Functional Manifestations of Pressure Changes in the Middle Ear System

Functional Manifestations of Pressure Changes in the Middle Ear System: An fMRI Study

This study is looking at whether functional magnetic resonance imaging (fMRI) can see if and when the brain responds to pressure stimulations of the eardrum. The study requires 2 visits, 1 for screening to determine eligibility and 1 for the fMRI. This study will help to understand how the middle ear system is controlled, which may have an impact on how people with middle ear disease are treated.

Otitis media is a ubiquitous disease in young children which can persist through adolescence, and arise or recur in adults. A consequence of an infection and/or Eustachian tube dysfunction, it manifests as an effusion that disrupts the normal impedance matching function of tympanic membrane-ossicular chain system. Eustachian tube dysfunction prevents the equilibration of middle ear pressures and drainage of the accumulated effusion. It is thought that middle ear status modulates the function of the Eustachian tube via afferent signals processed centrally resulting in changes in its tonus or muscular function. This pilot study of right-handed 21-35 year olds of either sex will validate a published fMRI method for visualizing cortical brain activation in response to external ear canal pressure changes (N=5). The outcome measure is intensity changes of the cortex associated with applied stimuli.

Inclusion Criteria:

• 21-35 years of age
• right-handed

Exclusion Criteria:

• left-handedness or ambidexterity
• fMRI safety reasons (ferromagnetic material in their bodies, epilepsy, claustrophobia
• history of middle ear/tympanic membrane surgery (tympanostomy tubes)
• abnormal otoscopic findings and/or tympanometry on physical exam
• pregnancy