Oscillations (image) Norwegian University of Science and Technology Caption This shows 20-40 Hz oscillations when well-trained rats were sampling odor cues (arrow). In lateral entorhinal cortex (LEC, top), which relays signals from olfactory sensory areas to the hippocampus, strong oscillatory activities were observed in the 20-40 Hz band, as well as 6-10 Hz (theta) oscillations. Medial entorhinal cortex (MEC, bottom), in which grid cells reside, showed only theta oscillations. Credit NTNU Usage Restrictions None 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.