To study your memory and sleep, use options available in SuperMemo in the following places:
You can use Tools : Workload (Ctrl+W) to inspect the daily and the monthly calendar of repetitions. You can view the number of repetitions scheduled, number of scheduled topics, number of scheduled items, as well as the record of past repetitions, and past retention, or how many new items were memorized.
You can inspect the history of repetitions for individual elements:
Inspect the timeline of repetitions and sleep:
Look for the best time for learning or sleep (see Timeline for details):
See how your brain gradually loses its power during the day:
Look for the time of the day that should give you maximum learning power (Shift+click a day in the sleep timeline). See when your learning is not likely to be effective and when you should rather go to sleep: