The Mother of Invention:

One Researcher’s Unorthodox Approach to Human Cognition

J.E. HUBBARD JR.

Permanent Fellow of the Hagler Institute for Advanced Study

In 1982, as a newly minted assistant professor at MIT in the mechanical engineering department, James Hubbard was given the charge by his department head, Herb Richardson, to develop new tools and techniques for vibration control in modern structures. It was the Reagan Star Wars era, and large space structures were being designed as space-based radar antennae that could monitor and protect entire states from the incoming threat of adversarial ICBMs.

The problem was that such structures had to be very lightweight to make them viable for space launch. The resulting structures vibrated profusely upon deployment and exhibited densely packed modes of vibrations, the likes of which had never been seen before. The conventional approach of actively suppressing the vibrations by using state-of-the-art sensors and actuators resulted in structures too heavy to be viable. Hubbard conceived, designed, and demonstrated a new approach that used a very lightweight piezoelectric polymer as embedded sensors and actuators capable of damping all subsequent modal vibrations in lightweight, flexible structures. He dubbed them “smart structures” because they could sense/actuate structural systems to adapt themselves to the vibration environment for effective control.

The concept went viral, and today the well-established field called smart structures is practiced by engineers worldwide. In fact, the concept of smart systems has become ubiquitous over many fields and applications and has touched our everyday lives.

In 2016, the impact of Hubbard’s early work was recognized through his induction into the National Academy of Engineering. He was the first in the field of smart structures to be awarded such an honor. During the next several decades, Hubbard used that technique to develop new applications in optics, vibrations, medical devices, and the like and was awarded two dozen patents as proof of the uniqueness of his methods.

In 2017, while he was serving on the faculty of the University of Maryland, Hubbard’s wife, Adrienne, suffered a mild stroke that left her with little to no short-term memory. She could not hold a conversation for more than 60 seconds or so. Frustrated with conventional drug treatments, he began to research the problem on his own. He then came upon a company called Freer Logic whose tagline was “We can read your mind.” He called the founder of the company, Pete Freer, and they discussed the problem of diminished short-term memory. Peter indicated that his company’s technology could be effective in mitigating the problem by using brain wave skin sensors and targeted software that exercised the relevant cognitive centers in the brain to rebuild the neural structure responsible for memory. During that period, Hubbard decided to join Texas A&M University under the Texas Governor’s University Research Initiative, which could offer Hubbard the freedom and resources to refocus and pursue research into human cognition and decision-making. After joining the mechanical engineering faculty at Texas A&M, he brought Peter Freer to Texas to meet Adrienne firsthand and recommend a program of rehabilitation. Using the technology of Freer Logic diligently for 12 months, Adrienne regained 95 percent of her short-term memory function. But there was still that 5 percent that seems to involve the brain’s higher-level executive functions: those responsible for planning, execution, and decision-making. As Hubbard gained more understanding of cognition, he learned that neuroscientists largely agree that decision-making is strongly influenced by emotion and that emotion can be reflected in brain wave patterns via EEG measurements. He wondered whether those brain waves behaved similarly to the vibrational waves he had studied for four decades. In other words, could the engineering tools of system identification and modal analysis be used to model and understand human cognition? Hubbard and his students began to work with the modal analysis professionals at the company Brüel and Kjaer to adapt those tools for use in EEG analysis with great success. The brain was treated as a black box with unknown inputs, and the technique of operational modal analysis was used to develop a canonical state space model and complexity plots of EEG data that imaged the modes and mode shapes directly. The researchers defined those modes as eigen-emotions and applied the technique to the DEAP public database of some 1,500 brain wave patterns of 32 subjects stimulated with 16 emotional stimuli. Using the eigen-emotions and a neural network classifier, the researchers matched subjects to a random selection of brain waves from the database with 100 percent accuracy, thus proving the efficacy of the technique. Just as with smart structure analysis, the eigen-emotions formed a mathematical basis set in Hilbert space, thus allowing the use of modern linear algebra analysis. The long-term goal was to explicitly relate eigen-emotions to human decision-making and cognition.

It was then that Hubbard became aware of the works of Busemeyer and Bruza, which related quantum models of cognition to decision-making. Those models were “quantum-like” in their nature and operated in a Hilbert space informed by Schrodinger’s equation and quantum probability. Those models appeared to be able to handle the uncertainties of human emotion and cognition.

For example, human reaction to stimulation is noncommutative in the sense that when people are subjected to ordered stimuli, emotional response depended highly on the order in which the stimuli were presented. Other observed phenomena such as entanglement and collapse could also be used to gain an understanding of human cognitive response. Although Hubbard does not believe that the brain operates as a quantum machine, he does believe that the theory of quantum probability is a useful tool for analysis. Hubbard recruited a strong team to Texas A&M, including Mark Balas, an internationally known researcher well versed in quantum theory, to form what Hubbard now calls the Center for the Hopelessly Naïve to pursue his new approach to quantifying and understanding the human decision-making process. The modal nature of brain waves and their stimulation by light and sound has been recently exploited by researchers at MIT to treat Alzheimer’s disease in mice, and that approach may have implications for other diseases such as Parkinson’s. One scientist’s quest to restore his wife’s memory may now lead to new methods that could help many more.