The main objective of the present study is to determine the role of dopamine and stress in functional connectivity in neural substrates for habitual- and goal-directed behaviour and their effects in subsequent behaviour.
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
basaal wetenschappelijk onderzoek
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Main dependent variables are the fMRI measure of functional connectivity
between the medial aspect of the striatum and the orbitofrontal cortex, and
between the amygdala and lateral putamen, and the performance on an
instrumental learning task.
Secondary outcome
Additional dependent variables are and neuroendocrine stress markers (cortisol
and salivary alpha-amylase), and performance on two impulsivity tasks.
Background summary
Stress is omnipresent in our modern society. Our psychophysiological responses
to stress, generally serve adaptive purposes such as promoting the use of
simple but fast habits over complex goal-directed behaviour. Nevertheless, such
a preference for habitual behaviour under stress may, in vulnerable
individuals, constitute a risk factor for psychopathology. For example, stress
often precedes emotional eating and binge eating episodes, and is reported by
people with a substance addiction as a primary reason for relapsing.
Unfortunately, not much is known about the neural mechanism of this stress
induced shift towards the use of habits. We do know that different neural
circuits govern automatic (amygdala, posterior lateral putamen) and
goal-directed (medial striatum, orbitofrontal cortex) behaviour. In addition,
dopamine has been shown to play an important role in addictive behaviour,
pleasure and reward. What is currently unknown is whether stress and dopamine
activity can modulate communication in the habitual- and goal-directed
behaviour neural substrates.
Study objective
The main objective of the present study is to determine the role of dopamine
and stress in functional connectivity in neural substrates for habitual- and
goal-directed behaviour and their effects in subsequent behaviour.
Study design
The study is a 2x2 (drug*stress) between volunteers, double blind experiment.
Intervention
Participants will receive either a single oral dose of methylphenidate 40 or
placebo, and will experience an incidence of stress induction or a no-stress
control manipulation
Study burden and risks
Participants will visit our facilities twice. The first visit entails a full
medical screening ensuring their safety, which will include taking a blood
sample through venipuncture and making an electrocardiogram. The second visit
will consist of (1) taking study treatments (methylphenidate or placebo), (2)
undergo a stress manipulation or a control manipulation, (3) taking saliva
samples, and (4) filling out questionnaires and doing computer tasks inside and
outside the magnetic resonance scanner (60 minutes). During the periods that
they are not tested (breaks), they will be seated in a waiting room where they
will be in close contact with one of the researchers. In case they experience
(medical) complaints, the medical supervisor will be contacted. The total
discomfort experienced by the volunteer is minimal when all precautions are
taken into account. Most important precautions are: determining the absence any
mental or physical disorder that may interact with methylphenidate, and having
volunteers experience lying inside a dummy scanner. Blood samples will be taken
by an experienced member of our team. Finally, the stress manipulation has been
shown to be well tolerated.
Universiteitssingel 40
Maastricht 6229 ER
NL
Universiteitssingel 40
Maastricht 6229 ER
NL
Listed location countries
Age
Inclusion criteria
- good physical and mental health as determined by medical history and medical examination, ECG and laboratory examination;
- BMI between 19 and 25 kg/m2;
- use of appropriate contraception;
- written informed consent;
- age between 18-35 (inclusive)
Exclusion criteria
- pregnancy or lactation;
- cardiovascular abnormalities as assessed by standard ECG;
- excessive alcohol use, defined as drinking more than 21 glasses of alcohol per week;
- history of drug abuse or addiction;
- hypertension (diastolic> 90; systolic> 140);
- history of psychiatric and neurological disorders
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
In other registers
| Register | ID |
|---|---|
| CCMO | NL57634.068.16 |
| OMON | NL-OMON20107 |