The Ear, Sound, Hearing, and the answer to everything?

Essential Question How do we hear? What does the auditory system (ear + brain) look like and how does it work? Objectives Name the parts of the ear? Describe how sound is heard? Explain how energy, sound waves, and hearing are related.

The Ear Activity Draw and label, do not copy and paste. Estuation tube Anvil Hammer The ear is embedded in the temporal bone of the skull and is divided into three sections. Stirrup Estuation tube From www.unc.edu/courses/psyc21/3-26-99/sld008.htm From www.unc.edu/courses/psyc21

What does the auditory system look like and how does it work? We spend a lot of time on the ear, just a little time on the brain. We start at the outside and work our way in.

Hearing… The hearing system is based solely on physical movement. (Not chemical such as smell and taste). Sound occurs when it vibrates in matter. (Solid, Liquid, Gas). Copyright © 2010 Ryan P. Murphy

To hear, you must… Direct the sound waves into the Ear Canal using the Pinna aka the Outer ear: Pinna Copyright © 2010 Ryan P. Murphy

Function of Outer Ear Collect sound Focuses sound Reverberator Protection Sensitive (earlobe)

Pinna The visible portion that is commonly referred to as "the ear" Helps localize sound sources Directs sound into the ear Each individual's pinna changes the acoustic wave traveling into the auditory canal and everyone hears differently

External Ear Care Hazardous to health: Ear candling Swabs Foreign objects

Middle Ear  1999, Electronic Deaf Education Network

Function of Middle Ear Conduction Protection Transducer Amplifier Conduct sound from the outer ear to the inner ear Protection Creates a barrier that protects the middle and inner areas from foreign objects Transducer Converts acoustic energy to mechanical energy Converts mechanical energy to hydraulic energy Amplifier only about 1/1000 of the acoustic energy in air would be transmitted to the inner-ear fluids (about 30 dB hearing loss)

Middle Ear Tympanum: Timpani, or kettledrums, are musical instruments in the percussion family. A type of drum, they consist of a skin called a head stretched over a large bowl commonly made of copper.

To hear, you must… Direct the sound waves into the hearing part of the ear to the ear drum. The eardrum senses the fluctuations in air pressure. Pinna

Tympanic Membrane: The Eardrum The eardrum separates the outer ear from the middle ear Creates a barrier that protects the middle and inner areas from foreign objects Cone-shaped in appearance about 17.5 mm in diameter The eardrum vibrates in response to sound pressure waves. The membrane movement is incredibly small as little as one-billionth of a centimeter

Eustachian Tube provides a way to equalize the pressure between in middle ear and outer ear The Eustachian tube connects the tympanic cavity with the throat. The Eustachian tube functions to adjust the air pressure in the tympanic cavity. From www.unc.edu/courses/psyc21/3-26-99/sld010.htm

Ossicles: Bones of the middle ear M. Malleus (hammer) I. Incus (anvil) S. Stapes (stirrup) smallest bone of the body

To hear, you must… Direct the sound waves into the hearing part of the ear. Sense the fluctuations in air pressure in the ear drum and ossicle bones. Translate these fluctuations into an electrical signal in the Cochlear organ and out through the auditory nerve that your brain can understand. Pinna

Question The function of the inner ear: Balance Hearing Touch All the above A and B

The inner ear houses our organs of balance Organs of balance are part of the inner ear They include Semicircular canals These organs sense body position and movement Student Misconceptions and Concerns 1. Lectures on the sensory systems of humans present numerous opportunities to relate new information to familiar student experiences. For example, the functions of the pinna of the ear can be demonstrated by cupping one hand around the pinna, boosting its ability to detect sound. Consider other simple demonstrations and explanations relating common experiences to the structure and function of the senses. 2. The natural tendency to wonder about our world seems to fade with increasing education. Discussions of the human sensory systems can rekindle that curiosity in your students, if time is available to field their questions. Perhaps you might have your class ask questions about their sensory experiences on 3  5 cards, which you can later answer selectively as time permits. Teaching Tips 1. Students might wonder why their voice played back on a recording sounds different from what they hear when they speak. When we hear our own voice, many of the vibrations are transferred from our throat to our ear via bones and cartilage. These materials transfer the sound differently and thus do not sound the same as our voice transmitted through air. 2. The lumping together of hearing and balance in the five senses learned in elementary school may result in a decreased appreciation for the sense of balance. Yet, hearing and balance are clearly separate senses. (Hearing-impaired people can still walk!) Consider asking your students to close their eyes and tilt their heads in different directions. How can they tell the position of their heads? In addition to the semicircular canals, stretch receptors in the neck provide positional information. Copyright © 2009 Pearson Education, Inc.

Learn more about the ear, hearing, and hearing loss at… http://www

Answer in your ISN The correct order of the ossicles from the ear drum to inner ear is? Anvil, hammer, stapes Hammer, incus, anvil Hammer, anvil, stapes Stapes, anvil, hammer Malleus, stapes, incus

Answer in your ISN: the next slide shows the answers. Word Bank: Ear Drum, Eustachian Canal, Anvil, Cochlea, Hammer A tiny bone that passes vibrations from the hammer to the stirrup. A spiral-shaped, fluid-filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form. (Also called the tympanic membrane) a thin membrane that vibrates when sound waves reach it. A tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside. A tiny bone that passes vibrations from the eardrum to the anvil. Copyright © 2010 Ryan P. Murphy

Use Deductive Reasoning. (Frontal Cortex) Use your deductive reasoning skills: Word Bank: Ear Drum, Eustachian Canal, Anvil, Cochlea, Hammer Anvil - A tiny bone that passes vibrations from the hammer to the stirrup. Cochlea - A spiral-shaped, fluid-filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form. Eardrum -(Also called the tympanic membrane) a thin membrane that vibrates when sound waves reach it. Eustachian Canal - A tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside. When your ears pop as you change altitude (going up a mountain or in an airplane), you are equalizing the air pressure in your middle ear. Hammer - A tiny bone that passes vibrations from the eardrum to the anvil. Copyright © 2010 Ryan P. Murphy

Answer in you ISN: The next slide has the answers Word Bank: Pinna, Nerves, Stirrup, Ear Canal, Semicircular Canals. These carry electro-chemical signals from the inner ear (the cochlea) to the brain. The tube through which sound travels to the eardrum. The visible part of the outer ear. It collects sound and directs it into the outer ear canal Three loops of fluid-filled tubes that are attached to the cochlea in the inner ear. They help us maintain our sense of balance. A tiny, U-shaped bone that passes vibrations from the stirrup to the cochlea. This is the smallest bone in the human body (it is 0.25 to 0.33 cm long). Copyright © 2010 Ryan P. Murphy

Use Deductive Reasoning. (Frontal Cortex) Word Bank: Pinna, Nerves, Stirrup, Ear Canal, Semicircular Canals. Nerves - These carry electro-chemical signals from the inner ear (the cochlea) to the brain. Ear canal - The tube through which sound travels to the eardrum. Pinna - The visible part of the outer ear. It collects sound and directs it into the outer ear canal Semicircular Canals - Three loops of fluid-filled tubes that are attached to the cochlea in the inner ear. They help us maintain our sense of balance. Stirrup - A tiny, U-shaped bone that passes vibrations from the stirrup to the cochlea. This is the smallest bone in the human body (it is 0.25 to 0.33 cm long). Copyright © 2010 Ryan P. Murphy

Which terms are switched? Answer in your ISN Nerves - These carry electro-chemical signals from the inner ear (the cochlea) to the brain. Stirrup - The tube through which sound travels to the eardrum. Pinna - The visible part of the outer ear. It collects sound and directs it into the outer ear canal Semicircular Canals - Three loops of fluid-filled tubes that are attached to the cochlea in the inner ear. They help us maintain our sense of balance. Ear Canal -A tiny, U-shaped bone that passes vibrations from the stirrup to the cochlea. This is the smallest bone in the human body (it is 0.25 to 0.33 cm long). Anvil :- A tiny bone that passes vibrations from the hammer to the stirrup. Cochlea A spiral-shaped, fluid-filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form. Eardrum (Also called the tympanic membrane) a thin membrane that vibrates when sound waves reach it. Eustachian Canal - A tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside. Hammer A tiny bone that passes vibrations from the eardrum to the anvil.

Which terms are switched? Answer in your ISN Cochlea These carry electro-chemical signals from the inner ear (the cochlea) to the brain. Ear Canal- The tube through which sound travels to the eardrum. Pinna - The visible part of the outer ear. It collects sound and directs it into the outer ear canal Semicircular Canals - Three loops of fluid-filled tubes that are attached to the cochlea in the inner ear. They help us maintain our sense of balance. Stirrup -A tiny, U-shaped bone that passes vibrations from the stirrup to the cochlea. This is the smallest bone in the human body (it is 0.25 to 0.33 cm long). Anvil :- A tiny bone that passes vibrations from the hammer to the stirrup. Nerves - A spiral-shaped, fluid-filled inner ear structure; it is lined with cilia (tiny hairs) that move when vibrated and cause a nerve impulse to form. Eardrum (Also called the tympanic membrane) a thin membrane that vibrates when sound waves reach it. Eustachian Canal - A tube that connects the middle ear to the back of the nose; it equalizes the pressure between the middle ear and the air outside. Hammer A tiny bone that passes vibrations from the eardrum to the anvil.

Video Link! The Human Ear. Take notes in your ISN http://www.youtube.com/watch?v=r-c5GpoD8wI Copyright © 2010 Ryan P. Murphy

Loudness is measured in decibels (dB) – This is the force of sound waves against the ear. The louder the sound, the more decibels. Ticking Watch 20 Whisper 30 Normal Speech 50 Car 60 Alarm Clock 80 Lawn Mower 95 Chain Saw 110 Jackhammer 120 Jet Engine 130 Copyright © 2010 Ryan P. Murphy

Loudness is measured in decibels (dB) – This is the force of sound waves against the ear. The louder the sound, the more decibels. Ticking Watch 20 Whisper 30 Normal Speech 50 Car 60 Alarm Clock 80 Lawn Mower 95 Chain Saw 110 Jackhammer 120 Jet Engine 130 Copyright © 2010 Ryan P. Murphy

Which of the following require ear protection? Loudness is measured in decibels (dB) – This is the force of sound waves against the ear. The louder the sound, the more decibels. Ticking Watch 20 Whisper 30 Normal Speech 50 Car 60 Alarm Clock 80 Lawn Mower 95 Chain Saw 110 Jackhammer 120 Jet Engine 130 Which of the following require ear protection? Copyright © 2010 Ryan P. Murphy

Sounds that are too loud or that last a long time can cause Noise-induced hearing loss (NIHL). Our sensitive hair cells convert sound energy into electrical signals that travel to the brain and can become damaged. Once damaged, our hair cells cannot grow back. Copyright © 2010 Ryan P. Murphy