Name: Key, Key
Date: 5/31/2004
Article: McCarley et al. (2004).

1. What was the purpose of this research?
a) Study effects of practice on x-ray screening
b) Determine if effects of practice (on scanning and/or recognition) are stimulus specific

2. What did the researchers do? (Summarize method,including groups, manipulation(s),
and dependent variable(s))
Had people practice recognizing targets (knives)within pictures of x-rayed luggage. Subjects had
4 practice sessions with one set of stimuli and then they attempted to recognize new stimuli. Recorded
eye-movements, reaction time, and accuracy.

3. What were the main results? Sensitivity and reaction time improved with practice. People found
targets with fewer eye-movements with practice. People’s ability to recognize targets only improved
on trials in which subjects fixated on the target. Sensitivity decreased between trial 4 and 5 but it (as
well as RT) improved between sessions 1 and 5.

4. What is the take-home message (conclusion)? Practice leads to improvements in recognition
but not scanning. Practice is somewhat stimulus specific because switching targets lead to decreases in
performance.

5. Are there any problems with the research or do you have any criticisms? Is there anything
you would do differently? Limited set of stimuli and luggage samples. Controlled placement of objects
in bags. Controlled practice in ideal situations. Ss were told they were looking for knives.

6. Special question: Will be assigned separately for each article/reading.
What do these results say about how to improve safety screening at the airport?