Cranial Modifications (IMAGE) University of Chicago Press Journals Caption These are cranial modification categories used in this study: tabular erect (a), erect (b), oblique (c), slight (d), and unmodified (e). Credit Matthew C. Velasco 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.