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How many people continue reading after college?
PsyPost reports that the number of people who read for fun appears to be steadily dropping. Fifty percent of UK adults say they don’t read regularly (up from 42% in 2015). almost one in four young people aged 16-24 say they’ve never been readers, according to research by The Reading Agency.
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 actually have?
According to Neuroimage, the structure of two regions in the left hemisphere, which are crucial for language, were different in people who were good at reading.
One was the anterior part of the temporal lobe. The left temporal pole helps associate and categorize different types of meaningful information. To assemble the meaning of a word such as leg, this brain region associates the visual, sensory, and motor information conveying how legs look, feel and move.
The other was Heschi’s gyrus, a fold of the upper temporal lobe which hosts the auditory cortex (the cortex is the outermost layer of the brain). Better reading ability was linked to a larger anterior part of the temporal lobe in the 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, to read.
What might seem less intuitive is that the auditory cortex would be related to reading. Isn’t reading mainly a visual skill? Not only. To pair letters with speech sounds, we first need to be aware of the sounds of language. This phonological awareness is a well-established precursor to children’s reading development.
The thinner left of Heschi’s gyrus has previously been related to dyslexia, which involves severe reading difficulties. The research shows that this variation in cortical thickness does not draw a simple dividing line between people with or without dyslexia. Instead, it spans the larger population, in which a thicker auditory cortex correlates with more adept reading.
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 fibres. It increases neural communication speed and can also insulate columns of brain cells from each other. Neural columns are believed to function as small processing units.
Their increased isolation and rapid communication in the left hemisphere can be thought to enable the fast, categorical processing necessary for language. We need to know if a speaker uses the category d or f when saying dear or tear rather than detecting the exact point where the vocal folds start vibrating.
The left auditory cortex may be thicker in good readers. However, it is thinner (but much more extended) than the corresponding right cortex.
Complex abilities that require integrating information tend to benefit from a thicker cortex. The anterior temporal lobe with its complex way of integrating information is indeed the thickest structure of all cortical areas.
Phonology is a highly complex skill, where different sound and motor features are integrated into speech sounds. It appears to correlate with a thicker cortex in an area near the left Heschi’s gyrus.
Bone structure can reveal a lot about reading skills. But the brain changes when we learn a new skill or practice an already acquired one.
Reading is likely to change the structure of the left Heschi’s gyrus and temporal pole. If you want to keep your Heschi’s thick and thriving, pick up a book and start reading.
If reading is less prioritized, our capacity to interpret our world and understand the minds of others will diminish.
Reading is a service to humanity!
XXX This article was first republished The Conversation.
