Sunday, March 27, 2011

Thoughts on Dreams

Long post - just keep reading. Sorry there are no pictures - My lovely, pink Sony Cybershot does not accompany me in my dreams. Besides, dreams are more of a film than a snapshot.

I woke up this morning (well, it's nearly the afternoon actually), and as usual realized I'd had some bizarre dreams. For me, my dreams are incredibly vivid - I remember very specific details about them, and they don't fade after I wake up. My dreams nearly always relate to my life in a way that's pretty simple to decode.

While still in bed, I was thinking about the construction of dreams. What tools do we use to compose a dream?

In general, our sensory systems are shut down when we sleep.
Vision - Our eyes are closed. You can't see with any decent resolution through your eyelids.
Hearing - We block out or ignore most quiet noises.
Taste - Well, I definitely can't remember the last time I ate a burrito while sleeping. I doubt you can either.
Smell - A smell probably won't be the stimulus that wakes you, though you may notice a pleasant breakfast odor when you wake up...unless you live in my apartment.
Touch - Definitely off. Do you feel your sheets, blankets, pajamas, or hand on your teddy bear when you roll over or move? No.

Additionally, our major muscle groups are temporarily paralyzed to prevent us from "acting out" the dream - which is good - doing pirouettes with my eyes closed would just be a disaster.

So, with all these sensory systems asleep, you might point out that in fact we do seem to see in our dreams. There can be dialog which we hear, aromas to smell, and even a touch.

In Meditations on First Philosophy, Descartes claims that our senses deceive us in dreams. We're not seeing through our eyes, yet we manage to "see" things and process images. So where do they come from?

My thought on this matter is that we rely almost completely on cognitive processes to fabricate a dream. These cognitive processes usually relate to or are based on experiences from conscious life. I guess Descartes might have said that too, but my book is at home, and I can't quite remember. Anyways, here's what I was thinking about:

Vision - All we see in a dream - a location, a person, a costume - is a replica of something we've seen while awake. The images may be synthesized in a nonsensical being at your elementary school, wearing pointe shoes, and talking to a friend from college...but they're all based on a memory of previously seen images.

Hearing - I have a lot to say in my dreams, don't you? Interestingly, another person's vocal qualities are typically the same in your dreams as they sound in conscious life - again, based on what you've previously heard and are remembering.
The sense of hearing, brings up another odd aspect of dreams - language. Language is the lens through which we perceive the world. We name everything and describe it's qualities and function in order to make sense of it. Interestingly, language carries over into dreams, at least it does in my dreams. Apparently, once we learn to speak/read/write, we cannot dissociate language from our perception of the world. We apply language to a situation immediately, and there's no going back. Guess what? It seems that language is applied in dreams just as quickly. I wonder if I'll be dreaming in Spanish next year when I live in Madrid. I also wonder what my dog's dreams are like...she's not so big on language.

Taste -Well, I suppose you might eat in a dream. In this case, you're probably eating something you've actually eaten in your conscious life, so you'll perceive the flavor of that food - it's a cognitive process, obviously since if there's nothing in your mouth you can only "fake taste" it at best. If you're dreaming of a food you've never eaten, but just seen or heard of, you'll probably "guess" the flavor incorrectly. I know this can connect with smell too, but I'm not going to digress.

Smell - I can definitely remember smelling some things in my dreams. However, again, I believe this compromised sense of smell is merely the memory of something I had smelled while awake. I can tell that it's nothing more than an unconscious memory since the odor fit well in the nonsensical construction of the dream, but had no place in my apartment. Trust me - neither the tantalizing aroma of a Thanksgiving turkey, nor the foul odor of cigarette smoke will ever come from my apartment. Just popcorn. Lots of popcorn.

Touch - So, I had this weird dream where I was running on nails without shoes. Strangely, it didn't hurt my feet, because I just kept running. However, I remember expecting it to hurt and not wanting to keep running, since I knew (from being awake) that that type of experience would likely be excruciating. So, remembering what is and isn't painful seems to be intact, yet the actual sensation is totally gone.
Have you ever felt the wind in your hair in a dream? Or the warm sun on your face? Well, living in an apartment where the windows don't open, there's definitely no real wind. In my former apartment, where I always slept with the window open, I never noticed wind in a dream - inverse situation, same conclusion. Clearly, feeling wind or sun shining, is just a memory from being awake.
Sometimes the associations with setting and feelings are wrong though. Yesterday I dreamed I was swimming in a dark, freezing late in Iowa and Minnesota (yes, the location makes no sense). Oddly, I wasn't cold in the lake in the dream. Weird, right? - That would be so miserably cold.

Another component of dreams is emotion. As far as I can remember, emotions that can be felt in dreams include emotions associated with the above senses, as well as fear, anxiety, excitement, contentment, hesitation, impatience, anticipation, resentment. I'm sure there are more. I guess each of these emotions is really how we know we should feel in a given situation. If chased, we'll feel fear, but never lose our breath. If auditioning for a performance, we'll feel excitement with a touch of anxiety. In any case, the bottom line seems to be that dreams are just cognitive constructions in our minds, built from our experiences and memories. We are great designers - there's a setting, a plot, characters, and an emotional response.

Side note: Many of you know that I work in a lab at BU that does Alzheimer's research. I'm sort of curious how an Alzheimer's patient dreams, if dreams are based on memory. Would a dream be frustrating? Would there be blank spots, or would the person just fill in something else?

Here's an exception: If all these sensory systems are temporarily off, why does our alarm clock wake us? Why does someone poking you wake you? Why does opening a window to a flash of sunlight wake us? Do these things always wake us?

A noxious smell, or painful touch provokes a sort of alarm-like response as a protective mechanism. It alerts us that something is wrong, and lets us act. With a painful pinprick, we remove our finger instantly - before we think and realize what happened. Perhaps an alarm clock scares us a bit, therefore waking us. Wow, that seems mean.

Another question - obviously, these sensory systems can be jolted to alertness in order to wake you up. So, what conditions are required to let you stay asleep? When you wake up late on a weekend without an alarm clock, how does that transition from asleep to awake happen? This seems to be an intersection of neuroscience, philosophy, and psychology. That's pretty sweet. Neuroscience!!!

3rd side note: For those of you who read one of my past posts in which I think I wrote that I have a habit, that I never intend to break, of minimizing emotional responses when I'm awake, and are now concerned that like all the emotions I listed for dreams are tense or, don't worry. And please don't psychoanalyze me. And if you do, please don't tell me. I'm obviously happy - I'm living in Madrid next year and have been accepted to grad school for neuro!! Life is good, and everything is coming together perfectly. It couldn't be going better.

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