Portal de Periódicos da CAPES

Questioning the role of rebound firing in the cerebellum

2008; Nature Portfolio; Volume: 11; Issue: 11 Linguagem: Inglês

10.1038/nn.2195

1546-1726

Karina Alviña, Joy T. Walter, Adam Kohn, Graham Ellis-Davies, Kamran Khodakhah,

Neural dynamics and brain function

Under some in vitro conditions, neurons of the deep cerebellar nuclei show a phenomenon called rebound potentiation, where, following a strong hyperpolarization, their membrane potential briefly rebounds to a more depolarized level causing a transient increase in firing rate. The authors, however, found that under more physiological conditions in vitro or in vivo, deep cerebellar nuclei neurons rarely showed rebound potentiation. This finding necessitates a re-evaluation of some cerebellar models, where rebound potentiation was postulated to be involved in plasticity and/or information processing. A key component of recent theories on cerebellar function is rebound firing in neurons of the deep cerebellar nuclei (DCN). Despite the robustness of this phenomenon in vitro, in vivo studies have provided little evidence for its prevalence. We found that intact mouse or rat DCN neurons rarely showed rebound firing under physiological conditions in vitro or in vivo. These observations necessitate a critical re-evaluation of recent cerebellar models.