Publications by authors named "Jean Addington"

Background: Attention Deficit Hyperactivity Disorder (ADHD) affects a significant proportion of the population and is associated with numerous adverse outcomes including lower educational attainment, occupational challenges, increased substance use, and various mental health issues including psychosis. This study examined the demographic, clinical, cognitive, social cognitive, and functional differences between youth at clinical high-risk (CHR) for psychosis with and without comorbid ADHD.

Method: Data were drawn from the North American Prodrome Longitudinal Studies (NAPLS2 and NAPLS3), which included 764 and 710 CHR individuals, respectively.

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Mismatch negativity (MMN) event-related potential (ERP) component reduction, indexing N-methyl-D-aspartate receptor (NMDAR)-dependent auditory echoic memory and short-term plasticity, is a well-established biomarker of schizophrenia that is sensitive to psychosis risk among individuals at clinical high-risk (CHR-P). Based on the NMDAR-hypofunction model of schizophrenia, NMDAR-dependent plasticity is predicted to contribute to aberrant neurodevelopmental processes involved in the pathogenesis of schizophrenia during late adolescence or young adulthood, including gray matter loss. Moreover, stress and inflammation disrupt plasticity.

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Identifying biomarkers for serious mental illnesses (SMI) has significant implications for prevention and early intervention. In the current study, changes in whole brain structural and functional connectomes were investigated in youth at transdiagnostic risk over a one-year period. Based on clinical assessments, participants were assigned to one of 5 groups: healthy controls (HC; n = 33), familial risk for serious mental illness (stage 0; n = 31), mild symptoms (stage 1a; n = 37), attenuated syndromes (stage 1b; n = 61), or discrete disorder (transition; n = 9).

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Background And Hypothesis: Studying individuals at Clinical High Risk (CHR) for psychosis provides an opportunity to examine protective factors that predict resilient outcomes. Here, we present a model for the study of protective factors in CHR participants at the very highest risk for psychotic conversion based on the Psychosis Risk Calculator.

Study Design: CHR participants (N = 572) from NAPLS3 were assessed on the Risk Calculator.

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Article Synopsis
  • This study looked at how living in diverse neighborhoods affects young people at risk for schizophrenia compared to those who are not.
  • Researchers found that living in neighborhoods with lots of different racial and ethnic groups can lead to fewer symptoms of mental health issues for some young people.
  • They also discovered that experiences like being bullied and discrimination can play a role in how these feelings are affected by neighborhood diversity.
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Introduction: Research has established that adverse childhood experiences (ACEs) confer risk for psychiatric diagnoses, and that protective factors moderate this association. Investigation into the effect of protective factors in the relationship between ACEs and internalizing disorders (e.g.

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Background: Although the clinical high risk for psychosis (CHR-P) criteria are widely used to ascertain individuals at heightened risk for imminent onset of psychosis, it remains controversial whether CHR-P status defines a diagnostic construct in its own right. In a previous study, CHR-P nonconverters were observed to follow 3 distinct trajectories in symptoms and functioning: remission, partial remission, and maintenance of symptoms and functional impairments at subthreshold levels of intensity.

Methods: Here, we utilized the NAPLS3 (North American Prodrome Longitudinal Study phase 3) sample (N = 806) to determine whether 1) the same trajectory groups can be detected when assessing symptoms at 2-month intervals over an 8-month period and 2) the resulting trajectory groups differ from each other and from healthy control participants and converting CHR-P cases in terms of risk factors, comorbidities, and functional outcomes.

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Negative symptoms are often found in youth at clinical high risk (CHR) for psychosis. The present study explored the feasibility of using tDCS in conjunction with CBT in the treatment of negative symptoms in 5 youths at CHR. We sought to determine whether the protocol was feasible given the requirement for repeated visits over a three-week period, and to determine if measures of neurobiological change could be included, both acutely and following three weeks of stimulation.

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Schizophrenia spectrum disorders (SSDs) are characterized by substantial clinical and genetic heterogeneity. Multiple recurrent copy number variants (CNVs) increase risk for SSDs; however, how known risk CNVs and broader genome-wide CNVs influence clinical variability is unclear. The current study examined associations between borderline intellectual functioning or childhood-onset psychosis, known risk CNVs, and burden of deletions affecting genes in 18 previously validated neurodevelopmental gene-sets in 618 SSD individuals.

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Background: 22q11.2 deletion syndrome (22qDel) is a copy number variant that is associated with psychosis and other neurodevelopmental disorders. Adolescents who are at clinical high risk for psychosis (CHR) are identified based on the presence of subthreshold psychosis symptoms.

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Background: Neurocognitive impairment is a well-known phenomenon in schizophrenia that begins prior to psychosis onset. Connectome-wide association studies have inconsistently linked cognitive performance to resting-state functional magnetic resonance imaging. We hypothesized that a carefully selected cognitive instrument and refined population would allow identification of reliable brain-behavior associations with connectome-wide association studies.

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Sex differences have been observed in individuals with schizophrenia and for those at clinical high risk (CHR) for psychosis. However, specific differences in CHR individuals who transition to psychosis remain inconsistent and understudied. This study aimed to investigate sex differences in 156 CHR individuals who made the transition to psychosis.

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The prodromal phase of schizophrenia provides an optimal opportunity to mitigate the profound functional disability that is often associated with fully expressed psychosis. Considerable evidence supports the importance of neurocognition in the development of interpersonal (social) and academic (role) skills. Further findings from adolescents and young adults at clinical high risk for developing psychosis (CHRP) suggest that treatment for functioning might be most effective when targeting early and specific neurocognitive deficits.

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Background And Hypothesis: The Structured Interview for Psychosis-Risk Syndromes (SIPS) and other assessments of psychosis risk define clinical high risk for psychosis (CHR) by the presence of attenuated psychotic symptoms. Despite extensive research on attenuated psychotic symptoms, substantial questions remain about their internal psychometric structure and relationships to comorbid non-psychotic symptoms.

Study Design: Hierarchical and bifactor models were developed for the SIPS in a large CHR sample (NAPLS-3, N = 787) and confirmed through preregistered replication in an independent sample (NAPLS-2, N = 1043).

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Background And Hypothesis: Social and academic adjustment deteriorate in the years preceding a psychotic disorder diagnosis. Analyses of premorbid adjustment have recently been extended into the clinical high risk for psychosis (CHR) syndrome to identify risk factors and developmental pathways toward psychotic disorders. Work so far has been at the between-person level, which has constrained analyses of premorbid adjustment, clinical covariates, and conversion to psychosis.

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Article Synopsis
  • - The study investigates how major depressive disorder (MDD) affects brain structure and cognitive function, particularly looking at how these changes relate to normal brain development and aging in adolescents and adults.
  • - Researchers analyzed brain data from 304 participants with MDD and 236 without, finding that individuals with MDD had lower brain centile scores, indicating atypical brain aging, and those scores were linked to working memory only in the control group.
  • - The findings suggest that MDD is associated with unusual brain development and aging, but severity of depression and childhood maltreatment did not significantly influence brain measurements or treatment responses.
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Aim: There is limited research on the effects of sociodemographic and socioeconomic factors on treatment outcomes in youth at clinical high risk for psychosis (CHRp). This study examined sociodemographic factors that may affect functional outcomes within this population. Specifically, we investigated the influence of race/ethnicity (dichotomized as non-Hispanic whites [NHW] vs.

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Introduction: Negative symptoms impact the quality of life of individuals with psychosis and current treatment options for negative symptoms have limited effectiveness. Previous studies have demonstrated that complement and coagulation pathway protein levels are related to later psychotic experiences, psychotic disorder, and functioning. However, the prognostic relationship between complement and coagulation proteins and negative symptoms is poorly characterised.

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The Hierarchical Taxonomy of Psychopathology (HiTOP) consortium's transdiagnostic dimensional model of psychopathology has considerable support; however, this model has been underresearched in individuals at clinical high risk for psychosis (CHR-P), a population that may advance the model. CHR-P individuals not only have attenuated psychotic symptoms that vary in severity, but also have many comorbid diagnoses and varied clinical outcomes, including disorders with uncertain relations to HiTOP (e.g.

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This article describes the rationale, aims, and methodology of the Accelerating Medicines Partnership® Schizophrenia (AMP® SCZ). This is the largest international collaboration to date that will develop algorithms to predict trajectories and outcomes of individuals at clinical high risk (CHR) for psychosis and to advance the development and use of novel pharmacological interventions for CHR individuals. We present a description of the participating research networks and the data processing analysis and coordination center, their processes for data harmonization across 43 sites from 13 participating countries (recruitment across North America, Australia, Europe, Asia, and South America), data flow and quality assessment processes, data analyses, and the transfer of data to the National Institute of Mental Health (NIMH) Data Archive (NDA) for use by the research community.

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Aim: Schizophrenia is a leading cause of disability worldwide; early detection and intervention are critical. Early in their illness, individuals at clinical high-risk (CHR) for psychosis have subthreshold psychotic symptoms that are often derogatory and self-directed. We hypothesized that CHR participants with negative self-reference (NSR) as a component of subthreshold psychosis would also have higher levels of social anxiety and depression, lower self-esteem and lower social/role/global functioning as compared with CHR participants without NSR.

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We examine structural brain characteristics across three diagnostic categories: at risk for serious mental illness; first-presenting episode and recurrent major depressive disorder (MDD). We investigate whether the three diagnostic groups display a stepwise pattern of brain changes in the cortico-limbic regions. Integrated clinical and neuroimaging data from three large Canadian studies were pooled (total n = 622 participants, aged 12-66 years).

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