Browsing by Author "Crossley, Nicolas A."
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- ItemChildhood adversity increases risk of psychotic experiences in patients with substance use disorder(ELSEVIER IRELAND LTD, 2022) Borquez-Infante, Ignacio; Vasquez, Javiera; Dupre, Sofia; Undurraga, Eduardo A.; Crossley, Nicolas A.; Undurraga, JuanIntroduction: Adverse childhood experiences (ACEs) increase the risk of psychotic experiences (PE), but little is known about heterogeneities of this association in different developmental stages, dimensions, or whether they are affected by substance use disorder (SUD). This study examines the association between different types of ACEs at various developmental stages and lifetime PE in patients with SUD in Chile.Methods: We included 399 consenting adults in outpatient or residential SUD treatment programs. Sociodemo-graphic data and information about PE and ACEs were obtained by trained clinical psychologists.Results: Patients reporting PE experienced more ACEs compared to patients without PE (4.2 versus 3.4). They also experienced more complex adversities (41.8% versus 25.1%), had more psychiatric comorbidities (85% versus 70.4%), and reported using more substances (mean 4.5 versus 3.9). Adjusted association between ACEs and PE showed the highest OR for arrests (1.88), sexual abuse (1.81), alcohol abuse by parents (1.48), school exclusion (1.39), foster or residential care (18.3).Conclusion: Early exposure to ACEs is a risk factor for later PE among patients with SUD. Type of ACE and the period when they occurred is important, suggesting the existence of critical periods where the individual is more susceptible to adverse environmental stimuli.
- ItemDysconnectivity in Schizophrenia Revisited: Abnormal Temporal Organization of Dynamic Functional Connectivity in Patients With a First Episode of Psychosis(2023) Ramirez-Mahaluf, Juan P.; Tepper, Angeles; Maria Alliende, Luz; Mena, Carlos; Castaneda, Carmen Paz; Iruretagoyena, Barbara; Nachar, Ruben; Reyes-Madrigal, Francisco; Leon-Ortiz, Pablo; Mora-Duran, Ricardo; Ossandon, Tomas; Gonzalez-Valderrama, Alfonso; Undurraga, Juan; De la Fuente-Sandoval, Camilo; Crossley, Nicolas A.Background and Hypothesis Abnormal functional connectivity between brain regions is a consistent finding in schizophrenia, including functional magnetic resonance imaging (fMRI) studies. Recent studies have highlighted that connectivity changes in time in healthy subjects. We here examined the temporal changes in functional connectivity in patients with a first episode of psychosis (FEP). Specifically, we analyzed the temporal order in which whole-brain organization states were visited. Study Design Two case-control studies, including in each sample a subgroup scanned a second time after treatment. Chilean sample included 79 patients with a FEP and 83 healthy controls. Mexican sample included 21 antipsychotic-naive FEP patients and 15 healthy controls. Characteristics of the temporal trajectories between whole-brain functional connectivity meta-states were examined via resting-state functional MRI using elements of network science. We compared the cohorts of cases and controls and explored their differences as well as potential associations with symptoms, cognition, and antipsychotic medication doses. Study Results We found that the temporal sequence in which patients' brain dynamics visited the different states was more redundant and segregated. Patients were less flexible than controls in changing their network in time from different configurations, and explored the whole landscape of possible states in a less efficient way. These changes were related to the dose of antipsychotics the patients were receiving. We replicated the relationship with antipsychotic medication in the antipsychotic-naive FEP sample scanned before and after treatment. Conclusions We conclude that psychosis is related to a temporal disorganization of the brain's dynamic functional connectivity, and this is associated with antipsychotic medication use.
- ItemObesity and brain structure in schizophrenia - ENIGMA study in 3021 individuals(2022) McWhinney, Sean R.; Brosch, Katharina; Calhoun, Vince D.; Crespo-Facorro, Benedicto; Crossley, Nicolas A.; Dannlowski, Udo; Dickie, Erin; Dietze, Lorielle M. F.; Donohoe, Gary; Du Plessis, Stefan; Ehrlich, Stefan; Emsley, Robin; Furstova, Petra; Glahn, David C.; Gonzalez-Valderrama, Alfonso; Grotegerd, Dominik; Holleran, Laurena; Kircher, Tilo T. J.; Knytl, Pavel; Kolenic, Marian; Lencer, Rebekka; Nenadic, Igor; Opel, Nils; Pfarr, Julia-Katharina; Rodrigue, Amanda L.; Rootes-Murdy, Kelly; Ross, Alex J.; Sim, Kang; Skoch, Antonin; Spaniel, Filip; Stein, Frederike; Svancer, Patrik; Tordesillas-Gutierrez, Diana; Undurraga, Juan; Vaquez-Bourgon, Javier; Voineskos, Aristotle; Walton, Esther; Weickert, Thomas W.; Weickert, Cynthia Shannon; Thompson, Paul M.; van Erp, Theo G. M.; Turner, Jessica A.; Hajek, TomasSchizophrenia is frequently associated with obesity, which is linked with neurostructural alterations. Yet, we do not understand how the brain correlates of obesity map onto the brain changes in schizophrenia. We obtained MRI-derived brain cortical and subcortical measures and body mass index (BMI) from 1260 individuals with schizophrenia and 1761 controls from 12 independent research sites within the ENIGMA-Schizophrenia Working Group. We jointly modeled the statistical effects of schizophrenia and BMI using mixed effects. BMI was additively associated with structure of many of the same brain regions as schizophrenia, but the cortical and subcortical alterations in schizophrenia were more widespread and pronounced. Both BMI and schizophrenia were primarily associated with changes in cortical thickness, with fewer correlates in surface area. While, BMI was negatively associated with cortical thickness, the significant associations between BMI and surface area or subcortical volumes were positive. Lastly, the brain correlates of obesity were replicated among large studies and closely resembled neurostructural changes in major depressive disorders. We confirmed widespread associations between BMI and brain structure in individuals with schizophrenia. People with both obesity and schizophrenia showed more pronounced brain alterations than people with only one of these conditions. Obesity appears to be a relevant factor which could account for heterogeneity of brain imaging findings and for differences in brain imaging outcomes among people with schizophrenia.
- ItemParsing neurobiological heterogeneity of the clinical high-risk state for psychosis: A pseudo-continuous arterial spin labelling study(2023) Oliver, Dominic; Davies, Cathy; Zelaya, Fernando; Selvaggi, Pierluigi; De Micheli, Andrea; Catalan, Ana; Baldwin, Helen; Arribas, Maite; Modinos, Gemma; Crossley, Nicolas A.; Allen, Paul; Egerton, Alice; Jauhar, Sameer; Howes, Oliver D.; McGuire, Philip; Fusar-Poli, PaoloIntroductionThe impact of the clinical high-risk for psychosis (CHR-P) construct is dependent on accurately predicting outcomes. Individuals with brief limited intermittent psychotic symptoms (BLIPS) have higher risk of developing a first episode of psychosis (FEP) compared to individuals with attenuated psychotic symptoms (APS). Supplementing subgroup stratification with information from candidate biomarkers based on neurobiological parameters, such as resting-state, regional cerebral blood flow (rCBF), may help refine risk estimates. Based on previous evidence, we hypothesized that individuals with BLIPS would exhibit increased rCBF compared to APS in key regions linked to dopaminergic pathways. MethodsData from four studies were combined using ComBat (to account for between-study differences) to analyse rCBF in 150 age- and sex-matched subjects (n = 30 healthy controls [HCs], n = 80 APS, n = 20 BLIPS and n = 20 FEP). Global gray matter (GM) rCBF was examined in addition to region-of-interest (ROI) analyses in bilateral/left/right frontal cortex, hippocampus and striatum. Group differences were assessed using general linear models: (i) alone; (ii) with global GM rCBF as a covariate; (iii) with global GM rCBF and smoking status as covariates. Significance was set at p < 0.05. ResultsWhole-brain voxel-wise analyses and Bayesian ROI analyses were also conducted. No significant group differences were found in global [F(3,143) = 1,41, p = 0.24], bilateral frontal cortex [F(3,143) = 1.01, p = 0.39], hippocampus [F(3,143) = 0.63, p = 0.60] or striatum [F(3,143) = 0.52, p = 0.57] rCBF. Similar null findings were observed in lateralized ROIs (p > 0.05). All results were robust to addition of covariates (p > 0.05). No significant clusters were identified in whole-brain voxel-wise analyses (p > 0.05(FWE)). Weak-to-moderate evidence was found for an absence of rCBF differences between APS and BLIPS in Bayesian ROI analyses. ConclusionOn this evidence, APS and BLIPS are unlikely to be neurobiologically distinct. Due to this and the weak-to-moderate evidence for the null hypothesis, future research should investigate larger samples of APS and BLIPS through collaboration across large-scale international consortia.