Are Brains Analogue or Digital?

college_high_bartlesvilleBartlesville High School formerly known as College High School

Brain science is like particle physics. Progress in particle physics has been very slow because the experiments are very expensive and the technology is very difficult. It takes decades to design and build a particle collider at the energy frontier. Despite the recent advances in mapping the neurology of the brain, progress in understanding brain function has been very slow as well because we are clueless about the nature of the mind.

This post was inspired by a recent talk given by the legendary physicist Freeman Dyson who will celebrate his 91’st birthday on Dec 15. In his talk titled “Are Brains Analogue or Digital?” he touched on many subjects related to brain science. The question of “Are Brains Analogue or Digital?” is not new. Scientists were discussing it decades ago, and without knowing their efforts we were discussing the same question in 1977 as college freshmen. There has been little progress in brain science since 1977. We are still clueless!

Before I get to to the question of “Are Brains Analogue or Digital?” a little background first. The year was 1977.  I had spent August and  September 1977 as an AFS exchange student in Bartlesville, Oklahoma. I was supposed to stay in Bartlesville during the 1977-78 school year and attend the College High School but I was forced to return to Istanbul in early October. During summer 1977, before I went to Bartlesville, I had already been admitted to Bogazici University. My father was supposed to take care of the registration details in September. This unusual process – father waiting in lines and registering the son – was done by many parents of AFS exchange students in the past. Bogazici University was used to that unusual procedure but for some inexplicable reason the registrar refused to register me in my absence. My father called the family I was staying with in Bartlesville and told them that I had to come back. Well, I had another option. I could stay in Bartlesville and take the university entrance exam in 1978 again but I felt that my chances of getting into Bogazici University in 1978 would be lower because I would be softened academically at an American high school having too much fun. Someday I may write more about my experiences in Bartlesville. I have very good memories from Bartlesville. I always remember my host family with love, respect and gratitude.

I returned to Istanbul in early October, 1977.  I passed the English proficiency test so I could register directly as a freshman. Incoming freshmen have to go through intensive ESL (English as a second language) classes for 1 year before they can start taking the regular freshmen classes at Bogazici University.

bogazici_universityBogazici University

When I was a freshman I used to participate in various discussion clubs. In one of these sessions we were discussing whether the human brain is analogue or digital. All five of us were electrical engineering students and we were familiar with the digital computer conceptually. In 1977 no one had a personal computer in Turkey. I saw one in Bartlesville. Father of my AFS-brother was a PhD chemist working for the Phillips Petroleum Company. He bought an Apple personal computer in September 1977. He was very proud to show it to me. I was awe-struck by the beauty and functionality of that earliest personal computer.

bogazici_university_hisardanBogazici University (Image credit)

My fellow EE (electrical engineering) students were absolutely sure that brain works as a digital computer. They knew very little about digital computers and they knew almost nothing about the brain. How could they be be so sure? As a 17 year old college freshman I knew nothing about the human brain either but I knew intuitively that brain could not be functioning as a digital computer.

In electrical engineering the term “analogue” refers to devices that work by taking advantage of specific physical laws. Analogue devices are special designs manipulating nature. The “digital computing paradigm” on the other hand is independent of nature in the sense that we can employ different physical laws to implement the “bit.” The bit represents the “yes/no” (1 or 0). The “digital computing paradigm” is built on the “bit.” The “analogue” device, on the other hand, is totally dependent on the specific functioning of the physical laws it is employing. Analogue device is unique. Function of an analogue device cannot be decomposed into bits (yes/no parts) but interestingly the function of an analogue device can be modeled by a digital computer. There is a subtle difference here.

In parentheses, I should mention that the emerging “quantum computing paradigm” is a marriage of the “analogue” and the “digital.” The “quantum computing paradigm” is “analogue” in the sense that it takes advantage of a specific physical law – quantum physics. The “quantum computing paradigm” is also “digital” in the sense that it has the concept of a “qubit” similar to the concept of “bit” of digital computing.

In 1977, as a 17 year old college freshman I had no idea about quantum mechanics but I sensed that brain was taking advantage of special physical laws. In that sense it had to be “analogue” because the term “analogue,” by definition,  refers to special designs manipulating nature. In those days I was not thinking that the special physical law effective in the brain was quantum mechanics but I was thinking that there was an unseen subtle (almost physical) dimension in the brain and most of the brain functionality was happening in this unseen dimension. After 37 years I still think the same way. Indian philosophers called that (almost physical) unseen dimension “citta.” We know almost nothing about “citta” but this situation will change in the 21’st century. We will know more about the citta.

In his talk, Freeman Dyson uses the term “digital” in a broader sense. By “digital” he usually means “discrete components” or “discrete variables” and by “analogue” he refers to continuous variables or processes. He thinks that “mathematical maps” should be included in the “analogue” category.

In this talk he brings our attention to the following

  • Dynamic Quantum Clustering techniques are very promising in converting data into information and then converting information into knowledge.
  • We have no idea how our memories are encoded and later retrieved so fast.
  • Evolution: songs enhanced fitness
  • Quantum Analog Computing vs. Quantum Digital Computing
  • Brain may be an amplifier – amplifying information encoded at
    the molecular level into neurological signals

Prof Freeman Dyson | Are Brains Analogue or Digital?


About Suresh Emre

I have worked as a physicist at the Fermi National Accelerator Laboratory and the Superconducting Super Collider Laboratory. I am a volunteer for the Renaissance Universal movement. My main goal is to inspire the reader to engage in Self-discovery and expansion of consciousness.
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