Major Depressive Disorder
Conditions
Keywords
tDCS, neuromodulation, depression, cognition
Brief summary
Background: transcranial direct current stimulation (tDCS) is an innovative treatment for major depression. However, its mechanisms of action are still unclear. Major depression is characterized by impaired processing of emotional information, which returns back to normal after successful antidepressant treatment. In this randomized double-blind study, the investigators aim to assess the effect of tDCS on emotional processing in major depression.
Detailed description
Methods: 40 subjects with major depression (20 active treatment and 20 placebo) will receive ten 30-minutes sessions of active two milliamps or sham tDCS (anode over left dorsolateral prefrontal cortex and cathode over right dorsolateral prefrontal cortex), twice a day for 5 consecutive days. Psychometric assessment of depression (MADRS,Beck Depression Inventory , CGI) and a neuropsychological assessment will be conducted before and after the treatment. A facial emotion recognition task and an attentional emotional task with measurement of eye-tracking, heart rate, respiratory frequency and skin conductance will be conducted before and after the first session, and after the last session. The investigators hypothesize that active tDCS will improve emotional processing in major depression, and that this will be observed after 1 and 10 sessions of tDCS. Conclusions: Studying the impact of transcranial direct current stimulation on emotional processing in major depression could allow to better understand its antidepressant mechanisms
Interventions
DEVICEtranscranial direct current stimulation
Subjects will receive 10 30-minutes sessions of two milliamps transcranial direct current stimulation , twice a day for 5 consecutive day. Facial emotion recognition task and attentional task with measurement of eye-tracking, heartrate, respiratory frequency and skin conductance will be conducted before and after the first session, and after the last session.
Sponsors
Hôpital le Vinatier
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy controls: * Age between 18 and 65 years * Given consent. Depressed subjects: * Major depressive episode (no psychotic features) according to Diagnostic ans Statistical of Mental Disorders number 5 (DSM 5.0.) * Age from 18-65 * Antidepressant stable for the last 4 weeks * MADRS ≥ 20. * Given consent
Exclusion criteria
Healthy controls: * Psychiatric disorder * Addiction except for tobacco addiction * Ocular disease (except from refraction disorders), neurologic or cardiac disease. * Neuroleptic or anticonvulsivant treatment * Presence of a specific contraindication for tDCS (e.g., personal history of epilepsy, metallic head implant, cardiac pacemaker) Depressed subjects: * Other psychiatric disorder except for personality disorders * Ocular disease (except from refraction disorders), neurologic or cardiac disease. * Neuroleptic or anticonvulsivant treatment * Presence of a specific contraindication for tDCS (e.g., personal history of epilepsy, metallic head implant, cardiac pacemaker)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of correct responses at a facial expression recognition task | within 5 days after stimulation | A computerized facial expression recognition task was designed for the study. 240 pictures of emotional faces (8 identities, expressing anger, sadness, happiness, surprise, disgust, or fear, morphed with intensity of 20, 40, 50, 60 and 80%) are randomly displayed on a screen for 500ms. Subjects are asked to identify the emotion by answering on a keyboard. Rate of correct responses is the main outcome. During this task, eye movements are recorded by an eye-tracking device. Skin conductance, respiratory and heart rate frequency are also recorded |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Performance on an attentional dot-probe task | within 5 days after stimulation | Computerized dot-probe attentional task designed for the study. Pairs of emotional faces (neutral/sad ou neutral/happy) are randomly presented on a screen for 1000ms. Then, a probe is presented during 1100ms.subjects are asked to indicate a which side the probe approved During this task, eye movements are recorded by an eye-tracking device. Total time spent on Region of Interest (sad, happy or neutral face) is measured. Skin conductance, respiratory and heart rate frequency are also recorded. |
| tests of executive functions | an average of two weeks | Neuropsychological assessment : attentional functioning (TAP), executive functioning (BADS, working memory, go/no-go, stroop), memory (california verbal learning test) Improvement of executive functioning by tDCS will be assessed. |
| Beck depression inventory scale | within 5 days after stimulation | — |
| Clinical global impression scale | an average of two weeks | — |
| Evolution of the depressive symptoms measured by MADRS | an average of two weeks | Montgomery-Asberg Depression Rating Scale is a 10-item scale to evaluate the intensity of the depressive symptoms. |
| Skin conductance measured in speed per microseconds | within 5 days after stimulation | Recorded with physiologic data system (BIOPAC) |
| Heart rate measured in number of heart pulses per milliseconds | within 5 days after stimulation | Recorded with physiologic data system (BIOPAC) |
| Respiratory frequency measured in number of respiratory cycles per minute | within 5 days after stimulation | Recorded with physiologic data system(BIOPAC) |
| Eye movements during facial emotion recognition task and attentional task | within 5 days after stimulation | Recorded by Eye tracker.Measurement of total time spent on specific Region of interest (eyes, nose, mouth, emotional face) |
Countries
France
Outcome results
None listed