Koch's Book On Consciousness

I was pleasantly surprised to find this book.  I have been following the work of Guilio Tononi for some time and that involves reading articles co-authored by Christof Koch as one his main collaborators.  There also have several excellent videos available on YouTube where they discuss consciousness and Integrated Information Theory (IIT) of consciousness.  In this book we learn about Koch's personal and professional trajectory in the field and several of his influences.  He is currently the President and Chief Scientific Officer of the Allen Institute for Brain Science and a Professor of Biology and Engineering at Caltech.  His academic credentials are available at the link to his web page and they are reviewed in this book as a backdrop to how he came to the field of consciousness studies.     

The layout of the book is 10 chapters over 166 pages.  It is well written in that it contains technical terms but they are well explained for the novice.  On the other hand there are also higher level concepts pertaining to consciousness that will probably not be obvious to many readers that are well explained and worthwhile reading for anyone who is not an expert in the field.  The text reminds me of a slim guide to neuropathology that one of my med school professors claimed was the only book he studied to pass his subspecialty boards exams.  In other words, the more you bring to a book like this, the more you may take away.  At the same time it is interesting reading for a novice.   

A typical chapter is organized around clinical and scientific observations, associated philosophy and the personal experience and meaning to the author.  I thought about characterizing the writing as a very good blog, but this writing by one of the top neuroscientists of our time is several levels above that.  Koch writes from the perspective of admiration of some of the best scientists in the world when it is clear that he is among them.  He adds a unique perspective referencing his training, his family and social life, and the relationships he has with colleagues and mentors.  In the final chapter he describes how his career and experience has impacted on his belief system and personal philosophy.

I will touch on a couple of examples of what he covers and the relevance to consciousness.  Chapter 5: Consciousness in the Clinic is a chapter that is most accessible to clinicians specializing in the brain.  He briefly summarizes achromatopsia and prosopagnosia or face-blindness.  He discusses prosopagnosia from the perspective of clinical findings and associated disability, but also consciousness.  For example, patients with this lesion do not recognize faces but they do have autonomic responses (galvanic skin resistance) when viewing faces that they know (family or famous people) relative to unknown people.  This is evidence of processing that occurs at an unconscious level that he develops in a subsequent chapter.  He describes the Capgras delusion - as the "flip-side" of prosopagnosia in that they face is recognized but the patient believes the original person has been replaced by an impostor.  In this case the expected increase in galvanic skin resistant is lacking because there is no autonomic response to unconscious processing.

In the same chapter he details the problem of patients in a coma,  persistent vegetative state (PVS) and minimally conscious state (MCS) and how some new developments in consciousness theory and testing may be useful. From a consciousness perspective coma represent and absence of consciousness - no arousals and no sleep transitions.  Persistent vegetative state result in some arousals and sleep-awake transitions.  In the minimally conscious state there are awakenings and purposeful movements. The minimally conscious person may be able to communicate during the brief arousals.  At the clinical level being able to distinguish between the persistent vegetative state and the minimally conscious state is important from both a clinical and medico-legal perspective. He discusses the use of fMRI in the case of apparently unresponsive patients who are able to follow direction to think about very specific tasks and produce the same brain pattern of activation seen in controls.  In a subsequent chapter Tononi and Massimini use transcranial magnetic stimulation (TMS) and electroencephalography (EEG) for the same purpose.  This technique is considered proof of IIT as well as a clinical test to differentiate PVS from a minimally conscious state.  In normal awake volunteers the TMS impulse results in brief but clear pattern of reverberating activation that spreads from the original stimulation site to surrounding frontal and parietal cortex.  The pattern can be viewed in this online paper (see figure 1).  In the patient who is in non-REM sleep there is no cortical spread from this impulse and the total impulse duration is less, illustrating a lack of cortical integration required for a conscious state.  When applied to PVS versus MCS patients, the MCS patients show the expected TMS/EEG response that would be seen in conscious patients.  The PVS patients do not.  He describes the TMS/EEG method as a "crude consciousness meter" but obviously one that probably has a lot more potential than traditional clinical methods.

There are many other clinical, philosophical and scientific issues relevant to consciousness that are discussed in this book that I won't go into.  I will touch on a recurring theme in the book that gets back to the title and that is science and reductionism.  Philosophical perspectives are covered as well as the idea that the origin of consciousness may not be knowable by scientific methods. Koch's opinion is that most everything is knowable by science and that science generally has a better track record of determining what is knowable.  That is certainly my bias and I am on record as being an unapologetic reductionist rather than a romantic one.                           

This is a book that should be read by psychiatrists and residents.  These concepts will hopefully be some of the the mainstays of 21st century psychiatry.  It can be read at several levels.  I was interested in the development of Koch's ideas about consciousness.  I wanted to learn about his relationship with collaborators.  I was pleasantly surprised to learn that we had similar thoughts about popular media, philosophy, and and psychodynamic psychiatry.  I have had career long involvement in neuropsychiatry and behavioral neurology so the description of cortical localization and clinical syndromes was second nature to me.  But even against that background, he makes it very clear where consciousness comes in to play.  One of my concerns about psychiatric training is that there is not enough emphasis on neuroscience and consciousness.  Condensed into this small book there are number of jumping off points.  Each chapter has a collection of annotations and there is a list of about 100 scientific references at the end.  It may take some work, but this book is a brief syllabus on how to get up to speed in this important area and greatly extend your knowledge of how the brain works.


George Dawson, MD, DFAPA


Reference:

Christof Koch.  Consciousness: Confessions of a Romantic Reductionist.  First MIT Press Paperback.  Cambridge, Massachusetts, 2017.  Copyright 2012.   

Attribution:

Figure 1 above used with permission of the publisher.  The complete reference is:

1:  Massimini M, Ferrarelli F, Sarasso S, Tononi G. Cortical mechanisms of loss of consciousness: insight from TMS/EEG studies. Arch Ital Biol. 2012 Jun-Sep;150(2-3):44-55. doi: 10.4449/aib.v150i2.1361. Review. PubMed PMID: 23165870.  Open Access Free Text.