The effect of puromycin on retention of conditioned cardiac deceleration in the goldfish

Abstract

The electrocardiogram was used to measure conditioned heart rate deceleration to a light-off signal paired with a punishing electrical shock in the goldfish. The learned response was retained for several days but was rapidly lost with extinction trials. Intracranial injections of puromycin administered just before or immediately after a training session did not appear to block formation of memory of this response. This result is discussed in relation to previous studies on the possible effects of puromycin on conditioned fear and instrumental learning.

Granule cells control recovery from classical conditioned fear responses in the zebrafish cerebellum

“…3j ), suggesting that granule cells control the recovery process. This finding is in contrast to previous reports that inhibiting activity in the cerebellum abolishes the conditioned bradycardia response in goldfish 12 , 13 , 31 and mammals 7 , 8 , 10 , and that inhibiting the IOs or the interpositus nucleus (IN, a deep cerebellar nucleus) in mammals abrogates fear conditioning 9 , 10 , which all suggest a positive role of the cerebellar neural circuits in conditioned fear responses. The discrepancy between these studies and our findings might be caused by the difference in the cell populations inhibited; the previous inhibition experiments perturbed cerebellar function non-selectively.…”