1. Lab 6: Measuring Intoxication
UW Biology of Addiction

2. Learning Targets for Lab 6
To learn how intoxication is quantified and observed.
To learn how behavioral response is influenced by environmental factors.
To understand specific types of intoxication, as well as symptoms.
To understand the difference between subjective judgment and objective measurement.
Hypothesis/Claim
IF subject is tested with both subjective and objective methods of impairment judgement, objective measurements provide the best evidence of impairment.

3. Materials Vision Disc (HGN test) Drunk goggles(Reaction Time) Timer
Meter stick (Reaction Time)
Blue Tape Line
Stroop cards- Level 2 & 3
Walk and Turn Instructions
One Leg Stand Instructions

4. Model I
Q1: Was the subject intoxicated? What were the signs. What IS intoxication?
A1: your response

5. Model II
IMPORTANT – read these instructions all the way through before we will proceed to the video.
You will be asked to pause the video prior to its conclusion.
This video takes you (rather a woman suspected of driving drunk) the three National Highway Transportation Safety Association’s (NHTSA) approved Field Sobriety tests.
STOP the 3:30 … she will be in the middle of the one-leg stand test.
Q2 Would you pass or fail this woman? Support your answer.
A2:

6. Model III Answer the following in your lab journal:
Answer the following in your lab journal:
Q3a– After watching this video consider what makes this experiment “scientific”.
A3a:
Q3b – How might you modify the NHTSA tests to make them more “scientific”?
A3b:
Q3c – What are some benefits to performing a more “scientific” experiment? I’m open-minded, what are some disadvantages to being “scientific” in this context?
A3c:
Q3d- How does intoxication effect the response? (at the end of the lab)

7. PART I: FIELD SOBRIETY TESTS
For this the lab, you will work in pairs: One person is the subject, the other is the tester.
You might want to switch notebooks with your partner. That way, the tester can record the subject’s data in her own notebook.
For each test there will be sufficient time for you to EACH have a chance to be the subject.

8. A) Horizontal Gaze Nystagmus (HGN)
The HGN is a test that examines a potentially intoxicated subject for his ability to smoothly track an object moving in his visual field.
An officer has the subject hold his head steady and follow the movements of the object while the officer watches the subject’s eyes.

9. A) Horizontal Gaze Nystagmus (HGN)
The officer is looking for the position at which the subject is unable to smoothly swing the angle of his eye to follow the object (nystagmus means eye jerk).
Look at the diagram, noting the alignment of vision disc.
You can measure this angle by noting the angle at which the eye twitch occurs as displayed by vision discs.
Be sure to record your nystagmus angle in your journal. (Data Table coming up)

10. B) The one-leg-stand test (OLS)
Q4 – You’ve seen the one-leg stand test performed. Why would an intoxicated person perform poorly? Think of at least 3 reasons.
A4:
The instructions for this test are available ONLY for the person role- playing the officer. The subject must do as instructed by the “officer”.
Record your “grade” for the one-leg-stand in the space provided

11. C) Walk-and-turn test (WAT)
Again: only the OFFICER can see/read the instructions for the Walk- and-turn test
Answer the following questions in your lab journal
Q5a – In addition to your previous ideas, come up with one NEW reason for failing this test. Is this test more or less difficult than the one-leg stand?
A5a:
Q5b – How might the officer who is performing the test influence the outcome?
A5b-
Be sure to record your score on the following data table

12. Data Table for Part I Test Your Score
Would you be under suspicion of DUI?
HGN
WAT /7
OLS /4

13. D) Other test we WON’T perform (“non-standard tests”)
Some states use other tests to measure sobriety, but these are poorly supported by scientific studies and are not supported by the NHTSA.
These include:
finger-to-nose test
counting test (counting backward by threes, for instance)
Reciting the alphabet without singing or backwords

14. D) Other test we WON’T perform (“non-standard tests”)
The finger-to-nose test is a test for your sense of proprioception.
Proprioception= your ability to determine where your body parts are in space relative to the other parts.
Not influenced by alcohol in the way that balance is
Does require cognitive processing in order to act appropriately upon signals from the sensory cells
Counting and alphabet tests are merely tests of computation, recitation and memory

15. D) Other test we WON’T perform (“non-standard tests”)
Answer the following in your journal: Q6 – A counting and alphabet test can allow one to analyze cognitive functioning. Why are they not recommended tests? A6: Q7 – Rethink your definition of “intoxication” (question 1). Do the tests you just completed test for ANY type of intoxication? A7:

16. Part II: Research Lab Tests for Intoxication
Testing and Modifying Reaction Time
Subject sits on a chair and hold her fingers open around the base of a meter stick.
The tester will hold the top of the stick.
With no warning, the tester will release the meter stick.
When the subject notes its motion, s/he should grab it between the thumb and finger of one hand.
Note the distance (IN METERS!) at which the thumb touches the stick.

17. A) Testing and Modifying Reaction Time
Drunk Goggles are required for this part of the experiment!
Repeat this test 9 more times and place your data on the following chart.
Trial 1 2 3 4 5 6 7 8 9 10
Distance in meters

18. A) Testing and Modifying Reaction Time
Now convert your data into reaction time (seconds) using the conversion in your lab packet. Record your reaction time (in seconds).

19. A) Testing and Modifying Reaction Time
Q8: Why did we ask you to average trials 6-9 and ignore trials 1-5?
A8:
Q9a: How will distraction change the position on the meter stick that you catch at?
A9a:
Q9b:Will the distance on the meter stick increase or decrease?
A9b:
Q9c:Will the reaction TIME (units in seconds) increase or decrease?

20. A) Testing and Modifying Reaction Time
Now test reaction time being distracted… make it good… a real distraction…not just talking
Count backwards from 100
Speak in a foreign language
Alphabet in ASL
Are they ticklish?
Etc.
Record your distance for 5 trials and compute your reaction time using these 5 trials.
Calculate your distracted reaction time=_______s
Trial 1 2 3 4 5 m

21. B) Testing and Modifying Stroop Time
During each round of testing, the subject will have one job: to name the COLOR of the words that the tester points to… rather than reading the word.
The tester has two jobs in addition to pointing to objects.
Must record the time it takes the subject to complete the card
Must record the number of errors your subject makes. Errors?

22. B) Testing and Modifying Stroop Time
Repeat each level as indicated by the data tables shown.
Level
Time to complete
Errors 3
Average
Level
Time to complete
Errors 2
Average

23. B) Testing and Modifying Stroop Time
Level 2 is called “Congruent”
Level 3 is called “Incongruent”
Observe how much longer your solving time is when performing an incongruent test as compared to a congruent test.
Compute your INCONGRUENT average – your congruent average = ________________

24. Model IV
An “Expert Witness”, Dr. Greg Kane has a strong interest in the claims regarding the accuracy of field sobriety tests.
On his web site, he presents previously-obtained data showing the correlation (or not) of the one-leg stand test vs. blood alcohol content (BAC).
Q10: Is the OLS a GOOD test for intoxication? Why? Think like a defense attorney.
A10: