Transcript Chapter 4 - Sensation and Perception

Chapter 4
Sensation and
Perception
You Tube: Hallucination
video
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Sensation – process of receiving information
from the environment.
Adaptation – allows us to filter meaningless
stimuli out.
Perception – process of organizing sensory info
to make it meaningful.
Demonstrations – 4x4 Squares; Eye Dropper
A) Sensation – dominated by vision.
1) Sight – light is broken down from white
(origin-sun) to wavelengths/frequencies.
 Evidence suggests that other senses will
compensate partly for sight loss.
Explore PCS
 Over time, as our lens becomes less
flexible, focusing on objects gets
tougher….thus eyeglasses.
 Afterimages (p97)
2) Hearing – comes in the form of sound
waves. Humans lag behind some animals in
use of sound. (Dolphin, Dog)
• Measured intensity (loudness) is
through the Decibal.
Test Your Sense of Pitch
You will hear a number of well-known tunes. Some will be played
correctly, while others will be played incorrectly (with some wrong
notes). Your task is to decide whether the tunes are played
correctly or incorrectly.
Here's an example to show you the kind of thing to expect. Click
the link below that says "Play example tune." A music player will
load on a new page and begin playing the tune. When it finishes,
use your browser's Back button to return to the quiz.
http://www.nidcd.nih.gov/tunetest/pages/dtt.aspx
After taking the test you can see if you can hear pitch or not.
3) Touch – “Cutaneous” senses, based on
three types of receptors:
a) Pressure Report
b) Temperature Report
c) Injury/Poison Report…ugh
Demo. Touch Threshold - toothpicks
4) Smell – olfaction; powerful in humans
when involved in emotional events.
Ex. Cotton Candy….others?
Our most animal-like, though we lag here in
this area as well.
 Pheremones – odor chemicals emitted by the
body. Designed to “reach” a partner.
 Do we have these?
5) Taste – from receptors called “Buds.” Four
types: salt, sweet, sour, bitter.
• “Need” for sugar/salt based on physical
demand (pregnancy tastes, etc.) for balance.
• “Detectors” of bitter and sour also natural
(poison, spoiled food)
• Connection to vision and
Appearance (p105)
B) Perception – The way we “see”
things.
1) Size Constancy – the ability to maintain
the size of an object regardless of distance
from you. Ex. Moon/Thumb
Ex. ants/skyscrapers.
• Size and maturity of people is a factor
• Color, Shape, Space, Brightness also.
2) Depth Perception – ability to see the
relation of objects in space. Inherent very
early in life…see text “baby cliff.”
Ex. All thumbs p.109
Dog Depth Perception FAIL
Adaptability of Senses