Reward Sensitivity and Stress Vulnerability: A pilot study

Social situations are usually rewarding and pleasant, but can also be exciting
and at times stressful. Sensing positive feedback from others, such as praises
and smiles, helps us enjoy social situations and seek them out. Negative
feedback, such as criticism and frowns, on the other hand, makes us avoid the
company of our peers. Naturally, there are great differences among people in
how much they enjoy the positive social feedback and how much they dislike the
negative one. For example, those who hardly notice being praised, but are very
sensitive to being criticized, become easily anxious and stressed in social
situations. This seems to be the case for many people with mental health
problems, namely psychosis. It is known that people with psychosis tend to have
difficulties coping with social situations and prefer to spend their time
alone. Researchers believe that this may be due to the fact that compared to
healthy individuals, people with psychosis are less pleased by rewarding
feedback and more stressed by the negative one. We set out to investigate the
reasons for this imbalance. First, we would like to learn whether the
sensitivity to positive feedback, such as winning money, goes hand-in-hand with
sensitivity to social feedback, such as positive and negative reactions of
other people. To do this, we would first like to conduct a simple experiment
with healthy individuals that tests their reactions to winning and losing money
and interacting with their peers.

The primary aim of this study is to validate the paradigms designed to
investigate the effects of social stress and reward on in healthy individuals.
This will allow us to evaluate and optimize the experimental paradigms in terms
of their design, duration, salience and capacity to detect valid results, with
the aim of developing the most effective and safe tests to be used in the
future study of stress and reward reactivity in psychosis.
Another objective of the study is to determine the long-term effects of stress
on the thoughts and emotions of the research subjects in the context of their
daily lives. Since mental and emotional states change throughout the course of
the day, we intend to assess them multiple times for the duration of
approximately 1.5 days post-study.
The main aim of this pilot study is thus to maximize the benefits and minimize
the risks of the planned experiment.

The current study has a randomized design with two conditions. Each participant
will be randomly assigned to one, but never both of the conditions. The
participants in the ostracism condition will complete the reward-learning task
followed by the ostracism task. The participants allocated to the social stress
condition will perform an identical reward-learning task, followed by the
social stress task.
Regardless of the condition, the study will consist of a single session lasting
approximately two hours, followed by a 1.5 day period of experience sampling
method. During the study session, all procedures will be explained to the
participants who will then provide their informed consent. Subsequently, all
participants will complete a brief neuropsychological assessment followed by
both experimental paradigms (reward-learning and ostracism, or reward-learning
and social stress), and finally a battery of demographic, lifestyle and
personality questionnaires. Eight brief questionnaires and cortisol samples
will be collected throughout the study session to test for subjective and
objective markers of stress, positive and negative affect. The entire study
session will take place at the Maastricht University, Faculty of Psychology and
Neuroscience. Following successful study completion, all participants will
obtain a PsyMate® and instructions on how to use it. They will be asked carry
it around for the rest of the day and throughout the next day. At the end of
the data collection period, participants will return the PsyMate® to the lab
and will be compensated for their time and effort.

No health risks are involved in participating in the study and it is unlikely
that participants will directly benefit from their participation. The main
burden for participants is their time investment of 2,5 hours. None of the
computer task, questionnaires, or cortisol sampling procedures poses a risk for
the participants of the study. Given the experience with similar paradigms in
other studies at our department, as well as at the Department of Psychology of
the Maastricht University, we believe that the risks of participating in this
study are minimal.