This week we focused on sleep. We learned a bit about each other's sleep habits (how many hours of sleep we typically get; how difficult it is to fall sleep; whether it's difficult to wake up in the mornings; whether we wake up in the middle of the night; whether we can remember our dreams). We learned how much sleep humans typically get over the life span, and how much sleep different animals get (squirrels sleep a surprising amount). We learned about different stages of sleep (REM and different stages of NREM) and how brain signals look like during the different stages. We compared EEG, EOG, and EMG signals during awake, REM, and NREM, and we watched this youtube video to really see how these signals change over the sleep cycle: (notice the changes in frequency and amplitude between signals at different stages). 

We learned about "deep sleep" and how bedwetting, sleepwalking, and night terrors typically happen at this stage of NREM sleep. We also learned that dreaming occurs during REM sleep, and people who wake up at this stage can typically remember their dreams. We also covered different ideas on the functions of sleep (e.g., for memory and learning, as an adaptive process) and psychological and physical effects of sleep deprivation.

We ended by talking about dreams. There's little scientific evidence that dreams hold special meanings or that they reveal insights. Indeed, a popular neurobiological theory (activation-synthesis hypothesis) suggests that dreams are simply the brain's way of interpreting and creating meaning from neural activity across different brain circuits during sleep. However, I think there is agreement that our day-to-day experiences can influence our sleep and perhaps the contents of our dreams. 

Here are some questions that would be useful to keep in mind when we think about our dreams (courtesy of Eric Chudler):

1. Are your dreams in color?
2. Do you have a "sense of time" in your dream?
3. What emotions did you have during your dream?
4. How many different dreams can you remember in one night?
5. Do the same people, events or places reoccur in different dreams?
6. Do some events that happened during the day appear in your dreams?
7. If you think about something before going to sleep, does this "something" appear in your dreams?
8. Does watching a movie or a TV show influence what you dream about?
9. Does eating certain food influence what you dream about?
10. Does your mood affect what you dream about? If you are happy, do you dream about different things than if you were sad?
11. Are dreams on weekdays different than dreams on the weekends?
12. Does the time of year influence what you dream about?
13. Does the time you go to sleep influence what you dream about?
14. Are nighttime dreams different from dreams you have if you take a nap (or fall asleep during class)?
15. Are dreams different when you are sick?
16. Are dreams different when you take medicine?
17. Do you remember dreams you have had in the past? How long ago?
18. Do you have the same dreams more than once?
19. Are your dreams similar to the dreams of other people in the class? Compare some of your notes.
20. Can you remember your dreams better when you wake up by yourself or when you wake up with an alarm clock? 

Exercises for the week: I provided the students with a sleep log and a dream log, which I hope will be filled out throughout the week!

Cheers,
Lily