Period 1 CRISPR (IMAGE) Penn State Caption New research shows that the circadian clock gene, Period 1, also plays a role in memory formation in the dorsal hippocampus—a memory-related region of the brain—helping mice to form better long-term memories during the day. Left panel shows fluorescent staining of the dorsal hippocampus in blue, with a virus expressing the CRISPR gene editing tool in green, expanded in the right panel to show expression within hippocampal cells. Reducing the expression of Per1 with CRISPR resulted in reduced memory performance during the day. Credit Kwapis Lab, Penn State Usage Restrictions Credit must be given to the creator. Only noncommercial uses of the work are permitted. No derivatives or adaptations of the work are permitted. License CC BY-NC-ND 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.