NEW YORK – Nobel laureate Dr. Robert Axel recently presented “Sense and Sensibility,” the second of four in the annual Brain Insight Lecture Series hosted by Columbia’s Mortimer B. Zuckerman Mind Brain Behavior Institute and supported by the Stavros Niarchos Foundation (SNF).
The lecture which was presented at Columbia University’s Miller Theater focused on the sense of smell, and while Dr. Axel described cutting edge work that seized the attention of the scientists present, his well thought out presentation peppered with humor was accessible to laypersons in the habit of reading Scientific American the New York Times’ science section.
The talks are offered free to the public “to enhance understanding of the biology of the mind and the complexity of human behavior and each talk features Columbia scientists speaking on a range of topics with the goal of enhancing understanding of the biology of the mind and the complexity of human behavior…they are the scientific cornerstone of the Stavros Niarchos Foundation Teacher-Scholar program, which engages 6-10 high school science teachers from around New York City,” according to the Zuckerman institute’s website.
Dr. Thomas Jessell, who along with Axel and another renowned scientist, Eric Kandel, is co-Director of the Zuckerman Institute, introduced Axel.
Jessell and Axel both thanked SNF, which was represented by co-President Andreas Dracopoulos and staff, including SNF Director of Programs and Strategic Initiatives Stelios Vasilakis.
Jessell declared that “everything good that is happening about Columbia came from the fusion of intellect and standards set by” Kandel and Axel. The latter’s work resulted in what are known as the “Axel Patents,” which for many years earned the University $100 million per year.
For his intellectual introduction Jessell said Axel “is not a systems neuroscientist…he is a molecular biologist at heart…seeking clear answers to well-defined questions.”
On that night, Axel asked, “How is it that the richness of the world, which consists of discrete physical parameters – wavelengths of light in vision, frequencies of sound in hearing, the chemicals of smell in taste – all can be recognized and represented in the brain, which simply consists of one thing neurons… which can only vary in two dimensions: they can only change their firing in time and space.”
Axel then paused and said “this, I argue, is an astonishing problem.”
Axel framed the discussion by expressing the continuing wonder of scientists at how the brain enables human beings to experience the richness of reality, which he illustrated by presenting two artistic treatments of the same theme, a depiction of “the earth’s first lovers with a snake” – Adam and Eve.
After the audience viewed the treatment a German Renaissance artist Lucas Cranach, they saw the rendition of modernist Barnett Newman 500 years later.
“Newman has Adam and Eve reflected by lines, colors, forms that bear no resemblance to reality. This is an abstraction. A meaning is imposed upon this painting by prior knowledge of experience. This is precisely what the brain must do” with perception, emotion, cognition, memory.
“All must be represented in a brain by the activity of large ensembles of neurons…and these ensembles lead to neural representations reflecting thought, and so they too must be abstractions, and meaning must be imposed upon these abstract brain representations” – patterns of nerve cells firing.
The noted that “meaning may be imposed either by evolution – instincts, which is crucial for animal survival – “or experience,” which leads to learning, which predominates in guiding human life.
WHAT DOES A BAT KNOW?
He inserted a philosophical parenthesis to the description of brain processing that followed. “This idea of an abstract representation of the sensory world in the brain immediately implies to me that different species, and at the extreme, different individual within each species, will represent the world in different ways, “he said.
Among his fascinating points was that bats, snakes, dogs, and people perceive, and thus “know” radically different worlds.
Axel noted that reality is what our sensory apparatus – which provides information from the bottom up – and other brain processes that work from the top-down, present to us.
The crucial point, at the core of half a millennium’s battles among philosophical schools, is that bottom-up functioning, “is a process that is incomplete. It comes without meaning…which must be imposed… upon the initial representation… by other brain structures – top-down processing.
He explained “meaning is imposed by bringing a stored record of experience, emotion, expectation.
The story of the growth of scientific understanding of the human mind includes deep thinking, imaginative experimenting, and the coming on stream of ever-more amazing imaging, neuron manipulation, and gene research technology, which Axel conveyed t by describing research about how the behavior of our relatively close relatives in the animal kingdom, mice, is governed by instinct and experience encoded in the brain.
Scientists are now able to shut down some areas of the brain such as cortical amygdala, which has a key role in processing emotions and memory, and in decisionmaking, to see exactly what they contribute to experience.