Sensation and Perception

Preassement to Sensation and Perception

Question 1  You can see color in your peripheral vision

 FALSE

Question 2  Receptor cells allow you interpret what is going on your world

 TRUE

Question 3  Sensation refers to the process of getting information from the world to our brain.

 TRUE

Question 4  If you stay in a hot tub it will seem as hot as it did when you first got in it. Sensory adaptation refers to the decline in sensitivity to a constant stimuli.

 FALSE

Question 5  Our interpretations of the world are due to our personal sensations.

 FALSE

Question 6  The colored part of the eye, which is actually a ring of muscles that controls the size of the pupil, is called the iris

 TRUE

Question 7  The eardrum is interprets sound waves for the brain so that we can hear.

 FALSE

Question 8  People judge people based on what groups they belong

 TRUE

Question 9  On a clear, dark night we can see a candle flame 30 miles away.

 TRUE

Question 10  Advertisers are able to shape our buying habits through subliminal messages

 FALSE

Question 11  If we stare at a green square for a while and then look at a white sheet of paper, we can see red

 TRUE

Question 12  If we close our eyes and hold our nose, we cannot taste the difference between an apple and a raw potato.

 TRUE

Question 13  If required to look through a pair of glasses that turns the world upside down, we soon adapt and coordinate our movements without difficulty.

 TRUE

Question 14  If people are told that an infant is “David”, they are likely to see “him” as bigger and stronger that if the same infant is called “Diana.”

 TRUE

Question 15  Laboratory evidence clearly indicates that some people do have ESP

 FALSE

Our Essential Questions! Our Essential Questions!  How do sensations and perceptions differ?  How do the senses transform information into brain messages?  What is the nature of attention?

Grab a scrap sheet of paper   Write down your definition of   sensation   perception

Let’s brainstorm…  SensationPerception

Sensation  The process by which our sensory systems (eyes, ears, and other sensory organs) and nervous system receive stimuli from the environment  A person’s awareness of the world

Perception  The process of integrating, organizing and interpreting sensations.

Bottom-Up Processing  Information processing that focuses on the raw material entering through the eyes, ears, and other organs of sensation

Top-Down Processing  Top-Down Processing: expectations and experiences influence how we interpret incoming sensory information expectations and experiences influence how we interpret incoming sensory information

Sensation v Perception  Complete the worksheet

The Major Senses  7 major senses Vision (most studied) Vision (most studied) Hearing Hearing Touch Touch Smell Smell Taste Taste Vestibular Vestibular Kinesthetic Kinesthetic

 2i-_8

The Riddle of Separate Sensations  Sense receptors specialized cells unique to each sense organ that respond to a particular form of sensory stimulation specialized cells unique to each sense organ that respond to a particular form of sensory stimulation

Sensory Receptors – An Example  When you bite into a crisp apple, you hear the crunch, you taste the sweetness, you feel the smooth skin, you see the red, and you smell the aroma.

Receptor Cells  Each of the seven senses is specifically coded to only take in one type of stimulus, whether it be light waves, sound waves, smell, taste, or touch.

What Does That Mean?  Turn to your neighbor and tell them what sensation means.  What is with those blasted receptor cells as well… explain what they do

Principles of Sensation   Transduction   Absolute threshold   Difference threshold   Sensory adaptation

Transduction  The process by which a form of physical energy is converted into a coded neural signal that can be processed by the nervous system.

What is a Threshold?

Threshold  An edge or a boundary  Walking into the room – on one side you are in the room on the other you are outside of the room

Absolute Threshold  The smallest possible strength of a stimulus that can be detected half the time.

Absolute Threshold Example (1)  Taste: 1 gram of table salt in 500 liters of water – the minimum needed to taste something

Absolute Threshold (2)  Vision:A candle flame on a clear night, 30 miles away – the minimum needed to see it. Doesn’t mean that you can make out what it is

Just Noticeable Difference Threshold  The minimum difference that a person can detect between two stimuli 50% of the time.

Examples  When you can detect the difference in volume of music  When you can detect the difference in pressure on your arm

Weber’s Law  The greater the magnitude of the stimulus, the larger the difference must be in order to be noticed

Weber’s Law Example  If you are carrying 20 lbs. and add 5 lbs., it’s noticeable. If you are carrying 100 pounds and add 5 pounds, it may not be noticeable. You need to add 10 lbs. to 100 pounds to make it noticeable.

Weber’s Law Lab In groups of 3, follow the directions and complete the lab

Sensory Adaptation  When exposed to a stimuli over a period of time there will be a diminished sensitivity to it  If a stimulus is constant and unchanging, eventually a person may fail to respond to it

Example of Sensory Adaptation  A hot tub – after a certain period of time no longer seems as hot

The Nature of Attention  Where does attention come into play here?

Hypothetical Situation  What would happen if we had no filter between sensation and perception?”  Hallway example

Sensory Overload  Overstimulation of the senses

Selective hearing  Do you think it exists?

Selective Attention  Focusing conscious awareness on a particular stimulus (sense) to the exclusion of others

Selective Attention Examples  Walking down the hallway – all 5 senses are firing. What grabs your attention?

Let’s write!  How do sensations and perceptions differ?  How do the senses transform information into brain messages?  What is attention? How much control do we have over our attention?

Time to get creative!  With your partner, create a poster depicting 3 the following: Sensation Sensation Perception Perception Attention Attention Absolute sensory thresholds Absolute sensory thresholds Sensory overload Sensory overload

 hkBg