The Neurobiological Mechanisms of Resilience to Stress

The association between stress and the development of a psychopathology is an
extensively studied research topic. A specific type of stressor, which has been
known to cause psychopathologies like depression, anxiety disorder and
posttraumatic stress disorder (PTSD), is the traumatic experience. Statistics
show that not every individual that experienced a traumatic event will develop
psychopathology. This study aims to investigate the relationship between neural
functioning, brain structure, hormone response, genetic makeup and heart rate
variability and resilience for stress.

The objective of the study is to examine characteristics in brain function,
structure, hormonal response, genetic makeup and heart rate variability
specific for resilience to stress

This study will use a case-control design with three groups. Participants*
brain volume will be measured using a structural magnetic resonance imaging
(MRI) technique. Resting State brain activation patterns will be measured using
functional MRI (fMRI), which will also be used for measuring event related
brain activation during a social stress task (the MIST), during an emotional
working memory task (the Emotional Sternberg Task) and during an implicit
emotion regulation task. Finally, diffusion tensor imaging (DTI) will be used
to measure structural connectivity. Due to the length of the scanprotocol,
scanning will take place on two different moments. In addition to the
scanprotocol, participants will be asked to complete behavioural, cognitive and
emotion-related questionnaires. Hormonal responses and DNA will be isolated
from saliva samples.

Functional MRI Tasks:
The Montreal Imaging Stress Task (MIST): a series of mental arithmetic
challenges, which will increase in difficulty as performance goes up.
Participants will think they are performing below average. In addition a social
evaluative component is added by negative remarks coming from the investigator.
Emotional Sternberg task: Participants are presented with targets followed by
either an emotional or neutral distracter, followed by a recognition phase in
which they are required to recognize the presented targets.
Implicit emotion regulation: Participants are asked to react to the emotional
expression of shown faces. On top of these faces the names of emotions are
printed. Trials are either congruent or incongruent. Reaction time on each
trial is measured to compose a measure for emotion regulation

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MRI is a fairly safe, non-invasive measuring technique, which involves no
catheterizations or introduction of exogenous tracers. However, there are a few
contraindications for participating in a MRI scan. The MRI scanner is basically
a large magnet in which the individual has to take place; the scanner is shaped
like a small tunnel. When measuring the brains, individuals have to lay head
first in the tunnel, which can cause symptoms of claustrophobia. In these cases
the study will be terminated immediately at the request of the individual.
Other contraindications of participating in the study are pregnancy, the
possession of ferromagnetic foreign bodies in a participants* body, and the
possession of a cardiac pacemaker. Although there is no direct benefit to the
participants, the proposed research is expected to make a significant
contribution to our understanding of the neural mechanisms of resilience to
stress. In the end, this knowledge will prove very useful in the development of
resilience enhancing interventions. Especially individuals that have a high
risk of experiencing severe stressors, due to for instance their occupation,
will benefit a lot from developing more resilience towards stress. To be able
to investigate the differences between resilient and vulnerable individuals we
need participants with psychopathologies. Due to the high comorbidity of
phobias1 with other psychopathologies, the expectancy rate of individuals
experiencing claustrophobia symptoms in the scanner is higher for the patient
groups than it is for the healthy control group or the resilient group. However
the participants all get a panic button and the researchers will abort the
study immediately after this button is pressed in order to keep participants*
discomfort as low as possible. Furthermore, we will exclude subjects with
claustrophobia. Large numbers of patients have already been scanned by our
group for other protocols (i.e., NESDA)