In this series, I dig a little deeper into the meaning of psychology-related terms. This week’s term is dreaming.
We all have dreams, whether we remember them or not, but what exactly are they? The reality is that no one really knows for sure. There are a few things we do know, though.
Dreams occur mostly during the REM (rapid eye movement) phase of sleep, when the brain is quite active. The duration can vary from seconds to half an hour, and on average people have 3-5 dreams per night with dream phases 60-90 minutes apart.
Some dreams occur during deep sleep, but these are less vivid and not usually remembered. These are mostly associated with the hippocampus consolidating information into long-term memory.
REM sleep is a rather fascinating phase. On an electroencephalogram (EEG), the brain looks almost as active as when it’s awake. However, the brain does not release the neurotransmitters norepinephrine, serotonin, and histamine during this phase. The prefrontal cortex, which handles higher level cognitive functioning, is less active while dreaming, which may be why dreams can feel very real even if they’re bizarre.
It’s unknown what part of the brain generates the vivid imagery of REM dreams. It is clear, though, that it is not the same part of the brain that’s used for imagination while awake. Increased dopamine release is associated with increased vivid dreaming and nightmares, while suppression of dopamine transmission, such as with antipsychotic medications, is associated with decreased dreaming and less vividness. Antidepressants that affect serotonin can sometimes cause increased vividness of dreams.
All mammals are thought to go through REM sleep, and signs of dreaming have been observed in a number of animals. I’m fairly sure that I’ve watched my guinea pigs while they were dreaming.
The meaning of dreams from a neurophysiological perspective is unclear. Some researchers think that they’re involved in consolidating the day’s events into long-term memory. Others suggest that it’s the brain randomly putting together bits of information from stimulation of the posterior part of the brain.
Sigmund Freud believed that dreams were manifestations of one’s deepest thoughts and feelings, including repressed memories. Unsurprisingly, perhaps, he also thought that dreams were also a release of sexual tension. He believed that while in a dream state, the super-ego relaxed, and the id could really come out to play. Dream interpretation was an essential part of psychoanalysis, and continues to play an important role in that field.
Dreams have been interpreted as having divine significance since early Egyptian times. Now, there are plenty of sites scattered around the internet that will tell you what each specific element of a dream means. There doesn’t appear to be any research to back up these various symbolic interpretations.
Psychologist World has a rather lengthy list, so for fun let’s consider a few:
- Bigamy: for a man, “loss of manhood and failing mentality”, and for a woman, “she will suffer dishonor unless very discreet”
- Bonnet: “much gossiping and slandering”
- Buffalo: “if a woman dreams of killing a lot of buffaloes, she will undertake a stupendous enterprise”
- Camel: you will “entertain great patience and fortitude”
Personally, I think the symbol business is a load of BS. Sure, elements of dreams may mean something, but to me “bonnet” means Laura Ingalls Wilder, and to someone in the UK it means part of a car, so how could it mean the same thing in a dream? In more general terms, though, we all have a unique set of past experiences and memories, and as a result, we may each have very different associations with a particular item. If dreams do have a deeper meaning, I suspect it would be far more individualized than bonnet = gossip.
I seldom remember my dreams, which may be that I seldom get woken up out of REM sleep. My personal take on it is that dreams don’t necessarily have much meaning. We are bombarded with so much sensory information during the day, much of which our brains conveniently filter out of our awareness. There’s also our long-term memory banks, which aren’t that well understood. It makes a lot of sense to me that dreaming is what comes flying out while the brain is filing away all that information.
But who really knows, right? It could all just be a conspiracy of Laura Ingalls Wilder and her gossipy bonneted friends.
You can find the rest of my What Is series here.
- How Stuff Works – Science: What are dreams?
- Psychologist World: Dreams dictionary: Meanings of dreams
- Wikipedia: Dreams
- Wikipedia: Psychoanalytic dream interpretation
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