External Pharyngeal Exerciser and Pharyngeal Phase of Swallowing

Inclusion Criteria:

* Healthy volunteers must be at least 18 years of age or older.

Exclusion Criteria:

* Subjects with cervical spine disorders.
* Subjects with neurological disorders like dementia, cerebrovascular diseases other than Parkinson's Disease
* Subjects with carotid artery bruit or carotid vascular disorders.
* Subjects suffering from muscle diseases like muscular dystrophies, myopathies.
* Subjects with neuro-muscular junction disorders myasthenia gravis, Eaton-Lambert disorders.
* Subjects with any current esophageal symptoms like heartburn, dysphagia, chest pain or regurgitation.
* Subjects cannot have previous head or neck surgery or radiation.
* Subjects unable to tolerate nasal intubation.
* Subjects with significant bleeding disorders for whom nasal intubation has been deemed contraindicated.
* Subjects with a known upper airway or esophageal obstruction preventing the passage of the manometry probe.
* Subjects with autonomic dysfunction.
* Subjects having a history of allergy to lidocaine and barium.
* Subjects who are pregnant or lactating.
* Subjects who have advanced medical disorders (e.g.: chronic obstructive pulmonary disease (COPD), congestive heart failure, cirrhosis, cancer, chronic renal failure, etc.).
* Subjects who are medically unstable.