1. The first sign is the eyes. When the brain is "creating a picture" the eyes
instinctively move up and to their right (your left), signifying access to the
right hemisphere (creation) and visual cortex (pictures). This usually means
they are constructing a picture in their head. If someone is recalling a picture
(remembering something that they actually saw) then they would look up
and to their left (your right).
2. The eyebrows rising towards the centre of the forehead (where the arrow
lands in the picture) is a sign of fear. This sign can occur during or
immediately after a lie, because they are scared that you will see through it.
3. Another sign of fear is the sides of the lips turning down. The muscles that
control this action are very specific and it is almost impossible to consciously
activate them without activating any other lip-related muscles.
4. When someone touches their nose or lips, covers their mouth or in some
way touches their face during the telling of a lie. It is very common.
Bill Clinton answering question about Monica
Lewinsky in front of the Grand Jury.