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1.
Psychol Med ; 53(8): 3644-3651, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35144716

RESUMEN

BACKGROUND: While comorbidity of clinical high-risk for psychosis (CHR-P) status and social anxiety is well-established, it remains unclear how social anxiety and positive symptoms covary over time in this population. The present study aimed to determine whether there are more than one covariant trajectory of social anxiety and positive symptoms in the North American Prodrome Longitudinal Study cohort (NAPLS 2) and, if so, to test whether the different trajectory subgroups differ in terms of genetic and environmental risk factors for psychotic disorders and general functional outcome. METHODS: In total, 764 CHR individuals were evaluated at baseline for social anxiety and psychosis risk symptom severity and followed up every 6 months for 2 years. Application of group-based multi-trajectory modeling discerned three subgroups based on the covariant trajectories of social anxiety and positive symptoms over 2 years. RESULTS: One of the subgroups showed sustained social anxiety over time despite moderate recovery in positive symptoms, while the other two showed recovery of social anxiety below clinically significant thresholds, along with modest to moderate recovery in positive symptom severity. The trajectory group with sustained social anxiety had poorer long-term global functional outcomes than the other trajectory groups. In addition, compared with the other two trajectory groups, membership in the group with sustained social anxiety was predicted by higher levels of polygenic risk for schizophrenia and environmental stress exposures. CONCLUSIONS: Together, these analyses indicate differential relevance of sustained v. remitting social anxiety symptoms in the CHR-P population, which in turn may carry implications for differential intervention strategies.


Asunto(s)
Trastornos Psicóticos , Esquizofrenia , Humanos , Estudios Longitudinales , Factores de Riesgo , Síntomas Prodrómicos , Ansiedad/epidemiología
2.
Soc Psychiatry Psychiatr Epidemiol ; 58(4): 559-568, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36348056

RESUMEN

PURPOSE: Migrant status is a known risk factor for psychosis, but the underlying causes of this vulnerability are poorly understood. Recently, studies have begun to explore whether migrant status predicts transition to psychosis in individuals at clinical high risk (CHR) for psychosis. Results, however, have been inconclusive. The present study assessed the impact of migrant status on clinical symptoms and functional outcome in individuals at CHR for psychosis who took part in the NAPLS-3 study. METHODS: Participants' migrant status was classified as native-born, first-generation, or second-generation migrant. Clinical symptoms were assessed using the Structured Interview for Psychosis-Risk Syndromes (SIPS); functional outcome was measured using the Global Functioning Scales:Social and Role (GF:S; GF:R). Assessments were conducted at baseline, 12-months, 18-months, and 24-months follow-up. Generalized linear mixed models for repeated measures were used to examine changes over time and differences between groups. RESULTS: The overall sample included 710 individuals at CHR for psychosis (54.2% males; Age: M = 18.19; SD = 4.04). A mixed model analysis was conducted, and no significant differences between groups in symptoms or functioning were observed at any time point. Over time, significant improvement in symptoms and functioning was observed within each group. Transition rates did not differ across groups. CONCLUSION: We discuss potential factors that might explain the lack of group differences. Overall, migrants are a heterogeneous population. Discerning the impact of migration from that of neighborhood ethnic density, social disadvantage or socio-economic status of different ethnic groups could help better understand vulnerability and resilience to psychosis.


Asunto(s)
Trastornos Psicóticos , Migrantes , Masculino , Humanos , Adolescente , Femenino , Estudios Longitudinales , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Factores de Riesgo , Síntomas Prodrómicos
3.
Soc Psychiatry Psychiatr Epidemiol ; 57(7): 1379-1388, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35113189

RESUMEN

PURPOSE: Bullying is associated with a heightened risk for poor outcomes, including psychosis. This study aimed to replicate previous findings on bullying prevalence in clinical high-risk (CHR) individuals, to assess the longitudinal course of clinical and functional variables between bullied and non-bullied CHR and the association of bullying with premorbid functioning, clinical outcome, transition to psychosis and risk of violence. METHODS: The sample consisted of 691 CHR participants and 96 healthy controls. Participants reported whether they had experienced bullying and how long it had lasted. Assessments included DSM-5 diagnoses, attenuated psychotic symptoms, negative symptoms, social and role functioning, depression, stress, premorbid functioning, and risk of violence. The bullied and non-bullied CHR groups were compared at baseline and further longitudinally on clinical and functioning variables and transition to psychosis. RESULTS: Bullying was more prevalent among CHR individuals than healthy controls. Bullied CHR had a higher prevalence of PTSD and more severe depression and stress at baseline than non-bullied CHR. There was no impact of bullying on clinical and functional variables over time. Bullying was not related to final clinical status or transition to psychosis. However, bullied participants had poorer premorbid functioning and a greater risk of violence. CONCLUSION: While bullying may not impact the likelihood of CHR individuals to transition to psychosis, it may be a risk factor for development of the at-risk state and may be related to a greater risk of violence. Future studies should consider bullying perpetration among CHR individuals.


Asunto(s)
Acoso Escolar , Trastornos Psicóticos , Estudios de Cohortes , Humanos , Síntomas Prodrómicos , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Factores de Riesgo
4.
Mol Psychiatry ; 25(10): 2431-2440, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-30410064

RESUMEN

The emergence of prodromal symptoms of schizophrenia and their evolution into overt psychosis may stem from an aberrant functional reorganization of the brain during adolescence. To examine whether abnormalities in connectome organization precede psychosis onset, we performed a functional connectome analysis in a large cohort of medication-naive youth at risk for psychosis from the Shanghai At Risk for Psychosis (SHARP) study. The SHARP program is a longitudinal study of adolescents and young adults at Clinical High Risk (CHR) for psychosis, conducted at the Shanghai Mental Health Center in collaboration with neuroimaging laboratories at Harvard and MIT. Our study involved a total of 251 subjects, including 158 CHRs and 93 age-, sex-, and education-matched healthy controls. During 1-year follow-up, 23 CHRs developed psychosis. CHRs who would go on to develop psychosis were found to show abnormal modular connectome organization at baseline, while CHR non-converters did not. In all CHRs, abnormal modular connectome organization at baseline was associated with a threefold conversion rate. A region-specific analysis showed that brain regions implicated in early-course schizophrenia, including superior temporal gyrus and anterior cingulate cortex, were most abnormal in terms of modular assignment. Our results show that functional changes in brain network organization precede the onset of psychosis and may drive psychosis development in at-risk youth.


Asunto(s)
Conectoma , Trastornos Psicóticos/diagnóstico , Adolescente , Adulto , Niño , China , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Síntomas Prodrómicos , Pronóstico , Trastornos Psicóticos/diagnóstico por imagen , Trastornos Psicóticos/patología , Trastornos Psicóticos/fisiopatología , Esquizofrenia/patología , Esquizofrenia/fisiopatología , Adulto Joven
5.
Soc Psychiatry Psychiatr Epidemiol ; 56(6): 943-952, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33399885

RESUMEN

PURPOSE: Migrant status is one of the most replicated and robust risk factors for developing a psychotic disorder. This study aimed to determine whether migrant status in people identified as Ultra-High Risk for Psychosis (UHR) was associated with risk of transitioning to a full-threshold psychotic disorder. METHODS: Hazard ratios for the risk of transition were calculated from five large UHR cohorts (n = 2166) and were used to conduct a meta-analysis using the generic inverse-variance method using a random-effects model. RESULTS: 2166 UHR young people, with a mean age of 19.1 years (SD ± 4.5) were included, of whom 221 (10.7%) were first-generation migrants. A total of 357 young people transitioned to psychosis over a median follow-up time of 417 days (I.Q.R.147-756 days), representing 17.0% of the cohort. The risk of transition to a full-threshold disorder was not increased for first-generation migrants, (HR = 1.08, 95% CI 0.62-1.89); however, there was a high level of heterogeneity between studies The hazard ratio for second-generation migrants to transition to a full-threshold psychotic disorder compared to the remainder of the native-born population was 1.03 (95% CI 0.70-1.51). CONCLUSIONS: This meta-analysis did not find a statistically significant association between migrant status and an increased risk for transition to a full-threshold psychotic disorder; however, several methodological issues could explain this finding. Further research should focus on examining the risk of specific migrant groups and also ensuring that migrant populations are adequately represented within UHR clinics.


Asunto(s)
Trastornos Psicóticos , Migrantes , Adolescente , Adulto , Estudios de Cohortes , Humanos , Modelos de Riesgos Proporcionales , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/epidemiología , Factores de Riesgo , Adulto Joven
6.
Cereb Cortex ; 29(3): 1263-1279, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29522112

RESUMEN

While graph theoretical modeling has dramatically advanced our understanding of complex brain systems, the feasibility of aggregating connectomic data in large imaging consortia remains unclear. Here, using a battery of cognitive, emotional and resting fMRI paradigms, we investigated the generalizability of functional connectomic measures across sites and sessions. Our results revealed overall fair to excellent reliability for a majority of measures during both rest and tasks, in particular for those quantifying connectivity strength, network segregation and network integration. Processing schemes such as node definition and global signal regression (GSR) significantly affected resulting reliability, with higher reliability detected for the Power atlas (vs. AAL atlas) and data without GSR. While network diagnostics for default-mode and sensori-motor systems were consistently reliable independently of paradigm, those for higher-order cognitive systems were reliable predominantly when challenged by task. In addition, based on our present sample and after accounting for observed reliability, satisfactory statistical power can be achieved in multisite research with sample size of approximately 250 when the effect size is moderate or larger. Our findings provide empirical evidence for the generalizability of brain functional graphs in large consortia, and encourage the aggregation of connectomic measures using multisite and multisession data.


Asunto(s)
Encéfalo/fisiología , Conectoma , Emociones/fisiología , Imagen por Resonancia Magnética , Memoria/fisiología , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Memoria Episódica , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Adulto Joven
7.
Neurobiol Dis ; 131: 104353, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30582983

RESUMEN

Schizophrenia is associated with cognitive deficits across all stages of the illness (i.e., high risk, first episode, early and chronic phases). Identifying the underlying neurobiological mechanisms of these deficits is an important area of scientific inquiry. Here, we selectively review evidence regarding the pattern of deficits across the developmental trajectory of schizophrenia using the five cognitive domains identified by the Research Domain Criteria (RDoC) initiative. We also report associated findings from neuroimaging studies. We suggest that most cognitive domains are affected across the developmental trajectory, with corresponding brain structural and/or functional differences. The idea of a common mechanism driving these deficits is discussed, along with implications for cognitive treatment in schizophrenia.


Asunto(s)
Encéfalo/fisiopatología , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Esquizofrenia/complicaciones , Esquizofrenia/fisiopatología , Encéfalo/patología , Trastornos del Conocimiento/patología , Humanos , Esquizofrenia/patología
8.
Psychol Med ; 49(10): 1670-1677, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30176955

RESUMEN

BACKGROUND: Much of the interest in youth at clinical high risk (CHR) of psychosis has been in understanding conversion. Recent literature has suggested that less than 25% of those who meet established criteria for being at CHR of psychosis go on to develop a psychotic illness. However, little is known about the outcome of those who do not make the transition to psychosis. The aim of this paper was to examine clinical symptoms and functioning in the second North American Prodrome Longitudinal Study (NAPLS 2) of those individuals whose by the end of 2 years in the study had not developed psychosis. METHODS: In NAPLS-2 278 CHR participants completed 2-year follow-ups and had not made the transition to psychosis. At 2-years the sample was divided into three groups - those whose symptoms were in remission, those who were still symptomatic and those whose symptoms had become more severe. RESULTS: There was no difference between those who remitted early in the study compared with those who remitted at one or 2 years. At 2-years, those in remission had fewer symptoms and improved functioning compared with the two symptomatic groups. However, all three groups had poorer social functioning and cognition than healthy controls. CONCLUSIONS: A detailed examination of the clinical and functional outcomes of those who did not make the transition to psychosis did not contribute to predicting who may make the transition or who may have an earlier remission of attenuated psychotic symptoms.


Asunto(s)
Progresión de la Enfermedad , Síntomas Prodrómicos , Trastornos Psicóticos/epidemiología , Adolescente , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , América del Norte/epidemiología , Remisión Espontánea , Riesgo , Adulto Joven
9.
Psychol Med ; 49(12): 1990-1998, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30213278

RESUMEN

BACKGROUND: This study aim to derive and validate a simple and well-performing risk calculator (RC) for predicting psychosis in individual patients at clinical high risk (CHR). METHODS: From the ongoing ShangHai-At-Risk-for-Psychosis (SHARP) program, 417 CHR cases were identified based on the Structured Interview for Prodromal Symptoms (SIPS), of whom 349 had at least 1-year follow-up assessment. Of these 349 cases, 83 converted to psychosis. Logistic regression was used to build a multivariate model to predict conversion. The area under the receiver operating characteristic (ROC) curve (AUC) was used to test the effectiveness of the SIPS-RC. Second, an independent sample of 100 CHR subjects was recruited based on an identical baseline and follow-up procedures to validate the performance of the SIPS-RC. RESULTS: Four predictors (each based on a subset of SIPS-based items) were used to construct the SIPS-RC: (1) functional decline; (2) positive symptoms (unusual thoughts, suspiciousness); (3) negative symptoms (social anhedonia, expression of emotion, ideational richness); and (4) general symptoms (dysphoric mood). The SIPS-RC showed moderate discrimination of subsequent transition to psychosis with an AUC of 0.744 (p < 0.001). A risk estimate of 25% or higher had around 75% accuracy for predicting psychosis. The personalized risk generated by the SIPS-RC provided a solid estimate of conversion outcomes in the independent validation sample, with an AUC of 0.804 [95% confidence interval (CI) 0.662-0.951]. CONCLUSION: The SIPS-RC, which is simple and easy to use, can perform in the same manner as the NAPLS-2 RC in the Chinese clinical population. Such a tool may be used by clinicians to counsel appropriately their patients about clinical monitor v. potential treatment options.


Asunto(s)
Síntomas Prodrómicos , Trastornos Psicóticos/diagnóstico , Medición de Riesgo/estadística & datos numéricos , Adolescente , Adulto , Área Bajo la Curva , China , Progresión de la Enfermedad , Femenino , Humanos , Modelos Logísticos , Masculino , Análisis Multivariante , Curva ROC , Reproducibilidad de los Resultados , Medición de Riesgo/métodos , Factores de Riesgo , Adulto Joven
10.
Soc Psychiatry Psychiatr Epidemiol ; 54(3): 291-301, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30488086

RESUMEN

PURPOSE: The current study evaluates the demographic, clinical, and neurocognitive characteristics of a recruited FEP research sample, a research control group, and a FEP clinic sample that were assessed and treated within the same center and time period. METHODS: This study utilized data collected through an observational study and a retrospective chart review. Samples were ascertained in the Longitudinal Assessment and Monitoring of Clinical Status and Brain Function in Adolescents and Adults study and the Prevention and Recovery in Early Psychosis clinic. FEP clinic patients (n = 77), FEP research participants (n = 44), and age-matched controls (n = 38) were assessed using the MATRICS consensus cognitive battery and global functioning social and role scales. Between-group differences were assessed via one-way ANOVA and Chi-square analyses. RESULTS: No significant differences were observed between groups with regard to age and gender. The FEP research sample had a higher proportion of white participants, better social and role functioning, and better neurocognitive performance when compared with the FEP clinical population. The clinic sample also had more diagnostic variability and higher prevalence of substance use disorders relative to the FEP research sample. CONCLUSIONS: Researchers should be aware of how study design and recruitment practices may impact the representativeness of samples, with particular concern for equal representation of racial minorities and patients with more severe illness. Studies should be designed to minimize burden to promote a wider range of participation.


Asunto(s)
Cognición/fisiología , Trastornos Psicóticos/psicología , Adolescente , Adulto , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Estudios Retrospectivos , Adulto Joven
11.
J Int Neuropsychol Soc ; 24(1): 91-103, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28774351

RESUMEN

OBJECTIVES: Studies suggest that impairments in some of the same domains of cognition occur in different neuropsychiatric conditions, including those known to share genetic liability. Yet, direct, multi-disorder cognitive comparisons are limited, and it remains unclear whether overlapping deficits are due to comorbidity. We aimed to extend the literature by examining cognition across different neuropsychiatric conditions and addressing comorbidity. METHODS: Subjects were 486 youth consecutively referred for neuropsychiatric evaluation and enrolled in the Longitudinal Study of Genetic Influences on Cognition. First, we assessed general ability, reaction time variability (RTV), and aspects of executive functions (EFs) in youth with non-comorbid forms of attention-deficit/hyperactivity disorder (ADHD), mood disorders and autism spectrum disorder (ASD), as well as in youth with psychosis. Second, we determined the impact of comorbid ADHD on cognition in youth with ASD and mood disorders. RESULTS: For EFs (working memory, inhibition, and shifting/ flexibility), we observed weaknesses in all diagnostic groups when participants' own ability was the referent. Decrements were subtle in relation to published normative data. For RTV, weaknesses emerged in youth with ADHD and mood disorders, but trend-level results could not rule out decrements in other conditions. Comorbidity with ADHD did not impact the pattern of weaknesses for youth with ASD or mood disorders but increased the magnitude of the decrement in those with mood disorders. CONCLUSIONS: Youth with ADHD, mood disorders, ASD, and psychosis show EF weaknesses that are not due to comorbidity. Whether such cognitive difficulties reflect genetic liability shared among these conditions requires further study. (JINS, 2018, 24, 91-103).


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Trastorno del Espectro Autista/fisiopatología , Disfunción Cognitiva/fisiopatología , Función Ejecutiva/fisiología , Inteligencia/fisiología , Trastornos del Humor/fisiopatología , Trastornos Psicóticos/fisiopatología , Tiempo de Reacción/fisiología , Adolescente , Adulto , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Trastorno del Espectro Autista/epidemiología , Niño , Disfunción Cognitiva/epidemiología , Comorbilidad , Femenino , Humanos , Estudios Longitudinales , Masculino , Trastornos del Humor/epidemiología , Trastornos Psicóticos/epidemiología , Adulto Joven
12.
Dev Psychopathol ; 30(1): 39-47, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28420458

RESUMEN

The developmental course of daily functioning prior to first psychosis-onset remains poorly understood. This study explored age-related periods of change in social and role functioning. The longitudinal study included youth (aged 12-23, mean follow-up years = 1.19) at clinical high risk (CHR) for psychosis (converters [CHR-C], n = 83; nonconverters [CHR-NC], n = 275) and a healthy control group (n = 164). Mixed-model analyses were performed to determine age-related differences in social and role functioning. We limited our analyses to functioning before psychosis conversion; thus, data of CHR-C participants gathered after psychosis onset were excluded. In controls, social and role functioning improved over time. From at least age 12, functioning in CHR was poorer than in controls, and this lag persisted over time. Between ages 15 and 18, social functioning in CHR-C stagnated and diverged from that of CHR-NC, who continued to improve (p = .001). Subsequently, CHR-C lagged behind in improvement between ages 21 and 23, further distinguishing them from CHR-NC (p < .001). A similar period of stagnation was apparent for role functioning, but to a lesser extent (p = .007). The results remained consistent when we accounted for the time to conversion. Our findings suggest that CHR-C start lagging behind CHR-NC in social and role functioning in adolescence, followed by a period of further stagnation in adulthood.


Asunto(s)
Trastornos Psicóticos/psicología , Ajuste Social , Adolescente , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Adulto Joven
13.
J Clin Child Adolesc Psychol ; 47(1): 69-78, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-27705009

RESUMEN

Early intervention for psychotic disorders, a growing international priority, typically targets help-seeking populations with emerging psychotic ("positive") symptoms. We assessed the nature of and degree to which treatment of individuals at high risk for psychosis preceded or followed the onset of positive symptoms. The North American Prodrome Longitudinal Study-2 collected psychosocial treatment histories for 745 (98%) of 764 high-risk participants (M age = 18.9, 57% male, 57.5% Caucasian, 19.1% Hispanic) recruited from 8 North American communities. Similar to prior findings, 82% of participants reported psychosocial treatment prior to baseline assessment, albeit with significant variability across sites (71%-96%). Participants first received treatment a median of 1.7 years prior to the onset of a recognizable psychosis-risk syndrome. Only one fourth sought initial treatment in the year following syndrome onset. Although mean sample age differed significantly by site, age at initial treatment (M = 14.1, SD = 5.0) did not. High rates of early treatment prior to syndrome onset make sense in light of known developmental precursors to psychotic disorders but are inconsistent with the low rates of treatment retrospectively reported by first-episode psychosis samples. Findings suggest that psychosis risk studies and clinics may need to more actively recruit and engage symptomatic but non-help-seeking individuals and that community clinicians be better trained to recognize both positive and nonspecific indicators of emerging psychosis. Improved treatments for nonspecific symptoms, as well as the characteristic attenuated positive symptoms, are needed.


Asunto(s)
Trastornos Psicóticos/terapia , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , América del Norte/epidemiología , Trastornos Psicóticos/diagnóstico , Estudios Retrospectivos , Adulto Joven
14.
Neuroimage ; 161: 1-8, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28818692

RESUMEN

Auditory working memory (WM) processing in everyday acoustic environments depends on our ability to maintain relevant information online in our minds, and to suppress interference caused by competing incoming stimuli. A challenge in communication settings is that the relevant content and irrelevant inputs may emanate from a common source, such as a talkative conversationalist. An open question is how the WM system deals with such interference. Will the distracters become inadvertently filtered before processing for meaning because the primary WM operations deplete all available processing resources? Or are they suppressed post perceptually, through an active control process? We tested these alternative hypotheses by measuring magnetoencephalography (MEG), EEG, and functional MRI (fMRI) during a phonetic auditory continuous performance task. Contextual WM maintenance load was manipulated by adjusting the number of "filler" letter sounds in-between cue and target letter sounds. Trial-to-trial variability of pre- and post-stimulus activations in fMRI-informed cortical MEG/EEG estimates was analyzed within and across 14 subjects using generalized linear mixed effect (GLME) models. High contextual WM maintenance load suppressed left auditory cortex (AC) activations around 250-300 ms after the onset of irrelevant phonetic sounds. This effect coincided with increased 10-14 Hz alpha-range oscillatory functional connectivity between the left dorsolateral prefrontal cortex (DLPFC) and left AC. Suppression of AC responses to irrelevant sounds during active maintenance of the task context also correlated with increased pre-stimulus 7-15 Hz alpha power. Our results suggest that under high auditory WM load, irrelevant sounds are suppressed through a "late" active suppression mechanism, which prevents short-term consolidation of irrelevant information without affecting the initial screening of potentially meaningful stimuli. The results also suggest that AC alpha oscillations play an inhibitory role during auditory WM processing.


Asunto(s)
Ritmo alfa/fisiología , Atención/fisiología , Corteza Auditiva/fisiología , Percepción Auditiva/fisiología , Conectoma/métodos , Magnetoencefalografía/métodos , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/fisiología , Adulto , Corteza Auditiva/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Corteza Prefrontal/diagnóstico por imagen , Adulto Joven
15.
Neuroimage ; 146: 959-970, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27746386

RESUMEN

Recent years have witnessed an increasing number of multisite MRI functional connectivity (fcMRI) studies. While multisite studies provide an efficient way to accelerate data collection and increase sample sizes, especially for rare clinical populations, any effects of site or MRI scanner could ultimately limit power and weaken results. Little data exists on the stability of functional connectivity measurements across sites and sessions. In this study, we assess the influence of site and session on resting state functional connectivity measurements in a healthy cohort of traveling subjects (8 subjects scanned twice at each of 8 sites) scanned as part of the North American Prodrome Longitudinal Study (NAPLS). Reliability was investigated in three types of connectivity analyses: (1) seed-based connectivity with posterior cingulate cortex (PCC), right motor cortex (RMC), and left thalamus (LT) as seeds; (2) the intrinsic connectivity distribution (ICD), a voxel-wise connectivity measure; and (3) matrix connectivity, a whole-brain, atlas-based approach to assessing connectivity between nodes. Contributions to variability in connectivity due to subject, site, and day-of-scan were quantified and used to assess between-session (test-retest) reliability in accordance with Generalizability Theory. Overall, no major site, scanner manufacturer, or day-of-scan effects were found for the univariate connectivity analyses; instead, subject effects dominated relative to the other measured factors. However, summaries of voxel-wise connectivity were found to be sensitive to site and scanner manufacturer effects. For all connectivity measures, although subject variance was three times the site variance, the residual represented 60-80% of the variance, indicating that connectivity differed greatly from scan to scan independent of any of the measured factors (i.e., subject, site, and day-of-scan). Thus, for a single 5min scan, reliability across connectivity measures was poor (ICC=0.07-0.17), but increased with increasing scan duration (ICC=0.21-0.36 at 25min). The limited effects of site and scanner manufacturer support the use of multisite studies, such as NAPLS, as a viable means of collecting data on rare populations and increasing power in univariate functional connectivity studies. However, the results indicate that aggregation of fcMRI data across longer scan durations is necessary to increase the reliability of connectivity estimates at the single-subject level.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Adulto , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/instrumentación , Masculino , Estudios Multicéntricos como Asunto , Vías Nerviosas/fisiología , Reproducibilidad de los Resultados , Adulto Joven
16.
J Int Neuropsychol Soc ; 23(9-10): 881-892, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-29198285

RESUMEN

We review the changing conceptions of schizophrenia over the past 50 years as it became understood as a disorder of brain function and structure in which neurocognitive dysfunction was identified at different illness phases. The centrality of neurocognition has been recognized, especially because neurocognitive deficits are strongly related to social and role functioning in the illness, and as a result neurocognitive measures are used routinely in clinical assessment of individuals with schizophrenia. From the original definitions of the syndrome of schizophrenia in the early 20th century, impaired cognition, especially attention, was considered to be important. Neurocognitive impairments are found in the vast majority of individuals with schizophrenia, and they vary from mild, relatively restricted deficits, to dementia-like syndromes, as early as the first psychotic episode. Neurocognitive deficits are found in the premorbid phase in a substantial minority of pre-teenage youth who later develop schizophrenia, and they apparently worsen by the prodromal, high-risk phase in a majority of those who develop the illness. While there is limited evidence for reversibility of impairments from pharmacological interventions in schizophrenia, promising results have emerged from cognitive remediation studies. Thus, we expect cognitive interventions to play a larger role in schizophrenia in the coming years. Moreover, because youth at risk for schizophrenia can be identified by an emergent high-risk syndrome, earlier interventions might be applied in a pre-emptive way to reduce disability and improve adaptation. The notion of schizophrenia as a developmental neurocognitive disorder with stages opens up a window of possibilities for earlier interventions. (JINS, 2017, 23, 881-892).


Asunto(s)
Discapacidades del Desarrollo/etiología , Trastornos Neurocognitivos/etiología , Esquizofrenia/complicaciones , Psicología del Esquizofrénico , Discapacidades del Desarrollo/historia , Electroencefalografía , Potenciales Evocados/fisiología , Historia del Siglo XX , Humanos , Trastornos Neurocognitivos/diagnóstico por imagen , Neuroimagen , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/historia , Esquizofrenia/terapia
17.
Hum Brain Mapp ; 37(1): 254-61, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26467751

RESUMEN

The characterization of neurodevelopmental aspects of brain alterations require neuroimaging methods that reflect correlates of neurodevelopment, while being robust to other progressive pathological processes. Newly developed neuroimaging methods for measuring geometrical features of the white matter fall exactly into this category. Our recent work shows that such features, measured in the anterior corpus callosum in diffusion MRI data, correlate with psychosis symptoms in patients with adolescent onset schizophrenia and subside a reversal of normal sexual dimorphism. Here, we test the hypothesis that similar developmental deviations will also be present in nonpsychotic subjects at familial high risk (FHR) for schizophrenia, due to genetic predispositions. Demonstrating such changes would provide a strong indication of neurodevelopmental deviation extant before, and independent of pathological changes occurring after disease onset. We examined the macrostructural geometry of corpus callosum white matter in diffusion MRI data of 35 non-psychotic subjects with genetic (familial) risk for schizophrenia, and 26 control subjects, both male and female. We report a reversal of normal sexual dimorphism in callosal white matter geometry consistent with recent results in adolescent onset schizophrenia. This pattern may be indicative of an error in neurogenesis and a possible trait marker of schizophrenia.


Asunto(s)
Cuerpo Calloso/patología , Trastornos Psicóticos/patología , Esquizofrenia/patología , Caracteres Sexuales , Sustancia Blanca/patología , Adulto , Femenino , Humanos , Imagenología Tridimensional , Masculino , Escalas de Valoración Psiquiátrica , Adulto Joven
18.
Br J Psychiatry ; 208(2): 120-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26585100

RESUMEN

BACKGROUND: There is inconsistent evidence regarding the influence of general cognitive abilities on the long-term course of depression. AIMS: To investigate the association between general childhood cognitive abilities and adult depression outcomes. METHOD: We conducted a cohort study using data from 633 participants in the New England Family Study with lifetime depression. Cognitive abilities at age 7 were measured using the Wechsler Intelligence Scale for Children. Depression outcomes were assessed using structured diagnostic interviews administered up to four times in adulthood between ages 17 and 49. RESULTS: In analyses adjusting for demographic factors and parental psychiatric illness, low general cognitive ability (i.e. IQ<85 v. IQ>115) was associated with recurrent depressive episodes (odds ratio (OR) = 2.19, 95% CI 1.20-4.00), longer episode duration (rate ratio 4.21, 95% CI 2.24-7.94), admission to hospital for depression (OR = 3.65, 95% CI 1.34-9.93) and suicide ideation (OR = 3.79, 95% CI 1.79-8.02) and attempt (OR = 4.94, 95% CI 1.67-14.55). CONCLUSIONS: Variation in cognitive abilities, predominantly within the normal range and established early in childhood, may confer long-term vulnerability for prolonged and severe depression. The mechanisms underlying this vulnerability need to be established to improve the prognosis of depression among individuals with lower cognitive abilities.


Asunto(s)
Cognición , Depresión/psicología , Ideación Suicida , Intento de Suicidio/estadística & datos numéricos , Adolescente , Adulto , Niño , Enfermedad Crónica , Estudios de Cohortes , Femenino , Humanos , Pruebas de Inteligencia , Modelos Logísticos , Masculino , Massachusetts , Persona de Mediana Edad , Pronóstico , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Adulto Joven
19.
J Child Psychol Psychiatry ; 57(4): 462-71, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26411927

RESUMEN

BACKGROUND: Evidence that different neuropsychiatric conditions share genetic liability has increased interest in phenotypes with 'cross-disorder' relevance, as they may contribute to revised models of psychopathology. Cognition is a promising construct for study; yet, evidence that the same cognitive functions are impaired across different forms of psychopathology comes primarily from separate studies of individual categorical diagnoses versus controls. Given growing support for dimensional models that cut across traditional diagnostic boundaries, we aimed to determine, within a single cohort, whether performance on measures of executive functions (EFs) predicted dimensions of different psychopathological conditions known to share genetic liability. METHODS: Data are from 393 participants, ages 8-17, consecutively enrolled in the Longitudinal Study of Genetic Influences on Cognition (LOGIC). This project is conducting deep phenotyping and genomic analyses in youth referred for neuropsychiatric evaluation. Using structural equation modeling, we examined whether EFs predicted variation in core dimensions of the autism spectrum disorder, bipolar illness, and schizophrenia (including social responsiveness, mania/emotion regulation, and positive symptoms of psychosis, respectively). RESULTS: We modeled three cognitive factors (working memory, shifting, and executive processing speed) that loaded on a second-order EF factor. The EF factor predicted variation in our three target traits, but not in a negative control (somatization). Moreover, this EF factor was primarily associated with the overlapping (rather than unique) variance across the three outcome measures, suggesting that it related to a general increase in psychopathology symptoms across those dimensions. CONCLUSIONS: Findings extend support for the relevance of cognition to neuropsychiatric conditions that share underlying genetic risk. They suggest that higher-order cognition, including EFs, relates to the dimensional spectrum of each of these disorders and not just the clinical diagnoses. Moreover, results have implications for bottom-up models linking genes, cognition, and a general psychopathology liability.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Trastorno Bipolar/fisiopatología , Función Ejecutiva/fisiología , Esquizofrenia/fisiopatología , Adolescente , Trastorno del Espectro Autista/clasificación , Trastorno Bipolar/clasificación , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Esquizofrenia/clasificación
20.
J Int Neuropsychol Soc ; 22(10): 1026-1037, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27903327

RESUMEN

BACKGROUND: The degree of overlap between schizophrenia (SCZ) and affective psychosis (AFF) has been a recurring question since Kraepelin's subdivision of the major psychoses. Studying nonpsychotic relatives allows a comparison of disorder-associated phenotypes, without potential confounds that can obscure distinctive features of the disorder. Because attention and working memory have been proposed as potential endophenotypes for SCZ and AFF, we compared these cognitive features in individuals at familial high-risk (FHR) for the disorders. METHODS: Young, unmedicated, first-degree relatives (ages, 13-25 years) at FHR-SCZ (n=41) and FHR-AFF (n=24) and community controls (CCs, n=54) were tested using attention and working memory versions of the Auditory Continuous Performance Test. To determine if schizotypal traits or current psychopathology accounted for cognitive deficits, we evaluated psychosis proneness using three Chapman Scales, Revised Physical Anhedonia, Perceptual Aberration, and Magical Ideation, and assessed psychopathology using the Hopkins Symptom Checklist -90 Revised. RESULTS: Compared to controls, the FHR-AFF sample was significantly impaired in auditory vigilance, while the FHR-SCZ sample was significantly worse in working memory. Both FHR groups showed significantly higher levels of physical anhedonia and some psychopathological dimensions than controls. Adjusting for physical anhedonia, phobic anxiety, depression, psychoticism, and obsessive-compulsive symptoms eliminated the FHR-AFF vigilance effects but not the working memory deficits in FHR-SCZ. CONCLUSIONS: The working memory deficit in FHR-SZ was the more robust of the cognitive impairments after accounting for psychopathological confounds and is supported as an endophenotype. Examination of larger samples of people at familial risk for different psychoses remains necessary to confirm these findings and to clarify the role of vigilance in FHR-AFF. (JINS, 2016, 22, 1026-1037).


Asunto(s)
Trastornos Psicóticos Afectivos/fisiopatología , Atención/fisiología , Percepción Auditiva/fisiología , Disfunción Cognitiva/fisiopatología , Endofenotipos , Familia , Memoria a Corto Plazo/fisiología , Esquizofrenia/fisiopatología , Adolescente , Adulto , Trastornos Psicóticos Afectivos/complicaciones , Disfunción Cognitiva/etiología , Femenino , Humanos , Masculino , Riesgo , Esquizofrenia/complicaciones , Adulto Joven
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