Research

I am a Ph.D. candidate in Brain & Cognitive Sciences at the University of Rochester where I work with Robbie Jacobs. My ultimate scientific dream is to understand how the brain accomplishes the totality of its perceptual and cognitive abilities, some of which are nothing short of phenomenal, in more or less the way we understand how digital computers do the things that they do. This ambitious goal requires not only breaking up those perceptual and cognitive abilities into smaller and more manageable pieces, abstracting away some of their complexity in the process, but also analyzing each piece at multiple levels of abstraction from a computational (or rational) analysis of the problem involved to the circuit level mechanisms that the brain might be using to solve the problem. My main research interest is thus to understand cognitive and perceptual phenomena using theoretical/computational models at multiple levels of analysis. For this purpose, I borrow ideas and tools from machine learning, particularly probabilistic graphical models, and computational neuroscience. In my current research, I apply this methodology to a specific problem in a restricted domain: encoding multiple items with simple features in visual short-term memory.

Papers

Orhan, A.E., & Jacobs, R.A. (to appear). A probabilistic clustering theory of the organization of visual short-term memory. Psychological Review.

Orhan, A.E., & Jacobs, R.A. (2011) Probabilistic modeling of dependencies among visual short-term memory representations. In J. Shawe-Taylor, R.S. Zemel, P. Bartlett, F. Pereira & K.Q. Weinberger (Eds.), Advances in Neural Information Processing Systems 24. [supplement]

Orhan, A.E., & Jacobs, R.A. (2011). A nonparametric Bayesian model of visual short-term memory. In L. Carlson, C. Hölscher, & T. Shipley (Eds.), Proceedings of the 33rd Annual Conference of the Cognitive Science Society. Austin, TX: Cognitive Science Society.

Orhan, A.E., Michel, M.M., & Jacobs, R.A. (2010). Visual learning with reliable and unreliable features. Journal of Vision, 10(2):2, 1-15. 

Notes

Here are some notes I have written on: Dirichlet processes, particle filtering, the leaky integrate-and-fire neuron. Please send me an e-mail if you find any typos, errors, inaccuracies or grave omissions in these notes.

Links

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I think this is probably the best collection of short stories written in the English language, and this is probably the second best.