Sensory Adaptation

Sensory Adaptation• Diminished sensitivity as a result of constant stimulation• If a stimulus is constant and unchanging, eventually a

person may fail to respond to it• Move your watch up your wrist an inch or put your ring on

a different finger. You will feel it at first but later you won’t notice it. Your senses have adapted to it.

• This is why the lake water is cold at first but you “get used to it.”

• Also why you don’t feel your glasses on your nose or your clothes on your body.

• Remember the displacement goggles experiment from class. This showed motor adaptation to a change in vision.

Selective Attention

Selective Attention• Focusing conscious awareness on a

particular stimulus to the exclusion of others

• The ability to focus on one stimulus at a time

• Allows a person to function in a world filled with many stimuli

• People with ADD have trouble doing this.

Read the following words to yourself

•Did you notice that the word “the” was written twice?

•If not, it shows how your brain was selectively paying attention to the meaning of what you were reading and not what was actually written.

Read the following words to yourself

•Did you notice that the word “the” was written twice?

•If not, it shows how your brain was selectively paying attention to the meaning of what you were reading and not what was actually written.

Selective Attention: An Example• View this updated version of Neisser’s Selective

Attention Test basketball video clip below. Count the number of passes made by the girls in white. (click HERE to start)

Did you notice the lady walk across the room with the umbrella? No! You were too busy watching & counting the

passes. Try these: http://www.dothetest.co.uk/

Cocktail Party Effect

• Demonstrates selective attention• If talking to one person in a crowded noisy room

you will still notice if someone says your name.• This demonstrates that even though you weren’t

paying attention to something your brain was still monitoring other sensual information in the room and alerting you when there was something you needed to pay attention to.