Objective  To investigate the changes of characteristic parameters in the eyeblink responses during the acquisition of delay and trace eyeblink conditioning in albino guinea pigs. Methods  A 500 ms tone conditioned stimulus (CS) was paired with a 100 ms corneal oxygen-puff unconditioned stimulus (US). Totally 12 guinea pigs were trained for 10 consecutive sessions of delay (

n

=6) and trace eyeblink conditioning (

n

=6).  During the experiments

a spring-return potentiometer was used to detect the activity of orbicularis oculi muscle. Homemade software written under the Matlab environment was used to quantitatively analyze the behavioral data. 

Results  Both groups of guinea pigs successfully acquired the delay and trace conditioned eyeblink responses (CRs)

respectively. Relative to the trace-conditioned guinea pigs

the delay-conditioned guinea pigs acquired the CRs with faster rates and higher peak amplitudes (

P

<

0.01). However

the CR peak latency

the peak amplitude and latency of the unconditioned eyeblink responses did not significantly change during 10 eyeblink conditioning sessions (

P

>0.05).  Conclusion  During eyeblink conditioning

the guinea pigs exhibit characteristic parameter changes of eyeblink responses similar to those observed in other common-used rodents.