Figure 2From: 40-Hz ASSR fusion classification system for observing sleep patterns The international 10-20 system seen from (A) left and (B) above the head. A, ear lobe; C, central; Pg, nasopharyngeal; P, parietal; F, frontal; Fp, frontal polar; O, occipital. Source http://www.bem.fi/book/13/13.htm.Back to article page