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Rob Ennis

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Some history

I feel like providing some history clarifies why I do what I do.

As a youngster, I enjoyed patterns and repetitive things - knitwork, meditation aids, floor & ceiling mosaics, tapestries, gemstones/leaves, chants, etc - and the religions and cultures that surrounded them, even after becoming an atheist in adulthood. I think this was partly how my early interest for computer programming started - branches, iteration, references, function stacks, and naming conventions for variables - and from combinations of these, entire worlds of abstraction could play out in real-time before your eyes. But, my computing interests were also driven by another source of joy at that time - video games. I loved them (and still do, although I rarely play them now; Super Mario was the first!) and as I got deeper into games, I wanted to become a video game programmer. That quickly changed, though. At some point, when asked what I wanted to be when I grew up, I said, "A whale scientist!". That would still be cool to do.

Later, after seeing films like "The Matrix", "Star Wars", "Alien", and "Blade Runner" and reading lots of Sci-Fi books, I got interested in the gritty world of cybersecurity, struggling to understand things like buffer overflow attacks and assembly language. I jumped in a little too deep at the beginning and never developed proficiency in it, but I loved it regardless, and as a result, I became a fan and proponent of Linux/Unix, even becoming a fan of Plan 9. I went through the standard *nix rites of passage, such as my fair share of confusing crashes after changing some options deep in a configuration file; my parents and friends were not fully convinced of this "Linux thing". I thank my parents greatly for their patience with all of my experiments and my varying interests, and their loving support to this day.

As I grew up, my interests and goals continued to change, reaching a point where I was not sure if I wanted to study psychology or physics at university. I started with physics, but by my third year of study, I decided that I did not want to do a career in pure physics. As part of my undergrad liberal arts credits, I took an introductory psychology class, remembering how much I also enjoyed that, so I started a parallel degree in psychology. That landed me in Prof Arthur Shapiro's "Sensation and Perception" class. I took the class because it sounded cool and indeed, it was! On the first day of class, Artie drew a person, a tree, and a sun on the chalkboard. As he drew, he said, "Here, we have a sun, radiating photons that bounce off the leaves of the tree, some of which enter our eyes. And here, we have the brain of this person and if we ask them what they see, they will probably say 'a green leaf'," and he draw a thought bubble and wrote "leaf" inside. He then posed the question, "so, physics out here, psychology in here, and the eyes and brain are the link, but how do we connect all of it?" I thought "Perfect! A wonderful question that brings together physics and psychology; exactly what I want!".

I pursued this field, technically known as "psychophysics". I think most people believe I am rather confused when I say that I am a "psycho-physicist", but I found it incredible that such a field of study existed and that there was a whole branch of science focused on studying color perception. Prof Shapiro kindly let me join his lab, where we worked on developing and investigating optical illusions that tested his filter-based theory of brightness perception and the differences between perception in the fovea and the periphery. With that, our group won the Best Illusion of the Year contest (see illusion here). We had a lot of fun. Prof Shapiro is still a friend and I will always be thankful for the support and understanding he showed. He gave me direction and set me on a great path.

I enjoyed psychophysics so much that I went further with it. My graduate career was happily spent in the lab of Dr Qasim Zaidi, who showed equal care for my work and my well-being. He always had lunch with the lab and provided us with endless feedback (and restaurant recommendations!). We worked closely with Dr Barry Lee, in whose lab I had ample fun and the chance to learn about retinal physiology. Dr Lee is a living example of what it means to be very successful, yet humble and friendly, and also critical in a supportive way. He also always laughed at my jokes. To this day, Qasim and Barry are supportive, patient, kind, and always giving me something new to think about. I am very thankful for that. With Dr Zaidi, we investigated the time-course and neural locus of chromatic adaptation, the effect of microsaccades on the temporal contrast sensitivity function (TCSF), and the geometrical structure of perceptual color space. With Dr Lee, we provided a retinal basis for the slow-phase of chromatic adaptation and the microsaccade effects on the TCSF.

At the end of my graduate career, I was fortunate to receive a Post-Doc position in the lab of Dr Karl Gegenfurtner, which brought me to Giessen, Germany. My time here changed my life in numerous good ways and from Karl, I not only learned ways to keep science simple and clear, but also new dimensions of humor. During my time with Dr Gegenfurtner, I have worked extensively with our Specim hyperspectral camera and have been on projects that investigated the color categorization of natural objects (i.e., autumn leaves) and scotopic lightness perception.

I then transitioned to a Post-Doc position in the lab of Dr Katja Doerschner-Boyaci. Dr Doerschner-Boyaci, always with a smile and a laugh, allowed for a lot of freedom and exploration of experiment ideas, and her encouragement often pushed me off in new directions that I had never tried or considered. As a result, I learned as much about science as I did about myself. Under Katja's guidance, we expanded the study of transparent colors from flat filters to 3-D objects, tested various color constancy metrics in a novel task where observers disentangled the relative contributions of illumination and surface to temporal color changes, and investigated the influence of motion and surface reflectance properties on eye fixation patterns.

Just like in previous labs, both Katja and Karl have been patient, friendly, supportive, funny, and always open to hearing my ideas. I am again very thankful.

I now work simultaneously in close collaboration with Dr Doerschner-Boyaci and Dr Gegenfurtner. Currently, we investigate color constancy across materials in VR, the color appearance of iridescent objects, and methods for studying brightness and color perception in the wild internet. Although we are in a general psychology department, the labs here are quite diverse, with people training deep neural networks, building new display systems, working with virtual reality headsets, and conducting fMRI and EEG experiments.

Nowadays, I am wrapping up my Post-Doc phase and seeking something new. I have made many wonderful, lifelong friendships throughout my psychophysics career and the work has brought me much joy and lots of new ideas, as well as changed my worldview several times. I greatly appreciate the value of expanding our knowledge of the visual system and how it improves the lives of others, but now I would like to take the knowledge and skills that I have developed and apply them to the bioinformatics industry, in order to improve medicine and our global quality of life. We will see where I end up next :-)


Currently, I am in the lab of Dr Karl Gegenfurtner, but I still work closely with Dr Katja Doerschner-Boyaci. These days, I mostly spend my time on the following:

Personal projects

I also have some personal projects that I work on in my spare time:

But only coding, science, data analysis?

No, not only! ;-)

Here is what gives meaning to my life, provides purpose, and keeps me stable in a world that can often feel like a sculpture made of mud: