Kouider et al have recently reported that infants’ cortical activity (when viewing faces) is isomorphic to that of adults who consciously perceive faces. They conclude that conscious perception develops between 5 and 15 months of age. After reading their paper, I want to consider a different conclusion. Perhaps Kouider et al didn’t find a marker of conscious perception. Maybe they found a marker of unconscious perception.
A couple month’s ago, I was at a conference where Anthony Jack proposed a very interesting theory: maybe we have two neural systems (Task Positive Network [TPN] and Default Mode Network [DMN]) that produce conflicting intuitions about some age-old philosophical puzzles. These conflicting intuitions lead us to get stuck when thinking about these puzzles (e.g. the hard problem of consciousness, the explanatory gap, or qualitative consciousness) are the result of conflicting intuitions (Jack et al 2013).
I was struck by Jack’s presentation for two reasons: (1) I was presenting a poster with a similar motivation at the same conference and (2) I have long been interested in a biological examination of (academic) philosophers.
This link is a poster about philosophers’ brains that I presented at the Towards a Science of Consciousness Conference in Tuscon—I gave a talk based on this poster at University of Utah. Use the link to see a full-size PDF that will allow you to zoom ad nauseum without the blurriness—vector graphics are so cool!
We should not be surprised if some of the differences between philosophers views correlate with differences between philosophers’ brains. I list a handful of neurobiological differences that already correlate with philosophical differences among non-philosophers. It’s not obvious what we should glean from the possibility that philosophers’ brains could differ as a function of their views. After all, it might be that studying certain views changes our brain. That would not be surprising or concerning, really. But if it were the other way around — e.g., that structural/functional differences in brains predisposed us towards some views and away from other views — then that might be concerning. What if academic philosophy is just an exercise of post hoc rationalization of the views that philosophers’ brains are predisposed toward? Of course, it’s entirely possible that causation works in both directions. But even that could be concerning because that is compatible with self-reinforcing feedback loops. For instance, perhaps we are neurally predisposed to certain views, so we study those views which further predisposes us toward that view (and away from its alternatives). But these questions are getting ahead of the evidence. Hopefully, the neuroscience of philosophy will provide some answers. Until then, check out the poster to see what questions the research has already answered.
- If Higher order theories of consciousness are true, then prefrontal lesions should produce manifest deficits in consciousness (as defined by HOT).
- PF lesions do not produce manifest deficits in consciousness.
- Therefore, many HO theories are not true.
Liad Murdik, in her comments, adeptly pointed out that the PFC is commonly taken to be a center (location, module, etc.) of HO states by a number of people, but this might be a mistake. She explains: it does not follow from the notion that the PFC is associated with higher order mental capacity (i.e. what makes humans more cognitively advanced than, say, mammals without a PFC) that the PFC is the location of HO thought or states. HO thoughts and states could very well be the product of dynamic relationships between various cortices.
Suppose the following about persons.
- Persons have sensory experiences from certain vantage points
- Persons’ have psychological states
- Sensory experience and psychological states can vary as a function of vantage point
How does this effect personal identity? To put it briefly, it would mean that for one person to be identical with another, then (given Leibniz Law, strictly enforced) the persons would have to be identical according, at least, to the following variables:
- Sensory experience and psychological state(s)
- Vantage point(s)