivity.Methods: 121 community adolescents undertook a self-monitoring task that assesses the capacity to discriminate between self-generated overt and silent speech, for items requiring different levels of cognitive effort. Self-report measures were used to assess trait dimensions of schizotypy and impulsivity.Results: Cognitive effort, but not age, contributed to the overall rate of self-monitoring errors. Contrary to clinical psychosis and high risk samples, increased cognitive effort in healthy adolescents led to more internalising than externalising self-monitoring errors. Higher scores on the interpersonal dimension of schizotypy were associated with increases in the total rate of self-monitoring errors. No associations were found between positive schizotypy and externalising self-monitoring misattributions. Finally, trait impulsivity dimensions were not associated with self-monitoring performance.Conclusions: The present findings suggest that self-monitoring confusions may be linked to trait-risk for psychosis in adolescence. Future studies can prospectively assess whether the association between negative schizotypal traits and self-monitoring represents a distal marker of psychosis vulnerability.
Asunto(s)
Cognición/fisiología , Conducta Impulsiva/fisiología , Trastorno de la Personalidad Esquizotípica/psicología , Autoinforme , Habla/fisiología , Adolescente , Factores de Edad , Niño , Femenino , Humanos , Masculino , Desempeño Psicomotor/fisiología , Lectura , Trastorno de la Personalidad Esquizotípica/diagnóstico , Trastorno de la Personalidad Esquizotípica/fisiopatologíaRESUMEN
Reflective functioning (RF) refers to the understanding of one's own and others' behaviors in terms of mental states, whereas empathy entails the abilities to understand (cognitive empathy) and to share (affective empathy) the emotions of others. Low RF and low empathy have been previously related to externalizing behaviors, such as aggression and rule breaking. However, few longitudinal studies have simultaneously examined the relationships between these variables during adolescence. The aim of the present study is to investigate the longitudinal effects of both RF and empathy on potential changes in externalizing behaviors over time, in a group of 103 adolescents and young adults from the general population assessed repeatedly up to four times. We conducted multilevel analysis in order to examine the effects of RF and empathy on the initial levels and the trajectories of externalizing behaviors over time, while accounting for other variables previously associated with externalizing behaviors, such as age, gender, internalizing problems, and cognitive abilities. The results suggest that the ability to reflect on behaviors in terms of mental states predicted a sharper decrease in externalizing behaviors over time. Moreover, externalizing behaviors at the first assessment were associated with RF impairments and low affective empathy. Age, gender, cognitive abilities, and cognitive empathy were not associated with externalizing behaviors. We discuss how our results, based on a typically developing population, might inform primary or indicated prevention strategies for externalizing behaviors by focusing on socio-cognitive processes such as RF and affective empathy.
Asunto(s)
Agresión/psicología , Emociones/fisiología , Empatía/fisiología , Teoría de la Mente/fisiología , Adolescente , Conducta del Adolescente/psicología , Niño , Cognición/fisiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , Adulto JovenRESUMEN
22q11.2 deletion syndrome (22q11.2DS) is the most common known microdeletion in humans occurring in 1 out of 2000-4000 live births, with increasing numbers of individuals with the microdeletion living into adulthood. The aim of the study was to explore the education and employment trajectories of individuals with 22q11.2DS from childhood to adulthood in a large cohort composed of two significant samples. 260 individuals with 22q11.2DS, 134 male and 126 female, aged 5-59 years (mean age 21.3 ± 10.8 years) were evaluated at two sites, Geneva (GVA) and Tel Aviv (TA). Psychiatric comorbidities, IQ score, and adaptive functioning were assessed using gold-standard diagnostic tools. Demographic factors, such as data about education, employment, marital status, and living status, were collected. Children entering elementary school (5-12 years) were significantly more likely to attend a mainstream school, while adolescents were significantly more likely to attend special education schools (p < 0.005). Cognitive abilities, and not adaptive functioning, predicted school placement. Among adults with 22q11.2DS (n = 138), 57 (41.3%) were unemployed, 46 (33.3%) were employed in open market employment, and 35 (25.4%) worked in assisted employment. In adulthood, adaptive functioning more than cognitive abilities predicted employment. Surprisingly, psychotic spectrum disorders were not found to be associated with employment. Individuals with 22q11.2DS are characterized by heterogeneity in educational and employment profiles. We found that cognitive abilities and adaptive functioning, and not the presence of psychiatric disorders, are key factors in school placement and employment. These factors should, therefore, be taken into account when planning optimal development of individuals with 22q11.2DS.