Mouse Internal Clock Shifts with Light Brightness Despite Different Light Patterns

Circadian phase shifts in mice showed no significant variation when light intensity was matched, regardless of the spatial distribution of illumination.

• High-contrast and low-spatial-frequency light patterns did not change the amplitude of circadian phase shifts when total light intensity was controlled.
• Circadian responses in mice were primarily predicted by total scene irradiance rather than by the spatial arrangement of light.
• A metric based on the area of highest light intensity was less effective in predicting circadian responses than total irradiance.
• The findings suggest that the mouse circadian system effectively integrates light across different spatial patterns.

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