Investigating the Mechanisms of Mindfulness-based Cognitive Therapy (MBCT)

Inclusion Criteria: Participants with remitted depression (rMDD): * At least two previous episodes of DSM-IV major depression in adulthood, diagnosed using the Mini International Neuropsychiatric Interview (M.I.N.I). * Full or partial remission for at least three months with two depressive episodes within the last five years. * A score of less than or equal to 12 on the Montgomery Asberg Depression Rating Scale (MADRS) mood assessment. * If on medication, no recent or planned major changes Healthy volunteers: * In good psychological health screened with the M.I.N.I All participants: * in good physical health (to reduce risk of confounding physical health problems). * sufficiently fluent in English to ensure valid understanding and completion of the tasks. * minimum I.Q level of 80 to ensure sufficient understanding of the neurocognitive tasks administered. * colour vision and acuity within normal/corrected to normal limits. Exclusion criteria: * Any current mental health diagnosis (DSM-IV diagnosis including current major depression, bipolar disorder, psychosis, Obsessive Compulsive Disorder (OCD), substance abuse or dependence, eating disorders) * Physical health or neurological disorders that might interfere with the interpretation of the tasks, including a history of significant head injury. * In addition healthy volunteers will be without a history mental health disorders (DSM-IV) * Current or previous experience of mindfulness-based treatments or extensive cognitive behavioural treatment, or planned participation in psychological treatments during the key time for the study (between pre and post visits). * Planned major alteration in drug treatment for depression between pre and post visits.