In this study, we will systematically investigate the influence of distractors on target processing in patients with lesions to the frontal, parietal and occipital system. This will be measured by eye movements. Furthermore, prism adaptation will be…
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Source
Brief title
Condition
- Structural brain disorders
Synonym
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The main endpoint of the present study is the latency (reaction time) of the
eye movement. This is measured as the time between the presentation of the
target and the start of the eye movement.
Secondary outcome
The secondary study parameters are the saccade metrics like saccade
trajectories and endpoint. Furthermore, it will be investigated whether the
prismatic effect is more perceptual or more motor in nature, or a combination
of both. The data for this will come from the neuropsychological neglect
screening, in which changes in performance on screening tests with a strong
perceptual component (e.g. Landmark task) will be compared to changes in
performance on screening tests with a strong motor component (e.g. Star
Cancelation). Additionally, differences in eye movements (reaction times,
endpoints) between pre- and post prism adaptation will be investigated.
Background summary
We propose to study the effects of unilateral brain damage to the frontal,
parietal and occipital system on goal-directed behavior. Humans frequently make
eye movements to explore their daily environment. Because of the wealth of
visual information in our environment, there is a continuous competition
between the various elements in the visual field for the next eye movement.
Crucial is therefore the correct selection of the relevant element (*target*)
in the presence of irrelevant elements (*distractors*). Previous studies have
shown that distractors interfere with target processing in that eye movement
responses to a target are slower and less accurate. Moreover, in a small
proportion of trials, the eyes are captured by the distractor in that eye
movements are erroneously directed to the distractor. There is behavioral
evidence that patients with damage to certain brain areas show abnormal
distractor interference. However, the role of the various areas on target
selection and distractor interference is largely unknown.
Study objective
In this study, we will systematically investigate the influence of distractors
on target processing in patients with lesions to the frontal, parietal and
occipital system. This will be measured by eye movements. Furthermore, prism
adaptation will be used to investigate whether adaptation changes the
competition between target and distractor. The prismatic aftereffect will first
be tested with a brief neuropsychological neglect screening, which will be
compared to the performance prior to prism adaptation. Prism adaptation will
only be investigated in patients with lesions to the parietal and occipital
system.
Study design
This is a group study (n=81) in which adult participants with lesions to
frontal, parietal or occipital systems are invited to participate in a
behavioral study to investigate the brain mechanisms underlying the competition
between visual targets. Our goal is to have an equal number of patients for the
three different groups. A control group (n=27), matched in age, will be tested
using the same experimental set-up.
Study burden and risks
This is a non-therapeutic study in which the risks are negligible and the
burden is minimal. The experiments are non-invasive, so there is no need for
special preparation for the participants. There are no health risks doing the
tests. The data are primarily used for research purposes.
Heidelberglaan 2, kamer 17.12
3584CS
NL
Heidelberglaan 2, kamer 17.12
3584CS
NL
Listed location countries
Age
Inclusion criteria
- aged older than 18 years and younger than 80 years
- having suffered brain damage frontal, parietal or occipital systems
- able to understand and carry out the test instructions
Exclusion criteria
- psychiatric conditions that might interfere with the test performance
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 | NL20247.041.07 |