This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Psychology Notes Section 2 SENSATION AND PERCEPTION Difference between sensation and perception Sensation is the process by which a stimulated receptor produces a neural message. Sensation is the initial stimulation while perception is how you perceive that stimulation. Sensory stimulus from some area in the periphery that travels to the brain. Transduction- the sensory process that converts physical energy in the external • environment into neural messages. Perception- mental process that assigns meaning of the sensory matter • Interpretation of sensation Five senses o Sight/Vision o Hearing/Audition o Smell/Olfaction o Touch/Sensation o Taste/Gustation Sixth sense? • Combination of touch and sound • Balance/Proprioception ♦ Understanding of where our body is on any spatial plane (sitting, standing, moving) Sense organs o Eye o Ear o Nose o Skin o Tongue VIDEO NOTES The Brain Vision • Vision is one of the most important senses ♦ Eyes don’t see they are just sensors Beam information to be deciphered and reassembled by at least 3 million brain cells ♦ In most vertebrates Every waking second the eyes send a billion items to the brain ♦ The Visual Pathway o Lenses of our eyes turn everything upside down o The visual information is beamed across the heavy fibers of the optic nerve o First bend in the pathway is called the optic chiasm Where some of the information from the left and right eyes criss-cross Information then reaches the back of the head Primary Visual Cortex (aka Striate Cortex) • Where visual information begins its processing ♦ At the University of California at Berkley A team of scientists gave monkeys minute quantities of radioactive sugar to see what cells are most responsive in the primary visual cortex. There is precision in way individual nerve cells fire in response to what the eyes see. ♦ Dr. Hubel of Harvard • Primary Visual Cortex A plate of cells a couple of millimeters thick Layered structure About the size of a credit card • Black dot on a screen produced a response from a cat • Some nerve cells are sensitive the spatialties of life ♦ Spatial frequencies • Make clear images that are sustained by a vibration of color & light • Impressionist painters thought that such spatial frequencies might help create and enrich imagery. Perception • Dr. Mortimer Mishkin ♦ Striate cortex sends information forward along two different pathways Top part of the brain to the parietal lobe Bottom part of the brain to the ventral part of the temporal lobe Explains what objects are Helps orient one object from another Grandmother cells (1950s) • Single cell that lit up when grandmothers came into view • Every person had a cell as a representation of that person • Cells only fire if face is at the right angle and not is distorted Cumulative cells is the formal name for grandmother cells...
View Full Document
- Spring '08
- Psychology, visual cortex