What is the nature of consciousness, and can it be fully explained by neuroscience?
Of course neuroscience can explain consciousness, but who will believe it? Just as biology is hampered by the fact that much of it is held in squishy bits that don’t survive close examination (see the Cambrian and before), the study of consciousness is hampered by the fact that it seems to be mediated by neural networks that can’t be paused for examination. Neuroscience is enamored by bottom up study and characterization, and as soon as a study leaves the operation of individual neurons, it can get lost.
The other barrier to a neuroscientific view of consciousness is that philosophers and their neuroscience sidekicks have roiled and muddied the waters of consciousness speculation so badly that it’s hard to have a civilized conversation. Many discussions about the neuroscience of consciousness have ended with someone insisting that “we still don’t know where the qualia are kept!” Heaven help anyone who questions whether qualia are even important.
I will summarize one particular explanation that is consistent with neuroscience and psychology. Notice that I didn’t say it is either widely supported or proven, but I find it very convincing.
Chasing the rainbow: The non-conscious nature of being by Oakley, D. A., & Halligan, P. W. (2017).
In this account, consciousness is a side effect of humanity’s most distinguishing feature, our ability to share information via language. Before I can explain what that means, I will first have to disabuse you of the idea that you are a conscious being or that you live life consciously.
One of the striking neuroscience discoveries of the 21st century is that our lives are almost entirely unconscious. All of our cognition and decision making is carried out in the brain without any conscious involvement. This recognition has come about from improved imaging, most notably fMRI, and more opportunities to study highly instrumented brains, mostly non-human, but also human brains as they are prepped for specialized brain surgeries.
Neuroscience has found that decisions are made long (hundreds of milliseconds) before we experience making them. These studies are often reported in the popular press with the accompanying question about whether we have “free will”, but they only really show that what we think of as our conscious lives are really a reflection of our unconscious lives, not what drives our life. We have free will, but it isn’t held by what we think of as our conscious life, which is merely an observer.
One of the most important questions ever is what makes human society and culture work. Oakley and Halligan answer that it is our imperative to share what we are thinking about with others. Humans, uniquely among animals, continuously broadcast what we are thinking to those around us. The evidence is that we co-evolved this need to share along with the capability of language, and each is dependent on the other. They call this broadcast our personal narrative.
Our personal narrative is shared with whomever is around us, first to our family, then to the tribe, and occasionally to the village. This narrative is how our ideas, inventions, mental states, and plans become public knowledge and benefit the family, tribe and village. The narrative acts as a social lubricant, insuring that most difficulties are resolved by discussions rather than conflicts. The narrative provides our cultural memory since it is shared between people of different ages, allowing ideas to flow through the generations. The narration allows inventions because it allows people to build on the ideas of others. The narration usually leads to stable families and tribes because it makes sure that important issues are widely known, a process often referred to as gossip.
The personal narrative comes directly from each human brain, without conscious involvement, and one of the people that hears the narrative is ourselves, the very person who is broadcasting this narrative. We don’t really need to hear our own personal narrative; it can’t possibly tell us anything that we don’t already know, but there is no way we can’t hear it. What comes out of our mouths must necessarily be perceived by us.
Our own personal narrative is what we identify as conscious thought. Our brain decides what to broadcast to the world, and it also decides what we will hear. Most of us hear in our conscious thoughts more than is broadcast to the world. What we experience as conscious thought is what would be broadcast to the world if we had no filter, and the brain learns as part of growing up what should be broadcast to the culture we live in and what should just be kept to ourselves.
The problem with consciousness arises when we confuse the artifactual listening process with the process of living our lives. When you are walking down the street, or doing anything else for that matter, our brains are making the decisions associated with placing our feet and avoiding obstacles. At any time we can notice the movement of our legs and feet to do these things, but they usually happen quite well when we don’t. Most of the time when we have a conversation, the words just come out without us constructing sentences and their meaning consciously. Sometimes talking is difficult, but that’s because the conversation is difficult for our brain, not because our conscious perception is involved with talking. We are noticing the personal narrative hundreds of milliseconds after decisions are being made.
I will digress to point out that this is what Buddhism and other wisdom traditions have been teaching for thousands of years. The voices that are talking to us in our heads are not us; they are projections that often confuse us.
Other 21st century studies in neuroscience have been finding that our understanding of how the brain works has been entirely upside down, meaning that the brain creates its own model of reality and is not just responding to its senses. I talk about that here and in my Quora space The Predictive Brain.
