A true book lover can be recognized by the anatomy of their brain: reading is capable of shaping two regions of the left hemisphere, related respectively to understanding meanings and sounds.
This is demonstrated by a study published in the journal Neuroimage by Mikael Roll, a phonetics professor at Lund University in Sweden.
By examining MRI scans of over a thousand individuals aged 22 to 35, Roll discovered that reading habits are reflected in certain anatomical traits of the brain.
Reading particularly affects two regions of the left hemisphere.
The first is the anterior part of the temporal lobe, which helps associate and categorize different types of meaningful information. For example, to understand the meaning of a word like 'leg', this region of the brain associates visual, sensory, and motor information that communicates the appearance, feeling, and movement of legs.
The other affected region is Heschl's gyrus, a convolution of the superior temporal lobe that houses the auditory cortex: better reading ability is associated with a larger anterior part of the left temporal lobe compared to the right.
This is because reading is not just a visual task: to associate letters with sounds of the language, one must first be aware of the sounds of the language.
This phonological awareness is a well-known precursor to reading development in children: in fact, a thinner left Heschl's gyrus has been associated with dyslexia, which leads to difficulties in reading.