Criticisms of reductive, computational accounts of the brain are not new, and in fact belong squarely within the set of common philosophical criticisms of neuroscience. Among these criticisms are the claims that we don’t reduce down to our neuronal parts and that “you are not your brain.” Arguments for these positions have historically ranged from positing non-physical spirits to arguing from an explicitly physicalist standpoint, and have been inseparable from the development of psychology and neuroscience. With his recent popular aeon article, decorated psychologist Robert Epstein has become the most recent stirrer-up of this contentious, interdisciplinary pot.
His claim is that the brain does not “contain”. Furthermore, the foundational assumption of cognitive science and psychology is a horribly mistaken “contains + processes” thesis about the brain. Epstein aggressively argues that your brain is not a computer - in reality, or in metaphor.
But does he provide a single good reason why the brain as an information processor is a mistaken metaphor?
Reason number one: We have innate reflexes.
Epstein comes out swinging: his first argument purports to show how “vacuous” the information processing (IP) thesis is.
In short: babies enter the world prepared to interact with it effectively. But, babies are not born with “information, data, rules, software, knowledge, lexicons, representations, algorithms, programs, models, memories, images, processors, subroutines, encoders, decoders, symbols, or buffers.” Therefore, the brain doesn’t store or process anything.
Epstein provides plenty of evidence about the innate reflexes babies have, including the orientation babies have towards faces. But babies don’t have a merely a specific orientation to faces, they have an orientation to 3 contrasting spots. Why couldn’t it be the case that this reflex phenomenon is explained by an innate heuristic for processing stimuli? Why can't that be a computational process?
There is no connection between innate reflexes and the computational realization of these reflexes. This demonstration of vacuousness is just an assumption of Epstein’s main point, not a reason to support it.
Reason number two: Computers code information into bytes. We don’t.
A computer codes information into bytes. These byte patterns represent information. Computers then move patterns place to place. Therefore: “computers really do operate on symbolic representations of the world. They really store and retrieve. They really process. They really have physical memories.” But, concludes Epstein, we don’t do this. Therefore, the IP thesis is wrong.
Nowhere does the IP thesis assert that we represent the world in specific, byte-like patterns. ‘Information’ doesn’t just mean ‘things that are coded into bytes.’ An analog amplifier processes and manipulates information, but by definition doesn’t represent that information in bytes. The nature of information is an enormous question. At the very least, I'm comfortable saying that networks of neurons are just as capable as circuits - perhaps even more capable - when it comes to carrying information.
Reason number three: The IP metaphor will eventually be replaced by a better metaphor or by ‘actual knowledge’.
The middle section of Epstein's article is a succinct and compelling overview of the different metaphors humans have used to think about the mind over the course of our recorded existence. These metaphors all have one thing in common: they are subject to the technology and cultural conceptions of their historical context, and they change when that context changes. Because all of these metaphors were far off base, we can expect that our current metaphors are also subject to change, and we shouldn't get too attached to them.
I don’t want to open a philosophy of science can of worms here, but I see no reason for us to be concerned that our metaphors grow and improve with our context and understanding. I agree that we should not allow the IP metaphor to blind us to other possible empirical explanations.
But what exactly is "actual information"? Are we to understand the brain only in terms of rushes of ions moving in and out of neurons that result in action potentials and a cascade of synapses? Is this what actual knowledge looks like? Abstraction and metaphor will always be a critical part of science, and it shouldn’t be a point against the IP thesis that it is only "the best we have so far."
Reason number four: The IP thesis is based on bad logic.
None of my colleagues would dare to claim that ‘all computers are capable of behaving intelligently.’ It's much more natural to say that the motivation for the IP thesis comes from our ability to model the behavior we've seen from neurons - all the way down to the atomic level.
Reason number five: We can draw a dollar bill better when we have one as a template to work off of.
When we're asked to draw a dollar bill from memory - an object we Americans have seen thousands of times - we do a pretty poor job compared to when we have one to copy off of. What does this failure to reconstruct show? According to Epstein:
“We don’t have a ‘representation’ of the dollar bill ‘stored’ in a ‘memory register’ in our brains... and a thousand years of neuroscience will never locate a representation of a dollar bill stored inside the human brain for the simple reason that it is not there to be found.”
First of all, why would the IP thesis have to hold that any representation is perfect? It is perfectly coherent to hold that our representations of the world are biased, inaccurate, and subject to decay.
Even more concerning is the claim that the IP thesis implies the precise localization of individual representations. Why would the IP thesis be committed to this empirically implausible view? The next reason provided is of a similar form:
Reason number six: Cognitive functions are realized by spatially distributed systems in the brain.
Doing anything with the brain - remembering, emoting, reflecting - always recruits a large and diverse area of the brain. But what bearing does this have on the thesis of information processing? Why can’t information processing happen in virtue of a lot of different distributed components? Put another way, what about the IP hypothesis commits it to a simplistic and specific view of functional localization?
“The idea, advanced by several scientists, that specific memories are somehow stored in individual neurons is preposterous.”
This isn’t advanced by any scientists in the same way no computer scientist advances that an individual jpeg is stored in a particular circuit.
Reason number seven: It is more accurate to say that the brain ‘changes’ rather than the brain ‘stores’.
If the IP thesis is wrong, what alternative does Epstein offer? His alternative model:
“(1) we observe what is happening around us (other people behaving, sounds of music, instructions directed at us, words on pages, images on screens); (2) we are exposed to the pairing of unimportant stimuli (such as sirens) with important stimuli (such as the appearance of police cars); (3) we are punished or rewarded for behaving in certain ways… the brain has simply changed in an orderly way.”
A proponent of the IP thesis could just as well agree with this abstract picture of learning and brain development. To ‘store’ and to ‘process’ imply a physical, neuronal change. The kind of mechanism that gives rise to this change, be it action-oriented perception, reward-punishment stimulus, or associations makes no difference as to the underlying function of neurons, which, according to the IP thesis, is to process information.
Reason number eight: There have been no interesting findings from the IP thesis.
Epstein concludes with a shocking and indefensible claim:
“The IP metaphor has had a half-century run, producing few, if any, insights along the way.”
If cognitive neuroscience has been a slave to the ‘useless’ IP metaphor for so long, it's a rough sell that we've made very little progress in the last half century. What then, should we consider the myriad of clinical applications developed from them, if not insights? I cannot call the enormous amount of human suffering alleviated from the direct clinical application of the IP metaphor anything but a triumph of human progress. If that doesn’t count for an insight, what does?
Given how vehemently I’ve argued in defense of the IP thesis, it may seem surprising that I have my own disagreements with representational views of the mind. At the end of the day, I agree with Epstein that we need a more action-oriented and holistic view of our own brains, but this is no reason to deny that the brain is an information processor. All it gets us is an anti-representationalist picture.
Despite my own personal convictions, none of the arguments offered in ‘The Empty Brain’ are actually problems for the defender of the IP thesis. The day may come when the IP thesis is replaced with a more accurate metaphor, or we may someday gain a new understanding of the mind that seems unimaginable now that precludes the IP thesis, but that day is not today.
Don’t push DELETE just yet.