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12/02/2019
Workings of the Brain
CHAPTER 109 Storing Words and Thoughts
On a recent Sunday afternoon (November 24), I was reading my December issue of Discover magazine and was intrigued by an article by Jonathon Keats titled "The Shape of Thought". Keats, who calls himself a "conceptual artist", describes an experience back in 2003, when he underwent what's known as functional magnetic resonance imaging (fMRI) on his brain at the hands of neurologist Bruce Miller of the University of California, San Francisco. I was especially interested in the article in view of my hallucinatory experiences during and following an MRI of my brain some time ago (see my column of 5/20/2018 in Archives). What Keats and Miller were attempting was to see if there were patterns in the MRI images that could be associated with Keats' thoughts of truth and beauty. That same Sunday evening, I watched 60 Minutes on TV and there was Lesley Stahl with a segment on "mind reading" and fMRI studies of the brain by Marcel Just of Carnegie Mellon University and David Brent at the University of Pittsburgh, my old stomping grounds when I was in graduate school at Pitt and I often walked over to what was then the Carnegie Institute of Technology to eat dinner. (Carnegie Tech served meals on plates while at Pitt we ate off metal trays.)
What fMRI does is track the blood flow in the brain through the interaction of the iron in the hemoglobin in the blood with the magnetic field of the MRI machine. Keats says that back in 2003, when he first had an fMRI, the images were notably unimpressive, with scant detail. However, since that time the magnetic fields in MRI machines have gone up in strength quite significantly, as has the number of workers engaged in studies of the brain using fMRI. In his quest for the brain's response to his thoughts of the words truth and beauty, Keats was led to the work of Jack Gallant, a neuroscientist at the University of California, Berkeley. I Googled Gallant and was truly impressed by what he and his coworkers have done.
For one thing, they put people in an MRI machine and had them relax while listening to recorded episodes of Moth Radio Hour. I think I've only listened to one or two of these Moth programs. I am astounded by what these researchers managed to accomplish next. They took the recordings of the programs word by word and matched the blood flow patterns in the brains of the subjects with the individual words as they were spoken. A major finding of this research is that each word is stored in more than one place in the brain! In other words, when a particular word is heard, neurons fire in perhaps three specific locations in the brain. Gallant and colleagues have created a map of the brain showing the locations where almost a thousand common English words are stored. When Keats met Gallant he asked about the words truth and beauty and, sure enough, Gallant could tell Keats that beauty is stored in regions of the brain associated with visual and sensory concepts while truth is stored in regions representing social concepts. (After watching part of the recent CNN program on Trump's lies, I'm wondering if Trump's brain is lacking or is damaged in the truth regions.)
After watching the 60 Minutes program with Lesley Stahl's segment, I realized there is a much more serious reason to scan someone's brain than just to find the storage places of truth and beauty. The fact that David Brent occupies an endowed chair in suicide studies at Pitt provides a clue. Suicide rates among veterans and among young people, including college students, have been rising significantly, so much so that suicide is a factor contributing to a decline in longevity in the United States. Here's where Marcel Just's work at Carnegie Mellon comes into play. Just, instead of using fMRI to study the storage of words in the brain, wondered about patterns in the brain associated with thoughts. For example, a 60 Minutes producer underwent fMRI and was told to have thoughts of disgust and envy. A computer was then instructed to look at the fMRI patterns and correctly identified the emotions of disgust and envy. Well, David Brent had been to a lecture by Just on the Carnegie Mellon work. Brent wondered if Just could look into the brains of people contemplating suicide and the answer was yes.
A key to such studies on suicide involves two areas of the brain, one area emphasizing thoughts of self, the other area thoughts of others. From his work at Pitt, Brent had access to individuals known to have thought of suicide or even some who had attempted suicide but lived. When some of these individuals were placed in the MRI machine and were told to think of the word "carefree", the area of the brain emphasizing others lit up (showed more blood flow) while the area devoted to self did not, or at least much less blood flow. The implication here is that those contemplating suicide can't imagine themselves being carefree but could imagine others to be carefree. On the other hand, the opposite happens when the suicide=prone individuals were placed in the MRI machine and told to think of a word like sad. In such cases the self region of the brain would light up strongly compared to the others region of the brain. In the non-suicidal subjects the opposite would occur.
Obviously, the conclusion of these studies is that fMRI is a promising tool to identify those who are in danger of ending their lives, where intervention treatment could possibly save lives. Unfortunately, mass screenings of individuals using MRI machines is an expensive and cumbersome process. You can be sure that the search for a cheaper and simpler method of looking at specific areas of the brain are or will be underway soon.
The use of computers to look at brain scans of different types and identify correctly thoughts and feelings, not to mention where individuals words are stored shows how far artificial intelligence (AI) has come. We've seen how machines like IBM's Watson have learned to beat world class champions in chess and poker and computers have entered the medical field in areas of diagnosis and remote surgery. As I approach my 92nd birthday this month, I can't help marveling at the fact that I've lived in a time when what I consider Nature's greatest invention, the human brain, has itself been used to invent or develop the instruments and theories to explain the actual origin of our universe, to explore our local region of the universe, to invent the global positioning system (GPS) and the ridiculously small phones that permit us to use that system and see and speak with people anywhere on Earth and to now begun seriously to find out how itself, the brain, really works.
Finally, with the recent passing of my wife of 68 years, I am left to face the probable end of my own life in the not too distant future. While I am not suicidal, I find myself quite accepting of the possibility that the end could come soon or that I could live a few more years, hopefully not to 100. What I'm trying to get at is that in my dotage I'm finding it harder to come up with a column on a monthly schedule and from now on will not post columns on any schedule. See you sometime in 2020, which promises to be a memorable year indeed! Happy holidays.
Allen F. Bortrum
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