Method of detecting concentration on cellular phone call from facial expression change by image processing

Something to think about and conversation with someone distract drivers from their car driving. Decentralization of attention by a cellular phone call tends to decrease safety in driving. This paper presents an experimental result of the relation between the concentration on the cellular phone call and the facial expression change such as eye movements and blinks. Moreover, this paper describes a method of detecting the depth of the concentration from the facial expression change.