The primary aims are to test the hypothesis that in depressed patients, an mPFC-related presence of negatively toned memory schemas contributes to a preferential encoding and subsequent REM sleep-related consolidation of negative stimuli, thus…
ID
Source
Brief title
Condition
- Other condition
- Mood disorders and disturbances NEC
Synonym
Health condition
neurowetenschappelijk onderzoek
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The primary aim of this project is to test the hypothesis that in patients
suffering from MDD, an mPFC-related presence of negatively toned memory schemas
and its interactions with the amygdala contributes to a preferential encoding
and subsequent REM sleep-related consolidation of negative stimuli, thus
developing and perpetuating a negative memory bias.
As a neurocognitive measure of (valence specific-) schema memory, we will
investigate the performance on the false memory recall and recognition task
(the remembering of related but never presented words i.e. false alarms) and
its neural correlates. Here, we aim to investigate the underlying neural
mechanisms (mPFC/ amygdala activity and connectivity) during both encoding and
retrieval and relate these to sleep parameters (amount REM, eye movement, power
differences per group. Furthermore, SSRIs are known to suppress REM sleep
differently depending on acute or chronic intake (Wilson and Argyropoulos,
2005). We therefore aim for disentangling the REM suppressing and non REM
suppressing side effects of the prescribed medication and its effects on the
memory task,
These measures combined will provide us the opportunity to explore the tight
relations between schema memory, memory bias, (REM) sleep and depression in
detail.
Secondary outcome
Additionally, we aim to examine the effect of group on mPFC/ amygdala and whole
brain post-encoding resting-state connectivity. Using exploratory correlational
analyses, we want to test for altered mPFC interactions with the amygdala in
particular. We expect these interactions to be augmented in participants
suffering from depression and that these interactions are related to enhanced
negative false memory persistence and decreased positive memory persistence.
Background summary
Memory bias for negative information is one of the major cognitive symptoms
causing and maintaining Major Depressive Disorder (MDD). The neural mechanisms
underlying memory bias are still rather elusive. The recently revived concept
memory schemas, denoting preexisting knowledge structures that enhance the
encoding and consolidation of new, but related information, may shed new light
on the neurocognitive mechanisms underlying memory bias in MDD. Sleep
contributes to memory consolidation, with affective and schema-related memories
being particularly associated with REM sleep, which in turn is disinhibited in
depression. On a neural level, the medial prefrontal cortex (mPFC) essentially
contributes to memory schema processing, and shows strong activation during REM
sleep.
Study objective
The primary aims are to test the hypothesis that in depressed patients, an
mPFC-related presence of negatively toned memory schemas contributes to a
preferential encoding and subsequent REM sleep-related consolidation of
negative stimuli, thus developing and perpetuating a negative memory bias.
Study design
The study is designed as a between subjects design. The study will include one
screening session, two fMRI sessions where a false memory task employed and two
nights of polysomnography before and between the MRI sessions.
Study burden and risks
All participants will visit the institute three times in total, including one
screening session, two scanning sessions of approximately 60 minutes each and
two days-time naps sleep recordings. Although the noise and the relative
confined space of the MRI scanner may cause discomfort to some participants,
MRI measurements themselves do not pose any risk if appropriate precautions are
made. The stay at the institute for the sleep recordings may additionally cause
mild discomfort to some participants due to the unfamiliar environment and the
attachment of multiple electrodes for sleep positioning. Risks associated with
all measurements are however negligible as there will be no measurements of an
invasive nature.. There will be no intervention of any kind of ongoing
treatment for patients.
Kapittelweg 29
Nijmegen 6525 EN
NL
Kapittelweg 29
Nijmegen 6525 EN
NL
Listed location countries
Age
Inclusion criteria
For patients:
* Males and females between 25-55 years of age
* Patients with an official diagnosed of unipolar major depressive disorder, without psychotic features (as defined by DSM-IV-TR)
* On antidepressant medication (SSRIs) for at least 2 weeks and a Hamilton score between at least 17 and 30.;For controls:
Males and females between 25-55 years of age
Exclusion criteria
* Presence of a current or past relevant somatic disorder
* Presence of comorbid bipolar disorder, schizophrenia or substance abuse disorder
* MRI-related exclusion criteria (i.e. claustrophobia, pregnancy, internal metal objects, etc.)
* Impossibility to obtain a valid informed consent
A control group matched for age and sex will be recruited. Exclusion criteria for the control group will be similar to the exclusion criteria for the treatment group, with the following additions:
* No current or past psychiatric illness
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL59345.091.16 |