Figure 8.

Changes of odor responses after learning manipulated by postsynaptic facilitation. A, After learning of odor A via manipulation of postsynaptic facilitation in both LN-PN and LN-LN, the trajectories of mixture odor responses moved toward the unlearned odor, odor B, in PCA space. B, Corresponding to A, after learning of odor A, the correlation coefficient between odor A and mixture odors reduced. On the other hand, the correlation coefficient between odor B and mixture odors increased. C, After learning of odor A manipulated by postsynaptic facilitation in LN-LN synapses only, the mixture odors stayed at middle between odor A and odor B in PCA space. D, Corresponding to C, the changes of correlation coefficient among odor responses are small. E, When postsynaptic facilitation was set up at LN-PN synapses only, the trajectories of mixture odors were found to move toward the unlearned odor, odor B. F, Corresponding to E, the correlation coefficients between odor A and mixture odors reduced. At the same time, the correlation coefficients between odor B and mixture odors increased.