Noting that while it is difficult to estimate the absolute volume of the brain , the proportions of its various regions should the same in the endocast as it was in the large brain Larsson 's study compared the ratio of the cerebrum , which is highly demarcated , to the rest of the endocast 's volume .
While it is difficult to estimate the absolute volume of the brain , the proportions of its various regions of the brain should be the same in the endocast as it was in the live brain .