Dr. Reneh Karamians

The Function and Neuroanatomy of Dreams

By Dr. Reneh Karamians, Psy.D.

Scientists and philosophers have been cogitating about dreams for a long time now. As an example, some ancient Egyptians believed that dreams were a doorway to a different dimension. Sigmund Freud, a 19th century neurologist and “wannabe” psychologist, wrote extensively on the topic and did so in a surprisingly cogent manner. Freud, ever the scientist, atheist and skeptic, took an evolutionary approach to the problem of dreams and stated that dreaming served a purpose for the survival of early humans. Freud postulated that 1) dreams happen to keep early humans asleep when minor phenomena within the environment present themselves (e.g., hunger or needing to pee), 2) dreams served early humans as an internal alarm to help them wake up when major environmental dangers presented themselves (e.g., There is a lion in the cave!).

Dreaming to Stay Asleep

In the case of the former, what Freud called the “manifest content” of the dream would occur in such a way as to keep the individual cave person (cave person, is that P.C?), the evolutionarily challenged individual, asleep. As an example, a hungry person may dream that he or she is eating to fool the mind into thinking that the body is receiving nutrients to prevent awakening. This, more than likely, occurred because sleep, in the case of early man, was probably more important than eating right away. Some Freudians also call this a “wish fulfillment” dream (though it would be a boring one and one unfit for further analysis). Still, these types of dreams can become very complex and convoluted especially in individuals suffering from certain types of disorders and syndromes as described by Dr. Freud.

Dreaming to Wake up

Ever dream that someone is in your room and so you jump awake, terrified? Of course you have. We all have! These are the kind of dreams designed specifically to wake us up because the mind perceives a danger in the environment (even though sometimes there isn’t any danger). Pretty simple no? Surprising given these are Freud’s descriptions! Well, to be completely honest, Dr. Freud has a lot more to say about dreams than what I have presented here. The majority of his work on dreams is presented in an essay appropriately titled “On Dreams”. The aspects of his theories on dreams which I have presented here were taken from his essay “Totem and Taboo”. So have a look at those works if you have the time!

Neuroanatomy and Dreams

Okay, so in the title of this brief article I promised to tell you how the brain causes dreams and what parts are involved. The truth is, this topic is a bit boring. This is because the brain regions involved in dreaming are precisely the regions one would expect to be involved in dreaming! But I will tell you all about it anyway. Who knows? Maybe you’ll find this interesting.

The way we brain freaks study how the brain dreams is by watching brain blood allocation during dream states. The results of these types of studies have largely left scientists baffled but we have learned a few things. For example, we know that while participants are dreaming, a region called the Pontine Tegmentum which is located within the base of the brain as a part of the Pons region (so think back of your head where your head meets your neck) tends to “light up” in imaging studies (see figure 1).

FIGURE 1: The Pons

This region is typically associated with motor function as well as arousal. This is an important aspect of the dreaming process since this region is, more than likely, the region which causes the temporary paralysis which occurs during dream states (ever feel like you are awake but you can’t move right away, that’s right, now you got it!). If the temporary paralysis did not occur during dream states, the organism, in this case you, may hurt itself. Imagine if you are dreaming you are running and your legs start kicking (kind of like a dog)! Your partner wouldn’t like that very much.

Another region which “lights up” during these studies are the bilaterally located Amygdaloid regions. These two almond shaped structures are located deep beneath the cortex (or surface of the brain) and sit atop the Hippocamal regions which are involved in long-term memory (see figure 2). However, the most important function of the Amygdaloid regions is to produce emotional responses and especially fear and anxiety based emotions. So, again, since many dreams contain some sort of emotional content, it is not surprising that this region would be involved in dream states. One might postulate that this region is most active during anxiety dreams (e.g., you’re getting chased) and nightmares.

FIGURE 2: Amygdaloid Regions

Other regions involved are the left laterally located Thalamus, which is often described as a “hub” since this region has many connection throughout the brain, and the Anterior Cingulate Operculum, which is primarily involved in attention, motivation, regulation of emotional content and facilitation of how one relates to others. This latter region is one of the regions which is activated when a mother hears a baby crying and is located behind the Frontal Cortex (see figure 3).

FIGURE 3: Anterior Cingulate Cortex

Again, it is not surprising that this region is active during dreams since it involves perception of relationships, and pleasant emotions such as lust. So the next time you have a naughty dream about someone you were not supposed to, you can tell your partner it was your Anterior Cingulate Operculum!

Finally, and perhaps the most interesting of all, there are certain brain regions that “turn off” (not literally of course, more like “slow down”) while one is dreaming. One such region is the Prefrontal Cortex which is, well, it’s that voice in your mind that tells you that you shouldn’t have that last piece of pizza, or that slice of pie after a big dinner. This region helps you to make “smart” decisions and helps you to solve complex problems. Now, the question is, why would your brains “supervisor” be “turned off” while you dream? It is difficult to find an answer to this question within the literature (and yes, all this is based on peer reviewed and published work; Maquet, Peters, Aerts, Delfiore, Degueldre, Luxan & Franck, 1996). However, one might postulate that one of the purposes of the dream state is to allow the mind to wander without the restrictions provided by the Prefrontal Cortex. Perhaps this is one aspect of the rejuvenative nature of the dream state. This also explains why our dreams are often bizarre! Of course Dr. Freud had other thoughts on this but, then again, he used Cocaine as a decongestant. Literally!

By Dr. Reneh Karamians, Psy.D.