Synchronicity of spontaneous medial dorsal thalamic unit activity and HCSs in the ACC. A, Spontaneous MD multiunit activity (tops) and ACC CSD oscillations (bottom, yellow) were recorded with multichannel probes simultaneously. Signals of multiunit activity in the MD were selected (channels 9–16), and the total multiunit number of selected channels was averaged (blue line trace, arrow) over time. The average was transferred to a waveform trace (arrowhead). B, Simultaneous MD multiunit activity and ACC CSD oscillations with morphine treatment (Bi) or noxious stimulation (Bii). Ci, Relationship between ACC CSD amplitude and number of MD multiunit activity: control (black), morphine treatment (blue), and noxious stimulation (red). Cii, Comparison of the ratio of the CSD and multiunit activity in the control, morphine treatment, and noxious stimulation groups. #p < 0.05, compared with control group (paired t test).