Skip to main content
. Author manuscript; available in PMC: 2009 Jul 1.
Published in final edited form as: Neurobiol Learn Mem. 2008 Apr 22;90(1):200–216. doi: 10.1016/j.nlm.2008.02.009

Figure 4.

Figure 4

Differential fear conditioning to 19 kHz discontinuous and continuous tones. (A) Spectrograms of the 19 kHz discontinuous tone pips (top) and the 19 kHz continuous tone (bottom). (B) Overall mean percent freezing to the CS+ and the CS− (N = 24). (C) Mean percent freezing among subjects (n = 12) that received the 19 kHz pips (part A, top) as the CS+ and 19 kHz continuous tone (part A, bottom) as the CS−. (D) Mean percent freezing among subjects (n = 12) that received the 19 kHz continuous tone as the CS+ and 19 kHz pips as the CS−. The baseline level of freezing (before the CS onset) is plotted on the left of the vertical dashed line. Asterisks (*) denote significant differences between CS+ and CS−. Error bars represent ± 1 SE.