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The number of people who read for fun seems to be steadily declining. Fifty per cent of UK adults say they do not read regularly (up from 42 per cent in 2015) and almost one in four 16-24 year olds say they have never been a reader, according to Reading Agency investigation.
But what are the implications? Will people’s preference for video over text affect our brains or our evolution as a species? What kind of brain structure do good readers really have? My new studypublished in NeuroImage, this is how he discovered it.
I analyzed open source data from over 1,000 participants to find that readers of different abilities had different traits in brain anatomy.
The structure of two regions of the left hemisphere, which are crucial for language, was different in people who could read.
One was the anterior part of the temporal lobe. The left temporal pole helps associate and categorize different types of meaningful information. To gather the meaning of a word like legThis region of the brain associates visual, sensory and motor information convey how your legs look, feel and move.
The other was Heschl’s gyrus, a fold in the superior temporal lobe that houses the auditory cortex (the cortex is the outermost layer of the brain). Better reading ability was related to a larger anterior part of the temporal lobe in the left hemisphere compared to the right. It makes sense that having a larger brain area dedicated to meaning makes it easier to understand words and therefore read.
What might seem less intuitive is that the auditory cortex would be related to reading. Isn’t reading primarily a visual skill? Not only. To match letters with speech sounds, we must first be aware of the sounds of the language. This phonological awareness it’s a well established precursor to children’s reading development.
A thinner left Heschl’s gyrus has previously been linked to dyslexia, which involves serious reading difficulties. My research shows that this variation in cortical thickness does not draw a simple dividing line between people with and without dyslexia. Instead, it covers a broader population, in which a thicker auditory cortex correlates with more skilled reading.
Why size matters
Is thicker always better? As for the cortical structure, no, not necessarily. We know that the auditory cortex has more myelin in the left hemisphere of most people. Myelin is a fatty substance that acts as an insulator for nerve fibers. It increases the speed of neuronal communication and can also isolate columns of brain cells from each other. neural columns they are believed to work as small processing units.
It can be thought that their greater isolation and rapid communication in the left hemisphere allow for the rapid and categorical processing necessary for language. We need to know if a speaker uses the category. d either t when saying My dear either tear instead of detecting the exact point where the vocal cords begin to vibrate.