Find the stimulation threshold of the facial nerve (ganglion Geniculate) associated with tolerability and safety in subjects Healthy humans.

Magnetic stimulation of the facial nerve (geniculate ganglion) in humans can induce changes in cerebral blood flow safely, without generating adverse effects unknown to the technique.

Our specific objectives:

1. Perform tolerability and safety tests of magnetic stimulation on the facial nerve.
2. Establish the optimal stimulation threshold associated with tolerability in order to apply it to the final design of the Magnetic Stimulation (MS) system.
3. Measure whether the threshold found shows any increase in cerebral perfusion in the subject with respect to their baseline.

Inclusion Criteria:

• Healthy subjects
• Normal audiometry chart (Evaluated at the time of your inclusion).
• Normal neurological examination at time of inclusion.

Exclusion Criteria:

• Subjects with a diagnosis of epilepsy, seizures, facial nerve palsy, migraine or recurrent headaches, glaucoma or neuropathies.
• Subjects in breastfeeding or in pregnancy. (To be confirmed with test strip).
• Subjects with acute or acute chronic medical conditions.
• Age less than 20 years or greater than 40 years.
• Carotid surgery.
• Episodes of syncope.
• Known arteriosclerosis anywhere on the body
• Metal implants (cochlear implants, pacemakers, metal prostheses).
• Intracranial abnormalities observed by MRI or MRA (Evaluated at time of inclusion of the subject).
• Intraocular pressure> 22mmHg (Evaluated at time of inclusion of the subject)

available from investigators authors upon reasonable request