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Surprising Science

Consciousness: The Black Hole of Neuroscience

“Consciousness of course is one of the largest questions of brain structure and function. And we approach it now perhaps differently than we have in the past with our new tools. But I’m not convinced that we understand it any better,” says Joy Hirsch.  

What’s the Big Idea?


“By the word ‘thought’ (‘pensée’) I understand all that of which we are conscious as operating in us.” –Renee Descartes

The simplest description of a black hole is a region of space-time from which no light is reflected and nothing escapes. The simplest description of consciousness is a mind that absorbs many things and attends to a few of them. Neither of these concepts can be captured quantitatively. Together they suggest the appealing possibility that endlessness surrounds us and infinity is within.

But our inability to grasp the immaterial means we’re stuck making inferences, free-associating, if we want any insight into the unknown. Which is why we talk obscurely and metaphorically about “pinning down” perception and “hunting for dark matter” (possibly a sort of primordial black hole). The existence of black holes was first hypothesized a decade after Einstein laid the theoretical groundwork for them in the theory of relativity, and the phrase “black hole” was not coined until 1968.

Likewise, consciousness is still such an elusive concept that, in spite of the recent invention of functional imaging – which has allowed scientists to visualize the different areas of the brain – we may not understand it any better now than we ever have before. “We approach [consciousness] now perhaps differently than we have in the past with our new tools,” says neuroscientist Joy Hirsch.

“The questions [we ask] have become a little bit more sophisticated and we’ve become more sophisticated in how we ask the question,” she adds – but we’re still far from being able to explain how the regions of the brain interact to produce thought, dreams, and self-awareness. “In terms of understanding, the awareness that comes from binding remote activities of the brain together, still remains what philosophers call, ‘The hard problem.'”

What’s the Significance?

Discovering how mechanistic processes work – the firing of neurons or the earth revolving around the sun, for example – is considered by some to be an “easy” problem because it involves observation, the description of an event from a third person point of view. “Hard” problems, on the other hand, involve first person experience. They’re the questions that persist even after physical processes have been mapped and explained.

It’s tempting to see them as universal to humanity, but whether and how they’ve been framed has varied historically. Historians of philosophy have observed there was no ancient Greek word that corresponds to “consciousness,” while the modern Western perspective on consciousness seems to have been developed during the Reformation era – the age of “I think, therefore I am,” and “To be or not to be.” (Hamlet was written around 1600, and Rene Descartes’ Discourse on the Method was published in 1637.)

So there’s no reason to assume that consciousness is eternally inexplicable. However, it may never be explained through neurobiology, says David Chalmers, the philosopher who originally made the distinction. “In so many other fields physical explanation has been successful… but there seems to be this big gap in the case of consciousness,” he says. “It’s just very hard to see how [neurological] interactions are going to give you subjective experience.”

Hirsch sees it more practically. Though functional imaging has not explained where perception comes from, it has important applications for unconscious patients. “The boundaries have been broken a little bit, clinically,” she says. “As we study patients with disorders of consciousness, we can probe their levels of awareness in ways that other traditional ways of asking them to respond.”

It’s no different than any other aspect of the brain that we cannot presently explain, she says:

For example, we don’t understand how the brain creates colors. That’s a perception that is very private – I don’t know that your perception of blue is like my perception of blue, for example. Smells are another one. I don’t know that your perception of the smell of an orange is like mine. These are the hard problems of neuroscience and philosophy that we haven’t made a great deal of progress on.

What do you think? Is the distinction between “hard problems” and “soft problems” useful, or reductive? Does the brain create consciousness? Will we ever empirically understand where it comes from or how it works?


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