Our primary objective is to translate an in non-human primate established online TUS protocol to humans. To this end, we will investigate how this protocol influences choice behaviour in humans, by stimulating the left and right FEF in a saccade…
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Brief title
Condition
- Other condition
Synonym
Health condition
Neuroscience research
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Oculomotor behaviour (leftward/rightward saccades) in the saccade-task is used
as the main outcome variable.
Secondary outcome
Secondary outcomes, such as saccade latency and duration will also be assessed
to study how TUS of the FEFs affects saccade preparation and duration.
Additionally, GABA/glutamate levels in the stimulation sites (using MRS) and
the intracranial stimulation intensity (calculated on each subjects structural
MRI) will be examined per individual to explain any inter-individual
differences in behavioural outcomes.
To assess individual location of the left/right FEF and the left/right M1,
which we need for stimulation during intervention sessions, we perform a short
functional MRI during the intake session.
Furthermore, as a quality control of this study, we have added the M1 as an
active control site and we will perform a masking assessment at the end of the
intervention sessions to guarantee the spatial specificity of TUS and the
quality of our auditory mask, respectively. All of these measures will help
ensure accuracy and precision of our findings
Background summary
Transcranial Ultrasonic Stimulation (TUS) is a non-invasive brain stimulation
(NIBS) technique with unmatched spatial specificity and the ability to target
nearly any brain region. To date, this technique is mostly studied in animal
models, while its translation to human applications is still at an early phase.
One of the current key aims is to develop TUS protocols to safely and
effectively modulate behaviour in humans, and understand the neural basis of
their effects. To achieve this critical translational goal, we leverage an
experimental design from a non-human primate study (Kubanek et al., 2020) using
TUS stimulation of the frontal eye field (FEF) to human participants. The FEF
is involved in voluntary eye movements to the contralateral side. Exciting the
FEF, therefore, drives eye saccades to the contralateral side, whereas
inhibition of the FEF steers saccades to the ipsilateral direction. We measure
the effect of FEF TUS stimulation on oculomotor behaviour to investigate the
physiological and behavioural effects of TUS in humans. Based on the non-human
primate findings reporting (Kubanek et al., 2020), we hypothesise that this
online TUS protocol will bias eye saccades contralateral to the TUS stimulated
FEF. This effort may indicate the potential of TUS in an online paradigm and
will further serve to inform the experimental design of future studies.
Study objective
Our primary objective is to translate an in non-human primate established
online TUS protocol to humans. To this end, we will investigate how this
protocol influences choice behaviour in humans, by stimulating the left and
right FEF in a saccade task.
Study design
The present study will be a single-blind, three-visit, randomised, sham- and
active-controlled trial. In the first session, structural and functional MRI
scans will be obtained, during which participants perform a FEF localiser task
and a hand primary cortex (M1) localiser task. We will also obtain a MRS scan
to assess the GABA/glutamate concentrations in the FEF and M1. The second and
third session are the intervention sessions in which the left and right FEF,
and left and right M1 will be stimulated (with sham) while the participants
perform a saccade-task. The intervention sessions also include a final masking
assessment, to ascertain that the participants were successfully blinded to the
conditions.
Intervention
Participants will receive TUS at a standard sub-threshold intensity.
Study burden and risks
Participants, apart from the reimbursement they receive and the experience of
participating in a brain stimulation study, have no further benefit from
participating in this study. Participants will receive a standard financial
compensation where applicable. Before participation, all subjects will be
screened for contraindications with respect to TUS and magnetic resonance
imaging (MRI). The estimated risk for participating in MRI measurements and
TUS-based interventions is minimal. The noise and the relative confined space
of the MRI scanner, and the requirement to remain seated during the TUS
experiment, may cause discomfort to some subjects. TUS for human
neuromodulation has never resulted in serious adverse events (Blackmore et al.,
2019; Pasquinelli et al., 2019). Similar to applications of well-established
biomedical ultrasound (Ter Haar, 2010), safety of study participants is ensured
by adherence to internationally recognized practices and guidelines (e.g., from
the Food and Drug Administration). Minor side effects of TUS may include light
transient headache and fatigue (Legon et al., 2020). To conclude, the risk and
burden associated with participation is considered minimal, and we do not
expect any (serious) adverse events during the project.
Thomad van Aquinostraat 4
Nijmegen 6525GD
NL
Thomad van Aquinostraat 4
Nijmegen 6525GD
NL
Listed location countries
Age
Inclusion criteria
- Between 18-40 years of age
- Right handed
- The ability and agreement to provide informed consent, and the ability to
fulfil the study's requirements
Exclusion criteria
• Under 18 years of age;
• Current or planned pregnancy;
• Claustrophobia;
• A history or brain surgery or serious head trauma;
• A history of or any close relatives (parents, siblings, children) with
epilepsy, convulsion, or seizure;
• Predisposition for fainting spells (syncope);
• A cardiac pacemaker or intra-cardiac lines;
• An implanted neurostimulator;
• Implanted medication infusion device;
• Implanted metal devices or large ferromagnetic fragments in the head or upper
body (excluding dental wire), or jewellery/piercing that cannot be removed;
• Use of a medical plaster that cannot or may not be taken off (e.g., nicotine
plaster);
• Cochlear implants;
• Metal in the brain, skull, or elsewhere in your body (fragments, clips,
etc.);
• Diagnosed neurological or psychiatric disorders;
• Use of psychoactive (prescription) medication (excluding anti-conception);
• Skin disease at intended stimulation sites;
• The consumption of more than four alcoholic units within 24 hours before
participation or any alcoholic units within 6 hours before participation day;
• The consumption of recreational drugs within 48 hours before participation;
• Calcifications in the brain.
• All other criteria relevant to non-invasive brain stimulation as reported in
the Donders Standard Operating Procedures for Non-Invasive Brain Stimulation.
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 |
|---|---|
| CCMO | NL82309.091.22 |