Direct Brain-to-Brain Thought Transfer: A High-Tech Fantasy That Won’t Work

By Bbenzon @bbenzon

New working paper. Title above, abstract, contents, and introduction below. Download at:
Abstract: Various thinkers (Rodolfo Llinás, Christof Koch, and Elon Musk) have proposed that, in the future, it would be possible to link two or more human brains directly together so that people could communicate without the need for language or any other conventional means of communication. These proposals fail to provide a means by which a brain can determine whether or not a neural impulse is endogenous or exogenous. That failure makes communication impossible. Confusion would the more likely result of such linkage. Moreover, in providing a rationale for his proposal, Musk assumes a mistaken view of how language works, a view cognitive linguists call the conduit metaphor. Finally, all these thinkers assume that we know what thoughts are in neural terms. We don’t.
Contents
Does it even make sense to wire brains together? 2 Direct Brain-to-Brain Thought Transfer is a High Tech Fantasy that Won’t Work 3
Christof Koch and brain-bridging 3
The brain in two worlds 6
Musk doesn’t understand how language works 8
The hazzards of thinking at the edge of possibility 11
The peril of getting mixed up in your model 12 What’s a thought? 15
The neural code meets Sydney Lamb’s daughter 15
Vygotsky on the development of speech and inner speech 18
Does it even make sense to wire brains together?
It is one thing to feature technology for direct brain-to-brain communication as an element in science fiction. It is another thing to propose that, some day, we’ll actually be able to do it. The former doesn’t require any argument based on what we know about the brain and about fabricating electronic devices. The latter does.
Yet, when people have proposed such technology in reality – I’m thinking of Rodolfo Llinás, Christof Koch, and Elon Musk – the argumentation is thin and focuses on the technology. No one asserts that we have such technology now, but some day, in the indefinite future, surely we will, and then we will be able link people together so that they can share their thoughts directly, brain-to-brain, bypassing ordinary means of communication and interaction. I first considered such ideas early in 2002 in a thought experiment in which I simply assumed we had such technology. I concluded that it would not support brain-to-brain transfer. Brains don’t work in the way such technology requires.
That thought experiment thus taught me to distinguish two reasons for skepticism about the feasibility of direct brain-to-brain thought transfer:
1. we don’t have the technology to establish millions of point-to-point connections between two brains, and
2. the idea is unworkable in principle.
The thought experiment eliminated the first so that I could investigate the possibility of the second. I concluded that the idea is indeed unworkable in principle.
This working paper is in three sections. The first section, “Direct Brain-to-Brain Thought Transfer is a High Tech Fantasy that Won’t Work,” repeats and elaborates on that orignal the thought experiment, drawing on quotations from Christof Koch and Elon Musk to motivate the argument. The second section, “The peril of getting mixed up in your model,” is methodological in character and talks of the difficulty of separating the capabilities of a proposed model of some cognitive or mental phenomenon, such a brain-to-brain communication, and what what knows, as an external observer, about the model. Vague, I know, that’s the nature of the problem, but I think that this vague business about the relation between model and modeller, this is at the heart of why this is such a tricky issue.
The final section, “What’s a thought?” is about what we mean when we talk about thinking, and comes at it from two sides, the problematic use of computation as a metaphor, and language development. The notion of thought is very general, but is for the most part a common sense term for “what happens inside our heads, where we have feeling as well.” Using common sense ideas in technical discussions – and direct linkage between brains is a technical issue even if we grant the existence of the relevant technology – is tricky because the relationship between the common sense ideas and the technical realm needs to be carefully specified. That is not the case in these brain-to-brain proposals.