His team found that people who scored highly on a questionnaire rating distractability had larger than
average volumes of
grey matter in a brain region called the left superior parietal lobe, or SPL (Journal of Neuroscience, DOI: 10.1523 / jneurosci.5864 - 10.2011).
On
average, males had larger absolute
volumes than females in the intracranial space (12 %; > 14,000 brains), total brain (11 %; 2,523 brains), cerebrum (10 %; 1,851 brains),
grey matter (9 %; 7,934 brains), white
matter (13 %; 7,515 brains), regions filled with cerebrospinal fluid (11.5 %; 4,484 brains), and cerebellum (9 %; 1,842 brains).