Examining Cognitive Mechanisms of Clinical Improvement Following Mindfulness Based Therapy for Depressed Individuals

Study Overview
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Brief Summary
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Depression one of the leading causes of disability worldwide. Individuals suffering from depression typically exhibit impairments in various mental abilities, such as the ability to effectively direct and control attention and the ability to switch between thinking about different things and concepts (commonly referred to as cognitive flexibility). Mindfulness meditation training is a technique which involves focusing one's awareness on the present moment, while calmly acknowledging and accepting one's feelings, thoughts, and bodily sensations. It has been well documented to improve depressive symptoms and prevent recurrence of depressive episodes, yet little is known about how mindfulness does so and what are the underlying mental mechanisms involved. Here the investigators propose to examine the efficacy of an 8-week mindfulness training program in improving the ability to direct and control attention, as well as in cognitive flexibility. Individuals diagnosed with recurrent depression will undergo an 8-week mindfulness training program. Participants' depressive symptoms as well as their performance on measures of attention and cognitive flexibility will be examined. Participants will be assigned to mindfulness training or a wait-list control group. Half of the participants will be examined before and after the mindfulness training program and the other half will be tested 8-weeks apart and then begin their training.

Official Title
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Examining Cognitive Mechanisms of Clinical Improvement Following Mindfulness Based Cognitive Therapy for Depressed Individuals

Conditions
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Depression

Intervention / Treatment
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* Behavioral: Mindfulness Based Cognitive Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Reporting dysphoria for at least two months prior HAM-D score of at least 11 No history of psychiatric disorders of psychotic features, neurological disorders, or substance abuse in the past 6 months Verified age between 18-65 years old Had no suicidal attempts during the past six months No prior experience with MBCT or other systematic meditation programs Exclusion Criteria: History of psychosis, neurological disorder, and substance abuse for the past 6 months Suicide attempt in past 6 months Prior experience with MBCT or other systematic meditation program

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Mindfulness Based Cognitive Therapy (MBCT)<br>This group will receive 8 weeks of Mindfulness Based Cognitive Therapy | Behavioral: Mindfulness Based Cognitive Therapy<br>* 8 weekly meetings in which basic mindfulness and meditation skills are taught, such as breathing meditation, body scan meditation, open awareness meditation, movement meditation, and targeting depression related cognitions and emotions in a mindful manner, as well as awareness exercises, group discussions, and daily home meditation practice routines<br>|
| Active Comparator: Waiting list<br>This group will be tested twice 8-10 weeks apart and then receive 8 weeks of Mindfulness Based Cognitive Therapy | Behavioral: Mindfulness Based Cognitive Therapy<br>* 8 weekly meetings in which basic mindfulness and meditation skills are taught, such as breathing meditation, body scan meditation, open awareness meditation, movement meditation, and targeting depression related cognitions and emotions in a mindful manner, as well as awareness exercises, group discussions, and daily home meditation practice routines<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline in depressive symptoms as measured by the Hamilton Depression Rating Scale |  | Once upon recruitment (baseline), and a second time at 8-10 weeks following the MBCT program | 
| Change from baseline in cognitive flexibility, as measured by a computer task involving task-switching and by the Torrance Test for Creative Thinking |  | Once upon recruitment (baseline), and a second time at 8-10 weeks following the MBCT program | 
| Change from baseline in attention regulation, as measured by the Attention Network Test |  | Once upon recruitment (baseline), and a second time at 8-10 weeks following the MBCT program |