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Surprising Science

What On Earth Is Going On When We Dream?

Sleep psychologist Shelby Harris reviews ideas about what dreams may be.

Dreams fascinate many of us. What are they, and what do they mean? Why do dreams for some people continue across multiple nights in places familiar to us only from dreams? Why do they make no sense at all and yet perfect sense while you’re asleep? What are sleepwalkers dreaming about?

To the tune of “Have You Ever seen a dream Walking”

There’s no shortage of theories. Freud and Jung famously saw value in poring over them for messages contained within their symbols, typically relating to wish-fulfillment or conflict resolution. Some modern researchers have concluded that due to the increased presence of the hormone cortisol during dreams, that they have no meaning at all, being nothing more than us eavesdropping on the brain as it shuffles memories around in order to sort some into long-term memory and discard others.

Sleep psychologist Shelby Harris proposes something in-between.

According to Shelby, yes, it’s memory-sorting, but it’s not simply a mechanical process: It’s you going through recent events to work through them, deciding what you care about, and forget the rest.

She also points out that there’s still a great deal of controversy among experts about what dreams are. Which is another way of saying we still don’t really know

Dreams might be a whole lot sexier than we thought – but not because of their narrative content. Neurologist Patrick McNamara’s theory links the biological changes in our brains during sleep to human’s inherent desire to procreate.
With brain scans, scientists have learned much about what happens in our heads during sleep, but they still can’t answer the simple question: why do we sleep?

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