Attention-dependent modulation of TMS-evoked EEG potentials in early visual cortex

Completed

Conditions: nvt
na

Registration Number: NL-OMON37221

Lead Sponsor: Radboud Universiteit Nijmegen

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 48

Inclusion Criteria

Only healthy, competent, right-handed participants, 18*45 years old, with normal vision or corrected-to normal vision by means of contact lenses, able to consistently perceive phosphenes evoked by single-pulse TMS of the visual cortex will be recruited.

Exclusion Criteria

- Epilepsy, convulsion or seizure
- Serious head trauma or brain surgery
- Large or ferromagnetic metal parts in the head (except for a dental wire)
- Implanted cardiac pacemaker or neurostimulator
- Pregnancy
- Large of ferromagnetic metal parts in the body
- Claustrophobia
- Skin diseases at intended electrode sites
- Disorders of vision (i.e., deviation from *normal or corrected-to-normal vision*)
- History or current presence of any neurologic or psychiatric disease
- Any prescribed medication that can alter cortical excitability (e.g. antiepileptics, tricyclic anti-depressives or benzodiazepines) or can have an influence on the participant*s vigilance or cognitive performance within two weeks prior to participation

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>To study the relationship between TMS-evoked and spontaneous alpha<br /><br>oscillations. We expect TMS-evoked and spontaneous alpha oscillations to<br /><br>respond similarly to changing levels of visual attention. More specifically, we<br /><br>expect attention to the visual stream to result in a decrease of both the<br /><br>amplitude and power of spontaneous as well as TMS-evoked alpha oscillations,<br /><br>whereas attention to the auditory stream should result in an increase of both.<br /><br>We further expect that individual frequency and amplitude of TMS-evoked and<br /><br>spontaneous oscillations correlate across subjects. </p><br>

Secondary Outcome Measures

Name	Time	Method
<p>To investigate the feasibility of transcranially inducing specific brain<br /><br>oscillations in order to establish a causal link between neuronal oscillations<br /><br>and cognition. Starting out from single-pulse TMS-evoked oscillations we hope<br /><br>to also improve the understanding of how frequency-specific repeated<br /><br>perturbations (i.e., repetitive TMS) can be used to modulate spontaneous brain<br /><br>oscillations in health and disease. </p><br>