Imagine sleep without dreaming

What about dreams?

We've always asked about the importance of sleep, but what if sleep is only half the equation? What if the other half is to dream? I've always been skeptical about dreams having any real importance. I've considered it more of a residual brain activity during which the brain is detoxifying and the body saving energy during half~ of solar cycle (24 hours). But what if dreams are actually important? The interesting thing is that many animals dream, from puppies to songbirds. It wouldn't surprise me if many nervous systems sleep AND to dream. This was brought to my attention by an odd conjunction between psychologists, computational scientists, evolutionary biologists and social philosophers all saying the same thing. It is a big advantage to simulate activity especially when the activity is either energetically costly or important.

Balancing growth with dexterity:

Dreams may be especially important in younger individuals. As a young animal (including humans) it is important to grow and quickly gain the dexterity and skills to be able to ensure metabolic and then reproductive success. This is effectively a race, balancing a multitude of skills/abilities with physical growth. These two are actually at odds. Gaining skills requires environmental interaction, even learning to walk is energetically expensive, which could be used on growing in size instead. Playing is a way of understanding how the body moves in relation to other things in the environment and is important where dexterity and coordination is critical to food acquisition and avoiding predation. Sleeping and dreaming is a way to achieve both goals. Sleep is metabolically less demanding allowing for the prioritization of physical growth. Dreaming would allow for neural pathways to simulate environmental interaction based on what was done while awake. Thus dreaming is a less-constrained activity where energy is expended on neural activity and not on whole body muscle activity.

What does this model predict?

If this model is accurate, the most common form of dreaming should be the use of neural circuits that were active while awake. Whether this be for songs sung during the day or littermates that were played with, dreaming would be an exercise in dexterity and coordination without the expensive use of muscle activity. This follows evolutionary theory well in that energetically costly behavior should be reduced as an individual develops. Dexterity and coordination are means to reduce wasteful or harmful movements. Thus continued simulation, will allow neural circuits to select for pathways that minimize wasteful energy expenditure. To stay properly rooted in environmentally accurate simulations, it is important that frequent cycles of sleeping/dreaming is followed up by feedback between the waking environment. Failure to develop dexterity and coordination that matches the physical environment will simply result in increased energy expenditure, if this energy expenditure exceeds what can be acquired from the environment the individual will fail at living. In such a way, if dreaming improves dexterity, dreaming can easily be retained and improved through natural selection.

Why are human dreams so weird?

Human dreams may be an exception to dreaming experienced by many other species. This is because our environment includes social and mental constructs that do not have a physical presence in the world. Thus the more exchange of mental constructs (aka ideas, religions, ideologies, and phantoms) the more that our dreaming selves will try to simulate non-physical combinations of mental constructs with our physical environments. To test this model one simply needs to compare the typical dreams of socially isolated peoples imbedded in natural environments compared to highly social peoples that interact with a wide number of environments of varying human input. Dreaming that doesn't match the observed physical environment, (aka weird and wild dreams) can continue as long as the dreamers can get enough food and resources to successfully reproduce. This is concept is even more important because humans may be one of the few organisms that can dream while awake.

The human imagination

The human imagination can be conceptualized as active/guided dreaming. We are simulating activity and scenarios while more actively adding environmental constraints to the simulations. Human imagination may even be a response to the failure of dreams to distinguish and restrict mental construct simulation in physical environments. MAYBE our dreams became too free. However, our mental constructs are important, particularly as social organizations become larger and more complex. Imagine maintaining social order without the mental constructs of "justice" or "equality". These are hard won ideas that have improved our social success. A valid solution is to take something we already do, dreaming, and add more active constraints to account for increasingly complex social and environmental interactions. Interestingly we could view this from the opposite perspective. What if early humans developed a way to more actively guide the process of dreaming? This could have allowed for us to make mental constructs and eventually these mental constructs were used as the solutions to our increasingly complex social networks and constructed environments. Thus imagination could actually reinforce the inadequacies of dreaming, making humans increasingly imaginative!

-Read more on human imagination in other posts