Process in which a sense organ changes, or transforms, physical energy into electrical signals that become neural impulses, which may be sent to the brain for processing
Ex: Skunk spray send electrical signal to brain
Decreasing response of the sense organs, the more they are exposed to a continuous level of stimulation
Ex: Wearing jewelry or glasses for a period of time and getting use to it
Relatively meaningless bits of information that results when the brain processes electrical signals that come from the sense organs
Meaningful sensory experiences that result after the brain combines hundreds of sensations
Invisible - too short
Gamma rays, X rays, and Ultraviolet rays
Visible - just right
One particular segment of electromagnetic energy that we can see because these waves are the right length to stimulate receptors in the eye
Invisible - too long
Radio and television
Structure and Function
Eyes perform two separate process.
1st) eyes gather and focus light waves into a precise area at the back of your eyes.
2nd) area absorbs and transforms light waves into impulses, a process known as transduction
back of the eye the image is upside down. Somehow the brain turns the image rightside up
The problem with light waves is that after they strike an object, they are reflected back in a broad beam
Rounded, transparent covering over the front of your eye
round opening at the front of your eye that allows light waves to pass into the eye's interior
Circular muscle that surrounds the pupil and controls the amount of light entering the eye
Transparent, oval structure whose curved surface bends and focuses light waves into an een narrower beam
located in the very back of the eyeball. Is a thin film that contains cells that are extremely sensitive to light.
Lightsensitive cells, called photorecptors, begin the process of transduction by absorbing light waves
3 layers of the retina
back layer contains two kinds of photoreceptors that begin the process of transduction, changing light waves into electrical signals. One kind of photorecptor with a rodlike shpae is called a rod and is located primarily in the periphery of the retina. The other photoreceptor with a conelike shape is called a cone and is located primarily in the center of the retina in an area called the fovea
photorecptors that contain a single chemical, called rhodopsin which activated by small amounts of light. Extremely light sensitie, allow us to see in dim light, only see black, white, and shades of gray
photoreceptors that contain three chemicals called opsins which are activated in bright light and allow us to see color. Cones are wired individually to neighboring cells. allow us to see fine details.
Nerve impulses flow through the optic nerve as it exits from the back of the eye. Exit point create a blind spot
The optic nerves partially cross over and make a major stop in the Thalamus, which does some initial processing. The thalamus relays the impulses to the back of the occipital lobe in the right and left hemispheres.
Primary Visual Cortex
Back of each occipitl lobe lies a primary visual cortex, which transforms nerves impulses into simple visual sensation, such as texture, lines, and colors.
primary visual cortex sends simple isual sensations to neighboring assocations areas, which add meaning.
Part of your visual association area were damaged.
Is difficulty in assembling simple visual sensation into more complex, meaningful images