Thursday, January 15, 2009

The Shutdown: Forgetting Dreams

I found it amazing that the majority of what I have been reading in my research book: “The New Science of Dreaming” that much of why our brain dreams is due to a combination of turning on or off different parts of our brain. Apparently our brains seem to be active during the day and nights in different forms. What I mean by this is that different areas of the brain are either on (partially) or off (partially) depending on what we are doing with it.

“PET studies show that there is also deactivation of the dorsoleral prefrontal cortex in REM sleep. The one brain area that remains as inactive in REM as it is in NREM sleep is the dorsolateral prefrontal cortex (DLPFC). “This DLPFC is thought to cause the forgetfulness during sleeping due to its “executive ego functions of working memory.” This shutting down of the PFC causes what is known as hypofrontality which is also experienced in altered states of waking consciousness.

During the shutting down of the DLPFC, the right hemisphere of the brain is activated as in NREM sleep cortical deactivation is greater. Evidence has shown through PET scans that “activity is even greater during REM than in waking in the inferior parietal lobe but only in the right hemisphere."

What we can learn from this is that during non-REM sleep and REM sleep, there is equal reason to not remember what we experience, along with different forms of altered consciousness. This could be explanation of why many of us don’t remember our dreams, mainly because our brain is shutting down how we naturally remember events. Apparently this is not an exact science since many people do end up remembering their dreams as well as some people actively controlling their dreams while being conscious during lucid dreaming. This would mean that it is quite possible that our brains have the ability to learn how to not shut down different areas of the brain during sleep.

As every event in our brains is controlled by electrical chemical reactions, we must always consider what types of neurotransmitters are causing the sequence of events such as PFC shutdown. There are a number of current theories on the subject, one stating that dreaming is a dopaminergic stimulation of the cortex during REM as a type of reward system. Taking a step back into the understanding of the action and reaction of serotonin and acetylcholine in the sleep process, it would make sense that during non-REM and REM sleep that serotonin has a larger role into the shutting down of the PFC, since it comes into play at a much earlier stage of sleep. It would be interesting to look into the affects of melatonin in the process as well.

I continue my research into the depths of finding the truths of why we dream.


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