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panpsychism It is the belief that consciousness is found throughout the universe, not only in humans and animals, but also in trees, plants, and bacteria. Panpsychists argue that some aspects of the mind are present even in elementary particles. The idea that consciousness is pervasive is appealing to many for intellectual and perhaps emotional reasons. But can it be tested empirically? Surprisingly, maybe it could. This is because one of the most popular scientific theories of consciousness, integrated information theory (IIT) shares many, if not all, features of panpsychism.
as an American philosopher Thomas Nagel something is conscious if there is “something like being” in the situation it is in. A waking human brain feels like something specific.
HTE denotes a unique number labeled with the Greek letter φ (pronounced), which is integrated information of the system. fi). If φ is zero, the system does not feel anything; in fact, the system does not exist as a whole because it is completely reducible to its constituent components. The larger φ, the more conscious and irreducible the system is. Given an accurate and complete description of a system, the IIT estimates both the quantity and quality of its experience (if any). IIT estimates that humans have high φ values because of the structure of the human brain, animals have smaller (but positive) values, and classical digital computers almost do not.
A person’s φ value is not fixed. It increases with the development of the self in early childhood and may decrease with the onset of dementia and other cognitive disorders. φ fluctuates during sleep, enlarges during dreams, and shrinks in deep, dreamless situations.
IIT begins by identifying five real and essential characteristics of every conceivable conscious experience. For example, experiences are definite (exclusion). This means that an experience is not less than it is (experiencing only the sensation of the color blue, but not experiencing the moving ocean that brings the color to mind), not more than it is (for example, being aware while experiencing the ocean at the same time). canopy of trees behind). In a second step, the IIT derives five associated physical properties that any system (brain, computer, pine tree, dune) must exhibit in order to feel like something. A “mechanism” in IIT is anything that has a causal role in a system; this could be a logic gate in a computer or a neuron in the brain. The IIT says that consciousness arises only in systems of mechanisms with a certain structure. To simplify it a bit, this structure must be maximally integrated – it cannot be accurately described by dividing it into its constituent parts. At the same time, it must have cause-effect power over itself, that is, the current state of a particular mechanism should limit future states of the system as a whole, not just that particular mechanism.
Given a precise physical description of a system, theory provides a way to calculate φ of that system. Technical details on how this is done complicated, but the bottom line is that in principle one can objectively measure φ of a system as long as there is such a precise definition. (We can calculate the φ of computers because we fully understand them once we have built them. Calculating the φ of a human brain is still an estimate.)
Discussing the nature of consciousness may sound like an academic exercise at first, but it has real and important consequences.
Systems can be evaluated at different levels – a sugar cube-sized portion of my brain, or my brain as a whole, or me and you together. Similarly, the φ of a silicon atom, a particular circuit on a microchip, or an assembly of microchips that make up a supercomputer can be measured. According to the theory, consciousness exists for systems where φ is maximum. It exists for all such systems and only for such systems.
The φ of my brain is greater than the φ of any of its parts, but it sets out to subdivide it. So I am conscious. But my and you together φ is less than my φ or your φ, so we are not “common” conscious. However, if a future technology could create a dense communication hub between my brain and your brain, then such a brain bridge would create a single mind scattered across the four cortical hemispheres.
Conversely, φ of a supercomputer is less than φs of any circuit that composes it, so a supercomputer – no matter how big and powerful – is not conscious. The theory predicts that even if some deep learning systems could pass the Turing test, it would be a so-called “zombie” – simulating consciousness, but not actually conscious.
So, like panpsychism, IIT recognizes consciousness as an intrinsic, fundamental property of reality, and this is common in the graded and possibly tree of life, because any system with a nonzero amount of integrated information will feel like anything. This does not mean that a bee is feeling obese or making weekend plans. However, when a bee returns to its hive loaded with pollen in the sun, it can feel a little bit of happiness. When a bee dies, it stops experiencing anything. Likewise, even a single cell with which millions of proteins interact can feel like a tiny thing, given the immense complexity.
Discussing the nature of consciousness may sound like an academic exercise at first, but it has real and important consequences. Most obviously, how we think about vegetative people is important. Such patients may moan or move for no reason, but fail to respond to commands to signal purposefully by moving their eyes or shaking their head. Are conscious minds trapped in their damaged bodies able to perceive but not respond? Or are they unconscious?
It is misleading to evaluate such patients in terms of the presence of consciousness. Proponents of IIT have developed a procedure that can test consciousness in an unresponsive person. They first set up a network of EEG electrodes that can measure electrical activity in the brain. Then they stimulate the brain with a soft magnetic pulse and record the echoes of this pulse. They can then calculate a mathematical measure of the complexity of these echoes, called the perturbational complexity index (PCI).
PCI is always above a certain threshold in healthy, conscious individuals or people with brain damage but clearly conscious. On the other hand, if healthy people are asleep, their PCI is below this threshold (0.31) 100% of the time. Therefore, it makes sense to take PCI as a proxy for the existence of a conscious mind. If the PCI of someone in a persistent vegetative state is always measured as below this threshold, we can safely say that this person is not secretly conscious.
This method is being investigated in a number of clinical centers in the USA and Europe. Other tests attempt to confirm the predictions that IIT makes about the location and timing of sensory consciousness footprints in the brains of humans, nonhuman primates, and mice.
Unlike panpsychism, the surprising claims of IIT can be tested empirically. If they stop, science may have found a way to untie a knot that has puzzled philosophers since philosophy has existed.
Christof Koch He is the lead scientist for the MindScope program at the Allen Institute for Brain Science in Seattle.
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