PSY 1001 1st Edition Lecture 10 Outline of Last Lecture I Learning American Style II Skinner s Operant Conditioning A Reinforcement B Punishment C Schedules or reinforcement Outline of Current Lecture I How do we experience sensory input A Sensation B Perception C Transduction D Sensory Adaptation E Psychophysics II Vision A Sensory Organ Eye B Color Perception 1 Trichromatic Theory 2 Opponent Process Theory These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute C Basic Visual Pathways D Problems with Vision E Perception 1 Bottom up Top down processing 2 Perceptual hypotheses 3 Motion perception 4 Depth perception Current Lecture I How do we experience sensory input A Sensation is the detection of physical energy by our sense organs which send that information to the brain B Perception is the brain s interpretation of raw sensory data C Transduction 1 The external stimulus is converted by a sense receptor into neural activity via transduction D Sensory Adaptation 1 Activation is highest when stimulus is first detected then sensory adaptation occurs E Psychophysics study of how we perceive sensory stimuli based on their physical characteristics 1 Absolute threshold is the lowest level of a stimulus we can detect 50 of the time a A single candle 30 miles away b 50 odorant molecules 2 The just noticeable difference is the smallest amount of stimulus change we can detect 3 Weber s law the stronger the stimulus the greater the change necessary for the detection of a difference 4 II Signal Detection Theory Vision A Sensory Organ Eye 1 Light a The human visible spectrum is a narrow band of light that we respond to b Other animals may have a more restricted or broader spectrum B Color Perception 1 Trichromatic Theory color vision is based on our sensitivity to three primary colors a Consistent with three types of cones in eyes b Explains color blindness 2 Opponent Process Theory color vision as a function of complementary opposing colors red vs green or blue vs yellow C Basic Visual Pathways 1 Different cortical cells respond maximally to different types of stimuli 2 Feature detector cells allow us to detect lines and edges a Simple cells detect orientation specific slits of light in a particular location b Complex cells also orientation specific but less dependent on location than simple cells