Tone/light-induced increases in ACh release (fmol/sample)
| Cortex | Hippocampus | |
|---|---|---|
| Novel stimuli | 436 ± 99* | 169 ± 59* |
| Habituation | 153 ± 114 | 85 ± 78 |
| Conditioned fear | 556 ± 185* | 212 ± 62* |
Differences in ACh release (in fmol/sample) between the average of three prestimulus baseline values and the second (i.e., peak) sample obtained during the tone/light presentation.
*Tone/light stimulation value significantly different from baseline values, p < 0.02 (paired two-tailed Student’s ttest).