From another hole far from the first, another mammal of the same type emerges to look for food. Something is different about this mammal. This mammal can mix together what it is perceiving with what it is remembering to create an experience-of-sorts that it has never actually experienced.
This mammal also locates some fruit to bring back home. A large piece of fruit and a smaller piece stand before her. The large piece is tempting because of its size, but the perception of the fruit overlaid with a flash of a memory of her home hole unleashes a tinge of fear in her as she momentarily “views” the large fruit blocking her home hole. She performs the same internal mixing with the smaller fruit and feels good about the result. She nudges the smaller fruit back home and safely down into the hole where all there can feast.
The power to mix perception with memory to create something fictional ultimately has survival value. We might think that it would always be more desirable for our neural states to accurately represent what is being perceived. However, producing useful fiction gives our second mammal a distinct advantage over those that are confined to facts.
By mixing, we mean that the neural activity triggered by what is perceived is combined with the neural activity initiated from a retrieved memory. The result is a state of neural activity that represents a fiction—something never actually experienced. By memory, we mean a reinstatement of neural activity that strongly resembles the pattern of neural activity during the initial experience. The same basic system is at play for perceiving, remembering, mixing and ultimately planning.
The mammalian brain already engages in mixing of several kinds. We are just hypothesizing the onset of one more type of mixing, that between perception and memory. Three examples of other mixing: First, the input from our two eyes is mixed (i.e., combined) into a unified visual experience. Second, as our eyes dart back and forth (i.e., saccade) across a scene, each time the eye stops it takes in a small clearly focused area of the scene that is surrounded by a blurry periphery. The illusion we experience, however, is that the entire scene in front of us is basically in focus. The brain mixes together these little clear snapshots over time to give us this illusory experience. Third, our brain combines our multiple senses into a coherent experience. When we watch someone talk, it is not like a bad movie where the mouth movements are out of sync with the words. We take it for granted that our brain performs this timely combination. In sum, the brain is very good at mixing. Possibly, at some point, it also became good at mixing perception with memory to produce useful fiction.
The sensorimotor system of the brain is comprised of all the areas that process the various senses plus the areas that devise and execute a plan of action. To explain how our mammal solved the fruit problem, we did not need to posit that its brain possessed a specialized area for analysis. All we had to do was tweak the input to the sensorimotor system and let it do what it is designed for: make action plans in response to its input. As we will see when we examine the neuroscience evidence, the sensorimotor system is very good at planning the next actions based on what is being perceived. This system serves the mammal well for dealing with the immediate future. By altering its input and making plans based on something partially fictitious, the mammal can now use the same basic system to deal with the non-immediate future.
This small change in neural functioning produces a huge advance in cognitive ability, which gives it a good deal of evolutionary plausibility. A mammal that was once constrained to the present and immediate future is now freed up to consider the non-immediate future of possible events, hypothetical situations, and counterfactual scenarios.
Does our ancient mammal experience an aha moment? The fearful response to the image of the fruit blocking the hole certainly came on suddenly, which is consistent with an aha moment. The neuroscience of human aha moments, however, suggests other characteristics that may only be possible for a language-using animal. Our ancient mammal most likely experienced an aha moment, but one that is slightly different from a human experience.
In this article, we first look to autism for hints on thinking in images. Second, we look at the neural evidence of how memory (a perceptual reconstruction) and future thinking (a perceptual construction of a possible future event) are almost neurally indistinguishable. The neural evidence will help us conclude that early problem solving in mammals is a special form of future thinking. Third, we show how the onset of words came from our brain’s association-making abilities and how words add control to our mixing capacity.
In the next installment, we set out the possible neural mechanisms that permit mixing to take place.
Contact Tony McCaffrey (tony.mccaffreyphd@gmail) with questions or comments.