2 Functions Detects sound Helps maintain balance Maintains alertness Aids emotion, memory, detection of body language and thought
3 Parts of the Ear There are 3 parts that make up the ear External Ear: Includes the auricle (pinna), the auditory canal and the eardrum.Middle Ear: Comprised of the 3 smallest bones in the human body. These are the malleus (hammer), the incus (anvil) and the stapes (stirrup).Inner Ear: Where the cochlea is located. The cochlea is filled with liquid that helps the body maintain its balance. The cochlea also has about 20,000 cells that transmit signals to the brain. These are called ciliated cells.
11 CochleaThe cochlea is a snail-shell shaped part of the ear divided into 3 different parts filled with fluid.Tympanic Canal (Perilymph fluid)Vestibular Canal (Perilymph fluid)Cochlear Duct (Endolymph fluid)
12 CochleaThese liquids move around in response to sound waves being received from the middle ear. As the perilymph moves, the cochlear partition moves. As the cochlear partition moves, thousands of ciliated cells sense the motion and turn it into electrical signals which are then sent to the brainstem.
15 Organ of CortiThis is the part of the ear that is filled with 16,000-20,000 of hair cells. When these hairs are moved, they send messages to the brain.
16 Eustachian Tube Adjusts the air pressure in the ear drum and connects the ear to the nose.
17 Auditory NerveTakes electrical impulses from the cochlea and makes connections with the auditory area of the brain.
18 How Can We Hear? Sound waves travel into the ear and reach the eardrum The eardrum passes the vibrations from the sound waves through the middle ear bones and into the inner earWhen these vibrations reach the cochlea, the ciliated cells convert the vibrations into electrical signalsThen, these signals are sent to the brain via the auditory nerve
19 What Causes Deafness? Head trauma Aging Hereditary hearing loss DiseaseExposure to loud noises
20 Conductive Hearing Loss When hearing loss is because of problems with the external or middle ear. Causes include: allergies, impacted earwax, tumors, infection, fluid in the middle ear, malformation Can be treated with surgery
21 Sensorineural Hearing Loss When hearing loss is because of problems in the inner ear. Causes include: exposure to loud noise, head trauma, malformation, otosclerosis, Menieres disease Can be treated with surgery or therapy
22 OtosclerosisAn abnormal bone growth in the middle ear that prevents vibrations to be passed on thought the ear.
23 Menieres DiseaseInner ear disorder that causes hearing loss and episodes of vertigoNamed after a French physician, Prosper Ménière, who first said that vertigo was caused by inner ear disordersSymptoms: pressure in ears, vertigo, migraineCauses: when fluid from the inner ear leaks and goes into other areas of the earTreatments: surgery, physiotherapy
24 Earwax Medical Term: cerumen Assists in cleaning and lubrication and provides protection from bacteria, water, and fungi