1. Sensation

2. Sensation
Information coming into our brain from our sensory receivers

3. Scientific Names for the Six Senses
Seeing: Visual
Hearing: Auditory
Tasting: Gustatory
Smelling: Olfactory
Sense of Touch: Tactile
Balance: Vestibular

4. Bottom-up Processing
Analysis of the stimulus begins with the sensory receptors and works up to the level of the brain and mind.
Letter “A” is really a black blotch broken down into features by the brain that we perceive as an “A.”

5. THE CHT Top-Down Processing
Information processing guided by higher-level mental processes as we construct perceptions, drawing on our experience and expectations.
Top Down Processing explains how our expectations and prior experiences guide our perceptions.
THE CHT

6. Top-Down Processing
Aoccdrnig to rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoetnt tihng is taht the frist and lsat ltteer be at the rghit pclae. The rset can be a total mses and you can sitll raed it wouthit a porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.

7. Making Sense of Complexity
JULIE
“The Forest Has Eyes,” Bev Doolittle
How many faces do you see?

8. Psychophysics Light - brightness Sound - volume Pressure - weight
Psychophysics: study of the relationship between physical characteristics of stimuli and our psychological experience of them
Light - brightness
Sound - volume
Pressure - weight
Taste - sweetness

9. Absolute Threshold Subliminal Messages Thresholds
Minimum stimulation needed to detect a particular stimulus 50% of the time.
Subliminal Messages
Messages presented below absolute thresholds – not consciously perceived

10. “Subliminal Messages”
Some have argued that humans still “pick up” these messages that influence our “unconscious.” Do these messages have suggestive powers?
Skeptics argue “Subliminal Messages” are heavily influenced by top down processes.
Example: Feeling “hungry” during subliminal advertisements.

11. Difference Threshold
Amount of change needed to notice that a change has occurred.
Weber’s Law: The greater or stronger the stimulus, the greater the change required to notice that a change has occurred. The two stimuli must differ by a constant minimum percentage (rather than a constant amount), to be perceived as different.

12. Sensation: Thresholds
Signal Detection Theory: predicts how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise)
Assumes that there is no single absolute threshold because the idea of a threshold ignores the decision- making ability of the test subject.

13. Sensory Adaptation
Diminished sensitivity as a consequence of constant stimulation.
Preview Question 3: What function does sensory adaptation serve?
Put a band aid on your arm and after awhile
you don’t sense it.