Figure 1.

Locomotor activity in Egfr^wa2/wa2 mice during 12 h:12 h light:dark cycles and three-hour light pulses given during the dark cycle. Horizontal white and black bars represent light and dark exposure, respectively. Vertical axis indicates wheel-running activity. (A) The majority of Egfr^wa2/wa2 mice tested were indistinguishable from wildtype controls in behavior, though two Egfr^wa2/wa2 mice did exhibit a phase shift resulting in abnormally high daytime activity, as well as abnormally high activity during a three hour light pulse. (B) Abnormal wheel running activity during three-hour light pulses followed a characteristic one-hour of activity suppression in three Egfr^wa2/wa2 mice (red), while wildtype (dark blue) and the majority of Egfr^wa2/wa2 mice (light blue) demonstrated suppression of activity throughout the pulse. Grey areas, lights off; white area, light pulse.