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Brown MRG, Agyapong V, Greenshaw AJ, Cribben I, Brett-MacLean P, Drolet J, McDonald-Harker C, Omeje J, Mankowsi M, Noble S, Kitching D, Silverstone PH. After the Fort McMurray wildfire there are significant increases in mental health symptoms in grade 7-12 students compared to controls. BMC Psychiatry 2019; 19:18. [PMID: 30630501 PMCID: PMC6329184 DOI: 10.1186/s12888-018-2007-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 12/27/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND In order to examine the impact of disasters on adolescent mental health, this study compared population mental health survey data from two communities in Alberta, Canada: Fort McMurray, which experienced a major natural disaster, and Red Deer, which did not. METHODS Data from 3070 grade 7-12 students from Fort McMurray, Alberta, Canada (collected in 2017, 18 months after the 2016 wildfire) was compared with data from 2796 grade 7-12 students from Red Deer, Alberta, Canada (collected in 2014). The same measurement scales were used for both surveys. Both of these cities have populations of approximately 100,000, and both cities are located in Alberta, Canada. For this reason, Red Deer is an appropriate non-disaster impacted community to compare to the disaster impacted community of Fort McMurray. RESULTS The results of this comparison demonstrate that mental health symptoms were statistically significantly elevated in the Fort McMurray population when compared to the control population in Red Deer. This occurred for scores consistent with a diagnosis of depression (31% vs. 17%), moderately severe depression (17% vs. 9%), suicidal thinking (16% vs. 4%), and tobacco use (13% vs. 10%). Consistent with there being major mental health impacts from the 2016 Fort McMurray wildfire, self-esteem scores and quality of life scores were also statistically significantly lower in Fort McMurray. While the rates of anxiety disorder were similar (15% vs. 16%), the mean scores on the anxiety scale were slightly higher, with this difference reaching statistical significance. There were no statistical differences in the rates or scores for alcohol or substance use. CONCLUSIONS Our results are consistent with previous findings showing a significant negative impact of disasters on many aspects of adolescent mental, with a particular increase in symptoms related to depression and suicidal thinking. These findings highlight first, the need to identify adolescents most at risk of developing psychiatric symptoms after experiencing the trauma of disaster and second, the importance and necessity of implementing short and long term mental health intervention programs specifically aimed at adolescents, in order to help mitigate the negative effects of disasters on their mental health.
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Howland JG, Greenshaw AJ, Winship IR. Practical Aspects of Animal Models of Psychiatric Disorders. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 2019; 64:3-4. [PMID: 30789052 PMCID: PMC6364137 DOI: 10.1177/0706743718771833] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Brown MRG, Agyapong V, Greenshaw AJ, Cribben I, Brett-MacLean P, Drolet J, McDonald-Harker C, Omeje J, Mankowsi M, Noble S, Kitching DT, Silverstone PH. Significant PTSD and Other Mental Health Effects Present 18 Months After the Fort Mcmurray Wildfire: Findings From 3,070 Grades 7-12 Students. Front Psychiatry 2019; 10:623. [PMID: 31543839 PMCID: PMC6728415 DOI: 10.3389/fpsyt.2019.00623] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 08/05/2019] [Indexed: 11/13/2022] Open
Abstract
Background: The May 2016 wildfire in Fort McMurray, Alberta, Canada forced evacuation of the population of 88,000 individuals and destroyed 10% of the homes. Youth are particularly impacted by disaster. Methods: Eighteen months after the wildfire, Fort McMurray Public and Catholic Schools surveyed 3,252 of the 4,407 students in Grades 7-12 to determine possible long-term psychological impacts. The survey included validated measurement scales for post-traumatic stress disorder (PTSD), depression, anxiety, use of drugs, alcohol, and tobacco, quality of life, self-esteem, and resilience. Data analysis was possible for only 3,070 students, i.e., 70% of the total student population. Anonymized data were analyzed to compare students who directly experienced lesser or greater impact from the wildfire, with greater impact defined as personally seeing the fire or having one's home destroyed. Also, students with greater or lesser scores on the Child and Youth Resilience Measure (CYRM-12) were compared. Results: Of the 3,070 students, 37% met criteria for probable PTSD; 31% met criteria for probable depression, and 17% for probable depression of at least moderate severity; 27% of students met criteria for probable anxiety, and 15% for probable alcohol or substance use disorder; 46% of all students met criteria for one or more probable diagnosis of PTSD, depression, anxiety, or alcohol/substance abuse, and this included students who were both present and not present in Fort McMurray at the time of the wildfire. Students with greater impact from the wildfire exhibited significantly higher scores on measures of PTSD, depression, anxiety, and alcohol/substance use. They also had lower self-esteem and quality of life scores. Students with lower resilience scores exhibited a similar pattern. Conclusions: These findings highlight first the negative impact of disasters on youth mental health, particularly for those who directly experience wildfire, and second the role of resilience on youth mental health, with lower resilience associated with substantially lower mental health outcomes. These results emphasize the need for long-term mental health supports for youth post-disaster, with specific focus on increasing youth resilience, which may serve as a protective factor against effects of disaster on mental health.
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Moosavi S, Nwaka B, Akinjise I, Corbett SE, Chue P, Greenshaw AJ, Silverstone PH, Li XM, Agyapong VIO. Mental Health Effects in Primary Care Patients 18 Months After a Major Wildfire in Fort McMurray: Risk Increased by Social Demographic Issues, Clinical Antecedents, and Degree of Fire Exposure. Front Psychiatry 2019; 10:683. [PMID: 31620033 PMCID: PMC6760025 DOI: 10.3389/fpsyt.2019.00683] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 08/23/2019] [Indexed: 11/13/2022] Open
Abstract
Objectives: To assess prevalence of likely posttraumatic stress disorder (PTSD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) in patients attending the only out-of-hours primary care clinic in Fort McMurray some 18 months following a major fire. Methods: A quantitative cross-sectional survey was used to collect data through self-administered paper-based questionnaires to determine likely PTSD, MDD, and GAD using the PTSD Checklists for Diagnostic and Statistical Manual (DSM) 5, Patient Health Questionnaire (PHQ) 9, and GAD-7, respectively, from residents of Fort McMurray who were impacted by the wildfires. This was carried out eighteen (18) months after a major wildfire, which required the rapid evacuation of the entire city population (approximately 90,000 individuals). Results: We achieved a response rate of 48% and results from the 290 respondents showed the 1 month prevalence rate for likely PTSD was 13.6%, likely MDD was 24.8%, and likely GAD was 18.0%. Compared to self-reported prevalence rates before the wildfire (0%, 15.2%, and 14.5% respectively), these were increased for all diagnoses. After controlling for other factors in a logistic regression model, there were statistically significant associations between individuals who had likely PTSD, MDD, and GAD diagnoses and multiple socio-demographic, clinical, and exposure-related variables as follows: PTSD: History of anxiety disorder and received counselling had odds ratios (ORs) of 5.80 and 7.14, respectively. MDD: Age, witnessed the burning of homes, history of depressive disorder, and receiving low level support from friends and family had ORs of 2.08, 2.29, 4.63, and 2.5, respectively. GAD: Fearful for their lives or the lives of friends/family, history of depressive disorder, and history of anxiety disorder had ORs of 3.52, 3.04, and 2.68, respectively. There were also associations between individuals with a likely psychiatric diagnosis and those who also had likely alcohol or drug abuse/dependence. Conclusion: Our study suggests there are high prevalence rates for mental health and addiction conditions in patients attending the out-of-hours clinic 18 months after the wildfires, with significant associations between multiple variables and likely PTSD, MDD, and GAD. Further studies are needed to explore the impact of population-based mental health interventions on the long-term mental health effects of the wildfires.
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Ng CH, Goodenow MM, Greenshaw AJ, Upshall P, Lam RW. Inclusion of mental health in global economic development. BJPsych Int 2018; 15:74-76. [PMID: 30524132 PMCID: PMC6277955 DOI: 10.1192/bji.2017.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The APEC Mental Health Roadmap has a vision to strengthen mental health and reduce the economic impact of mental illness in the Asia Pacific. To facilitate its implementation, the APEC Digital Hub will heighten exchange and dissemination of best practices in Asia Pacific mental health partnerships, and increase multi-sectoral recognition to invest in mental health to support economic growth.
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Agyapong VIO, Juhás M, Mrklas K, Hrabok M, Omeje J, Gladue I, Kozak J, Leslie M, Chue P, Greenshaw AJ. Randomized controlled pilot trial of supportive text messaging for alcohol use disorder patients. J Subst Abuse Treat 2018; 94:74-80. [PMID: 30243421 DOI: 10.1016/j.jsat.2018.08.014] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 08/09/2018] [Accepted: 08/31/2018] [Indexed: 11/16/2022]
Abstract
AIMS To evaluate the effectiveness of an addiction-related supportive text messaging mobile intervention to improve treatment outcomes for patients with alcohol use disorder (AUD). METHODS A single-rater-blinded randomized trial was conducted involving 59 AUD patients who completed a residential addiction treatment program. Patients in the intervention group (n = 29) received supportive text messages for three months following discharge. Patients in the control group (n = 30) received a text message thanking them for participating in the study. The primary outcome of this study was the three months Cumulative Abstinence Duration (CAD); secondary outcomes (units of alcohol per drinking day, numbers of days to first drink) and exploratory outcomes (health utilization) were evaluated. Subgroup analyses were also done. The enrollment rate in the study was 84%, and of those who enrolled, 73% were retained. RESULTS When primary and secondary outcome measures were examined via effect size analysis, the number of days to first drink was longer in the intervention than control group (large effect size, although not statistically significant). The intervention group's mean first day to drink was over twice the length of the control group (e.g., approximately 60 vs. 26 days, respectively, with a mean difference of 34.97 and 95% CI of -5.87-75.81). Small to moderate effects were found for CAD and units of alcohol per drinking day. Small to negligible effects were found for health utilization. On subgroup analyses, the participants who received text messages, among those who did not attend follow-up outpatient counselling, showed a longer CAD. CONCLUSIONS The results suggest text messaging is a feasible and effective opportunity for follow-up care in patients discharged from residential AUD treatment.
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Urichuk L, Hrabok M, Hay K, Spurvey P, Sosdjan D, Knox M, Fu A, Surood S, Brown R, Coulombe J, Kelland J, Rittenbach K, Snaterse M, Abba-Aji A, Li XM, Chue P, Greenshaw AJ, Agyapong VIO. Enhancing peer support experience for patients discharged from acute psychiatric care: protocol for a randomised controlled pilot trial. BMJ Open 2018; 8:e022433. [PMID: 30121611 PMCID: PMC6104746 DOI: 10.1136/bmjopen-2018-022433] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
INTRODUCTION This study will evaluate the effectiveness of an innovative peer support programme. The programme incorporates leadership training, mentorship, recognition and reward systems for peer support workers, and supportive/reminder text messaging for patients discharged from acute (hospital) care. We hypothesise that patients enrolled in the peer support system plus daily supportive/reminder text messages condition will achieve superior outcomes in comparison to other groups. METHODS AND ANALYSIS This is a prospective, rater-blinded, four-arm randomised controlled trial. 180 patients discharged from acute psychiatric care in Edmonton, Alberta, Canada will be randomised to one of four conditions: (1) enrolment in a peer support system; (2) enrolment in a peer support system plus automated daily supportive/reminder text messages; (3) enrolment in automated daily supportive/reminder text messages alone; or (4) treatment as usual follow-up care. Patients in each group will complete evaluation measures (eg, recovery, general symptomatology and functional outcomes) at baseline, 6 months and 12months. Patient service utilisation data and clinician-rated measures will also be used to gauge patient progress. Patient data will be analysed with descriptive statistics, repeated measures and correlational analyses. The peer support worker experience will be captured using qualitative methods. ETHICS AND DISSEMINATION The study will be conducted in accordance with the Declaration of Helsinki (Hong Kong Amendment) and Good Clinical Practice (Canadian Guidelines). The study has received ethical clearance from the Health Ethics Research Board of the University of Alberta (Ref # Pro00078427) and operational approval from our regional health authority (AHS- (PRJ) #35293). All participants will provide informed consent prior to study inclusion. The results will be disseminated at several levels, including patients/peer supports, practitioners, academics/researchers, and healthcare organisations. TRIAL REGISTRATION NUMBER NCT03404882; Pre-results.
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Agyapong VIO, Hrabok M, Juhas M, Omeje J, Denga E, Nwaka B, Akinjise I, Corbett SE, Moosavi S, Brown M, Chue P, Greenshaw AJ, Li XM. Prevalence Rates and Predictors of Generalized Anxiety Disorder Symptoms in Residents of Fort McMurray Six Months After a Wildfire. Front Psychiatry 2018; 9:345. [PMID: 30108527 PMCID: PMC6079280 DOI: 10.3389/fpsyt.2018.00345] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 07/09/2018] [Indexed: 01/02/2023] Open
Abstract
The Fort McMurray wildfire was the costliest disaster in Canadian history, with far-reaching impacts. The purpose of this paper is to examine the prevalence and risk factors of elevated generalized anxiety disorder (GAD) symptomatology in residents of Fort McMurray 6 months after the wildfire. Data were collected via random selection procedures from 486 participants. Generalized anxiety disorder symptoms were measured via the GAD-7. The 1-month prevalence rate for GAD symptomatology 6 months after the disaster was 19.8% overall, regression analyses revealed six variables with significant unique contributions to prediction of GAD symptomatology. Significant predictors were: pre-existing anxiety disorder, witnessing of homes being destroyed by the wildfire, living in a different home after the wildfire, receiving limited governmental support or limited family support, and receiving counseling after the wildfire. Participants with these risk factors were between two to nearly seven times more likely to present with GAD symptomatology. In addition, participants who presented with elevated symptomatology were more likely to increase use or problematically use substances post-disaster. This study extends the literature on mental health conditions and risk factors following disasters, specifically in the area of generalized anxiety. Findings and implications are discussed.
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Li P, Yang X, Greenshaw AJ, Li S, Luo J, Han H, Liu J, Zhong Z, Guo Z, Xiong H, Yao S, Chen Y, Sun J, Li Z. The effects of cognitive behavioral therapy on resting-state functional brain network in drug-naive patients with obsessive-compulsive disorder. Brain Behav 2018; 8:e00963. [PMID: 29761016 PMCID: PMC5943755 DOI: 10.1002/brb3.963] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 02/08/2018] [Accepted: 02/25/2018] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES Although cognitive behavioral therapy (CBT) is an effective treatment for obsessive-compulsive disorder (OCD), the treatment mechanisms remain poorly understood. This study aimed to investigate the effects of CBT on changes in the intrinsic whole-brain functional network of OCD patients. MATERIALS AND METHODS Twenty drug-naive and noncomorbid OCD patients were recruited, and resting-state functional magnetic resonance imaging was performed before and after 12 weeks of CBT. Moreover, 20 healthy controls were scanned twice with a 12-week interval. A graph-theory degree centrality (DC) approach and functional connectivity method were used to analyze the whole-brain functional network hub and connectivity changes in OCD patients before and after CBT treatment. RESULTS A significant group × time interaction on DC was found in the left dorsolateral prefrontal cortex (DLPFC); the DC in the left DLPFC was significantly reduced after CBT treatment. Resting-state functional connectivity (RSFC) between the left DLPFC and right orbitofrontal cortex was increased in the OCD patients at baseline, and normalized after CBT treatment. RSFC changes between the left DLPFC and default mode network (DMN) positively correlated with changes in clinical symptoms in OCD patients. CONCLUSIONS These findings suggest that CBT can modulate changes in intrinsic functional network hubs in the cortico-striato-thalamo-cortical circuit in OCD patients. Cognitive control network and DMN connectivity may be a potential imaging biomarker for evaluating CBT treatment for OCD.
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Liang S, Brown MRG, Deng W, Wang Q, Ma X, Li M, Hu X, Juhas M, Li X, Greiner R, Greenshaw AJ, Li T. Convergence and divergence of neurocognitive patterns in schizophrenia and depression. Schizophr Res 2018; 192:327-334. [PMID: 28651909 DOI: 10.1016/j.schres.2017.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 05/28/2017] [Accepted: 06/03/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND Neurocognitive impairments are frequently observed in schizophrenia and major depressive disorder (MDD). However, it remains unclear whether reported neurocognitive abnormalities could objectively identify an individual as having schizophrenia or MDD. METHODS The current study included 220 first-episode patients with schizophrenia, 110 patients with MDD and 240 demographically matched healthy controls (HC). All participants performed the short version of the Wechsler Adult Intelligence Scale-Revised in China; the immediate and delayed logical memory of the Wechsler Memory Scale-Revised in China; and seven tests from the computerized Cambridge Neurocognitive Test Automated Battery to evaluate neurocognitive performance. The three-class AdaBoost tree-based ensemble algorithm was employed to identify neurocognitive endophenotypes that may distinguish between subjects in the categories of schizophrenia, depression and HC. Hierarchical cluster analysis was applied to further explore the neurocognitive patterns in each group. RESULTS The AdaBoost algorithm identified individual's diagnostic class with an average accuracy of 77.73% (80.81% for schizophrenia, 53.49% for depression and 86.21% for HC). The average area under ROC curve was 0.92 (0.96 in schizophrenia, 0.86 in depression and 0.92 in HC). Hierarchical cluster analysis revealed for MDD and schizophrenia, convergent altered neurocognition patterns related to shifting, sustained attention, planning, working memory and visual memory. Divergent neurocognition patterns for MDD and schizophrenia related to motor speed, general intelligence, perceptual sensitivity and reversal learning were identified. CONCLUSIONS Neurocognitive abnormalities could predict whether the individual has schizophrenia, depression or neither with relatively high accuracy. Additionally, the neurocognitive features showed promise as endophenotypes for discriminating between schizophrenia and depression.
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Liang S, Vega R, Kong X, Deng W, Wang Q, Ma X, Li M, Hu X, Greenshaw AJ, Greiner R, Li T. Neurocognitive Graphs of First-Episode Schizophrenia and Major Depression Based on Cognitive Features. Neurosci Bull 2017; 34:312-320. [PMID: 29098645 DOI: 10.1007/s12264-017-0190-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 08/18/2017] [Indexed: 02/05/2023] Open
Abstract
Neurocognitive deficits are frequently observed in patients with schizophrenia and major depressive disorder (MDD). The relations between cognitive features may be represented by neurocognitive graphs based on cognitive features, modeled as Gaussian Markov random fields. However, it is unclear whether it is possible to differentiate between phenotypic patterns associated with the differential diagnosis of schizophrenia and depression using this neurocognitive graph approach. In this study, we enrolled 215 first-episode patients with schizophrenia (FES), 125 with MDD, and 237 demographically-matched healthy controls (HCs). The cognitive performance of all participants was evaluated using a battery of neurocognitive tests. The graphical LASSO model was trained with a one-vs-one scenario to learn the conditional independent structure of neurocognitive features of each group. Participants in the holdout dataset were classified into different groups with the highest likelihood. A partial correlation matrix was transformed from the graphical model to further explore the neurocognitive graph for each group. The classification approach identified the diagnostic class for individuals with an average accuracy of 73.41% for FES vs HC, 67.07% for MDD vs HC, and 59.48% for FES vs MDD. Both of the neurocognitive graphs for FES and MDD had more connections and higher node centrality than those for HC. The neurocognitive graph for FES was less sparse and had more connections than that for MDD. Thus, neurocognitive graphs based on cognitive features are promising for describing endophenotypes that may discriminate schizophrenia from depression.
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Agyapong VIO, Juhás M, Ohinmaa A, Omeje J, Mrklas K, Suen VYM, Dursun SM, Greenshaw AJ. Randomized controlled pilot trial of supportive text messages for patients with depression. BMC Psychiatry 2017; 17:286. [PMID: 28768493 PMCID: PMC5541655 DOI: 10.1186/s12888-017-1448-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 07/28/2017] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Depression is projected to be the primary cause of disability worldwide by 2030. In a recent survey, the most commonly cited unmet need among 42.4% of depressed Albertans was the lack of sufficient, accessible, and affordable counselling. Our aim was to test the efficacy of a supportive text messaging mobile health intervention in improving treatment outcomes in depressed patients. METHODS We performed a single-rater-blinded randomized trial involving 73 patients with Major Depressive Disorder. Patients in the intervention group (n = 35) received twice-daily supportive text messages for 3 months while those in the control group (n = 38) received a single text message every fortnight thanking them for participating in the study. The primary outcome of this study was: "Mean changes in the BDI scores from baseline". RESULTS After adjusting for baseline BDI scores, a significant difference remained in the 3 month mean BDI scores between the intervention and control groups: (20.8 (SD = 11.7) vs. 24.9 (SD = 11.5), F (1, 60) = 4.83, p = 0.03, ηp2 = 0.07). The mean difference in the BDI scores change was significant with an effect size (Cohen's d) of 0.67. Furthermore, after adjusting for baseline scores, a significant difference remained in the 3 month mean self-rated VAS scores (EQ-5D-5 L scale) between the intervention and control groups, 65.7 (SD = 15.3) vs. 57.4 (SD = 22.9), F (1, 60) =4.16, p = 0.05, ηp2 = 0.065. The mean difference in change mean self-rated VAS scores was also statistically significant with an effect size (Cohen's d) of 0.51. CONCLUSIONS Our findings suggest that supportive text messages are a potentially useful psychological intervention for depression, especially in underserved populations. Further studies are needed to explore the implications of our findings in larger clinical samples. TRIAL REGISTRATION ClinicalTrials.gov NCT02327858 . Registered 24 December 2014.
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Juhás M, Sun H, Brown MRG, MacKay MB, Mann KF, Sommer WH, Wilman AH, Dursun SM, Greenshaw AJ. Deep grey matter iron accumulation in alcohol use disorder. Neuroimage 2017; 148:115-122. [PMID: 28065850 DOI: 10.1016/j.neuroimage.2017.01.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 12/01/2016] [Accepted: 01/04/2017] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Evaluate brain iron accumulation in alcohol use disorder (AUD) patients compared to controls using quantitative susceptibility mapping (QSM). METHODS QSM was performed retrospectively by using phase images from resting state functional magnetic resonance imaging (fMRI). 20 male AUD patients and 15 matched healthy controls were examined. Susceptibility values were manually traced in deep grey matter regions including caudate nucleus, combined putamen and globus pallidus, combined substantia nigra and red nucleus, dentate nucleus, and a reference white matter region in the internal capsule. Average susceptibility values from each region were compared between the patients and controls. The relationship between age and susceptibility was also explored. RESULTS The AUD group exhibited increased susceptibility in caudate nucleus (+8.5%, p=0.034), combined putamen and globus pallidus (+10.8%, p=0.006), and dentate nucleus (+14.9%, p=0.022). Susceptibility increased with age in two of the four measured regions - combined putamen and globus pallidus (p=0.013) and combined substantia nigra and red nucleus (p=0.041). AUD did not significantly modulate the rate of susceptibility increase with age in our data. CONCLUSION Retrospective QSM computed from standard fMRI datasets provides new opportunities for brain iron studies in psychiatry. Substantially elevated brain iron was found in AUD subjects in the basal ganglia and dentate nucleus. This was the first human AUD brain iron study and the first retrospective clinical fMRI QSM study.
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Huang X, Pu W, Liu H, Li X, Greenshaw AJ, Dursun SM, Xue Z, Liu Z. Altered Brain Functional Connectivity in Betel Quid-Dependent Chewers. Front Psychiatry 2017; 8:239. [PMID: 29209234 PMCID: PMC5701933 DOI: 10.3389/fpsyt.2017.00239] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 11/03/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Betel quid (BQ) is a common psychoactive substance worldwide with particularly high usage in many Asian countries. This study aimed to explore the effect of BQ use on functional connectivity by comparing global functional brain networks and their subset between BQ chewers and healthy controls (HCs). METHODS Resting-state functional magnetic resonance imaging (fMRI) was obtained from 24 betel quid-dependent (BQD) male chewers and 27 healthy male individuals on a 3.0T scanner. We used independent component analysis (ICA) to determine components that represent the brain's functional networks and their spatial aspects of functional connectivity. Two sample t-tests were used to identify the functional connectivity differences in each network between these two groups. RESULTS Seventeen networks were identified by ICA. Nine of them showed connectivity differences between BQD and HCs (two sample t-tests, p < 0.001 uncorrected). We found increased functional connectivity in the orbitofrontal, bilateral frontoparietal, frontotemporal, occipital/parietal, frontotemporal/cerebellum, and temporal/limbic networks, and decreased connectivity in the parietal and medial frontal/anterior cingulate networks in the BQD compared to the HCs. The betel quid dependence scale scores were positively related to the increased functional connectivity in the orbitofrontal (r = 0.39, p = 0.03) while negatively related to the decreased functional connectivity in medial frontal/anterior cingulate networks (r = -0.35, p = 0.02). DISCUSSION Our findings provide further evidence that BQ chewing may lead to brain functional connectivity changes, which may play a key role in the psychological and physiological effects of BQ.
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Huang X, Pu W, Li X, Greenshaw AJ, Dursun SM, Xue Z, Liu H, Liu Z. Decreased Left Putamen and Thalamus Volume Correlates with Delusions in First-Episode Schizophrenia Patients. Front Psychiatry 2017; 8:245. [PMID: 29209237 PMCID: PMC5702009 DOI: 10.3389/fpsyt.2017.00245] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Accepted: 11/06/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Delusional thinking is one of the hallmark symptoms of schizophrenia. However, the underlying neural substrate for delusions in schizophrenia remains unknown. In an attempt to further our understanding of the neural basis of delusions, we explored gray matter deficits and their clinical associations in first-episode schizophrenia patients with and without delusions. METHODS Twenty-four first-episode schizophrenia patients with delusions and 18 without delusions as well as 26 healthy controls (HC) underwent clinical assessment and whole-brain structural imaging which were acquired a 3.0 T scanner. Voxel-based morphometry was used to explore inter-group differences in gray matter volume using analysis of covariance, and Spearman correlation coefficients (rho) between the Scale for the Assessment of Positive Symptoms (SAPS)-delusion scores and mean regional brain volumes was obtained. RESULTS Patients with delusions showed decreased brain gray matter volumes in the left putamen, thalamus, and caudate regions compared with HC. Patients with delusions also showed decreased regional volume in the left putamen and thalamus compared with patients without delusions. SAPS-delusion scores were negatively correlated with the gray matter volumes of the left putamen and thalamus. DISCUSSION Left putamen and thalamus volume loss may be biological correlates of delusions in schizophrenia.
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Agyapong VIO, Mrklas K, Juhás M, Omeje J, Ohinmaa A, Dursun SM, Greenshaw AJ. Cross-sectional survey evaluating Text4Mood: mobile health program to reduce psychological treatment gap in mental healthcare in Alberta through daily supportive text messages. BMC Psychiatry 2016; 16:378. [PMID: 27821096 PMCID: PMC5100254 DOI: 10.1186/s12888-016-1104-2] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 11/01/2016] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND To complement the oversubscribed counselling services in Alberta, the Text4Mood program which delivers daily supportive text messages to subscribers was launched on the 18th of January, 2016. This report presents an evaluation of self-reports of the impact of the program on the mental wellbeing of subscribers. METHODS An online link to a survey questionnaire was created by an expert group and delivered via text messages to mobile phones of all 4111 active subscribers of the Text4Mood program as of April 11, 2016. RESULTS Overall, 894 subscribers answered the survey (overall response rate 21.7 %). The response rate for individual questions varied and is reported alongside the results. Most respondents were female (83 %, n = 668), Caucasian (83 %, n = 679), and diagnosed with a psychiatric disorder (38 %, n = 307), including Depression (25.4 %, n = 227) and Anxiety (20 %, n = 177). Overall, 52 % (n = 461) signed up for Text4Mood to help elevate their mood and 24.5 % (n = 219) signed up to help them worry less. Most respondents felt the text messages made them more hopeful about managing issues in their lives (81.7 %, n = 588), feel in charge of managing depression and anxiety (76.7 %, n = 552), and feel connected to a support system (75.2 %, n = 542). The majority of respondents felt Text4Mood improved their overall mental well-being (83.1 %, n = 598). CONCLUSION Supportive text messages are a feasible and acceptable way of delivering adjunctive psychological interventions to the general public with mental health problems. Given that text messages are affordable, readily available, and can be delivered to thousands of people simultaneously, they present an opportunity to help close the psychological treatment gap for mental health patients in Alberta and elsewhere.
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Chen Y, Meng X, Hu Q, Cui H, Ding Y, Kang L, Juhás M, Greenshaw AJ, Zhao A, Wang Y, Cui G, Li P. Altered resting-state functional organization within the central executive network in obsessive-compulsive disorder. Psychiatry Clin Neurosci 2016; 70:448-456. [PMID: 27377579 DOI: 10.1111/pcn.12419] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 06/19/2016] [Accepted: 06/29/2016] [Indexed: 01/03/2023]
Abstract
AIM Obsessive-compulsive disorder (OCD) is associated with deficits in response inhibition and planning, which are governed by the central executive network. The objective of this study was to investigate both intra- and inter-regional resting-state connectivity within the central executive network in OCD. METHODS Thirty OCD patients and 30 matched healthy controls were scanned using resting-state functional magnetic resonance imaging. The independent component analysis was used on a separate sample of healthy controls to generate the central executive network mask for the subsequent OCD analyses. Regional homogeneity (ReHo) and seed-based functional connectivity analyses were used to explore the differences between intra- and inter-regional synchronized activity within the central executive network in OCD patients at rest. RESULTS Increased ReHo and functional connectivity in the key regions of the central executive network, such as the orbitofrontal cortex, dorsolateral prefrontal cortex, and the angular gyrus, were found in OCD patients. Furthermore, changes in both the ReHo within the orbitofrontal cortex and the functional connectivity between the orbitofrontal cortex and angular gyrus were negatively correlated with OCD duration. CONCLUSION The increased resting-state functional organization within the central executive network may be related to OCD patients' deficits in cognitive control and symptom progression.
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Liang S, Deng W, Wang Q, Ma X, Li M, Brown MRG, Hu X, Li X, Greenshaw AJ, Li T. Performance of Verbal Fluency as an Endophenotype in Patients with Familial versus Sporadic Schizophrenia and Their Parents. Sci Rep 2016; 6:32597. [PMID: 27581658 PMCID: PMC5007652 DOI: 10.1038/srep32597] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 08/08/2016] [Indexed: 02/05/2023] Open
Abstract
What’s the neurocognitive deficit as an endophenotype to familial schizophrenia? Here, we investigate the neurocognitive endophenotype in first-episode patients with familial schizophrenia (FS) and sporadic schizophrenia (SS), and their parents. 98 FS patients and their 105 parents; 190 SS patients and their 207 parents; 195 controls matched with patients, and 190 controls matched with the patients’ parents, were assessed with the short version of the Wechsler Adult Intelligence Scale-Revised in China (WAIS-RC), the immediate and delayed logical memory tests from the Wechsler Memory Scale-Revised in China (WMS-RC), the Verbal Fluency Test (VFT), the Trail Making Test Parts A and B-Modified (TMA, TMB-M), and the Modified Wisconsin Card Sorting Test (WCST-M). The results showed that with age, gender, and education as covariates, after controlling for false discovery rates, the FS group and their parent group performed worse than the SS group and their parent group on VFT. No significant differences were found for other neurocognitive tests between the FS and SS patient groups, and their respective parent groups. Our findings suggest the patients with familial and sporadic schizophrenia and their respective parent groups may have a different genetic predisposition in relation to a cognitive endophenotype.
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94
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Ramasubbu R, Brown MRG, Cortese F, Gaxiola I, Goodyear B, Greenshaw AJ, Dursun SM, Greiner R. Accuracy of automated classification of major depressive disorder as a function of symptom severity. NEUROIMAGE-CLINICAL 2016; 12:320-31. [PMID: 27551669 PMCID: PMC4983635 DOI: 10.1016/j.nicl.2016.07.012] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Revised: 07/07/2016] [Accepted: 07/26/2016] [Indexed: 01/25/2023]
Abstract
Background Growing evidence documents the potential of machine learning for developing brain based diagnostic methods for major depressive disorder (MDD). As symptom severity may influence brain activity, we investigated whether the severity of MDD affected the accuracies of machine learned MDD-vs-Control diagnostic classifiers. Methods Forty-five medication-free patients with DSM-IV defined MDD and 19 healthy controls participated in the study. Based on depression severity as determined by the Hamilton Rating Scale for Depression (HRSD), MDD patients were sorted into three groups: mild to moderate depression (HRSD 14–19), severe depression (HRSD 20–23), and very severe depression (HRSD ≥ 24). We collected functional magnetic resonance imaging (fMRI) data during both resting-state and an emotional-face matching task. Patients in each of the three severity groups were compared against controls in separate analyses, using either the resting-state or task-based fMRI data. We use each of these six datasets with linear support vector machine (SVM) binary classifiers for identifying individuals as patients or controls. Results The resting-state fMRI data showed statistically significant classification accuracy only for the very severe depression group (accuracy 66%, p = 0.012 corrected), while mild to moderate (accuracy 58%, p = 1.0 corrected) and severe depression (accuracy 52%, p = 1.0 corrected) were only at chance. With task-based fMRI data, the automated classifier performed at chance in all three severity groups. Conclusions Binary linear SVM classifiers achieved significant classification of very severe depression with resting-state fMRI, but the contribution of brain measurements may have limited potential in differentiating patients with less severe depression from healthy controls. SVM binary classifiers achieved significant classification of very severe depression with resting state fMRI data. Prefrontal, anterior cingulate and insula were the most discriminative brain regions. No significant classification could be achieved for less severe MDD with resting state data. With emotional task data, SVM classifier performed at chance for all MDD severity groups.
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95
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Chen Y, Juhás M, Greenshaw AJ, Hu Q, Meng X, Cui H, Ding Y, Kang L, Zhang Y, Wang Y, Cui G, Li P. Abnormal resting-state functional connectivity of the left caudate nucleus in obsessive-compulsive disorder. Neurosci Lett 2016; 623:57-62. [PMID: 27143323 DOI: 10.1016/j.neulet.2016.04.030] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/30/2016] [Accepted: 04/13/2016] [Indexed: 11/26/2022]
Abstract
Altered brain activities in the cortico-striato-thalamocortical (CSTC) circuitry are implicated in the pathophysiology of obsessive-compulsive disorder (OCD). However, whether the underlying changes occur only within this circuitry or in large-scale networks is still not thoroughly understood. This study performed voxel-based functional connectivity analysis on resting-state functional magnetic resonance imaging (fMRI) data from thirty OCD patients and thirty healthy controls to investigate whole-brain intrinsic functional connectivity patterns in OCD. Relative to the healthy controls, OCD patients showed decreased functional connectivity within the CSTC circuitry but increased functional connectivity in other brain regions. Furthermore, decreased left caudate nucleus-thalamus connectivity within the CSTC circuitry was positively correlated with the illness duration of OCD. This study provides additional evidence that CSTC circuitry may play an essential role and alteration of large-scale brain networks may be involved in the pathophysiology of OCD.
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Hayes DJ, Northoff G, Greenshaw AJ. Editorial: Reward- and aversion-related processing in the brain: translational evidence for separate and shared circuits. Front Syst Neurosci 2015; 9:147. [PMID: 26578904 PMCID: PMC4625079 DOI: 10.3389/fnsys.2015.00147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 10/12/2015] [Indexed: 11/13/2022] Open
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97
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Brown MRG, Benoit JRA, Juhás M, Dametto E, Tse TT, MacKay M, Sen B, Carroll AM, Hodlevskyy O, Silverstone PH, Dolcos F, Dursun SM, Greenshaw AJ. fMRI investigation of response inhibition, emotion, impulsivity, and clinical high-risk behavior in adolescents. Front Syst Neurosci 2015; 9:124. [PMID: 26483645 PMCID: PMC4586270 DOI: 10.3389/fnsys.2015.00124] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 08/20/2015] [Indexed: 12/27/2022] Open
Abstract
High-risk behavior in adolescents is associated with injury, mental health problems, and poor outcomes in later life. Improved understanding of the neurobiology of high-risk behavior and impulsivity shows promise for informing clinical treatment and prevention as well as policy to better address high-risk behavior. We recruited 21 adolescents (age 14–17) with a wide range of high-risk behavior tendencies, including medically high-risk participants recruited from psychiatric clinics. Risk tendencies were assessed using the Adolescent Risk Behavior Screen (ARBS). ARBS risk scores correlated highly (0.78) with impulsivity scores from the Barratt Impulsivity scale (BIS). Participants underwent 4.7 Tesla functional magnetic resonance imaging (fMRI) while performing an emotional Go/NoGo task. This task presented an aversive or neutral distractor image simultaneously with each Go or NoGo stimulus. Risk behavior and impulsivity tendencies exhibited similar but not identical associations with fMRI activation patterns in prefrontal brain regions. We interpret these results as reflecting differences in response inhibition, emotional stimulus processing, and emotion regulation in relation to participant risk behavior tendencies and impulsivity levels. The results are consistent with high impulsivity playing an important role in determining high risk tendencies in this sample containing clinically high-risk adolescents.
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98
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Brown MRG, Benoit JRA, Juhás M, Lebel RM, MacKay M, Dametto E, Silverstone PH, Dolcos F, Dursun SM, Greenshaw AJ. Neural correlates of high-risk behavior tendencies and impulsivity in an emotional Go/NoGo fMRI task. Front Syst Neurosci 2015; 9:24. [PMID: 25805975 PMCID: PMC4354310 DOI: 10.3389/fnsys.2015.00024] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 02/12/2015] [Indexed: 11/13/2022] Open
Abstract
Improved neuroscientific understanding of high-risk behaviors such as alcohol binging, drug use, and unsafe sex will lead to therapeutic advances for high-risk groups. High-risk behavior often occurs in an emotionally-charged context, and behavioral inhibition and emotion regulation play important roles in risk-related decision making. High impulsivity is an important potential contributor to high-risk behavior tendencies. We explored the relationships between high-risk behavior tendencies, impulsivity, and fMRI brain activations in an emotional Go/NoGo task. This task presented emotional distractor pictures (aversive vs. neutral) simultaneously with Go/NoGo stimuli (square vs. circle) that required a button press or withholding of the press, respectively. Participants' risk behavior tendencies were assessed with the Cognitive Appraisal of Risky Events (CARE) scale. The Barratt Impulsivity Scale 11 (BIS) was used to assess participant impulsivity. Individuals with higher CARE risk scores exhibited reduced activation related to response inhibition (NoGo-Go) in right orbital frontal cortex (OFC) and ventromedial prefrontal cortex. These regions did not show a significant relationship with impulsivity scores. Conversely, more impulsive individuals showed reduced emotion-related activity (aversive-neutral distractors) in dorsomedial prefrontal cortex, perigenual anterior cingulate cortex, and right posterior OFC. There were distinct neural correlates of high-risk behavior tendency and impulsivity in terms of brain activity in the emotional Go/NoGo task. This dissociation supports the conception of high-risk behavior tendency as a distinct construct from that of impulsivity. Our results suggest that treatment for high-risk behavior may be more effective with a nuanced approach that does not conflate high impulsivity necessarily with high-risk behavior tendencies.
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Brown MRG, Sidhu GS, Greiner R, Asgarian N, Bastani M, Silverstone PH, Greenshaw AJ, Dursun SM. ADHD-200 Global Competition: diagnosing ADHD using personal characteristic data can outperform resting state fMRI measurements. Front Syst Neurosci 2012; 6:69. [PMID: 23060754 PMCID: PMC3460316 DOI: 10.3389/fnsys.2012.00069] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Accepted: 09/08/2012] [Indexed: 11/13/2022] Open
Abstract
Neuroimaging-based diagnostics could potentially assist clinicians to make more accurate diagnoses resulting in faster, more effective treatment. We participated in the 2011 ADHD-200 Global Competition which involved analyzing a large dataset of 973 participants including Attention deficit hyperactivity disorder (ADHD) patients and healthy controls. Each participant's data included a resting state functional magnetic resonance imaging (fMRI) scan as well as personal characteristic and diagnostic data. The goal was to learn a machine learning classifier that used a participant's resting state fMRI scan to diagnose (classify) that individual into one of three categories: healthy control, ADHD combined (ADHD-C) type, or ADHD inattentive (ADHD-I) type. We used participants' personal characteristic data (site of data collection, age, gender, handedness, performance IQ, verbal IQ, and full scale IQ), without any fMRI data, as input to a logistic classifier to generate diagnostic predictions. Surprisingly, this approach achieved the highest diagnostic accuracy (62.52%) as well as the highest score (124 of 195) of any of the 21 teams participating in the competition. These results demonstrate the importance of accounting for differences in age, gender, and other personal characteristics in imaging diagnostics research. We discuss further implications of these results for fMRI-based diagnosis as well as fMRI-based clinical research. We also document our tests with a variety of imaging-based diagnostic methods, none of which performed as well as the logistic classifier using only personal characteristic data.
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100
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Hayes DJ, Hoang J, Greenshaw AJ. The role of nucleus accumbens shell GABA receptors on ventral tegmental area intracranial self-stimulation and a potential role for the 5-HT(2C) receptor. J Psychopharmacol 2011; 25:1661-75. [PMID: 21169393 DOI: 10.1177/0269881110389212] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Brain γ-aminobutyric acid (GABA) and 5-hydroxytryptamine (5-HT)(2C) receptors are implicated in the neuronal regulation of reward- and aversion-related behaviour. Within the mesocorticolimbic pathways of the brain, relationships between GABA containing neurons and 5-HT(2C) receptor activity may be important in this context. The primary aim of this study was to investigate the role of NAc shell GABA receptors on ventral tegmental area intracranial self-stimulation (ICSS) and to examine the systemic effects of GABAergic ligands in this context. The second aim was to investigate the relationship between GABA receptor- and 5-HT(2C) receptor-related ICSS behaviour, using systemic administration of the selective agonist WAY 161503. Locomotor activity was assessed to compare the potential motor effects of drugs; feeding behaviour and intra-NAc injections of amphetamine (1.0 µg/side) were used as positive controls. When administered systemically the GABA(A) receptor agonist muscimol and antagonist picrotoxin did not selectively change ICSS reward thresholds, although the 5-HT(2C) receptor agonist WAY 161503 (1.0 mg/kg) decreased reward measures. Intra-NAc shell administration of muscimol (225 ng/side) and picrotoxin (125 ng/side), respectively, decreased and increased measures of reward. Intra-NAc shell baclofen (0-225 ng/side; GABA(B) receptor agonist) did not affect any ICSS measures although it increased feeding. Combining picrotoxin and WAY 161503 attenuated the effects of each. These results suggest that a 5-HT(2C) and GABA(A) receptor-mediated neuronal relationship in the NAc shell may be relevant for the regulation of brain reward pathways.
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