That poor brain of ours. It is sitting “up there in the bony vault of the skull, where there is no light, no sound, no anything; it’s completely dark and utterly silent”. When trying to find our way in the world, all our brains have to go on is a constant barrage of electrical signals which are only indirectly related to things out there in the world. The sensory inputs don’t even arrive with labels announcing their modality”. They don’t tell us whether their source is visual, auditory, touch, or anything else. “What we see hear, and feel is nothing more than the brain’s ‘best guess’ of the causes of its sensory inputs.”
In his fascinating book Being You British neuroscientist Anil Seth puts forward a new theory of consciousness and self. He writes that we humans deal with the world by a process that he calls controlled and controlling hallucination, explaining how the brain cooperates closely with the rest of the body to stay alive and to maneuver through the world in the best possible way.
This is how the process works. First, sensory signals are entering the brain. Then, the brain is making predictions about the causes of these sensory signals. It is continually formulating perceptual hypotheses about the way the world is – based on past experiences and other forms of stored information – and testing these hypotheses by acquiring data from the sensory organs. Subsequently, sensory signals keep these perceptual predictions tied in useful ways to their causes. The signals serve as prediction errors registering the difference between what the brain expects and what it gets at every level of processing. Seth writes that perceptual experiences are determined by the content of the (top-down) predictions, and not by the (bottom-up) sensory signals. “The brain settles and resettles on its evolving best guess about the causes of its sensory environment, and a vivid perceptual world – a controlled hallucination – is brought into being.”
Seth explains that we never experience sensory signals themselves, we only experience interpretations of them. Colour for example is not a definite property of things-in-themselves. Rather, “it is a useful device that evolution has hit upon so that the brain can recognize and keep track of objects in changing lighting conditions. When I look at a red chair, the redness I experience depends both on properties of the chair and on properties of my brain. It corresponds to the content of a set of perceptual predictions about the ways in which a specific kind of surface reflects light.” There is no redness-as-such in the world or in the brain; perceptual experiences don’t directly correspond to things that have a mind-independent existence. “The entirety of perceptual experience is a neuronal fantasy that remains yoked to the world through continuous making and remaking of perceptual best guesses, of controlled hallucinations.”
So the brain has no direct access to anything in the outside world. Nor does it have direct access to any physiological states inside of our body. Inside and outside these states have to be inferred through best guessing, achieved through a brain-based process of prediction error minimisation.
Interoception is perception of the body from within. “The key property of interoceptive signals is that they reflect how good a job the brain is doing of keeping the body alive.” In the same way that redness is the subjective aspect of brain-based predictions about how some surfaces reflect light, emotions and moods are the subjective aspects of predictions about the causes of interoceptive signals. They are internally driven forms of controlled hallucination. Emotions and moods can be understood as control-oriented perceptions which regulate the body’s essential variables. “This is what they are there for” and this is what Seth calls ‘controlling hallucination’. Emotions and moods “are intimately and causally bound up with how well we are doing, and how well we are likely to do in the future, at the business of staying alive.” The primary goal for any organism is to continue staying alive. This is why the brain exists, Seth writes.
Furthermore, Seth writes that action is inseparable from perception. Perception and action are so tightly coupled that they determine and define each other. Every action alters perception by changing the incoming sensory data, and every perception is the way it is in order to help guide action. “There is simply no point to perception in the absence of action.” We perceive the world around us in order to act effectively within it, to achieve our goals and – in the long run – to promote our prospects of survival. “We don’t perceive the world as it is, we perceive it as it is useful for us do to so.”
These subjective realities become relevant for leaders when they are connected into intersubjective realities, as explained in Yuval Noah Harari’s latest book. These are powerful stories that are created, shared and repeated by people. Laws, gods, nations, corporations and currencies exist in the nexus between large numbers of minds; they are conjured into existence through shared narratives. All relations between large-scale human groups are shaped by stories and myths that are constantly confirmed, challenged and revised. Seth sticks in his book to the individual perspective.
“All of our perceptions and experiences, whether of the self or of the world, all are inside-out controlled and controlling hallucinations that are rooted in the flesh-and-blood predictive machinery that evolved, develops, and operates from moment to moment always in light of a fundamental biological drive to stay alive.” We are “conscious beast machines”, living systems actively modelling our world and our body, so that the set of states that define us as living systems keep being revisited, over and over again.
Anil Seth. Being You. A New Science of Consciousness. Faber & Faber, 2021