The advances of neuroscience during the last years have given fresh impetus to the search for the material base of consciousness besides fuelling the debate as to what reigns supreme: the brain or the mind, the body or the soul – or are the two mere reflections of each other or, perhaps, one and the same thing?
These questions have occupied philosophers since time immemorial. They underlie the human quest for meaning, which is closely interlinked with that of life and death. Insofar as consciousness is about having an internal perspective, it is unsurprising that we should occasionally wonder how that comes to be and whether it goes on existing, in some or another form, after the body disintegrates.
But before that question is answered – and that might take some time – it is first important to explore how our body, in this case our brain, enables consciousness.
The biggest part of Christof Koch’s book Consciousness; Confessions of a Romantic Reductionist is devoted to the brain sciences and what they reveal about the nature, location, degree and scope of consciousness. Below a summary of the most interesting research findings he reports about:
- Brain science uses the term ‘quale’ to refer to the feeling of experience that is elicited by consciousness. For years, research had focused on mapping experiences to specific brain regions. This turned out to be a dead end. Experiences cannot be clearly mapped to brain regions. Rather, they appear to be network specific.
- At the same time our brains display extreme capability at specialization. Thus we apparently use different parts for capturing the gist of a scene, i.e. its overall character, as opposed to its details. Then again we have concept cells which are extremely particular or concrete in their approach – for instance, we have brain cells for recognizing our favorite film stars.
- Parts of our brains are in charge of integrating information. In doing so, they fulfill an enabling function. This is the case of the thalamus and hypothalamus and possibly of other regions as well. When such regions are lost through brain damage consciousness may be impaired to a significant degree.
- Attention-demanding tasks are performed by the pre-frontal cortex, which also plays a role with respect to learning. Once we have internalized knowledge our brain tends to shift processing to the cerebellum. This applies to automatic sensor-motor activities like moving our hands; but possibly also to social biases or set psychological mechanisms or re-actions.
- For such actions experiments have shown that our brain precedes our sense (or quale) of agency. This is called ‘readiness potential’ and implies that our brain ‘knows’ our intentions before we do – a finding that could also mean there is no free will, and a source of both fascination and exasperation for a romantic reductionist like Christof Koch.
- This said, the ability of our brain to transform what it considers fixed knowledge into routine, automated, and, seemingly unconscious, procedures is also what explains virtuoso performances in sport, the arts and, even, in science.
Christof Koch is of the opinion that the theory that best explains these findings is Giulio Tononi’s integrated information theory, according to which consciousness is a measure of our brain’s combined ability to both integrate and differentiate information. The integrated information theory also implies that all sentient beings possess consciousness to a certain degree; and likewise computers and the World Wide Web. What the integrated information theory does not explain as of yet is the unconscious – since unconscious processes, like automated behaviors or feelings, are quite complex without necessarily being synergistic.
It is in this latter respect that Christof Koch and his colleagues would stand to gain from paying more attention to the mind sciences (as opposed to the brain sciences), namely psychology and psychoanalysis. The mind sciences, as well as psychiatry that operates at the interface between brain and mind, have produced a wealth of knowledge on the mechanisms of both conscious and unconscious processes and about how these are more diverse than they are uniform. Combining the knowledge of these different disciplines, or to use Tononi’s terms, integrating their information, will bring science further, not least by providing a reference framework for formulating hypotheses.
Ultimately – who knows? – it might even turn out that the holy grail of consciousness is, in fact, the unconscious.