How Can We See, Dr. Wiesel? June 3, 2020

Posted by ajoyfulpractice in Uncategorized.
Tags: Alexandra Stéliski, Bear McCreary, Dr. David Hubel, Dr. Gerald Edelman, Dr. Oliver Sacks, Dr. Torsten Wiesel, eyes, ocular plasticity, Pandit Rajmani Tigunait, truth, visual cortex, yoga, yoga philosophy, Yoga Sutra 2.20
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“I stopped explaining myself when I realized other people only understand from their level of perception.”

– Anonymous

 

“‘Every act of perception,’ Edelman writes, ‘is to some degree an act of creation, and every act of memory is to some degree an act of imagination.’”

– Dr. Oliver Sacks, quoting Dr. Gerald Edelman (co-winner of the 1927 Nobel Prize in Physiology or Medicine)  

 

Yoga Sutra 2.20: draşțā dŗśimātrah śuddho’pi pratyayānupaśyah

– “The Seer is the pure power of seeing, yet its understanding is through the mind/intellect.” [Translation by Pandit Rajmani Tigunait (for comparative analysis), “The sheer power of seeing is the seer. It is pure, and yet it sees only what the mind shows it.”]

The beginning of today’s blog post looks like a Saturday blog post. During the Saturday practices, we’ve spent the last year and a half digging deep into the Yoga Sutras, where Patanjali outlines the 8-limb philosophy of Yoga and spends quite a bit of time talking about the mind and how the mind works. The last few weeks (and really most of the quarantine), there has been an emphasis on the “seen” and the “unseen” and how we perceive the world around us (and how the world around us based of those same perceptions). Much of what we’ve been exploring on Saturdays fits in with this week’s theme of how perception connects to ideals.

Remember, what we “see” translates into what we understand (because we can only understand what the mind shows us) and what we understand leads to what we believe, which in turn forms our ideals – and how we live is determined by what we believe. Check to make sure you got that: We live not by what we say we believe (or what we claim are our ideals and values), but by what we actually believe in our hearts. Before, however, we get into the emotional and energetic side of this – before we go deeper into the metaphor of “seeing” – let’s take a step back, and consider how we (literally) visually see.

“The eye and the brain are not like a fax machine, nor are there little people looking at the images coming in.”

 

– Dr. Torsten Wiesel (b. 06/03/1924), co-winner of the 1981 Nobel Prize in Physiology or Medicine

“We’re interested in how the brain works, and we work on the part of the brain that has to do with vision. And we…we record from single cells in the brain, and ask how it is you can influence those cells by shining lights and patterns.”

 

– Dr. David Hubel, summarizing research with Dr. Torsten Wiesel that won the 1981 Nobel Prize in Physiology or Medicine

When Dr. Torsten Wiesel, born today in 1924, started working with Dr. David Hubel in the 1950’s, they were under the impression that animals (people included) saw whole images. By connecting the brain of an anesthetized cat to electrodes which produced a sound when the receptor cells within the visual cortex were activated, they thought they could map the cat’s neural pathways. Eventually they would not only map the cells associated with the visual cortex (and determine the mechanism by which they work), they would also win the 1981 Nobel Prize in Physiology or Medicine for their research on ocular dominance columns. I say “eventually,” however, because they weren’t very successful when they started. Their basic premise was flawed, and it was by virtue of a “lucky” accident that they started making headway (pun intended). This, then, is one of those “aha” or epiphany moments I talk about all the time, where a realization occurs because someone is primed to recognize/understand what they are seeing.

“Science is not an intelligence test. Intuition is important, knowing what questions to ask. The other thing is a passion for getting to the core of the problem.”

– Dr. Torsten Wiesel, co-winner of the 1981 Nobel Prize in Physiology or Medicine

Wiesel and Hubel started off by shining bright lights at the cat, which resulted in no reaction from the electrodes, meaning no reaction from the receptor cells. They then moved on to slides of black dots. The black dots seemed to work – in that the cells fired and the electrodes engaged to produce a sound. However, the cells didn’t seem to fire consistently. When the researchers paid attention to the exact moment the cells fired, they realized the cat’s brain wasn’t reacting to the very pronounced black dot. Instead, the cells deep inside the visual cortex were reacting to the very faint line produced by the edge of the slide as it was moved in and out of the projector.

By experimenting with the placement and angle of lines (of various densities and from various sources), the scientist were able to identify and map “simple cells” and “complex cells.” Simple was the term applied to cells which reacted to lines presented at a specific angle (some cells reacting at one angle, others at another). Complex was the term applied to cells which responded to lines presented at a specific angle and moving in a specific direction. They were also able to determine which cells responded to light versus dark lines, which cells responded to bright versus dim lines, and which responded to lines of different colors and densities. All told, they expand were able to determine that the 125 million rods and cones in each retina sent information to 1 million fibers of optic nerve, which each transmitted signals to a variety of different regions in the brain. Those regions in the brain consisted of over 1 million cables of fibers which transmitted electric signals to additional regions before the signals finally reach the simple and complex cells in the visual cortex (about seven stages beyond the retina). All of this signaling and transmitting happens in the blink of an eye. (Sorry, couldn’t resist.)

As they went deeper, Weisel and Hubel discovered that if they covered one eye in kittens, preventing stimulation, the now dominate eye took over the areas of the brain (and the corresponding cells) which would normally be activated by the opposite eye. However, the cells of these kittens did not develop in the same way as kittens using both eyes. They did not develop binocular vision, which meant they did not see objects 3-dimensionally within their environment – and this lack of development was irreversible, which lead to a deeper understanding of ocular (and brain) plasticity.

“Innate mechanisms endow the visual system with highly specific connections, but visual experience early in life is necessary for their maintenance and full development. Deprivation experiments demonstrate that neural connections can be modulated by environmental influences during a critical period of postnatal development.”

 

– Dr. Torsten Wiesel

 

“We are born with this ability. So, as a newborn, open your eyes, visual system is ready to respond to the outside world.”

 

– Dr. Torsten Wiesel, explaining significance of research that won the 1981 Nobel Prize in Physiology or Medicine

Consider, for a moment, what you (literally and visually) saw as a child. Did you see people from different ethnicities, cultures, religions, and races? Did you see different genders and sexualities? Did you see people of different ages and socioeconomic backgrounds? Did you see people of different heights and weights? Did you see people of different abilities? How did you see these people? And, how did you come to understand these people and how they fit into your world?

These are important questions to ask ourselves, in part, because while science has shown that brains can experience quite a bit of plasticity over a lifetime, change and new neural pathways are only created when we understand what we are seeing/perceiving – and understand that what we are seeing/perceiving is different from what we have seen/perceived/understood before. Additionally, the neural pathways are only hardwired when repeated experiences reinforce the new experience. Ultimately, however, if we don’t have reinforced experiences (or we don’t understand what we are seeing/perceiving) then what is reinforced is our tunnel vision and lack of depth. Confirmation bias, the tendency to interpret new information as confirmation or proof of existing beliefs is tunnel vision and a lack of depth. It can also be a bit of hallucination.

“We see with the eyes, but we see with the brain as well. And seeing with the brain is often called imagination. And we are familiar with the landscapes of our own imagination, our inscapes. We’ve lived with them all our lives. But there are also hallucinations as well, and hallucinations are completely different. They don’t seem to be of our creation. They don’t seem to be under our control. They seem to come from the outside, and to mimic perception.”

 

– Dr. Oliver Sacks in a TED Talk, discussing Charles Bonnet syndrome (a condition where visually impaired people hallucinate)

“I saw people that had been incarcerated and, you know, the whole issue about the rights of people determining their own fate has always been close to my heart.”

– Dr. Torsten Wiesel, discussing his humanitarian efforts as an academic and scientist

Dr. Torsten Wiesel turns 96 today. His career as a scientist, a researcher, and an academic allowed him to be exposed to people from all over the world. And, it seems, he always kept his eyes open. He served as chair of the Committee of Human Rights of the National Academies of Science in the US, as well as the International Human Rights Network of Academies and Scholarly Societies for 10 years. He is a founding member of the Israeli-Palestinian Science Organization, a nongovernmental nonprofit established in 2004 to support collaborative research between scientists in Israel and Palestine. In addition to his many scientific awards and accolades, he was awarded the 2005 David Rall Medal from the Institute of Medicine and the 2009 Grand Cordon Order of the Rising Sun Medal (in Japan).

Please join me today (Wednesday, June 3^rd) at 4:30 PM or 7:15 PM for a practice that’s as much about the brain as it is about the body and the heart. Use the link from the “Class Schedules” calendar if you run into any problems checking into the class. You will need to register for the 7:15 PM class if you have not already done so. Give yourself extra time to log in if you have not upgraded to Zoom 5.0. You can request an audio recording of this practice via a comment below.

Wednesday’s playlist is available on YouTube and Spotify.

“For me ‘plus tôt’ is a piece that talks about the sort of space and time that you’re in before things happen to you. The sort of calm you can feel when you don’t know that some events are about to change you. It’s the beginning of the trip. It’s the beginning of the inscape.”

 

– Alexandra Stéliski explaining the inspiration for the first piece on her album Inscape (the song title translates to “earlier”)

More ocular science…

 

(NOTE: Some blog quotes by Drs. Wiesel and Hubel are from a short biography produced by National Science & Technology Medals Foundation when Dr. Wiesel was awarded the 2005 National Medal of Science.)

 

### I CAN SEE YOU. CAN YOU SEE ME? ###