Pupil Dilation

The Pupil Dilation Response
This experiment may be performed with a partner (with proper social distancing), but the write-up
should be done independently. Your write up should be of your own words and not those of another
person. Do not copy anything from the internet. Any academic dishonesty will result in a zero for your
grade and disciplinary action.
You will need something that makes a brief audible and loud noise (example: cell phone alarm), a
mirror, and a room that you can make completely dark (example: closet or bathroom).
Methods:
Hold the cell phone while standing in the room near the light switch
Ring the bell and immediately turn out the light
Wait in total darkness for 15-20 seconds
Turn the light back on for 15-20 seconds
Ring the bell and immediately turn out the light for 15-20 seconds
Repeat this process 30 times (Yes, THIRTY trials), making sure that each time you ring the bell, the light is
immediately turned off each time
Finally, with the light on and you looking in the mirror closely at your eyes, ring the bell. Your pupils
should dilate slightly even without the change of light.
Write-up:
In a Results/Conclusions of a research article format, explain your findings. ~2 pages APA format
Did you see your pupils dilate? If so, explain in terms of classical conditioning (identify US, UR, CS, CR).
Include a discussion of timing/presentation, quality and salience. Discuss whether your pupils will now
always dilate to the sound of that tone, explain why or why not. Finally, relate how classical
conditioning can influence a person when they see advertisements for food during dinner time or the excitment of cleaning the floors/counters to this procedure and your findings.