Skip to main content
. 2009 Feb 11;4(2):e4387. doi: 10.1371/journal.pone.0004387

Figure 9. Heart rate changes of subjects during pre-exposure to objects that were conditioned with the CS-UCS and during testing with the CS-only.

Figure 9

HR was measured during (a) the first and second conditioning session in subjects that experienced objects receiving the paired CS-UCS, and during (b) testing, which entailed 5 repeated presentations of the CS-only. HR changes in subjects from both strains were similar across the 2 conditioning sessions and therefore pooled for graphical presentation. Each data point represents a 10-s bin. HR is presented as a change (Δ) from the baseline HR of each mouse (see Table 2). (c) Conditioned freezing responses of subjects during presentation of the CS-only (N = 15 subjects/genotype; age = 7–9 wks). Asterisks represent significant (P<0.05) HR differences between BALB and B6 subjects. Numeric symbols represent significant (P<0.05) differences in freezing between BALB and B6 subjects. Behavioral data were scored in duplicate by 2 independent raters and all data are presented as the mean±s.e.m.. Inter-rater reliability, rp = 0.94, d.f. = 143.