Cooling of the cerebellar interpositus nucleus abolishes somatosensory cortical learning-related activity in eyeblink conditioned rabbits.
Nictitating membrane movement and multiple-unit activity in the somatosensory cortex were recorded from rabbits during paired (N=6) and unpaired (N=5) presentations of a tone conditioned stimulus (CS) and an airpuff unconditioned stimulus (US). A behavioural conditioned response (CR) to the CS and an accompanying neural response in the somatosensory cortex developed only in the paired group. Inactivation of the cerebellar interpositus nucleus abolished both the acquired CR and the accompanying neural response. However, the CS facilitated both behavioural and neural responses to the US during the inactivation. Thus, the absence of the CR could not be accounted for by the general inability of the CS to alter the behaviour constituting the CR or the activity of the somatosensory cortex. These findings suggest that the efferent copy of the signal related to the eyeblink CR is projected from the cerebellum to the cerebral cortical areas of the US modality.
Department of Pyschology, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland. wikgren@psyka.jyu.fi
Jan
J
Wikgren
David G
DG
Lavond
Timo
T
Ruusuvirta
Tapani
T
Korhonen
D000818:Animals; D001245:Association Learning / Q000502:physiology; D001931:Brain Mapping; D002529:Cerebellar Nuclei / Q000502:physiology*; D003215:Conditioning, Eyelid / Q000502:physiology*; D004569:Electroencephalography; D019054:Evoked Potentials, Motor / Q000502:physiology; D005073:Evoked Potentials, Somatosensory / Q000502:physiology; D005260:Female; D007036:Hypothermia, Induced; D009415:Nerve Net / Q000502:physiology; D009433:Neural Inhibition / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000502:physiology; D011817:Rabbits; D012815:Signal Processing, Computer-Assisted; D013003:Somatosensory Cortex / Q000502:physiology*