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81.
Daniel H. Wolf Theodore D. Satterthwaite Jacob J. Kantrowitz Natalie Katchmar Lillie Vandekar Mark A. Elliott Kosha Ruparel 《Schizophrenia bulletin》2014,40(6):1328-1337
Motivational deficits play a central role in disability caused by schizophrenia and constitute a major unmet therapeutic need. Negative symptoms have previously been linked to hypofunction in ventral striatum (VS), a core component of brain motivation circuitry. However, it remains unclear to what extent this relationship holds for specific negative symptoms such as amotivation, and this question has not been addressed with integrated behavioral, clinical, and imaging measures. Here, 41 individuals with schizophrenia and 37 controls performed a brief, computerized progressive ratio task (PRT) that quantifies effort exerted in pursuit of monetary reward. Clinical amotivation was assessed using the recently validated Clinical Assessment Interview for Negative Symptoms (CAINS). VS function was probed during functional magnetic resonance imaging using a monetary guessing paradigm. We found that individuals with schizophrenia had diminished motivation as measured by the PRT, which significantly and selectively related to clinical amotivation as measured by the CAINS. Critically, lower PRT motivation in schizophrenia was also dimensionally related to VS hypofunction. Our results demonstrate robust dimensional associations between behavioral amotivation, clinical amotivation, and VS hypofunction in schizophrenia. Integrating behavioral measures such as the PRT will facilitate translational efforts to identify biomarkers of amotivation and to assess response to novel therapeutic interventions.Key words: motivation, progressive ratio, ventral striatum, fMRI, negative symptoms 相似文献
82.
Meredith Achey BM Jason L. Aldred MD Noha Aljehani MD Bastiaan R. Bloem MD PhD Kevin M. Biglan MD MPH Piu Chan MD PhD Esther Cubo MD PhD E. Ray Dorsey MD MBA Christopher G. Goetz MD Mark Guttman MD Anhar Hassan MB BCh FRACP Suketu M. Khandhar MD Zoltan Mari MD Meredith Spindler MD Caroline M. Tanner MD PhD Pieter van den Haak MSc Richard Walker MD Jayne R. Wilkinson MD 《Movement disorders》2014,29(7):871-883
Travel distance, growing disability, and uneven distribution of doctors limit access to care for most Parkinson's disease (PD) patients worldwide. Telemedicine, the use of telecommunications technology to deliver care at a distance, can help overcome these barriers. In this report, we describe the past, present, and likely future applications of telemedicine to PD. Historically, telemedicine has relied on expensive equipment to connect single patients to a specialist in pilot programs in wealthy nations. As the cost of video conferencing has plummeted, these efforts have expanded in scale and scope, now reaching larger parts of the world and extending the focus from care to training of remote providers. Policy, especially limited reimbursement, currently hinders the growth and adoption of these new care models. As these policies change and technology advances and spreads, the following will likely develop: integrated care networks that connect patients to a wide range of providers; education programs that support patients and health care providers; and new research applications that include remote monitoring and remote visits. Together, these developments will enable more individuals with PD to connect to care, increase access to expertise for patients and providers, and allow more‐extensive, less‐expensive participation in research. © 2014 International Parkinson and Movement Disorder Society 相似文献
83.
Addictions to licit and illicit drugs are chronic relapsing brain disorders that affect circuits that regulate reward, motivation, memory, and decision-making. Drug-induced pathological changes in these brain regions are associated with characteristic enduring behaviors that continue despite adverse biopsychosocial consequences. Repeated exposure to these substances leads to egocentric behaviors that focus on obtaining the drug by any means and on taking the drug under adverse psychosocial and medical conditions. Addiction also includes craving for the substances and, in some cases, involvement in risky behaviors that can cause death. These patterns of behaviors are associated with specific cognitive disturbances and neuroimaging evidence for brain dysfunctions in a diverse population of drug addicts. Postmortem studies have also revealed significant biochemical and/or structural abnormalities in some addicted individuals. The present review provides a summary of the evidence that has accumulated over the past few years to implicate brain dysfunctions in the varied manifestations of drug addiction. We thus review data on cerebrovascular alterations, brain structural abnormalities, and postmortem studies of patients who abuse cannabis, cocaine, amphetamines, heroin, and “bath salts”. We also discuss potential molecular, biochemical, and cellular bases for the varied clinical presentations of these patients. Elucidation of the biological bases of addiction will help to develop better therapeutic approaches to these patient populations. 相似文献
84.
85.
Mark Viron Iruma Bello Oliver Freudenreich Derri Shtasel 《Community mental health journal》2014,50(5):560-565
Specialized transitional shelters are available in various cities to provide assistance to homeless individuals with serious mental illness. Little is known about the population using such shelters. The authors conducted a retrospective chart review to collect demographic, social, and clinical data of residents in a state-operated mental health transitional shelter in Massachusetts. A total of 74 subjects were included. Schizophrenia-spectrum disorders were present in 67.6 % of the sample and mood disorders in 35.1 %. Substance use disorders were documented in 44.6 %. Chronic medical illness (mostly hypertension, dyslipidemia, asthma, and diabetes) was found in 82.4 %. The co-occurrence of a psychiatric and substance use disorder and chronic medical illness was found in 36.5 %. The majority (75.7 %) of patients had a history of legal charges. Homeless individuals with serious mental illness served by specialized transitional shelters represent a population with complex psychiatric, medical and social needs. 相似文献
86.
Kristin L. Ballard Mark A. Sander Bonnie Klimes-Dougan 《Community mental health journal》2014,50(2):145-149
This study evaluated student outcomes of an expanded school mental health (ESMH) model that placed community mental health clinicians on-site in schools to identify and treat children with mental health needs. The first aim of this study was to consider school-related outcomes (suspension rates and attendance rates) for those students who received ESMH treatment (n = 159) were compared to a matched high-risk sample that did not receive such services (n = 148). Results demonstrated differences between groups over time on measures of suspensions and attendance but not academic achievement. The second aim of this study was to evaluate change in social–emotional functioning (Strengths and Difficulties Questionnaire Scores) over time for the treatment group. Results indicated significant improvements on several parent and teacher ratings. Despite limitations of the ESMH framework examined in this study, the overall results suggest some promising advantages for students who received ESMH services. 相似文献
87.
88.
Psychiatric Quarterly - 相似文献
89.
Jennifer A. Walsh Mark D. Vida M. D. Rutherford 《Journal of autism and developmental disorders》2014,44(5):1018-1026
Rutherford and McIntosh (J Autism Dev Disord 37:187–196, 2007) demonstrated that individuals with autism spectrum disorder (ASD) are more tolerant than controls of exaggerated schematic facial expressions, suggesting that they may use an alternative strategy when processing emotional expressions. The current study was designed to test this finding using photographs of real people. In addition, two control tasks were added to eliminate alternative explanations. We replicated the findings of Rutherford and McIntosh (J Autism Dev Disord 37:187–196, 2007) and also demonstrated that adults with ASD do not show this tolerance when evaluating how realistic the expressions are. These results suggest adults with ASD employ a rule-based strategy to a greater extent than typical adults when processing facial expressions but not when processing other aspects of faces. 相似文献
90.
Mark S. Freedman Nicola De Stefano Frederik Barkhof Chris H. Polman Giancarlo Comi Bernard M. J. Uitdehaag Florence Casset-Semanaz Brian Hennessy Lorenz Lehr Bettina Stubinski Dominic L. Jack Ludwig Kappos 《Journal of neurology》2014,261(3):490-499
The REFLEX study (NCT00404352) established that subcutaneous (sc) interferon (IFN) β-1a reduced the risks of McDonald MS (2005 criteria) and clinically definite multiple sclerosis (CDMS) in patients with a first clinical demyelinating event suggestive of MS. The aim of this subgroup analysis was to assess the treatment effect of sc IFN β-1a in patient subgroups defined by baseline disease and demographic characteristics (age, sex, use of steroids at the first event, classification of first event as mono- or multifocal, presence/absence of gadolinium-enhancing lesions, count of <9 or ≥9 T2 lesions), and by diagnosis of MS using the revised McDonald 2010 MS criteria. Patients were randomized to the serum-free formulation of IFN β-1a, 44 μg sc three times weekly or once weekly, or placebo, for 24 months or until diagnosis of CDMS. Treatment effects of sc IFN β-1a on McDonald 2005 MS and CDMS in the predefined subgroups were similar to effects found in the intent-to-treat population. McDonald 2010 MS was retrospectively diagnosed in 37.7 % of patients at baseline. Both regimens of sc IFN β-1a significantly reduced the risk versus placebo of McDonald 2005 MS and CDMS, irrespective of McDonald 2010 status at baseline (risk reductions between 29 and 51 %). The effect of sc IFN β-1a was not substantially influenced by baseline patient demographic and disease characteristics, or baseline presence/absence of McDonald 2010 MS. 相似文献