Good Morning! WARM UP: How does light become a visual image? Draw out the path light takes from the world around us into our eyes and through the brain. Be sure to mark each part of the eye that the light travels through.

Sound and Hearing What?

What is Sound? All sounds are vibrations moving through the air around us Any action that causes sound moves air around (Displacement) That movement is what causes the vibrations that our ears interpret as sound. Quick Question: Can we see sound?

Answer: What happened here? https://www.youtube.com/watch?v=KC7zdZ00eZ4 What happened here? Can you think of any other examples of when we would “see” sound?

What does sound look like? If we were to put a sound wave into visual form, it would look like this: Wavelength determines pitch (high or low) Amplitude determines volume

So how do we hear?

Step 1: Sound moves down ear canal and vibrates Ear Drum

Step Two: Eardrum vibrates Malleus (Hammer)

Step Three: Malleus hits Incus (Anvil)

Step Four: Incus vibrates against Stapes (Stirrup)

Step Five: Stapes vibrates against Cochlea

Step Six: Cochlea translates vibrations into electrical signals

Step Seven: Signals are sent off to the brain down Auditory nerves

Deafness Two main types of Deafness Conductive Deafness: Problems with middle ear Unable to fully amplify sound, cannot hear sounds under a certain volume Hearing aids can assist in this

Sensorineural Deafness: Cannot hear sounds at certain frequencies (Pitch) Damage to the inner ear Harder to treat, Cochlear implants have come along to help with this. But if Auditory nerves are damaged, they are ineffective Can be through disease, but most damage comes from prolonged exposure to loud noises.

How do we figure out where sound comes from? When we hear something and are trying to determine where it came from, our brain starts asking several questions: Which ear is hearing more noise? If one is hearing more than the other, look that way. If they are the same, then it’s either ahead of us or behind us. Have we heard this sound before? For example, if we hear a plane overhead, we know to look up into the sky

Echolocation: https://www.youtube.com/watch?v=A8lztr1tu4o

Quick Review: Draw out and label a map of the ear Draw out a sound wave List each step in the hearing process and label it on the map Review: Which lobe processes auditory inputs?

Sound Location Lab: Break into groups of ~5 Have one representative from each group get a copy of the lab sheet, write each group members name on the sheet. Follow procedures, repeat step two only once Record each group members’ results on the back of the sheet Answer the other two questions in the results section.

Music Listening activity Remember that none of our senses act independently. When one is triggered, it usually gains a reaction from the other senses. Let’s listen to this song first. Write down any images or feelings that come to mind Then we will watch the video that accompanies it Did your images line up at all?