fact could be a clue to finding if there is a true link between subvocalization and hallucinations, but it is very difficult to see this connection because not many patients experience hallucinations. References External links NASA Develops System to Computerize Silent, 'Subvocal Speech' NASA researchers can hear what you're saying, even when you don't make a sound An interview with NASA's Chuck Jorgensen on the Subvocal Speech - including pictures and video of the technology. Copy at archive.org (no pictures/video): Reading (process) Human communication Educational psychology Learning to read Memory Vocal skills