Lorraine,
My son, Spencer, used to have episodes when he was younger that looked very much like seizures. He used to stare and would be unresponsive with dilated and non-reactive pupils. He had 2 EEGs that were both normal. It was determined that for him, although his reflux didn't cause seizures, it did cause low oxygen levels during sleep which they feel were the cause of the staring etc. Has your son had an EEG to check for a seizure disorder? If not, it may be a good place to start.
Patti