Figure 4: Circadian rhythm data. Normalised data for amplitude values were calculated as post-MFB surgery values as a percentage of mean prelesion (BLN, baseline) data for the circadian parameters of: LA (a), cBT (b), and HR (c), for sham-operated controls and 6-OHDA lesioned rats. Data was taken from the day after MFB surgery (day 2) until 12–14 days after surgery. Data was analysed from day 4, when recovery of HR and body temperature reached levels comparable with the baseline in the lesioned rats. There was no significant change in LA (a) or cBT (b) between groups. However, there was a lower diurnal rhythm of HR for 6-OHDA lesion rats than sham-operated controls (ANOVA: , ; post hoc group difference ). Circles represent controls; boxes represent 6-OHDA lesioned rats. BT, body temperature, HR, heart rate, LA, locomotor activity.