The pattern of complex spike activity results from a combination of factors. First, after entering the cerebellum single climbing fibers branch and connect with up to ten Purkinje cells within a sagittally oriented microzone, inducing synchrony in rostro-caudal direction (Armstrong et al. 1973a; Armstrong et al. 1973c; Armstrong et al. 1973b; Sugihara et al. 2001); second, inferior olivary neurons are densely electrotonically coupled by dendrodendritic gap junctions, further enhancing the potential for synchrony (Llinas et al. 1974; Sotelo et al. 1974; De Zeeuw et al. 1995; Lang 2002; Marshall et al. 2007); and third, due to a unique set of conductances neurons of the inferior olive show sub-threshold oscillations (STO's) in their membrane potential with frequencies ranging from 1 to 3 Hz and/ or 3 to 10Hz (Llinas & Yarom 1981; Yarom Y. & Llinás 1981; Llinas & Yarom 1986; Khosrovani et al. 2007), on the beat of which their action potentials may ride (Llinas et al. 1974; Bloedel & Ebner 1984; Mathy et al. 2009; Bazzigaluppi et al. 2012; Gruijl et al. 2012). To what extent the tendency to oscillate and to fire in synchrony interact is still under debate (Devor & Yarom 2002a; Devor & Yarom 2002b; Leznik & Llinás 2005; Placantonakis et al. 2006; Welsh 2002). For example, pharmacological blockage of gap junction coupling does not abolish olivary oscillations (Leznik & Llinás 2005; Lang 2002), but enhancing the oscillatory rhythm with harmaline can enhance the level of synchrony (Llinas & Sasaki 1989; Lang et al. 1996; Jacobson et al. 2009). Intra-olivary coupling delays have not been studied in great detail and it is not completely clear at the systems electrophysiological level to what extent gap junction coupling in the olivocerebellar system can influence the oscillatory properties and related ensemble pattern formation. So far, cross-correlation studies of complex spike activity have largely focused on the zero-time bin peaks in the anesthetized or non-moving preparation, trying to tackle the mechanisms underlying synchrony (Zeeuw et al. 1996; Lang et al. 1996; Wylie et al. 1995) or restrict themselves to non-moving periods of awake recordings (Lang et al. 1999). It it also known that different phases of movement can recruit different sub-sets of Purkinje cells, by that creating dynamic patterns of complex spike synchrony (Welsh et al. 1995).