The 'brain as receiver': comments on Steven Novella's post

(An improved and updated version of this essay has appeared in my book Brief Peeks Beyond. The version below is kept for legacy purposes.)

A radio receiver. Source: Wikipedia.

As my readers know, in Chapter 2 of Why Materialism Is Baloney I discuss the 'filter hypothesis' of mind-brain interaction. According to this hypothesis, 'no subjective experience is ever generated by the brain, but merely selected by it according to the perspective of the body ... This selection process is akin to a 'filtering out' of conscious experience: like a radio receiver selecting, from among the variety of stations present concurrently in the broadcast signal, that which one wants to listen to, all other stations being filtered out.' (p. 40) Clearly, the 'filter hypothesis' can be referred to as the 'receiver hypothesis,' since it compares the brain to a radio receiver. Due to several subtleties that escape the scope of this essay, I prefer the term 'filter,' but will acquiesce to the 'receiver' description here in the interest of brevity and simplicity.

This week, Michael Prescott referred extensively to my defence of the 'receiver hypothesis' in his latest blog post. As it turns out, not so long ago a reader had also posted on my Facebook page a link to an article neurologist Steven Novella recently wrote attempting to rebut the hypothesis. The 'synchronicities' seem to be suggesting that I write something about it, so I will attempt to de-construct Novella's position here. I encourage you to read this essay to the end, for there are nuances and turns in my position that you may not expect at first.

As my readers know, my use of the 'receiver hypothesis' is metaphorical. The hypothesis, if taken literally, entails dualism: consciousness as one kind of 'stuff' and the brain (that is, the 'receiver') as another, fundamentally different kind of 'stuff.' I do not subscribe to dualism: my position is what philosophers call 'monistic idealism,' as summarised in an earlier essay and short videos. In a nutshell, I think consciousness and the brain are of exactly the same kind of 'stuff', but I think the brain is in consciousness, not consciousness in the brain. More on this below. For now, I want to comment on Novella's article as if I were a proponent of the literal interpretation of the 'receiver' hypothesis. I want to do this to illustrate what I believe to be the clear weaknesses of Novella's argument. This is important because, as we so often see, materialists tend to argue arrogantly as though they had the rational and empirical high-ground. As Robert Perry brilliantly put in a comment to an earlier post in this blog, 'underneath every argument for materialism is the implicit or explicit statement that materialism occupies the privileged default position, so that it gets the benefit of all doubt.' This is what I want to counter in the first half of this essay. In the second half, I will confess that my own position is, in fact, not so far from Novella's own, but with a big twist...

Novella's argument

Novella summarises his two arguments against the 'receiver' hypothesis as follows:

it does not explain the intimate relationship between brain and mind, and (even if it could) it is entirely unnecessary

He elaborates on the second point first:

When I flip the light switch on my wall, the materialist model holds that I am closing a circuit, allowing electricity to flow through the wires in my wall to a specific appliance (such as a light fixture). That light fixture contains a light bulb which adds resistance to the circuit and uses the electrical energy to heat an element in order to produce light and heat.

One might hypothesize, however, that an invisible light fairy lives in my wall. When I flip the switch the fairy flies to the fixture where it draws energy from the electrical wires, and then creates light and heat that it causes to radiate from the bulb. The light bulb is not producing the light and heat, it is just a conduit for the light fairy’s light and heat.

There is no way you can prove that my light fairy does not exist. It is simply entirely unnecessary, and adds nothing to our understanding of reality. The physics of electrical circuits do a fine job of accounting for the behavior of the light switch and the light. There is no need to invoke light bulb dualism.

The same is true of the brain and the mind, the only difference being that both are a lot more complex.

This sounds compelling at first sight, doesn't it? Yet, it is a completely hollow and misleading metaphor: unlike the solid physics behind electrically-powered lighting, we do not have a causal model for how the brain generates consciousness. In fact, we don't even have coherent hypotheses. The whole power of Novella's metaphor resides precisely in the suggestion that we have for consciousness a causal model like we have for electric lighting. But that is false. You see, it is solely because of the existence of causal models for electric lighting that he can say that light-fairies are unnecessary. We simply cannot say the same about consciousness given the complete absence of any remotely equivalent model for how the brain generates mind. The cogency of Novella's fairies is purely rhetorical and, ultimately, hollow and misleading. It brushes over the elephant in the room: the hard problem of consciousness.

Novella goes on, elucidating his first point now:

The examples often given of the radio or TV analogy are very telling. They refer to altering the quality of the reception, the volume, even changing the channel. But those are only the crudest analogies to the relationship between brain and mind.

A more accurate analogy would be this – can you alter the wiring of a TV in order to change the plot of a TV program? Can you change a sitcom into a drama? Can you change the dialogue of the characters? Can you stimulate one of the wires in the TV in order to make one of the on-screen characters twitch?

 Well, that is what would be necessary in order for the analogy to hold.

The idea, of course, is to suggest that we can 'change the plot' of our conscious experiences by fooling around with brain wiring; that we can change our life from 'a sitcom into a drama' by messing around with the brain; that we can 'change the dialogue' of the people around us by hacking our heads. Well, can we? Here is what he says next:

As we have learned more and more about brain function, we have identified many modules and circuits in the brain that participate in specific functions. ...

Disruption of one circuit, for example, can make someone feel as if their loved-ones are imposters, because they do not evoke the usual emotions they should feel.

Disruption of another circuit can make a person feel as if they are not in control of a part of their body – so-called alien hand syndrome.

A stroke that leaves the ownership module intact but unconnected to the paralyzed limb can rarely result in a supernumerary phantom limb – the subjective experience of having an extra limb that you can feel and controlled (but that does not exist).

Seizures are also a profound area of evidence for the mind as brain theory. Synchronous electrical activity in particular parts of the brain can make people twitch and convulse, but also experience smells, sounds, images, feelings, a sense of unreality, a sense of being connected to the universe, an inability to speak, the experience of a particular piece of music, a sense of deja vu, or pretty much anything you can imagine. The subjective experience depends on the part of the brain where the seizure occurs.

Well? What about changing the plot of our lives by manipulating the brain? What about changing our lives from sitcom to drama? What about inserting dialogues into our conscious experience by hacking the brain? Where is the evidence for all that? Clearly, Novella is using a misleading rhetorical device here. He appeals to a strong and valid intuition at first by making an implicit promise. Then, very subtly, he 'forgets' entirely to deliver on that promise. The trick is that readers may not be critical enough to notice it when they read on. They may stay with the conclusion evoked by the original promise, failing to see that it wasn't fulfilled in the end.

What the evidence does show is that brain hacking (for lack of a better expression) can cause incoherent or limited hallucinations (which Novella refers to when he talks about the brain-induced experience of 'smells, sounds, images, feelings.'). These are a far cry from induced 'plot changes' from 'sitcom to drama.' Moreover, the 'receiver' analogy can easily deal with incoherent or limited hallucinations as well, as anyone who ever messed around with the tuning knob of a radio will know. Other observations Novella refers to can also be accommodated by the 'receiver' analogy. For instance, someone's inability to feel connected to loved ones can be interpreted as the 'filtering out' (or 'tuning out') of the experience of love, which is not a mere detail of our conscious lives but a major 'channel.' One can think of it as limiting the range of the tuning knob along a certain dimension, so one can no longer tune into the 'heart channel.' (Here I anticipate that Novella, if he replies to this, will pick on this very specific statement and create a straw-man... just watch.)

His next misleading point:

If, on the other hand, the receiver model were correct then it would be reasonable to predict that as we investigate the relationship between brain function and mental function in greater and greater detail, the physical model would break down. We would run into anomalies we could not explain, and it would seem as if the brain does not have the physical complexity to account for the observed mental complexity. None of this is what we find, however.

Very smoothly, he is passing for a fact the claim that we don't find those anomalies. One can only conclude this by ignoring all the evidence that contradicts materialism. There are plenty of anomalies. I refer to Chapter 2 of my book Why Materialism Is Baloney for a list.

In conclusion, I think the power of Novella's arguments depends on misleading rhetorical devices. I won't even claim that he is purposefully misleading; on the contrary: I actually think that he honestly believes what he wrote. Once you become too invested in a certain paradigm of thought (as any militant materialist is), you also become unable to step back and evaluate the arguments objectively. You drink your own poison and then go on to sell it as elixir; very sincerely.

Where I agree with Novella

All this said, I actually think Novella does suggest some good points, buried in his misleading rhetoric. Here is a part I like:

A dedicated dualist might still argue that each specific mental function requires its own specific receiver. Brain circuits are receiving specific signals. If you stimulate the circuit it acts as if it is receiving the signal. Eventually, this argument leads to a brain that has all the circuitry necessary to produce everything we can observe about mental function – it leads to the light fairy argument, where the light fairy is simply not necessary.

Indeed, beyond a certain level of granularity, if we can keep on deactivating or stimulating more and more specific cognitive capacities by brain manipulation alone, the 'receiver' analogy breaks down. The 'receiver' model entails that brain activity correlates with experience at the finest levels of granularity, but not that brain hardware has the same level of correlation. Of course, the question is: have we passed that level?

My own position

As my readers know, I think materialism's postulate of a whole universe beyond the only carrier of reality we can ever know – that is, conscious experience itself – is inflationary and unnecessary. Materialism simply isn't skeptical enough, entertaining unreasonable metaphysical abstractions as it does. My claim is that only subjective experience exists. As such, the brain is in consciousness, not consciousness in the brain. Anything beyond consciousness is, by definition, beyond knowledge and concreteness, since both knowledge and concreteness are (qualities of) experience.

How do we then explain the fine-grained correlations between brain activity and subjective experience? Because the brain is the visible image of a localisation of the flow of consciousness, like a whirlpool is the visible image of a localisation of the flow of water. For exactly the same reason that a whirlpool doesn’t generate water, the brain doesn’t generate consciousness. Yet, obviously, the image of a process correlates very well with the inner-workings of the process. Flames, as the 'outside view' of the microscopic process we call combustion, correlate very well with the 'inside,' microscopic view of combustion. Yet, flames don't cause combustion; they are simply the way combustion looks from the outside. In exactly the same way, brain activity doesn't cause subjective experience; it is simply the way subjective experience looks from the outside. The simplicity of this interpretation is so self-evident that I find it baffling that materialists don't see it.

Fine, but how do we then explain why physical intervention with the brain can so dramatically interfere with cognition and motor control? For the same reason that a thought can interfere with an emotion. Is there any problem with that? Of course not. After all, a thought is merely a process in consciousness that interferes with another process in consciousness – namely, an emotion. Under monistic idealism, all physical objects, actions, phenomena, and processes are images of processes in consciousness; what else could they be? As such, there is absolutely no problem in the fact that physical intervention in the brain – a process in consciousness – interferes with cognition – another process in consciousness. Seeing a problem here implicitly assumes dualism.

Notice that Novella appeals frequently to parsimony: dualism is unnecessary, because we can explain things without postulating a 'soul' or 'spirit.' I agree with him. But what I find striking is his – and most materialists' – inability to see how their own position makes unnecessary postulates: namely, a whole darned universe outside experience and, as such, beyond knowledge. Parsimony is necessary, and that is precisely why materialism cannot be considered the best explanation for the mind-body problem.

I am aware that what I say above isn't, by any stretch of the imagination, complete enough to tackle all possible objections. That's why I wrote a 250-page book to make my case in a more complete manner. In addition, I have addressed the most common objections to my position in the video below. Please have a look at least at this video before posting your objections in the comments section below.

You might now ask: why do I like the 'receiver' or 'filter' metaphor at all, if I am not a dualist? Because it has much intuitive explanatory power, is closer to reality than materialism, and because it is indeed a proper metaphor for my position: if the brain is a kind of 'whirlpool' of mind, a whirlpool does 'filter out' of itself the water molecules that do not fall within its vortex. A process of mental localisation is, in a way, a process of mental 'tuning.' Dualism may ultimately be wrong, but it surely is a more apt metaphor for the true nature of reality than materialism.