04/09/14 Unit V

• Sensation and Perception
• Sensation- Your window to the world.
• Perception- Interpreting what comes into your window.
• Sensations
• The process by which our sensory receptors and nervous system receive stimulus from the environment.
• Bottom- Up V. Top- Down Processing
• Begins with recess receptors and works up to the brains integration of sensory information. 
• Information processing guided bu higher level mental process. 

• Absolute Threshold
• The minimum stimulation needed o detect a stimulus 50% of the time.
• Difference Threshold
• The minimum difference that a person can detect between stimuli.
• Also known as just noticeable difference.
• Weber's Law
• The idea that to perceive a difference between two stimuli; they must differ by a constant percentage, not a constant amount.
• Signal Detection Theory
• Predicts how we detect a stimulus amid other stimuli.
• Assumes that we do not have an absolute threshold.
• Sensory Adaptation
• Decreased responsiveness to stimuli due to constant stimulation.
• Selective Attention
• The focusing of conscious awareness on a particular stimuli.
• Cocktail- Party Phenomenon
• The cocktail party effect describes the ability to focus one's listening attention on a single talker among a mixture of conversations and background noises, ignoring other conversations.
• Form selective attention.

• Vision
• Our most dominating sense
• Visual Capture
• Phase 1: Gathering Light
• Short Wavelength: High frequency (bluish colors, high pitched sounds.)
• Long Wavelength: low frequency (reddish colors, low pitched sounds.)
• The height of a wavelength gives us it's intensity (brightness)
• The length of the wave gives us it's hue (color)
• The longer the wave the more red
• The shorter the wavelength
• Transduction
• Transmitting signals into neutral impulses 
• Information goes from the senses to the thalamus, then to the various areas in the brain.
• Transduction- Conversion of the form of energy to another.
• How is this important when studying sensation?
• Stimulus energies to review impulses
• Ex: Light energy to vision.