Upload
colin-simon-long
View
213
Download
0
Embed Size (px)
Citation preview
Monday, October 18th, 2010Objective: Develop an understanding of our senses
review of where we are going this unit What is Sensation and Perception View a movie to review where we are going
Do Now: Write down our senses and each one’s purpose What do you think sensation and perception mean? Hand in your Project!
Sensation – what occurs when a stimulus activates a receptor
Perception – the organization of sensory information into meaningful experiences
Sensation and Perception Sensation and Perception
• Sensory processing and adaptation• Vision• The Other Senses:
Hearing Touch Taste Smell
• Perception• Subliminal Messages• What is real?
Tuesday, October 19th
Today’s Goals discussion of our senses discuss terms used in discussing our sensations Experiment to understand absolute threshold
Do Now•What are our 6 senses?
Homework•Evaluating our senses
How many senses do we have?
The five we always remember, but we really do have a 6th sense….not seeing dead people, but our sense of balance.
What is the difference?
Sensation Perception
Absolute Threshold The weakest amount of a stimulus necessary to
produce a sensation 50% of the time.
sight Candle flame 30 miles away
hearing Ticking 20 feet away
taste Tsp sugar in 2 gallons water
smell 1 drop of perfume in a house
touch Bees wing falling a distance of one centimeter
Difference Threshold
The smallest change in a physical stimulus that can be noticed half the time.
Do you notice another book in your bag if you already have 5 in it?
Signal detection theory
Study of people’s tendencies to make correct judgments in detecting the presence of stimuli. Combines concept of ability to detect with one’s own judgments.
?????????????????
EXAMPLES OF THE SIGNAL DETECTION THEORYThe Classic Radar Operator Example
The Shower/Phone Example The Eye Exam
Signal: Are there actually enemy aircraft indicated on the radar screen?
Yes No
Decision: are they enemy Aircraft?
Yes Hit False Alarm
No Miss Correct Rejection
Weber’s Law
The larger or stronger a stimulus, the larger the change required for a person to notice that anything has happened to it.
This increase in a stimulus need to produce a just-noticable difference is constant:
dR = C * R "equal relative increments of stimuli are
proportional to equal increments of sensation."
Is the Room too Dark? Well, to see the SAME level of improvement…
1 candle x 10 = 10 candles 10 candles x 10 = 100 candles And for the same improvement again, 100 candles x 10 = 1000 candles!
EXPERIMENT TIME!
Also, handout homework – rank your senses
Why are we doing this?
Rationale – Psychology is often considered a “hard” (versus “easy” science) because of the complexity of measuring concept of interest. Although one would think that physical stimuli would be easily measured, psychological reaction to a stimuli is not so easily measured. Today, we will evaluate the concept of absolute threshold in order to understand why this is so hard to precisely determine, as well as to further understand how one studies sensation and perception.
To determine absolute threshold of the sugar water using two different methods
Method of limits – using ascending on descending order Method of Constant Stimuli – using
Procedure
Break into groups of four subject (blindfolded) Experimenter (hands water to subject) Recorder (Puts results on the worksheet) Math wiz (averages a chart)
Supplies blindfold 10 small cups (labeled 1-10) Fill each small cup with samples from the larger cups. calculator
Procedure 1 (method of limits) – give subject sips in ascending and descending 4 times; average and report mean. Record response of subject.
Procedure 2 – Give sips according to preset random order. Record responses
Finish any final calculations and report results
Period 1
Group 1 Group 2 Group 3 Group 4 Group 5
Limits threshold (mean)
Constant Stimuli threshold
Period 9
Group 1 Group 2 Group 3 Group 4 Group 5
Limits threshold (mean)
Constant Stimuli threshold