The purpose of this study is to determine if daily practice of mental imagery improves psychological variables such as motivation, behavioral activation, depression, mood, optimism, anhedonia, and psychological well-being, and if it's combination with activity planning is more effective than activity planning alone. This study will analyze the effect of 2 mental imagery conditions (planned activity imagery, best possible self) and a control condition of activity planning alone, administered to a general population over a 2-week period.~Our hypotheses are an improvement for both experimental conditions (planned activities imagery and best possible self imagery) of mood, behavioral activation, depressive symptomatology, optimism, psychological well-being, cognitive and behavioral avoidance, and anhedonia, compared to the control condition. Several studies have been able to show the effect of either imagery condition on certain variables (notably behavioral activation and mood for the planned activity imagery as well as optimism and mood for the best possible self), but the interest of our study is to assess the effect of each of the proposed protocols on a broader range of variables. This will allow us to determine the specific effect of each protocol as well as to compare their effectiveness.~In this study we will recruit 120 participants, randomly assigned to one of three conditions: (1) mental imagery of planned activities, (2) mental imagery of best possible self, (3) planned activity control group. All participants will be asked to complete a series of standardized assessments in 4 steps (at the first meeting, at the second meeting 15 days later, and a follow-up at 1 and 3 months post-intervention). The questionnaires will assess depression, behavioral activation, mood, optimism, imagery skills, anhedonia, and psychological well-being.~In each group, participants will have to think about 4 activities to be implemented within the next two weeks, and answer about 10 questions about the chosen activities (rated from 0 to 10 on a visual analogical scale). These questions evaluate, among other things, the motivation, the anticipated effort, the anticipated pleasure, and the degree of avoidance related to each activity using a visual analog scale. This questionnaire will be completed at the first meeting and also after the completion of each activity, at home. The protocol is identical for each condition except for the content of the imagery exercise or no imagery exercise for the control condition. The participants in the experimental conditions will be instructed to repeat the 5-minute imagery exercise at home every day for 2 weeks and report in a booklet everyday their rating of the imagery exercise (vividness, difficulty and their mood after the exercise).~At a second meeting 2 weeks later, all participants will be asked to complete the standardized assessments again and report whether or not the planned activities were completed, as well as conduct a semi-structured interview about their experience, the feasibility and difficulty of the task. Participants will then receive a follow-up survey by e-mail at 1 and 3 months post-intervention, in which they will again be asked to complete the selected standardized questionnaires. The booklets in which they reported the questionnaires about their planned activities (all conditions) and the ratings of imagery exercise (for experimental conditions) will be brought back on that meeting.
This study aims to investigate the effects of mental imagery practice on depression, behavioral activation, psychological well-being and other processes involved in depression such as anhedonia.~We use a multiple baseline design in addition to a pre-post and follow-up standardized assessment design.