Is Consciousness Required for Discrimination?

In their book A Universe of Consciousness, Edelman and Tononi use the example of a photodiode discriminating light to illustrate the problem of consciousness:

Consider a simple physical device, such as a photodiode, that can differentiate between light and dark and provide an audible output. Let us then consider a conscious human being performing the same task and then giving a verbal report. The problem of consciousness can now be posed in elementary terms: Why should the simple differentiation between light and dark performed by the human being be associated with and, indeed, require conscious experience, while that performed by the photodiode presumably does not? (p. 17)

Does discrimination of a stimulus from a background “require conscious experience”? I don’t see why it would. This seems like something the unconscious mind could do all on its own and indeed is doing all the time. But it comes down to how we are defining “consciousness”. If we are talking about consciousness as subjective experience, the question is: does discrimination require there be something-it-is-like for the brain to perform that discrimination? Perhaps. But I also don’t know how to answer that question empirically given the subjective nature of experience and the sheer difficulty of building an objective consciousness-meter.

On the other hand, assume by “consciousness” we mean something like System II style cognition i.e. slow, deliberate, conscious, introspective thinking. On this view of consciousness, consciousness is but the tip of the iceberg when it comes to cognitive processing so it would be absurd to say that the 99% unconscious mind is incapable of doing discrimination. This is the lesson of Oswald Külpe and the Würzburg school of imageless thought. They asked trained introspectors from the Wundtian tradition to make a discrimination between two weights with their hands, to see if one weight is heavier than the other. Then the subjects were asked to introspect and see if they were aware of the process of discrimination. To their surprise, there were no conscious images associated with the weight-discrimination. They simply held the weights in their hand, consciously made an intention to discriminate, the discrimination happened unconsciously, and then they were aware of the results of the unconscious judgment. Hence, Külpe and the Würzburg school discovered a whole class of “imageless thought” i.e. thought that happens beneath the level of conscious awareness.

Of course, the Würzburg school wasn’t talking about consciousness in terms of subjective qualia. They were talking about consciousness in terms of what’s introspectable. If you can’t introspect a thought process in your mind then it’s unconscious. On this view and in conjunction with evolutionary models of introspection it seems clear that a great deal of discriminations are happening beneath the surface of conscious awareness. This is how I prefer to talk about consciousness: in terms of System II-style introspection where consciousness is but the tip of a great cognitive iceberg. On Edelman and Tononi’s view, consciousness occurs anytime there is information integration. On my view information integration can occur unconsciously and indeed most if not all non-human animal life is unconscious. Human style slow deliberate introspective conscious reflection is rare in the animal kingdom even if during the normal human waking life it is constantly running, overlapping and integrating with the iceberg of unconsciousness so as to give an illusion of cognitive unity. It seems as if consciousness is everywhere all the time and that there is very little unconscious activity. But as Julian Jaynes once said, we cannot be conscious of what we are not conscious of, and so consciousness seems pervasive in our mental life when in fact it is not.

Book notice: Lancelot Whyte's The Unconscious Before Freud

[Editorial note: “Book notices” will be a new type of post on this blog where I give brief summaries of books I have recently read]

Whyte convincingly argues for the thesis that “the general conception of unconscious mental processes was conceivable (in post-Cartesian Europe) around 1700, topical around 1800, and fashionable around 1870-1880.” Whyte’s aim is to show that, contrary to popular opinion, Freud did not “invent” the concept of the unconscious. In fact, the concept had been percolating in the general intellectual atmosphere for quite some time prior to Freud. Whyte employs a heavy battery of quotations from a diverse array of sources, most of the whom I had never heard of before. Although Whyte’s own understanding of psychology is rather dated and has a lighter significance compared to those he is quoting, his historical scholarship is top notch and surely represents a significant amount of time scouring libraries, a feat even more impressive given Whyte published the book in 1960 well before the advent of internet research.

Initial thoughts on David Eagleman's new book Incognito: The Secret Lives of the Brain

I just purchased David Eagleman’s new book Incognito: The Secret Lives of the Brain and I like what I’m reading so far based on the first chapter. What immediately strikes me about Eagleman’s ideas is that his understanding of consciousness is very Jaynesian. Compare these two paragraphs:

“Reactivity covers all stimuli my behavior takes account of in any way, while consciousness is something quite distinct and a far less ubiquitous phenomenon. We are conscious of what we are reacting to only from time to time. … We are continually reacting to things in ways that have no…component in consciousness whatever.”

“Brains are in the business of gathering information and steering behavior appropriately. It doesn’t matter whether consciousness is involved in the decision making. And most of the time, it’s not. Whether we’re talking about dilated eyes, jealously, attraction, the love of fatty foods, or the great idea you had last week, consciousness is the smallest player in the operations of the brain. Our brains run mostly on autopilot, and the conscious mind has little access to the giant and mysterious factory that runs below it.”

Which quote is which? It’s hard to tell isn’t it? (Answer: the first is Jaynes, the second is Eagleman). Eagleman seems to be arguing for an essentially Jaynesian thesis: consciousness is not ubiquitous in the daily life of humans (and almost entirely absent from many of our animal cousins, as well as newborn infants), it flickers in and out, hovering over the surface of the deep unconscious ocean, occasionally getting access to the abbreviated, filtered, narratized version of information that consciousness operates over and then feeds back into the unconscious system.

In one of his most lively metaphors, Eagleman likens our conscious mind to a newspaper. Imagine all the economic, social, and political activity that is going on in the world at any given time. It would be impossible for anyone to gather or comprehend all that information. So what do we do? We read a newspaper filled with headlines and articles that condense that mountain of information into digestible, easy to understand bites. The reader uses the newspaper to gather useful information without bogging down in the huge complexity of reality. But Eagleman points out that we are curious readers, for we read the headline and take credit for coming up with the thought ourselves. As Eagleman puts it, “You gleefully say, ‘I just thought of something!’, when in fact your brain performed an enormous amount of work before your moment of genius struck. When an idea is served up from behind the scenes, your neural circuitry has been working on it for hours or days or years, consolidating information and trying out new combinations. But you take credit without further wonderment at the vast, hidden machinery behind the scenes.”

Here’s another takeaway message from Eagleman: “One does not need to be consciously aware to perform sophisticated motor acts.” As I mentioned before, this is an essentially Jaynesian thesis. Just from reading the first chapter, I can already see that Eagleman understands perfectly what conscious is not: it is not at the center of our mental lives when scaled against the entirety of the unconscious mind. It only appears to the conscious mind that it is at the center of the show. This is a firm and convincing neural trick, one very hard to overcome without deliberately or inadvertently tampering with the neural machinery through drugs or worse. The illusion of centrality and “inwards looking outwards” generates a phenomenon of unified experience along with a narrative, autobiographical identity over time. While it is true we have unified conscious experience and sense of conscious self-hood, especially when we reflect on that self, it is true only in the sense that we experience ourselves as having unified experience, but not in the sense that our experience actually is consciously unified. A closer examination reveals that the unified experience is a neurological artifact of consciousness knitting itself over the unconscious mind in the form of “newspaper headlines” i.e. narratives summarized and constructed after the fact. Eagleman uses the example of baseball. A fastball flies from the mound to the batter in 4/10ths of a second. This is far too fast for a narratized headline to be useful in directing behavior. Luckily, the unconscious is quick enough to respond, otherwise no one could ever hit a fastball.

But does this mean that consciousness is a mere epiphenomenon, lagging behind but not exerting any influence of its own? No, not at all. Just because consciousness comes after the fact doesn’t mean that it has no causal effects. Afterall, newspaper headlines have causal force insofar as the consolidated information hits the brain and leads directly or indirectly to new behavior. Imagine you saw a newspaper headline that the world was about the end. This would have instant behavioral effects. Although the headline was generated “after the fact”, it still has causal force insofar as the digestion of that headline by the conscious mind allows for behavioral shortcuts to be made through higher-order categorization and planning. So the fact that consciousness “lags behind” and deludes itself into running the whole show does not imply that it has no effect on the show at all. It does have an effect, a great one actually. But part of the effect is the feeling of being more than just a neurological newspaper. The newspapers wants to think that it is more than just a narratized summary in higher-order packaging.

“Unconscious perception” and the body schema

In this post over at Science and Consciousness Review, Stan Franklin discusses how the dorsal, or “where” stream of visual perception is unconsciousness. In contrast to the ventral stream, which is responsible for the “what”, or object recognition, the dorsal stream is involved with spatial awareness for actions such as grasping.

Franklin cites work from Goodale and Milner that studied a patient with an impaired dorsal stream. After careful experimentation, Goodale and Milner concluded that the dorsal stream is unconscious. Normally, I do not like discussing perception in terms of the conscious/unconscious dichotomy, but I though this conclusion was interesting because of its implications for Shaun Gallagher’s preconscious body schema, that I discussed in this previous post. This body schema is a system of sensory-motor capacities that is responsible for such pre-reflective activities as walking, keeping upright posture, and other motor actions that we do more or less “unconsciously” such as appropriately  molding our grip to reach an object. So, with respect with the unconscious dorsal processing Franklin was discussing, I think the body schema is an appropriate theoretical construction that fits the evidence.

"Unconscious perception" and the body schema

In this post over at Science and Consciousness Review, Stan Franklin discusses how the dorsal, or “where” stream of visual perception is unconsciousness. In contrast to the ventral stream, which is responsible for the “what”, or object recognition, the dorsal stream is involved with spatial awareness for actions such as grasping.

Franklin cites work from Goodale and Milner that studied a patient with an impaired dorsal stream. After careful experimentation, Goodale and Milner concluded that the dorsal stream is unconscious. Normally, I do not like discussing perception in terms of the conscious/unconscious dichotomy, but I though this conclusion was interesting because of its implications for Shaun Gallagher’s preconscious body schema, that I discussed in this previous post. This body schema is a system of sensory-motor capacities that is responsible for such pre-reflective activities as walking, keeping upright posture, and other motor actions that we do more or less “unconsciously” such as appropriately  molding our grip to reach an object. So, with respect with the unconscious dorsal processing Franklin was discussing, I think the body schema is an appropriate theoretical construction that fits the evidence.