This document provides instructions for a psychology lab assignment involving operant conditioning of a virtual rat named Sniffy. Students will train Sniffy to press a bar using five reinforcement schedules and analyze how the schedules affect the persistence of the learned behavior. The schedules include continuous reinforcement as well as fixed ratio, fixed interval, variable ratio, and variable interval partial reinforcement. Students are directed on how to complete the training in the computer program, save their work, answer analysis questions, and submit their records and answers for a grade.

1. Sniffy the Virtual Rat
Psych 210 Winter Lab Assignment

2. Today:
1) The Experiment
2) Operant Conditioning
3) The 5 Reinforcement Schedules we’ll use
4) Steps to completing the assignment
5) Grade Determination

3. The Experiment
 Train Sniffy using Operant Conditioning
 using campus computer program
 Using 5 different Reinforcement Schedules
 Analyze results to determine how choice of reinforcement
schedule affects extinction
 Ultimately asking:
• How do different schedules of reinforcement
affect the persistence of a learned behavior?

4. Operant Conditioning
 Increases the rate of a desired
behavior by reinforcing that
behavior when it occurs
 In our case, we want Sniffy to
bar-press
 We will reinforce with food
pellets
 See Chapter 5 (B.F. Skinner) in
your textbook

5. Operant Vs. Classical Conditioning
Operant (Type R):
 Emphasis is on the
Response
 Use reward to increase a
response
Classical (Type S):
 Emphasis is on the
Stimulus
 Get a stimulus to elicit a
response not normally
paired with it

6. Schedules of Reinforcement-
2 Main Types:
Continuous Reinforcement
(CRF):
 Rewarded every time the
desired behavior occurs
 Every time Sniffy presses
the bar, he will get a food
pellet
Partial Reinforcement
(PRF):
 Rewarded some times
when behavior occurs;
not every time
 e.g. Sniffy might press
the bar 5 times and only
get rewarded once.

7. PRF Schedules-
Types:
Fixed:
 Reward happens after a
set number of responses
 “Fixed Ratio”
OR
 after a set amount of
time passes
 “Fixed Interval”
Variable:
 Reward happens around a
certain average number of
responses
 “Variable Ratio”
OR
 after an average amount of
time passes
 “Variable Interval”

8. Fixed Ratio (FR):
 Set a specific number of responses
required for reward, e.g. 5
 Sniffy will then get a food pellet after he
presses the bar 5 times
 Real Life Example:
Salesperson having to
reach a quota to get
payment

9. Fixed Interval (FI):
 Set a certain number of seconds to
pass before reward is given, e.g. 10
seconds
 Sniffy will be rewarded on his first bar-
press after 10 seconds passes
 Real Life Example:
Employees getting a Christmas Bonus
each year for hard work

10. Variable Ratio (VR):
 Set an average number of responses
needed for reward, e.g. 5
 Sniffy will get rewarded for about 5 bar-
presses- maybe after 4, maybe after 7, etc.
It fluctuates around a certain number.
 Real Life Example:
• VLT machines rewarding
randomly (video lottery
terminal)

11. Variable Interval (VI):
 Set a number of seconds that will need to
pass, on average, before reward, e.g. 15
seconds
 Sniffy will be rewarded when he responds
after about 15 seconds- maybe after 12
seconds, 14, 18, etc.
 Real Life Example:
• Pop quizzes in class that
happen about every
month or so

12. The Computer Program:
 My Computer
 “Apps on Caesar (S: )”
 “Sniffy” Folder
 Double-click “Sniffy” Icon

13. Completing the Assignment:
 Step 1) Observe Sniffy’s behaviors
 Step 2) Magazine Train Sniffy
 Step 3) Train on CRF schedule
 Step 4) Extinguish behavior
 Step 5) Observe Spontaneous Recovery and Extinguish
 Step 6) Train on FR schedule and Extinguish
 Step 7) Train on FI schedule and Extinguish
 Step 8) Train on VR schedule and Extinguish
 Step 9) Train on VI schedule and Extinguish

14. Saving your Progress:
 Saving properly is IMPORTANT for this lab!
 THINK about what and how you are Saving each time
 Always save to your H: Drive
 Manual tells you when to Save and when to Print
 As you are progressing through one step, save over
the same file. So, throughout CRF training, keep
saving as “CRF”. Once done, do NOT overwrite again.

15. Saving your Progress:
 You should save and print these files as you go:
 “CRF” (documents Steps 1-3) – DO NOT SAVE OVER THIS FILE ONCE
DONE THE ORIGINAL TRAINING!
 “CRFext” (documents Steps 1-5) –*Print this*
 “FR” (documents Step 6 –Training)
 “FRext” (documents Steps 6- Training and Extinction) –*Print this*
 “FI”, and then “FIext” (Step 7) -*Print this*
 “VR”, and then “VRext” (Step 8) - *Print this*
 “VI” and then “VIext” (Step 9) -*Print this*

16. You Submit:
 Assignment is due the week of April 2nd
 As you go through the Steps, your manual instructs you
to record certain observations
 You will use these, and Ch. 5, to answer the questions
attached at end of manual
 Submit these answers, typed and in APA format
 Also, submit the Records you have Printed out as an
Appendix
*See directions on this in Manual*

17. Grade Determination:
Questions: 5.5%
Printed Records: 2%
Participation: 5%
Total: 12.5%

18. Passing in the Lab:
There will be lab every week up until:
 Mar. 26th- 30th: NO LABS
 Work independently if you need to catch up
 Apr. 2nd -6th: NO LABS
 Pass in the assignment to the Annex
 My office 114F, or the Drop Box in Main Hallway

19. Starting Today:
 Read through your manual
 Start on steps 1 and 2
 Observe Sniffy’s behavior and get him Magazine
Trained
 Before you leave, save your work as ‘CRF’
 Use the drop-down arrow in the “Save” window to save
to your H: drive