Fletcher's+Presentation

Hi my name is Fletcher I'm learning about hearing.

The inter ear is called the cochlea because it's shaped like a shell. The sound is now tiny vibrations that go around the cochlea triggering nerve ending in the brains auditory cortex. When your Mum say's you're not listening to me, she means that my brain is ignoring the sound of her voice that I have heard perfectly well in my ear.

Eyesight

With our brain the eye is just a camera that turns light into electrical nerve impulses. These are carried to the brain area that is called the visual cortex.The front of the eye traps the light. Lenses focus the light into nerve cells at the back of the eye. The retina is where the light is processed into electrical nerve impulses. Light receptors{rods and cones} fire electrical impulses down the optic nerve when they sense light, bright coloured light and dim light. The eye turns light into nerve impulses which is processed by the visual centre in the brain called the visual cortex. This is where we see.

People are short- sighted when the light doesn't focus properly onto the back of the eye.