Fig. 4From: Effects of nicotine on regional blood flow in the olfactory bulb in response to olfactory nerve stimulationSummary of nicotine effects on olfactory bulb blood flow responses induced by olfactory nerve stimulation. The stimulus frequencies were 2 (a–c), 20 (d–f), and 100 Hz (g–i). a, d, g Peak responses were measured by maximum blood flow changes within 8 s (1st peak) or later (2nd peak) after the onset of stimulation (see upper inset), and expressed as percentages of the corresponding basal values (mean value for 10 s before time zero). b, e, h Durations were measured by time (s) until the increased blood flow returned to the basal values (see upper inset). c, f, i Area under the curve (shaded gray shown in the upper inset) were measured as averaged blood flow values for a 60-s period after the onset of stimulation and expressed as percentages of the corresponding basal values (mean value for 10 s before time zero). Each column and vertical bar represent the mean ± SEM (n = 8). *p < 0.05, **p < 0.01: significantly different from the response before nicotine injection as determined using Wilcoxon’s matched-pairs signed-rank testBack to article page