Study Description: Sleep and Memory Recall

A researcher wanted to investigate whether a brief afternoon nap would affect memory recall in university students. Previous research had indicated that sleep consolidation improves memory performance.

The researcher used a repeated measures design with 25 undergraduate students. All students participated in both conditions:

• Condition A: Students had a 20-minute nap in a quiet room immediately after learning a list of 40 words.
• Condition B: Students sat quietly, remaining awake, for 20 minutes in the same room after learning a different list of 40 words.

After the 20-minute period in each condition, students were asked to recall as many words as possible from the list (scored out of 40).

The researcher found that the difference in recall scores was not significant at the 0.05 level.

The researcher was concerned that there might have been a Type II error.