The purpose of this study is to 1) determine whether differences exist in central control of voluntary swallowing in young and elderly healthy non-dysphagic individuals, and 2) determine if a lingual exercise regimen will focalize neuronal activity in healthy young and/or elderly subjects without dysphagia. Cortical reorganization and increased focal neuronal activity may be induced with lingual exercises in healthy and dysphagic young and elderly individuals who have demonstrated lingual strengthening. Corticlal reorganization due to strength training is important because the brain may adapt to facilitate better swallowing in people with mild to severe dysphagia. Increased neural activity in tongue and swallowing–related areas of the brain might reduce neural activity in unrelated areas that likely interfere with safe, efficient swallowing.
Participants will perform tongue exercises for eight weeks. MRI scans will be performed at baseline, 4 weeks, and 8 weeks into the study. T2-weighted MR images with and without fat suppression will be used to quantify volumetric aspects of the intrinsic and portions of the extrinsic lingual musculature. Additionally, fMRI scans will be performed to monitor the activity of the brain. During the fMRI scans, participants will exercise their tongues, swallow, or relax and brain activity during each of these tasks will be determined.