Journal 3

• What is the difference between bottom-up processing and top-down processing?

  Bottom-up processing refers to simply taking in information, top-down processing interprets information and recognizes patterns based on prior knowledge
• sensation


  detection of external stimuli via five senses, this information gets transported to the brain
• perception


  organizing and interpreting sensory information
• transduction

  conversion of sensory input to electrical impulses which goes to the brain for processing
• absolute threshold

  weakest amount of stimuli a person can detect 50 % of the time
• difference threshold


  minimum amount something needs to change before somene detects it
• weber's law


  for the average person to perceive a difference, two stimuli must differ by a constant percent
• sensory adaptation


  getting used to stimuli after constant exposure
• wavelength


  the distance from one wave peak to the next.
• The wavelength of light determines its color
• Cones in the eyes detect color & fine detail
• Rods detect black & white as well as peripheral motion
• The optic nerve connects the eyes and the brain
• Compare and contrast RODS/CONES


  RODS detect black and white and peripheral vision; cones detect color and fine detail
• gate control theory


  Pain is blocked by a gate on the spinal cord, eg rubbing wounds post injury
• olfaction


  olfactory receptors alert brain of smell via axon fibers
• kinesthesia


  sensing movement within the body
• vestibular sense

  monitors head's position and judges distance
• Phantom Limb


  The sensation that a missing or amputated limb is still attached
• Pheromones produce chemical messengers for the olfactory system
• Selective Attention


  Focusing your awareness on one particular task or stimulus
• cocktail party effect


  honing in on one auditory sound, the ability to filter out other sounds.
• Listening to someone's voice in a loud cafeteria is an example of the cocktail party effect
• Change blindness is a form of inattentional blindness
• Change Blindness


  failing to notice changes in the environment because your attention is directed elsewhere
• This is an example of perceptual set

  
• perceptual set


  our tendency to perceive one thing and not another based on experience and expectations
• The four gestalt principles are proximity, similarity, figure-ground, and closure
• Similarity is grouping like objects together during perception
• Proximity is grouping close objects together during perception
• this is an example of binocular cues

  
• Shape and size constancy are both forms of perceptual constancy
• Shape constancy


  we perceive familiar objects as constant even while our retinas receive changing images of them
• Size constancy


  we perceive objects as having a constant size, even while our distance from them varies