The main objective of this study is to investigate the neural and cognitive origings of spatio-numerical associations.
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
fundamental research on healthy volunteers
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
Spatial-numerical interactions will be indexed by the slope coefficient for the
regression of dRT (horizontal: right response * left response; vertical: up
response * down response) against numerical magnitude (1,2,3,4,6,7,8,9 see
Fias, Brysbaert, Geypens, & d*Ydewalle, 1996).
Secondary outcome
not applicable.
Background summary
Research on the mental representation of number has provided strong evidence
for a tight coupling of numerical and spatial codes. The cognitive and neural
origins of these couplings, however, are still poorly understood. A crucial
question in this regard is, whether spatio-numerical associations (SNA*s)
reflect a stable and functional association of space and numerical magnitude or
a spontaneous and highly flexible spatial mapping of numerical symbols. In the
current study, we will investigate the role of the right intraparietal sulcus
(IPS), a region that has been shown to represent spatial and numerical codes,
for SNA*s. We will apply offline 1 Hz repetitive transcranial magnitude
stimulation (rTMS) to the right IPS, which causes a transient disruption of
cortical activity at the stimulation site. Afterwards, participants will
perform a parity judgment task with either horizontally or vertically aligned
responses. The, study will enhance our understanding of the mental and neural
representation of numerical knowledge. Therefore, it might also provide
important implications for teaching methods of basic numerical competencies.
Study objective
The main objective of this study is to investigate the neural and cognitive
origings of spatio-numerical associations.
Study design
A randomized sham-controlled within subjects design.
The experiment consists of three sessions, one intake and two test sessions
During the intake sessions participants will again be informed about the study
by the investigator upon arrival at the TMS lab of the DCC. All procedures will
be explained in detail. Participants will be given sufficient time to ask
questions that will be answered by the investigator. Participants will then
sign the informed consent forms. Informed consent will be obtained before each
test session. A standard health- and safety questionnaire for non-invasive
brain stimulation will also be handed out. Right-handedness will measured with
the Edinburgh questionnaire. Participants will be familiarized with the TMS
procedure, and their individual motor threshold (MT) from the right or left
primary motor cortex using the thumb movement visualization method will be
measured to determine stimulation intensity (Schutter & Van Honk, 2006).
During the experimental session participants will first practice the task.
After successfully finishing the practice phase, the experimental task will
begin. Participants will receive a 20-min 1-Hz train of pulses of rTMS real or
sham rTMS to the left IPS at 80% Motor threshold. Afterwards a parity judgment
task will be performed (group 1: vertical responses, group 2: horizontal
responses).
Study burden and risks
The currently proposed TMS paradigm is safe and does not carry any significant
risks. Safety guidelines will be followed to ascertain participants* safety.
Potential side-effects of TMS are tingling sensations under the electrodes,
muscle tension and headache. These are generally mild discomforts that respond
promptly to paracetamol (500mg). Volunteers can withdraw from the study at any
given time and there are no direct benefits for the participants. The risk that
the current application of the techniques as described in this protocol result
in an insult is negligible (Nitsche et al. Brain Stimulation 2008 1 206-223;
Rossi et al. Clin Neurophysiol. 2009 120 2008-39).
Montessorilaan 3
Nijmegen 6525 HR
NL
Montessorilaan 3
Nijmegen 6525 HR
NL
Listed location countries
Age
Inclusion criteria
18-35 years, non smoking, right-handed
Exclusion criteria
Skin disease, metal in cranium, use of psychotropic drugs, including cannabis, XTC, amphetamines and cocaine, epilepsy or family history of epilepsy, history of closed-head injury, history of neurological or psychiatric disorders, medication use (i.e. benzodiazepines, antidepressants and neuroleptica), cardiac pacemaker, electronic hearing devices, pregnancy
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 | NL51565.091.14 |