Cordani et al. (IMAGE) Goethe University Frankfurt Caption a) The variance in resting activity decreases significantly during twilight in the brain areas shown. The variance describes the change in brain activity during measurement. (1) visual, (2-4) somatosensory and (5) auditory cerebral cortex. b) The variance in resting activity -- shown here in the visual cortex by way of example - is reduced at 8:00 and 20:00 in comparison to other times of the day. c) Parallel to a reduction in the variance in resting activity, weak visual stimuli are more easily detected during twilight under the same light conditions. The test persons miss less visual stimuli at 8:00 and 20:00. Credit GU Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.