“Life is just one damn thing after another!” – Anonymous [1]

With the U.S. presidential election basically over and the coronavirus crisis response stuck in political denial (despite a new surge), I am overdue for a science-geeky post on a neglected recurring topic here, that of human volition (i.e., “choice” or “free will”). [2]

The impetus for this post is the apparent confirmation of the existence of “time cells” in the human brain. These are a sort of “time stamp” that enables us to put our stored memories in “time order.” Time order is essential in the development of both human volition and consciousness. Indeed, we might look at consciousness itself as “watching time go by.”

The title of this post is my simplification of a widely held scientific view of human consciousness. Much (most?) of our brain is active 24/7 doing a ton of unconscious thinking, what I call the body “watching itself” on the first order. In other words, our brain is always unconsciously monitoring the autonomous bodily functions like breathing and digestion required to keep us in homeostasis, the equilibrium of chemical balance required to maintain an ongoing living organism. [3]

Early 20th century postcard.

But in addition, my human brain (and possibly other mammalian brains beyond the scope of this discussion) appears to also work at a second-order level where I am “watching myself watch myself.” That is, I can somehow “switch on” a brain mode in which I consciously “listen” to my own breathing and other bodily functions, or perhaps even alter them through what at least appears to be some kind of choice. I can, though this volition, hold my breath for a short time, or I can swallow an antacid tablet to alter my digestive chemistry. The aforementioned “time stamp” brain cells may well be a key to better understanding this “second order” brain function.

Time after time…

Scientists have long known about apparent time cells in rodents, but this study, which was recently published in the Proceedings of the National Academy of Sciences, reports on an experiment that demonstrates these cells in human brains. Using epilepsy patients being treated for other issues, the researchers were able to document critical biological processes resulting in episodic memories, which are “stored” events that you can “retrieve” in time-sequential order.

I have to stop and say here that all attempts to simplify this type of scientific research via non-biological models is fraught with the danger of inaccuracy. I am not a neuroscientist, and so I especially run this risk. Memory “storage” and “retrieval” are common models of this sort, pulled from computer science to simplify a complex process. But that expression may not necessarily be completely accurate when you get down to the level of brain chemistry. The brain is not a digital machine. However, even most neuroscientists commonly use these “computer model” terms of storage and retrieval because, like a favorite Van Morrison song says, they may be “close enough for jazz.”

I came to the study of volition first through the formal study of ethics, via earlier study in computer science, applied math and corporate finance. It became clear to me early on that the uses of the terms volition, choice and free will in the study of ethics are undergirded by a deeper “reality” of biological processes. These terms put into more accessible language the biochemical interactions happening at that first, unconscious, level of brain function where “A or B switch” actions appear to occur (another likely-inadequate model taken from electronics and computer science). We at least appear to be choosing to, say, turn right or left. That is volition, however it happens exactly

An example of one complication challenging our “higher order” representations discussed in this research study is to tackle specifically what time itself means. Regardless of how these events were encoded, the “time clicks” did not necessarily correspond to one steady “clock time.” This may be a partial explanation of why we recall traumatic events as if time has slowed down while other stored events seem to be compressed in time, especially as we grow older.

“There is no neural clock,” says Gyorgy Buzsaki, a neuroscientist at New York University. “What happens in the brain is neurons change in response to other neurons. Having said that, it’s a useful concept to talk about how this neural substrate represents the passage of what we call time.” In other words, like neurons involved in determining the “place” of a memory, the “time information” is likely encoded in the interlinking structure of neurons to other memory neurons.

Watching yourself fall asleep

We use the language of computers, as well as classic philosophy and theology language, to describe what is going on in our brains. These are the tools with which more of us communicate with each other as opposed to the language of biochemistry. I liken this simplification as like being able to drive a car without knowing exactly how the engine works. Most of the time our limited vocabulary about automobiles can get us where we need to go. We humans have, in effect, created these “second-order languages,” evolutionarily “choosing” how we will communicate with each other. And using these adequate-enough terms, we can describe, either internally or to other people, the process of “watching ourselves” execute these basic first-order bodily functions, one conceptual notch above the level of biochemistry.

Our daily sleep cycle is an obvious example of how we “give up” watching ourselves watch ourselves at least once every day. Those “time cells” may have a crucial role here as well. You likely do not remember the exact moment at which you fell asleep last night. The reason for this could well be as simple as that your brain’s “memory storage” stopped recording these “time stamps.” And without those time markers, your sense of consciousness is basically gone. Just about everything we “consciously” do involves some kind of “time order,” for instance just reading the words on this page.

It is a bit of chicken-and-egg here. If you have ever been put under anesthesia, did you recall losing all sense of time because you were unconscious, or were you “not conscious” because there were no “time stamps” being recorded in your memories? While we commonly have thought the former, this research suggests looking at consciousness the other way around. No time cells “saved” (by some form of neuron interaction) perhaps means no or little conscious awareness, because we cannot consciously recall of the sequence of “first this happened, and then that happened.”

What about dreams? I subscribe to the hypothesis that dreams are most generally a kind of “garbage collection” process (again a too-simple analogy from computer science for a complex phenomenon) where the brain is subconsciously trying to make associations between stored, time-stamped memory events in order to determine which memories need to be more permanently saved, versus which ones can be jettisoned to free up “space” in your brain. This is sometimes called reverse learning. The resulting random attempts at establishing connections between unrelated memories possibly explain our weirdest dreams. [4]

The perception of time itself also appears to be distorted in dreams. What we think may be a long dream has been demonstrated to have at times lasted only seconds. Again, the “time stamps” are being dredged up, but likely not necessarily at the same “click rate” at which our conscious brain normally functions.

Planning ahead

In his very readable books about biological evolution from fish onward to humans, paleontologist Neil Shubin notes that fish cannot see very far ahead in the water, and thus their brains likely cannot plan very far ahead in time either. [5] When their evolutionary descendants started venturing out of the sea about 375 million years ago, vision got better and brains also got bigger, gaining the ability to both see farther ahead in distance and plan farther ahead in time. That plan part is where these time cells likely come in. Humans not only have the ability to recall complex sequences of events by “time stamp” as they had occurred in the past, but we can also “visualize” many possible time sequences of events well into the future.

In philosopher/neuroscientist Daniel Dennett’s description, the vertebrate brain evolved as an “expectation generator.” Over millions of years we have gained the ability to understand, and then probabilistically predict, the if-then outcomes of possible actions, sequenced by time that has not yet happened. We can then act accordingly to improve our chances at survival. In effect, we can imagine multiple “possible futures of sequential events,” which in turn “tweak the odds” of our future survival. [6]

By sequencing both past and future events in time, our brains can “go meta” to create an “artificial reality” (our imagination) that prepares us for the future, or even just entertains us through the creation of fantasy worlds that will never “happen.” All by watching ourselves watch ourselves.

Using this creativity of metacognition, Lewis Carroll and Walt Disney demonstrated how White Rabbits can be “late for an important date.”

Notes:

1. This quote is often attributed to Mark Twain or H. L. Mencken but its actual origins are more fuzzy.
2. As I have frequently noted in the past, the terms choice and free will both have a lot of political and theological “baggage.” Because of that, I prefer to use the term volition, which I define as “whatever biological process causes you to reach for the chocolate cake instead of the fruit in front of you.” I do not see volition as in any way mystical, rather, whatever philosophy or theology we place on that volition is human-created language at another order of aggregation.
3. Neuroscientist Antonio Damasio, in his book Self Comes to Mind and in other works, expresses the idea that homeostasis is fundamental to the definition of what makes something “alive.” He also describes consciousness as what happens when “the brain gets a self.”
4. The computer science analogy of garbage collection obviously has its word source in the actual collection of trash from the street, but it has been a fundamental building block of the discipline from its beginning. When I first started programming computer graphics systems in just 64,000 bytes of computer memory in the early 1970s, every bit was precious, and programmers had to find an efficient way to regularly gather and reorganize all computer memory that was no longer being used. While this still happens in your personal computer’s operating system, memory has become so cheap that you may never have to recycle memory on a multi-terabyte backup disk drive.
5. Neil Shubin’s “must read” books are Your Inner Fish (which has been turned into a fascinating television series now available on YouTube) and Some Assembly Required.
6. Daniel Dennett’s most extensive discussion of volition is in his book, Freedom Evolves (Viking Press, 2003). More recently, he discussed the issue on Sean Carroll’s Mindscape podcast.

Related posts:

• Free Will in 1000 words
• “Free will” versus “free won’t”
• Will you choose the cake or the fruit?
• Choosing to hit the baseball
• Bad habits and the Bayesian brain

For additional posts on probability, volition and ethics, follow the Dice icon back or forward where it appears.

Prior   Next