gene-person-environment interaction in resilience against depression

Depression research focuses almost exclusively on negative mood, with little
attention to positive mood. This calls for remediation because i) positive
affect (PA) and negative affect (NA) are not two extremes within a
unidimensional construct, but relatively independent; and ii) positive emotions
are likely protective since they broaden the attentional focus, thus
facilitating the use of positive factors, or natural rewards, in the flow of
daily life.
In a recent twin study using novel momentary assessment methodology, I showed
that PA not only reduced the risk of developing negative mood states in
response to minor daily life stressors (a trait I identified as an indicator of
genetic risk for depression), but also attenuated expression of genetic risk
for depression.
PA thus mitigates symptoms of, and expression of genetic risk for, depression.

My research proposal, therefore, will focus on the changeability (plasticity)
of the ability to experience positive emotions in response to daily events
(natural rewards), as a first step towards novel (preventive) interventions.
The main question is: can the ability to experience reward in daily life be
experimentally modified? Additional questions are: how does experimental
modification of reward impact on depressive symptomatology, can individual
variation be traced to genetic variation, and how do increases in reward
experience relate to risk of future relapse in depression?

Experience Sampling Method (ESM) is a structured diary, momentary assessment
technique to study subjects in their daily life. Subjects are randomised to two
groups. At baseline, all subjects will undergo a six-day period of ESM. Then,
one group receives mindfulness-based cognitive therapy (MBCT) (8 weekly
sessions of two hours including daily homework exercises) by an experienced
MBCT therapist, and the other group care as usual, followed by a second six-day
ESM assessment. Follow-ups will take place 6 and 12 months after participants
ended their MBCT training. Any additional treatment, if applicable, will be
kept constant within subjects. Subjects will be globally informed, but remain
blind as to how ESM measures relate to testing the hypothesis.

The experimental group receives 8 weeks of mindfulness training by an
experienced trainer in addition to their normal treatment, if any. Sessions are
weekly (2,5 hours a session) and subjects receive daily homework exercises. The
control group continues their normal treatment, if any.

The main burden for the subjects is participating in the ESM procedure, where
they have to fill in a dairy concerning daily life experiences and mood states
at 10 random moments during the day (not during the night) for 6 consecutive
days. These ESM measurements are performed two times: before and after the
intervention. The advantage is that the subjects fill in these diaries during
their daily lifes and do not need to come to the lab for this.
At five moments they have to come to the lab for short periods:
The screening (110 min)
Briefing ESM first period (15 min)
Baseline depression questionnaires and debriefing ESM (1 hour)
Briefing ESM second period (15 min)
After 8 weeks: depression questionnaires and debriefing ESM (50 minutes)
Participants will have to come to additional follow-up meetings 6 and 12 months
after the MBCT training (30 minutes each).
Also at baseline some saliva will be taken from the subjects for DNA
measurements.


There are no health risks associated with the research.
There is a personal benefit for subjects in that they are offered a free
mindfulness training that is expected to improve their resilience against
depression.
There is a scientific benefit in that it leads to greater insight into the
biological and psychological factors related to resilience, which will be
important for the prevention of depressive disorders in the population.