It's a small Keystone meeting on the pathophysiology of autistic syndromes here in Santa Fe, New Mexico, but you can feel the excitement among the 100 or so attendees, as they muddle their way through early data in this growing area of research. There are only nine posters being presented today -- but, according to co-host Pat Levitt from the Vanderbilt Kennedy Center, all are important. This is in contrast to the last Keystone I attended on stem cell biology in Whistler, British Columbia, in 2006, which was several times the size, with tens of posters every night. (Interesting, given that autism rates among children have skyrocketed, while the field of stem cell research has so far produced more hype than results.)

So much about autism, a condition marked by socialization problems, remains a mystery - genes vs. environment, one disorder vs. multiple, the role of brain volume, etc.

This morning, Gerry Dawson at the University of Washington described interesting experiments that attempt to elucidate some of the clinical features of autism. In one, scientists reviewed home video tapes taken of children at their first birthdays, and compared features of non-autistic children to those of children who were later diagnosed. In another photo, an autistic boy plays with blocks while a scientist sits across from him and pretends to be hurt and crying, to test how long it takes the boy to notice him, and how long he lingers over the sad scientist. As part of another experiment, the researchers broadcast two sounds: A woman inviting a child to play with her in a soothing voice, and a garbled computer sound with no recognizable words (the autistic children preferred the computer sound).

One set of videos were encouraging: In one, a little girl sits and plays with blocks without looking at the people around her, and makes non-verbal sounds, all hallmarks of autism. After some intensive, early therapy, however, a second video shows the same girl reading, talking, smiling and engaging with those around her. A sign that some of what these scientists are doing may be working.