In late October, Charlie Rose began a 12-part series on the human brain. The second episode is scheduled for airing on PBS stations the week of November 24. According to www.charlierose.com, the topic will be: “The Perceiving Brain – Sight and Visual Perception.”
His guests for the first show included:
- Eric Kandel — co-host of the series, 2000 Nobel Laureate (Physiology/Biology), professor, Columbia University Physiology & Cellular Biophysics
- Cornelia Bargmann — Torsten N. Wiesel Professor, The Rockefeller University
- Gerald Fischbach — executive vice president for Health and Biomedical Sciences and Dean of the Faculty of Medicine at the College of Physicians and Surgeons of Columbia University.
- Anthony Movshon — Presidential Professor of Neural Science and Psychology at New York University and Adjunct Professor of Physiology and Neuroscience at New York University School of Medicine.
- John Searle — Slusser Professor of Philosophy, University of California Berkeley
I’ve posted excerpts from this first episode (below) that I found especially meaningful to my interests. (19:20)
Among the highlights:
CR: New discoveries could someday promote mindfulness, increased cognition, and treatment for disease. (My question: why wait for new discoveries? Why can’t we already apply what we know now to increase “mindfulness” and “increased cognition”? That’s what this blog and my website advocate.)
Kandel: “Mind” is a series of functions carried out by the brain. Every aspect of behavior is carried out by the brain. In the past few years, fields such psychology, philosophy, brain science, molecular biology, have begun to integrate their understanding of the brain/mind. Consciousness: you cannot know or understand directly what is going on in someone else’s brain.
CR/Kandel: The brain is always changing, with each experience. Everything we do makes the brain change to some degree. This helps explain how the brain recovers from damage, it illustrates the plasticity of the brain.
Bargmann: The reason that humans can generate language is because humans have specialized genes that distinguish us from animals, can do things that animals can’t. Humans have approximately 25,000 genes; these genes create the structures and functions of each brain. Regarding differences between genetic and environment influences on brain development, this is the essential question. Some things are exclusively determined by genes (ability to see color), others determined by experience/culture (which language we speak, how well we speak is a function of when we have those learning language experiences).
Searle: How does the brain generate the “qualitative unified subjectivity” of experience and feeling? Every experience we have “is produced by variable rates of neuron firings in the brain.” Consciousness can be commonly defined as: “states of qualitative feeling or sentience or awareness that go on all the time.” Features of consciousness: 1) always special qualitative feel; 2) subjective, personal, goes on in ME; 3) unified, all senses and perceptions integrated into single unified conscious feel.
Kandel: Nerve cells communicate through points of contact called synapses. Short-term memory results in/from a functional change. For longer-term learning or memory (beyond a day) there is a change in the expression of genes, growth of new synaptic connections.
Fischbach: Nerve cells are building blocks of the brain; estimated 100 billion nerve cells/neurons that generate electrical pulses ~ 1/1000 of a second. Many scientists believe that the information in nervous system is somehow encoded in the frequency or the detailed time structure of these impulses. The larger neurons conduct pulses at about 100 mph. Our brains are continually active even when we’re asleep. Brain cells require more oxygen and blood than other cells, consume more energy. Each neuron may have as many as 1,000 connections, resulting in 1,000 x 100 billion synapses. The complexity of the brain lies in how the synapses change as a function of genetic instructions and experience. The brain is not “hardwired.” It is within limits in that there is an architecture to the brain, but on the micron scale there is a great deal of flexibility.
Movshon: The brain is not a computer — it’s “made of meat”, very different from silicon and copper.
Searle: We must respect the brain’s specific biology. The computer metaphor was an impediment that did not recognize the biology of the brain. This analogy reflects an “unintelligent view.” This group respects the anatomical, biological specificity of the brain, not an accidental organ.
Fischbach: Nerve cells are organized into circuits, and larger ensembles of circuits.
Bargmann: One of the miracles of the brain is that an experience, an emotion, a thought, is turned into a biological, physical reality by your brain. How does one brain produce infinitely-many behaviors in response to external and internal stimulations?
Movshon: We have a huge challenge in identifying what level of brain function we’re talking about. The brain is unique as an organ in that there are so many levels of activity; molecular, cellular, cell communication, circuits, areas, lobes; each level of analysis has a level of answer to whatever problem is being discussed.