- Changes in bit-mapped contingent negative variation (CNV) activity due to initial normal involutional processes of the human brain. Zappoli, R., Versari, A., Paganini, M., Arnetoli, G., Gangemi, P.F., Muscas, G.C., Arneodo, M.G., Battaglia, A. International journal of psychophysiology : official journal of the International Organization of Psychophysiology. (1992)