To wake or not to wake

To Wake or Not to Wake: Unveiling the mysteries of sleep consciousness

I was the last passenger to board a very full red-eye flight from San Diego to New York City. I scurried to my window seat, which required climbing over my already asleep neighbor. She miraculously stayed sleeping as I settled in next to her. And then, as I am inclined to do, I started wondering about her mind…

I could see her eyes move like that characteristic of REM sleep (Rapid Eye Movement). I knew that meant she was likely having a dream, but as to the content and nature of that dream? No idea. The only way I could know would be to shake her awake and ask her to immediately recall to me what was going on in her dreamworld. But, my social graces told me not to.

Fortunately for curious people like me, there are curious sleep scientists who do just that—wake people up and ask them about the moment ago when they were sleeping. One such group of scientists is working at the University of Wisconsin-Madison to develop new and improved methods for studying sleep consciousness. The team, led by Francesca Siclari and Joshua LaRocque, just released a report detailing their new method, and it’s potential for advancing sleep science.

Before explaining their new method, the authors acknowledge what’s typically been done. In a classic laboratory study, you (the subject) fall asleep for some researchers who have wired you to an EEG (electroencephalogram), which captures live readings of brain activity. An EEG can tell a trained eye which stage of sleep you are in, and so the researchers wake you up depending on what stage of sleep you are in, and how long you’ve been in that stage. At most, they might wake you up five times during the course of the night and ask you to describe the sleep experience you just left.

The Wisconsin team is doing things differently. Rather than wake you up at a few routine times throughout the night, they wake up you up randomly and often. Their hope is that this will make the data more representative of the enormous variety of conscious states during sleep. It’s not that they don’t care about what stage of sleep you are in—they care quite a bit—but they don’t want stage of sleep to be a deciding factor as to when they wake you up. So, they wake you up randomly and often, and ask a wide array of questions regarding the conscious experience you were or weren’t just having while asleep. These questions get at the content and nature of the dream: how long can you remember back into the dream; were you thinking or perceiving; was the dream mostly about you or was it more about your environment? So far, Siclari and LaRocque’s data is “in good agreement with the literature.” Meaning, a lot of previous data from sleep experimentation fits with what their new experimental method is showing.

But why are they trying so hard to understand sleep consciousness? Don't most interesting things happen while we are awake? And isn't it easier to study consciousness with an awake subject?…Sure, but great insights can emerge from studying what that something is not. So, if we’re interested in understanding the nature of conscious experience in wakefulness, we should also try to understand what happens to the conscious process in sleep. Furthermore, as we all know from having wild and crazy dreams, sleep consciousness is not devoid of interesting activity. This is partly driving Siclari and LaRocque’s work; sleep consciousness “undergoes major quantitative and qualitative changes in the course of the night.”  The asleep mind is far more complex than simply falling asleep in the evening and waking up in the morning. And the Wisconsin crew has moved us a bit closer to thoroughly investigating the complexity that ensues when we settle down to get some shut-eye.

Francesca Siclari, Joshua J. LaRocque, Bradley R. Postle and Giulio Tononi. (2013) Assessing sleep consciousness within subjects using a serial awakening paradigm. Frontiers in Psychology 4, 1-9.