Our primary objective is to provide a model which accounts for the inconsistencies in the pharmacological literature regarding the role of the noradrenergic and cholinergic system in visuo-spatial attention. Recently we started a University Medical…
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Geen aandoening; geneesmiddel wordt gebruikt om selectief een aandachtssysteem te inhiberen dmv cholinergisch agonisme
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Behavioural measures:
In the VSC (Visual Spatial Cueing) paradigm: the validity effect in ms (RT
valid cued target - RT invalid cued target).
A larger validity effect reflects either more bias, or less disengagement.
In the stop task paradigm, the time needed (in milliseconds) to abort a
prepotent response: the Stop Signal Reaction Time (SSRT); SSRT reflects
inhibition and related disengagement but is also dependent on bias.
Neurophysiological (Event Related Potentials, task related brain activity)
endparameters in the VSC:
1) Parietal cue Event Related Potential (ERP) components.
These are the Anterior Directing Attention Negativity (ADAN) and the Late
Directing Attention Positivity (LDAP). Both are related to bias.
2) P1 ERP (following a validly cued target); associated with bias.
3) Late Positive Deflection (LPD) ERP (following an invalidly cued target);
associated with disengagement.
Neurophysiological (ERP) endparameters in the stop task:
1) N2 ERP (following the onset of a stopsignal), associated with disengagement.
2) LPD ERP (following the onset of a stopsignal), associated with
disengagement.
Secondary outcome
Dependent variables are identical to the primary parameters. The independent
variable is a subject variable: smoker/non-smoker. (See protocol for details).
Background summary
For the development of better pharmacological treatment of various pathologies
in which attention and impulsivity
are implicated, such as ADHD, it is crucial to gain knowledge about the
neurobiological basis.
Two neurobiological mechanisms are implicated in visuospatial attention, bias
and disengagement. bias refers to
increased sensory information processing due to the orientation of attention.
Disengagement refers to the
interruption of that attentional set, making processing of non attended stimuli
possible. The dominant theory
posits that bias rests on cholinergic functioning and disengagement depends on
noradrenergic functioning.
Results of pharmacological research are inconsistent and suggest the opposite.
In this research, the cholinergic part of an
alternative model which states the opposite of the dominant model but accounts
beter for pharmacological results is
proposed and evaluated.
Study objective
Our primary objective is to provide a model which accounts for the
inconsistencies in the pharmacological literature regarding the role of the
noradrenergic and cholinergic system in visuo-spatial attention. Recently we
started a University Medical Center (UMC) Utrecht METC approved study aimed at
testing the noradrenergic part of the model using Clonidine. In the current
study, our aim is to test the second - cholinergic - part of this model. Our
secondary objective is to explore possible differences between smokers and
non-smokers. It could be possible that nicotine abstinent smokers show less
disengagement related activity as opposed to non-smokers due to either
long-term effects of nicotine, or due to a possible inherent disengagement
related deficit.
Study design
A single blind placebo-controlled crossover design will be used in which the
order of the drug conditions (placebo, nicotine) and computer tasks (VSC, SST)
will be counterbalanced across participants.
Intervention
Nicorette Freshmint 2mg will be used for manipulating (facilitating) the
cholinergic system.
Study burden and risks
Participants have to fill out a questionnaire twice, the Profile Of Mood States
(POMS). This will take in total approximately 10 minutes.
Participants will perform on two computer tasks with a total duration of
approximately 110 minutes, while EEG is recorded.
EEG is a non-invasive method, but some electrode gel (salt solution) will be
applied between the scalp and electrodes which participants
may wash out after the experiment at location. No significant side effects are
expected for the administered dose of Nicorette Freshmint 2mg.
To conclude, to our opinion the importance of the proposed research outweighs
the minimal burden and risks for participants, which is why we believe the
research to be justified.
Heidelberglaan 2, van Unnik gebouw, kamer 17.10
3584 CS Utrecht
NL
Heidelberglaan 2, van Unnik gebouw, kamer 17.10
3584 CS Utrecht
NL
Listed location countries
Age
Inclusion criteria
participants must be male and between 18-40 years old.
Exclusion criteria
- Hypersensitivity to nicotine or other substances in the chewing-gum
- oral infection or pharyngitis
- active oesophagitis
- (history of) cardiovascular disease
- liver failure / insufficiency
- Kidney failure / insufficiency
- Diabetes mellitus
- Use of medication
Design
Recruitment
Medical products/devices used
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 |
|---|---|
| EudraCT | EUCTR2010-021222-35-NL |
| CCMO | NL32831.041.10 |