In the present study, we investigate the role of the STN in different conditions.In earlier research, we found that the STN is involved in response selection and inhibition. This was investigated using behavioral measurements. Currently, we want to…
ID
Source
Brief title
Condition
- Movement disorders (incl parkinsonism)
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Mechanisms of cognitive control and inhibition
a. simple RT-task, a single stimulus is presented and the subject has to
respond by pressing a button as soon as possible
b. choice RT-task, a light on the left or the right side of the monitor shows
up and the the subject has to press a button as soon as possible ipsilateral to
the stimulus presented
c. GO/NOGO task, after a warning stimulus a GO-stimulus (e.g. green light,
press the button) is presented or a NOGO stimulus (e.g. red light, do not press
the button)
d. STOP-task, similar to the preceding GO/NOGO task, but some of the GO stimuli
(e.g. green light) will directly be followed by an overrulling STOP stimulus
(e.g. red light)
Perception of emotional expression and body-language
Patients are placed within a Faraday cage in front of a monitor. The monitor
shows simultaniously faces with various expressions. The patient has to decide
and subsequently indicate with a button press which faces are showing a similar
expression. In a comparable task, instead of faces pictures of bodies are used.
Subjects have to decide which bodies have a similar emotion value.
Motoric and sensoric timing
In a tapping task, where a number of clicks are presented in a fixed rhythm,
the patient is asked to tap according to the auditory stimuli and after
discontinuation of the auditory stimuli, he or she has to continue tapping in
the rhythm.
Next a discrimination task will be excecuted. Two small light are presented
with variabel intervals. The first light will flash 500ms, 1000ms, or 1500ms.
The second may shorter, identical, or longer and the subject has to decide
which is the case.
Secondary outcome
Not applicable
Background summary
Neuropsychology tries to relate behavior and the function of relevant brain
structures. In general, normal subjects or patients participate in
neuropsychological research. In addition, systematic research in animals
(including primates). These consist of intracortical measurements of brain
activity during the performance of various tasks. In some laboratories
intracortical recordings during different simple motor tasks (e.g. finger
movements) are also done in patients with epilepsy. In the present study,
behavioral and electrophysiological recordings are made in patients with
Parkinson's disease and deep brain stimulation of the STN.
Study objective
In the present study, we investigate the role of the STN in different
conditions.
In earlier research, we found that the STN is involved in response selection
and inhibition. This was investigated using behavioral measurements. Currently,
we want to investigate whether there is a brain cortex correlate.
In addition, we want to study whether the perception of emotion in patients
with Parkinson's disease is impaired. This has been demonstrated for the
perception of angry faces, but not yet for somatic expressions nor for context
effects.
It is hypothesized that the nigro-striatal projection functions like a
pacemaker for the estimation of time-intervals. Disturbances of the basal
ganglia may result in a impaired estimation and impaired generation of
time-intervals. Dopamine deficiency may cause a disruption of this pacemaker
function, as was shown before by the improvement of timing with the precursor
levodopa substitution. To date, the effect of deep brain stimulation of the STN
upon time estimation has not been investigated.
Study design
Two outcome parameters will be used.
1) behavior
Several tasks will be presented, assessing speed and accuracy of reactions.
These are variants of reaction-time tasks.
2) electrophysiology
Electro-cortical brain (EEG) and, if necessary, the electrical muscle activity
(EMG) will be measured. Of special interest are the event-related potentials
(ERPs), which will be derived from the EEG.
Study burden and risks
Apart from the time invested by the patients, there is no extra burden.
Patients can turn the deep brain stimulation OFF and ON by themselves; this is
without risks. If the stimulator is turned OFF, patients may experience the
return of symptoms which the deep brain stimulation supresses. These will
disappaer when turning ON the stimulator. The study does not have any risks.
Meibergdreef 9
1105 AZ Amsterdam
NL
Meibergdreef 9
1105 AZ Amsterdam
NL
Listed location countries
Age
Inclusion criteria
Patients with parkinson's disease
bilateral STN deep brain stimulation
Exclusion criteria
below normal intelligence
severe motoric disturbances
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 | NL26846.018.09 |