Freeman performing a trans-orbital lobotomy in 1949 |
I had a dream last night where an old friend from high school asked me, “what brain areas are involved in creating the thoughts we have during dreams?” I got a little excited and began to tell him that all of the posterior areas contribute but that the anterior, frontal areas are pretty much turned off. Actually, the prefrontal cortex (PFC) is the main area that is conspicuously missing during dreaming. It allows planning, self-organization and forethought, things that most dreaming is devoid of. Responding to the friend in my dream I rattled off a few names of areas that are turned on during dreaming: “the occipital visual cortex, the temporal auditory cortex, the limbic system, the somatesthetic…” But midsentence I realized that “somatesthetic” wasn’t a real word. It was a blurted-out mixture of somatosensory and somesthetic – a mistake I would never make during waking life. That I mispronounced this name so unhesitatingly clued me in to the fact that I was in the middle of a dream, not my high school cafeteria.
I was operating off-the-cuff, without inhibition or care for correctness. I made this mistake because my PFC was down. A funny thing about lucid dreaming is that thinking too hard after one realizes they are in a dream often catapults the PFC into full metabolic swing and the person into full consciousness. This is exactly what happened to me. Attempting to muster the cognitive wherewithal to correct my misstatement pulled me out of my dream and suddenly I found myself lying in bed in the dark muttering the word “somatosensory.” After tossing for a few minutes, thinking about the role of the PFC in sleep and wakefulness, I realized that, while dreaming, people operate as if they didn’t have a prefrontal cortex. It seems that the experience of dreaming replicates many of the elements of what it would feel like to be lobotomized. Patients that undergo a lobotomy have their PFC severed from the rest of their brain which causes them to act impulsive, eccentric and whimsical, to have a short attention span and poor reasoning ability. Honestly, this is how I behave while dreaming.
Lying in bed I came to the conclusion that lobotomized people probably feel and act as if they are in a dream state all of the time. Further, because other mammals have disproportionately small PFCs relative to humans (nonmammals don’t even have them), the experience of being another mammal may feel a little like dreaming. Further still, the way I act in my dreams would probably be very similar to how I would act if I were actually lobotomized. If a mid-century doctor plunged an ice pick slightly above and a few inches past each of my eye balls, and wiggled the thing around a little severing the connections between my PFC and the rest of my brain, I might just walk around rattling off over-simplified explanations in ways that that dream-people wouldn’t blink at but real people would institutionalize me for.
Interesting hypothesis. It makes sense. About six months ago, I dreamed that I won a huge lottery, 128 million. For a while, I experienced the thrill and excitement of winning such an enormous amount of money but at some point, became suspicious and woke up in the dream. I said to the person who was with me in the dream, "I know this is only a dream. I'd prefer not to be disappointed when I get out of bed tomorrow morning, so I'm going to wake up now." I was aware of waking up, of being in my bed. I knew I was awake but the dream wasn't over. I attempted to "turn off" the dream two more times until finally, thoroughly annoyed, I physically got out of bed to force the issue.
ReplyDeleteThis experience was strange since the two areas were clearly at odds and struggling for dominance. Makes me wonder how much of a part the dreaming areas of the brain play in waking imagination and creativity. While we know severing the PFC from the rest of the brain impairs cognitive functioning, what mechanism prohibits the dream state from overtaking the functions of the prefrontal cortex during the waking state?
Very cool story about the dream, I can see the "struggle for dominance." I like the way you posed your final question too. I don't know if there are any specific "dream areas" but many things change in the brain during sleep including neurotransmitter levels, melatonin level and frequency of rythmic oscillation. To answer your question we should find out more about narcolepsy, a very nebulous disorder marked by sporadic episodes of falling asleep.
ReplyDelete