How does the brain crack CAPTCHAs?

Speaker: Prof. SP Arun

Abstract

It was famously remarked in the 1980s that a major question for AI is What is the letter A?. Surprisingly, even today, the simple act of recognizing text is so challenging for computers that we continue to use distorted letter CAPTCHAs to validate a user as human. So how does the brain crack CAPTCHAs? In the monkey inferior temporal cortex, an area critical for recognition, we show that single neurons encode distorted letter strings according to highly systematic rules that enable perfect distorted letter decoding. Remarkably, the same rules were present in neural networks trained for text recognition. I will describe this and some related findings elucidating object recognition at the behavioral, neuronal and computational levels.

Bio

SP Arun trained as an electrical engineer, read too much science fiction for his own good and became a neuroscientist. He is fascinated by how the brain transforms sensation into perception, and studies this in his lab at the Centre for Neuroscience, Indian Institute of Science, Bangalore.