The Ego Tunnel: The Science of the Mind and the Myth of the Self

by Thomas Metzinger

The problem of consciousness is all about subjective experience, about the structure of our inner life, and not about knowledge of the outer world.

An Ego Tunnel is a consciousness tunnel that has evolved the additional property of creating a robust first-person perspective, a subjective view of the world. It is a consciousness tunnel plus an apparent self.

What is really happening is that the visual system in your brain is drilling a tunnel through this inconceivably rich physical environment and in the process is painting the tunnel walls in various shades of color. Phenomenal color. Appearance. For your conscious eyes only.

Subjective color constancy is a fantastic feature of human color perception, a major neurocomputational achievement.

(In philosophy, we call this game epistemology—the theory of knowledge. We have been playing it for centuries.)

the flow of experience certainly exists, and cognitive neuroscience has shown that the process of conscious experience is just an idiosyncratic path through a physical reality so unimaginably complex and rich in information that it will always be hard to grasp just how reduced our subjective experience is.

The shadow metaphor suggests Book VII of Plato’s Republic. In Plato’s beautiful parable, the captives in the cave are chained down at their thighs and necks. They can only look straight ahead; their heads have been shackled in a fixed position since birth. All they have ever seen of themselves and of one another are the shadows cast on the opposite wall of the cave by the fire burning behind them. They believe the shadows to be real objects. The same is true of the shadows cast by the objects carried along above the wall behind their heads. Might we be like the captives, in that objects from some outside world cast shadows on the wall in front of us?

Might we be shadows ourselves? Indeed, the philosophical version of our position on reality developed from Plato’s myth—except that our version neither denies the reality of the material world nor assumes the existence of eternal forms constituting the true objects of those shadows on the wall of Plato’s cave. It does, however, assume that the images appearing in the Ego Tunnel are dynamic projections of something far greater and richer.

Conscious experiences are full-blown mental models in the representational space opened up by the gigantic neural network in our heads—and because this space is generated by a person possessing a memory and moving forward in time, it is a tunnel. The pivotal question is this: If something like this is taking place all the time, why don’t we ever become aware of it?

Our conscious experience of the world is systematically externalized because the brain constantly creates the experience that I am present in a world outside my brain.

an external world does exist, and knowledge and action do causally connect us to it—but the conscious experience of knowing, acting, and being connected is an exclusively internal affair.

Conscious experience can thus be seen as a special global property of the overall neural dynamics of your brain, a special form of information-processing based on a globally integrated data format.

Consciousness is a large-scale, unified phenomenon emerging from a myriad of physical micro-events. As long as a sufficiently high degree of internal correlation and causal coupling allows this island of dancing micro-events in your brain to emerge, you live in a single reality. A single, unified world appears to you.

Conscious states could be exactly those states that “metarepresent” themselves while representing something else. This classical idea has logical problems, but the insight itself can perhaps be preserved in an empirically plausible framework.

In conscious visual processing, for example, high-level information is dynamically mapped back to low-level information, but it all refers to the same retinal image.

Conscious information seems to be integrated and unified precisely because the underlying physical process is mapped back onto itself and becomes its own context.

If you are conscious, the overall process of perceiving, learning, and living creates a context for itself—and that is how your reality turns into a lived reality.

Could deep meditation be the process, perhaps the only process, in which human beings can sometimes turn the global background into the gestalt, the dominating feature of consciousness itself?

namely that the fundamental subject/object structure of experience can be transcended in states of this kind.

Consciousness is inwardness in time. It makes the world present for you by creating a new space in your mind—the space of temporal internality. Everything is in the Now. Whatever you experience, you experience it as happening at this moment.

The Ego Tunnel is just the opposite of a God’s-eye view of the world. It has a Now, a Here—and a Me, being there now.

The answer lies in the transparency of phenomenal representations. Recall that a representation is transparent if the system using it cannot recognize it as a representation.

INEFFABILITY

introspective identity criteria

maximally determinate value,

Churchland has an original and refreshingly different perspective: If we just gave up the idea that we ever had anything like conscious minds in the first place and began to train our native mechanisms of introspection with the help of the new and much more fine-grained conceptual distinctions offered by neuroscience, then we would also discover much more, we would enrich our inner lives by becoming materialists.

“I suggest, then, that those of us who prize the flux and content of our subjective phenomenological experience need not view the advance of materialist neuroscience with fear and foreboding,” he has noted. “Quite the contrary. The genuine arrival of a materialist kinematics and dynamics for psychological states and cognitive processes will constitute not a gloom in which our inner life is suppressed or eclipsed, but rather a dawning, in which its marvelous intricacies are finally revealed—most notably, if we apply [it] ourselves, in direct self-conscious introspection.”

Only if a world appears to you in the first place can you begin to grasp the fact that an outside reality exists. This is the necessary precondition for discovering the fact that you exist as well. Only if you have a consciousness tunnel can you realize that you are part of this reality and are present in it right now.

The distinction between things that only appear to us and real, objective facts became an element of our lived reality. (Please note that this is probably not true of most other animals on this planet.)

THE WHO PROBLEM: WHAT IS THE ENTITY THAT HAS CONSCIOUS EXPERIENCE?

whereas the relevant oscillation frequencies differ for different structures and in the cerebral cortex typically cover the range of beta- and gamma-oscillations: 20 to 80 Hz. What makes the synchronization phenomena particularly interesting in the present context is that they occur in association with a number of functions relevant for conscious experience.

So what is the essence? Location in space and time plus a transparent body image seem to be very close.

Minimal self-consciousness is not control, but what makes control possible. It includes an image of the body in time and space (location) plus the fact that the organism creating this image does not recognize it as an image (identification). So we must have a Now, plus a spatial frame of reference, and a transparent body-model.

It is inner knowledge, not of ongoing motor behavior or of perceptual and attentional processing directed at the world or single body parts, but of the body as a single multisensory whole, which now becomes functionally available for global control. Conscious selfhood is a deep-seated form of knowledge about oneself, providing information about new causal properties.

So it clearly is the more subtle experience of controlling the focus of attention, which seems to be at the heart of inwardness—selfhood-as-subjectivity is intimately related to “modeling mental resource allocation” as some sober computational neuroscientist might say.

Subjective awareness in this sense of having a perspective by being directed at the world is body image (in space and time) plus the experience of attentional control; inwardness appears when we attend to the body itself.

Having a self-model is like adaptive user-modeling, except that it is self-directed and taking place internally. In an important sense, the resulting Ego is a fiction; however, it is also a wonderfully efficient control device. You could also say that it is an entirely new window on reality.

I claim that phenomenal first-person experience and the emergence of a conscious self are complex forms of virtual reality. A virtual reality is a possible reality.

The brain is like a total flight simulator, a self-modeling airplane that, rather than being flown by a pilot, generates a complex internal image of itself within its own internal flight simulator.

The “pilot” is born into a virtual reality with no opportunity to discover this fact. The pilot is the Ego. The total flight simulator generates an Ego Tunnel but is completely lost in it.

At any given time, the content of bodily experience is the best hypothesis that the system has about its current body state. The brain’s job is to simulate the body for the body and to predict the consequences of the body’s movements, and the instrument it uses is the self-model.

Strictly speaking, and on the level of conscious experience alone, you live your life in a virtual body and not in a real one.

PSM, the phenomenal self-model,

You also need explicit representations of goal-states—your requirements, your desires, your values, what you want to achieve by acting in the world. And you need a conscious Ego to appropriate these goal-states, to make them your own. Philosophers call this having “practical intentionality”: Mental states are often directed at the fulfillment of your personal goals.

No Ego Tunnel, no action.

affordances.

that thinking is a motor process.

Could thoughts be models of successfully terminated actions but from a God’s-eye view—that is, independent of your own vantage point? Could they be abstract forms of grasping—of holding an object and taking it in, into your self?

Broca’s area,

The thinking self would then have grown out of the bodily self, by simulating bodily movements in an abstract, mental space.