-SAN FRANCISCO R ahul Desikan sits at his dining room table, a large computer screen before him, and works on his lat- est scientific paper. He types a single letter, then another, then another. For a man in a hurry, desperately trying to rid the world of terrible diseases, it's an excru- ciatingly slow process. Using a special mouse strapped to his forehead that detects his smallest movement, Desikan moves a cursor around an on-screen keyboard. When he finds the letter he wants, he clicks a button with his right thumb, and it appears in a white space to the side. Repeating the process over and over, he debates research ideas with colleagues, analyzes reams of data and competes for grants. He types so much that he occasionally wears out the clicker. Moaning softly, he looks toward a caregiver sitting nearby. "Are you thirsty?" she asks. He shakes his head slightly. "Hot?" He makes another low sound, and she loosens his fleece vest and adjusts the neck brace supporting his head. A year and a half ago, this sci- entist's future seemed boundless. He was a rising star at the University of California at San Francisco, a researcher of degen- erative brain diseases. He had just begun the biggest study ever of the genetics of ALS, or amy- otrophic lateral sclerosis, the dis- ease made famous by Lou Gehrig and Stephen Hawking. Then his voice started chang- ing. It got higher and took on an odd nasal quality. He started noticing small muscle twitches in his left arm and weakness in his fingers. ALS was diagnosed five Rahul Desikan, a scientist studying ALS at the University of California at San Francisco, and his wife, Maya, are pictured at their home. Photo: Nick Otto for The Washington Post Ravaged by the disease he studies By Laurie McGinley 31 US-INDIA GLOBAL REVIEW JULY-SEPTEMBER 2018 SCIENCE AND TECHNOLOGY