text:  On the next Radiolab... Now this is the part where Helen learned her first word was. I spent most of my life feeling constricted by Helen Keller's ghost. I don't blame Helen Keller. Did you really have to write that letter? We don't focus on that. It's not in the past. No. The Helen Keller Exorcism. That's next time on Radiolab. Beginning this morning at 10...