Objective      To investigate the changes of behavioral parameters during dual-task eyeblink conditioning in aging Kunming mice.       Methods      A total of 5 15-month-old mice (aged group) and 5 3-month-old mice (young group) were assigned to receive paired training of tone (intensity of sound 70 dB) conditioned stimulus (CS) in different audio frequency (3 kHz and 1 kHz) and a 100-ms comeal oxygen-puff unconditioned stimulus (US). Behavioral parameters

including eyeblink conditioned responses (CR)

amplitude of peak (AP) and latency of peak (TP) were observed

and the results were compared between the 2 groups.       Results      After 12 days’ pairing training

CR% in trace eyeblink conditioning (TEBC) and delay eyeblink conditioning (DEBC) was increased with the elapse of training days in both aged mice group and young mice group. CR acquisition rate between the 2 groups appears significantly different from the tenth day (P0.05). There was significant difference in AP between the 2 groups from the tenth day in TEBC (P0.05)

and also on the sixth day and the twelfth day in DEBC (P0.05). Surprisingly

acquisition rate of TEBC which trained with 3-kHz-CS was obviously higher than the DEBC with 1-kHz-CS in 2 groups.       Conclusion      Aged Kunming mice can not learn dual-task eyeblink conditioning well compared with young ones

which indicating that aging affects the association learning in mice directly.