Selective reinforcement of HFBs in a pathway-specific manner. A, Time courses of the HFB frequencies of two simultaneously recorded neurons during the conditioning of one neuron (n = 5 pairs). Error bars indicate the SEMs of five pairs. B, Mean changes in the HFB frequencies during the period between 15 and 20 min after the onset of conditioning. *p = 0.042; ns, p > 0.05 versus preconditioning baseline of each group, paired t test; #p = 0.015, Student's t test.