Taking note of eye gestures is a natural and important part of communication process. While evaluating body language close attention to eye gaze, eye movement, blinking and pupil size can help better understand messages. Just like other forms of gestures they allow individuals to communicate their feelings and thoughts non-verbally. They can be accompanied with other body language and words as well.
As a result of studies and observations of people of various cultures and races from all over the world the eye movement patterns during various cognitive tasks are believed to be classified in the following ways (with respect to the person himself) :
Eyes Up and Left: Visual Remembered - i.e., remembered imagery (Vr).
Eyes Up and Right: Visual Constructed - i.e., constructed imagery and visual fantasy (Vc).
Eyes Lateral Left: Auditory Remembered - i.e., remembered sounds, words, and "tape loops" (Ar) and tonal discrimination.
Eyes Lateral Right: Auditory Constructed - i.e., constructed sounds and words (Ac).
Eyes Down and Left: Internal dialogue, or inner self-talk (Ad).
Eyes Down and Right: Feelings, both tactile and visceral (K).
Eyes Straight Ahead, but Defocused or Dilated: Quick access of almost any sensory information; but usually visual.
So upward eye movements means thinking, so whilea delivering a presentation looking upwards means remembering or constructing words or imagery. Whereas looking down means feeling and can indicate submission, respect, internal dialogue etc.
Studying eye gaze can help to understand if the person is interested or not. For e.g. direct eye contact while a conversation shows attention, while prolonged eye contact can feel threatening and frequent breaking of eye contact may indicate that the distraction , uncomforted, or trying to conceal real feelings. Blinking too much might indicate distress or uncomforted, whereas infrequent blinking might indicate that a person is intentionally trying to control his/her eye movements. Similarly pupil dilation can also be studied to understand a person’s emotions.