p551fig15.21 The most important cells types and circuitry of the cerebellum: Purkinje cells (PC) receive excitatory inputs from the climbing fibres (CF) that originate in the inferior olive (IO) and from parallel fibres (PF), which are the axons for granule cells (GC).  GCs, in turn, receive inputs from the mossy fibres (MF) coming from the precerebellar nuclei (PCN).  The PF also inhibit PC via basket cells (BC), thereby helping to select the most highly activated PC.  The PC generate inhibitory outputs from the cerebellum cortex to the deep cerebellar nuclei (DCN), as in Figure 15.20.  Excitatory signals are denoted by (+) and inhibitory signals by (-).  Other notations: GL- granular layer; GoC- golgi cells; ML- molecular layer; PCL- Purkinje cell layer; SC- stellate cell; WM- white matter.<BR>||