1. Sensation and Perception By Cliff Ridenour

2. Thresholds Thresholds can be divided into “detection thresholds” and “discrimination thresholds” Detection is the act of sensing a stimulus such as through sound pressure, taste, ect. Absolute threshold is found through experiments with detection

3. Second type of threshold Discrimination threshold Ability to distinguish between two stimuli The minimum amount of distance between two stimuli is the “just noticeable difference (JND) Weber’s Law- the greater the magnitude of the stimulus, the larger the differences must be to be noticed

4. Sensory mechanisms Sensory coding Process by which receptors convey information to the brain Everything is interpreted psychologically by the brain Single cell recording A technique by which the firing rate and pattern of a single response cell can be measured

5. Visual sensation Eye receives light from input by a complicated process… Light passes through cornea~ lens bends to focus image~ retina at the back of the eye is covered with rods and cones which detect the light~ passes to bipolar and amacrine cells~ travels through ganglion cells of optic nerve~ optic nerves cross at the optic chiasma and send half of the info. to same side of the brain and half to opposite side~ brain processes.

6. Auditory sensation Auditory input in the form of sound waves~ enter middle ear and vibrate tympanic membrane~ membrane buts up against the ossicles~last of three ossicles is the stapes which vibrates against an oval window~ vibrate cochlea which contains receptor cells located in structures called the basilar membrane~ then to the brain! (kinda)

7. Touch Cutaneous and tactile receptors that provide info. about pressure, pain, and temp. Reception of stimulus goes to nerves then up to brain for processing Warm fibers and cold fibers respond to temperature stimuli and are self explanatory

8. Sensory Adaptation Adaptation is a temporary unconscious change in response to environmental stimuli. Habituation is the process of becoming accustomed to a stimulus and noticing it less over time. Dishabituation is when a change in the stimulus causes us to notice it again.

9. ATTENTION!!!!!!!!!!!! Attention refers to the processing through cognition of select portions of the massive amount of stimuli coming in at any given time. Selective attention is attending to one thing, while ignoring others. Divided attention = multi tasking!

10. Perceptual processes How we interpret stimuli Bottom-up processing achieves recognition of an abject by breaking it down into it’s components. Top down processing is immediate recognition, which is faster, but can cause misconceptions.