Mark Solms is coming out with a book on consciousness, which he discusses in a blog post. Solms sees the key to understanding consciousness as affects, specifically feelings, such as hunger, fear, pain, anger, etc. In his view, the failure of science to explain the hard problem of consciousness lies in its failure to focus on this aspect of mental experience. And affects, he states, are generated in the brainstem.
Solms is in a camp of
animal researchers* cognitive scientists, along with people like the late Jaak Panksepp, which see consciousness centered on the brainstem, specifically the midbrain region in vertebrates. He cites as evidence for this hydranencephalic children, children born with most of their forebrain missing, who appear to display affective states, and animals who have been decorticated, who also show signs of affects.
One of the problem with discussing affects, like so many other concepts in the cognitive sciences, is that the word “affect” is ambiguous. For these kinds of situations, I always think there’s value in checking a quality dictionary, since dictionary definitions are based on actual usage. Along those lines, Merriam provides two definitions for the noun version of “affect”:
a: a set of observable manifestations of an experienced emotion : the facial expressions, gestures, postures, vocal intonations, etc., that typically accompany an emotion
b: the conscious emotion that occurs in reaction to a thought or experiencehttps://www.merriam-webster.com/dictionary/affect
I think this encapsulates the problem in a nutshell. Under normal conditions for healthy humans, a: and b: virtually always happen together. So when we see cases of a:, it’s completely natural for us to project b: onto what we’re seeing.
The problem is we know from human brain injury cases that b: happens in the forebrain. Someone with damage in the connections between their insula and anterior cingulate cortices can feel pain without being bothered by it. There can be similar injuries knocking out someone’s ability to feel fear. They might even have the physiological reactions associated with these states, but simply not have the associated feeling. If damage in the forebrain can knock out the conscious experience of an affect, then the feeling of the affect happens there, not in the midbrain.
Yet, as Solms notes, we have cases of a: in children with little or no forebrain or animals who have had their cortex removed. It’s actually widely acknowledged that reflexive reactions originate in the midbrain. (In mammals, a lot of reflexive reactions also originate in subcortical regions of the forebrain.) It’s powerfully counter-intuitive to see the “facial expressions, gestures, postures, vocal intonations” as reflexes that can happen without the experience, but that’s the reality.
Solms is right that affects are generated in the midbrain, at least the more basal ones. But the lion share of the evidence is that it’s not where they’re felt. In summary, when discussing affects, we have the reflex, and we have the feeling caused by that reflex. When assessing evidence for affects, we should be clear which version the evidence actually supports.
But isn’t it possible there are some feelings happening down in the midbrain? The problem is, if there are, we appear to have no introspective access to them. Consider that your midbrain is the region that controls eye saccades, the constant and ongoing movement of your eyes. Yet we have no real conscious perception of this movement.
These are among the reasons most neuroscientists see consciousness as a forebrain phenomenon, specifically a thalamo-cortical one.
Still, Solms is a serious scientist, often cited in many other books I’ve read on the evolution of consciousness. I will almost certainly read his. I’m expecting some good information on animal nervous systems and research, even if I anticipate disagreeing with many of his conclusions.
What do you think? Is Solms right that focusing on affects is the key to the hard problem? Are there aspects of this I’m overlooking?
* Corrected per comment from James Cross.