Friday, April 22, 2016

Henry Molaison and his “Permanent present tense”

Meditators do years of practice so that they can live in the present moment. Henry Molaison for most of his adult life had no choice but to live in the present moment. As a person with amnesia since the age of 27, he had no concept of yesterday and tomorrow. When asked, “What will you do tomorrow?” Henry answered, “Whatever is beneficial.” Henry Molaison also known as H.M. through the psychology textbooks and literature is the most studied subject in the history of neuroscience. The book “Permanent present tense” by Prof. Suzanne Corkin of MIT whose lab studied Henry as a subject for over 40 years, captures the story of both Henry as well as the neuroscience of memory.

I first heard of Henry when I watched the second episode of the six part PBS documentary “The brain with David Eagleman” titled “What makes me?” Henry underwent a brain surgery at the age of 27 in 1953 as the last option for his sever epilepsy. The surgeon removed both the sides of his hippocampus – a 3 cm component buried deep inside each side of our brain. Henry recovered from his epilepsy but the surgery took away his ability to form long term memories. If you walked out of a meeting with Henry and returned after a few minutes, Henry would greet you as though he is meeting you for the first time. In fact, when researcher Morris left and re-entered the room after some time, Henry said after greeting him, “There’s an empty chair. You go sit there.” That was, of course, the same chair Morris was sitting before he left the room. While being amnesiac Henry was intelligent, articulate and perceptive.

Did Henry lose all types of long term memory? No. One of the breakthrough results in understanding long term memory happened when researcher Brenda Milner administered the star tracing experiment with Henry as the subject in 1963. The procedure involved tracing a five point star by looking in the mirror and it was done multiple times over three consecutive days. The task was challenging and involved learning a new motor-skill allowing a reversed visual image to guide the movement of the hand. Every time Henry began the experiment he had no memory of the previous try. However, Henry’s error rate kept dropping as the first day progressed. His error rate at the start of day-2 was similar to where he left off on day-1. On the third day, He performed nearly perfectly, his pencil rarely crossing the boundary. On day-3, after one of the trials Henry observed, “Well, this is strange. I thought that that would be difficult, but it seems as though I’ve done it quite well”. This showed that Henry hadn’t lost all types of long term memory formation. He had lost what we call episodic memory (What did I eat for breakfast this morning? And with whom?) and semantic memory (What are the names of my friends? Knowledge of people, places). However, he had retained procedural memory (How to use a walker, remote, joystick etc.) When Henry passed away in 2008, he had been using a walker for over a decade.

Henry was mostly an “amiable, smiling” man, but did he ever get upset? Occasionally, he did get frustrated, sad, aggressive or uneasy but these negative emotions would typically dissipate as soon as he was distracted. There were no new associations getting formed that were binding the incident or person or object to an emotion. Perhaps there lies a clue to human suffering – storing a connection between an external situation or person with a negative emotion in the long term memory.  We can carry anger or guilt for years and retrieve it as soon as the link is activated. Henry’s story prompts us to pay attention as we form and retrieve these links every day.

After Henry passed away his brain was scanned in an MRI machine for nine hours. Later it was cut into 2401 ultrathin slices from front to back. These slices have been digitized and assembled into a three-dimensional image that scientists and the public will be eventually view on the web. I liked the way Prof. Corkin concludes the book – Although he lived his own life in the present tense, Henry had a permanent impact on the science of memory, and on the thousands of patients who have benefited from his contributions.

I recommend the book to anyone wanting to understand the development of neuroscience of memory, how experiments are designed in neuropsychology and the role memory plays in our day-to-day life as well as building a narrative called “I”.

Book cover, Henry’s picture are from the book “Permanent present tense”.
Mirror tracing image is from Psychology textbook by Peter Gray.

Friday, April 15, 2016

4 metaphors from David Bohm’s “Unfolding meaning”

Unfolding Meaning” is an edited transcript of a weekend dialogue with David Bohm that occurred in May 1984 in a small country hotel in England. It is similar in spirit with the other seminar Bohm held in Ojai in 1991 and is published as a book “Thought as a system”. However, it is very different in its content especially the dominant metaphors used to communicate the abstract and subtle aspects of our true nature. In this article we look at the 4 metaphors from the book which appealed to me and what they mean.

Thought as a source and the simulation of a program: This is the most dominant metaphor Bohm uses throughout the book. Every thought we have gets stored as a program in a peculiar sort of encrypted form. Unfortunately, our brain doesn’t have the capacity to see that the thought made a program and its subsequent actions are determined largely by that program. Thought is a program that is programmed to conceal itself. When we are thinking, the results of the simulation shows up in the body (hormonal changes, blood pressure, heart beat etc.) and the emotions (anxiety, anger, happiness) but the connection between that and the thought is concealed. In fact, thought attributes the actions of the program to the ‘self’ – a mistake. Bohm says – the attempt to watch one’s own programs is the beginning of a kind of meditation. The picture on the side is from the movie "The Matrix" at a point when the protagonist Neo, for the first time, begins to see the world as a simulation of a program.

Why do I still kick the cat? One of the participants observed, “You can get excited about things like this and then go home and still kick the cat.” Bohm replied, “Why shouldn’t you kick the cat?” If one were really cruel then one would kick the cat and not bother about how it hurt the cat. For those of us who regret the act later, there must be a tacit connection between the cat and oneself. Then the question is – how to see the connection even before I kick the cat? Bohm suggests that it requires attention to your thoughts. When you feel the impulse to kick the cat, you should suspend that impulse. And then you should attentively watch the thought behind it. The thought could be that of frustration (boss shouted at me) or something is not working out (I am doomed). Whatever it is, one should follow that thought and see how it triggers the program of “kicking the cat” automatically.

What to do when I miss the mark: Suppose I am an archer and I miss the mark and I say some evil spirit made me miss the mark. That would never get me anywhere. You have to be attentive as you practice to how you are missing the mark. If you don’t do that then you won’t learn. Every time we have sustained fear or worry or anxiety, it is similar to an archer missing the mark. At that time, if we identify a situation or a person as the cause then it is an incorrect attribution like identifying evil spirit as the cause. Instead what we need is to pay attention to the program that is getting triggered by some thought. 

Seeing beyond Las Vegas lights: Why don’t we see the vastness beyond the world of thoughts? Bohm says following: If you go to a place like Reno, Nevada or Las Vegas and we turn on all these electric lights then you don’t see the stars, and you say that all these lights are the main thing. And there is no universe. They blot out the universe. So when you turn off the lights, then the universe comes through. At first, it seems something very faint, but that faint thing may represent something immense, whereas the very powerful bright thing may represent nothing much.

In short, every thought we have makes or adds to a program which, in turn, determines our subsequent actions. When we kick the cat or when we miss the mark, it is the program that is in action. And we are mostly unaware of it. We are so lost in the thought-world that it blinds us like the lights of Las Vegas. Only when the “lights” are off, do we see the vastness beyond thought-world. When we pay attention to the program in action, it is a kind of meditation.

Related articles:
Matrix as a system vs thought as a system, July 22, 2015 (a presentation)
Metaphors from "Thought as a system", Nov 15, 2015 (a presentation)
Image source: Program snapshot from movie "The Matrix", Archer pic is from