Active clinical trials for "Depressive Disorder, Major"

The purpose of this study is to use positron emission tomography (PET) imaging to measure the activity of the kappa opioid receptor (KOR) in the brains of depressed and non-depressed individuals.

This study examines whether depression in people with borderline personality disorder is different than depression in people without borderline personality disorder. Unlike people who have depression alone (i.e. without borderline personality disorder), people with borderline personality disorder have depressions that often do not improve with medications. This makes treating depression much more challenging in someone with borderline personality disorder than without borderline personality disorder. Borderline personality disorderis associated with difficulty in understanding and communicating feelings. Impaired emotion processing may reflect dysfunction of an area of the brain, the anterior cingulate. Depression is associated with changes in anterior cingulate activity. The investigators believe that when borderline personality disorder is present with depression, brain activity changes in the anterior cingulate will not be the same as in depressed patients without borderline personality disorder. An electroencephalogram records brain electrical activity. In this study, the investigators will measure electroencephalogram indices reflecting anterior cingulate activity. HYPOTHESIS: In this study, the investigators predict that when borderline personality is present with depression, electroencephalogram indices of anterior cingulate activity will be different from when depression is present alone (without borderline personality). This could help to explain why people with borderline personality have depressions that are harder to treat than depressions in people without borderline personality. The investigators also predict that electroencephalogram indices of the anterior cingulate will reflect emotional processing ability, as measured by validated questionnaires.

This is a Phase 2 double-blind, long-term observational follow-up study of participants from Study PSIL201. Participants providing informed consent will be enrolled into this study and will complete web surveys and telephone interviews conducted by one central site at the following time intervals: months 2, 3, 4, 5 and 6 (± 7 days for each assessment) and months 8, 10, 12, 14, 16, 18, 20, 22 and 24 (± 14 days for each assessment).

Several lines of evidence support the existence of an underlying abnormality in brain energy metabolism may play a key role in the biology of mood disorders. The current study utilizes two distinct but complementary imaging techniques, fluorodeoxyglucose (FDG) positron emission tomography (PET) and multinuclear magnetic resonance spectroscopy (MRS), to better understand the nature of these metabolic abnormalities in major depressive disorder (MDD). The investigators hypothesize that individuals with depression will have increased metabolic activity as measured by PET in certain brain regions involved in mood regulation, but that this metabolic activity will be inefficient based on MRS findings. For this study, the investigators will study 10 medication-free, currently depressed participants with recurrent MDD, 10 depressed participants with recurrent MDD currently taking antidepressant medication, and up to 20 healthy control participants matched to depressed participants for age and gender. Depressed and healthy participants will each undergo one PET scan and one MRS scanning session.

The main objective of this study is to confirm the existence of risky decision making in a non strategic situation (Iowa Gambling Task) and a deficit of decision making in social situations, linked to greater sensitivity to injustice (Ultimatum Game) and a lower level of trust (Trust Game) in elderly depressed patients with a history of suicide attempts in comparison with older depressed patients without a history of suicidal acts and healthy subjects.

The investigators are doing this study to find out if they can use electroencephalographic (EEG) recordings, which measure brain waves, to predict response to antidepressant treatments, as well as to distinguish patients who have depression from those who do not. In particular the investigators want to test the usefulness of a new type of analysis of EEG recordings called brain network activation or BNA. BNA allows to identify patterns of activation in brain networks and to track their changes over time.

Acquiring, processing and utilising "information" is crucial to any mental function -including seemingly simple daily functions. Collectively called 'cognitive functions', these processes are a result of different regions of the brain acting together. Disruption of these cognitive functions increases the risk of development of mental health problem. Recently it has been proposed that inflammatory pathways may contribute to disorders of cognition and behaviour like depression. This is largely due to research showing that those with inflammatory conditions like arthritis are more likely to develop mental health problems like depression. Conversely, those who suffer from mental health problems (even in the absence of inflammatory conditions) have large amounts of inflammatory molecules in the blood. Studies in animals suggest that inflammation outside the brain can reach and affect the brain in a number of ways. So, does inflammation play a role in the development of cognitive and behavioural symptoms? What are the pathways involved? The current project tries to address this question. Specifically, the investigators intend to use modern scanning techniques to examine the effect of inducing a low grade inflammation (using a commonly used typhoid vaccine) to see how the inflammation affects how different regions of the act together to perform cognitive functions.

Major depressive disorder (MDD) is one of the most common psychiatric disorders, with high recurrence rate, suicide rate and disability rate. It's reported that the global burden caused by MDD will be up to the second rank among all the disease burdens by 2020. China is also confronted with the daunting challenges against MDD. It's assessed that the monthly incidence of MDD is 6.1%, non-hospitalizing rate reaches up to 92% and the non-treatment rate is approximate 95%. However, to date, the pathogenesis of MDD is obscure and the current therapies don't work well. Therefore, it's urgent and critical to elucidate the pathogenesis of MDD, to develop early diagnostic criteria and effective intervention in MDD. Considering the diversity of weights on genetic factor and environmental factor in MDD, in this project, the investigators aim firstly to explore the effect of "genetic-environmental interaction"on the pathogeny of MDD for classifying MDD into "genetic type", "environmental type" and "others" based on a case-control study. We next conduct the neurobiological, neurocognitive and psycho-behavioral assessments among MDD, schizophrenia and healthy groups to screen the salient endophenotypes for establishing the diagnostic models of MDD . The investigators further analyse the changes of these indicators after 8 weeks'medication to select the potential predictors for therapeutic evaluations and interventional options in MDD patients. Finally, the investigators continue a 2-year follow-up study to test and verify the predictors of prognosis in MDD patients.

Deficient cognitive control (CC) and the use of dysfunctional emotion regulation strategies (ERS) are both central characteristics of major depression. Both are associated with reduced activity of the dorsolateral prefrontal cortex (dlPFC). Transcranial direct current stimulation (tDCS) is a safe, simple and effective non-invasive method to modulate the cortical excitability. The goal of this randomized, sham-controlled, double blind clinical trial is to examine the effect of transcranial direct current stimulation (tDCS) on the CC and ERS in depressed patients compared to healthy subjects. Overall, the study will include 44 participants (22 depressed Patients and 22 healthy subjects). Each participant will complete a CC task while receiving sham tDCS in one session and anodal tDCS in the other session (counterbalanced). Afterwards the ERS 'rumination' will be measured during a resting phase by means of a questionnaire and psychophysiological measures (heart rate variability). The investigators hypothesize (a) an amelioration of CC by anodal tDCS and (b) a reduced use of the dysfunctional emotion regulation strategy 'rumination' after anodal tDCS. Overall this experiment will provide new and reliable data for the development of new treatment methods.

The aim of this study is to identify genetic, physical (brain) and psychological (cognitive) markers (or combinations of them) that predict specific response to a range of antidepressants treatment (Escitalopram, Venlafaxine, Sertraline) in patients diagnosed with major depressive disorder. This study is focused on outcomes which may impact on how "personalised medicine" is implemented in depression.