Cognitive processing impairments in a supra-second temporal discrimination task in rats with cerebellar lesion.

Delphine Callu (1) , Nicole El Massioui (1) , Gérard Dutrieux (1) , Bruce L. Brown (2) , Valérie Doyère (1)

1 NAMC - Neurobiologie de l'apprentissage, de la mémoire et de la communication
2 QC - Queens College [CUNY]

The role of interpositus nuclei (IN) in timing in the sub-second range is well supported in eyeblink conditioning studies. Timing impairments shown in the seconds range in patients with intermediate cerebellar lesion, and known intermediate cerebellar cortex projection to IN raise the question of a possible involvement of IN in timing in the supra-second range as well. To address this question, we tested rats (Sprague-Dawley) given bilateral lesions of IN with Colchicine in a 2- vs. 8-s temporal discrimination task, followed by three daily sessions of a temporal bisection tests with five added intermediate non-reinforced durations. IN lesioned rats showed normal acquisition of the temporal discrimination, but a transient impairment of temporal sensitivity during the bisection tests. In addition, their response latencies suggested a different behavioral strategy from that of control animals. Our results indicate that the IN of the cerebellum may not be critically involved in temporal processing in the 2-8 s range, but may play a role in the cognitive processes that access temporal information in the mediation of choice behavior.

Domaines: Neurobiologie; Psychologie et comportements; Sciences cognitives

Delphine Callu, Nicole El Massioui, Gérard Dutrieux, Bruce L. Brown, Valérie Doyère. Cognitive processing impairments in a supra-second temporal discrimination task in rats with cerebellar lesion.. Neurobiology of Learning and Memory, 2009, 91 (3), pp.250-9. ⟨10.1016/j.nlm.2008.12.002⟩. ⟨hal-01467462⟩