Grim, P. F., & White, S. H. (1965). Effects of stimulus change upon the GSR and reaction time. Journal of Experimental Psychology, 69(3), 276-281.
http://dx.doi.org/10.1037/h0021739
60 Ss were given 16 RT trials using a colored light as stimulus and then, without warning, lights differing in color but not in intensity were presented. Augmented GSR reactions occurred as a monotonic function of amount of change. Lengthened RTs were also observed; the amount of such lengthening did not appear to be simply related either to evoked GSR or to amount of stimulus change. (PsycINFO Database Record (c) 2016 APA, all rights reserved)