DRUG DESCRIPTION. NAMENDA XR is an orally active NMDA receptor antagonist. The chemical name for memantine hydrochloride is 1-amino-3,5-dimethyladamantane hydrochloride with the following structural formula: The molecular formula is C12H21Nâ¢HCl and the molecular weight is 215.76.
There are three main parts to the ear, including the inner ear, middle ear and outer ear. In order for hearing to occur, there is a sequence of actions that must occur to transform waves of sound in the air into electrical impulses. These impulses are transmitted to the brain by the auditory (hearing) nerve.
Figure 6. shows Amplification of sound waves: The middle ear is Hammer, Anvil, Stirrup. The pressure of sound waves moves this small membrane back and forth. The vibration of the eardrum moves three small bones, the ossicles, which transmit the vibrations to the inner ear.