Interviews of the Future
Then machines will monitor their brains for lies and their speech muscles for unspoken thoughts.
Right now, scientists know that different parts of the brain are activated by lies and honest statements.
And these differences can be measured by functional magnetic resonance imaging (fMRI) scans.
Also, NASA is developing a system that uses two sensors, one on the neck and one under the chin, to monitor electrical signals sent to the speech muscles.
This allows it to work out what people are saying - even if they do not speak out loud.
Sources: here and here.