CHEMICAL, SENSESSustained human chemosignal unconsciously alters brain functionJacob, Suma1; Kinnunen, Leann H.2,3; Metz, John3; Cooper, Malcolm3; McClintock, Martha K.1,2, CA Author Information 1Institute for Mind and Biology, and 2Department of Psychology, University of Chicago, 5730 South Woodlawn Avenue, Chicago, IL 60637, USA; 3MICRO, Inc., Chicago, IL, USA CACorresponding Author Received 11 May 2001; accepted 25 May 2001 Neuroreport 12(11):p 2391-2394, August 8, 2001. Buy Abstract The human chemosignal, Δ4,16-androstadien-3-one modulates psychological state without being consciously discernible as an odor. This study demonstrates that Δ4,16-androstadien-3-one (androstadienone) alters cerebral glucose utilization both in subcortical regions and in areas of the neocortex not exclusively associated with olfaction. These widely distributed changes are consistent with modulation of an integrated neural network for regulation of emotional and attentional states. This is the first study to demonstrate the effects of a sustained chemosignal on brain metabolism and to show that they are similar to those of long acting chemical substances that affect psychological states. Moreover, this provides the first evidence that a human chemosignal has distributed effects on cortical processes and brain metabolism even when it is not detected consciously. © 2001 Lippincott Williams & Wilkins, Inc.