Figure 3. Eyeblink Conditioning and Locomotion Conditioning Are Not Impaired.

(A) Eyeblink conditioning increased the percentage of conditioned responses (CRs) significantly (all p < 0.05; habituation session versus acquisition session 6) in PICK1 KO, GluR2Δ7 KI, and GluR2K882A KI mutants, as well as their littermate controls. (B) Kinetics of unconditioned responses (URs) are unaffected in all groups. Latency to UR onset, R1 during unconditioned stimulus (US)-only trials, and R1 peak amplitude versus UR peak velocity (right) also did not differ between PICK1 KO, GluR2Δ7 KI, GluR2K882A KI, and control mice. Each dot represents the mean value of one animal. (C) Amplitude (left three panels) and timing (right two panels) of CRs are normal in all three mutant mice compared to that of control mice. Left two panels: Means of all eyeblink CR raw data traces for each group in paired trials during training sessions 2 and 6. Middle panel: Averaged CR amplitude for sessions 2 and 6. Right two panels: Mean percentage of CR peak times (25 ms bin) for each group during training session 2 and 6. At the end of the training (session 6), in all groups the majority of CR peak times are clustered around US onset at 850 ms. Short-latency responses (SLRs), which occur frequently during mouse eyeblink conditioning, are indicated. CS onset is set at 500 ms, US onset at 850 ms, interstimulus interval (ISI) = 350 ms, US duration = 30 ms. (D) Analysis of locomotion conditioning on the Erasmus Ladder revealed no significant differences in number of missteps and steptime between mutant and control mice. Both motor performance values (left panels without background) and motor learning values (right panels with gray transparent background) were not affected. During locomotion conditioning, the US, i.e. a rising rung, occurs 250 ms after the onset of the CS (a 15 kHz tone). All mutants show an acquired change in steptime after (post) the CS compared to before (pre). This change is not different from that seen in littermate controls (Table S2). For number of mice per group, see Table S1. The p values for individual mutants versus all controls and versus littermates are listed in Table S2. Error bars denote SEM.