TABLE 1.

Characterization of periods in sessions with regular phase-locking (SEM ≤ 0.75*π radians) of infra-slow LFP oscillations in prefrontal cortex (Pfc) and hippocampus (Hip) to task events.

	Pfc Rtn	Pfc Rwd	Pfc VC	Hip Rtn	Hip Rwd	Hip VC
<1 cycle (n)	4	16	10	13	14	9
1–1.49 cycles (n)	6	20	6	3	28	8
1.5–1.99 cycles (n)	1	6	2	2	7	3
2–2.49 cycles (n)		4			1
2.5–3 cycles (n)					1
Mean cycle period (s)	2.48	2.22	2.05	2.62	2.45	2.32
Mean frequency (Hz)	0.40	0.45	0.49	0.38	0.41	0.43

In the six cases of two or more cycles, only data from the first cycle were counted for mean cycle period and frequency. Cycles are only counted in the period from the previous trial event to the next one, even though successive cycles could extend before or after (cf., Figure 4 and Supplementary Figure 1).