Here's what's going on in your brain when you can't spell a word
In a study published this week in the journal Brain, researchers at Johns Hopkins University studied people who had suffered brain damage from strokes or tumors and now have problems spelling words.
What they found is that the problems were linked to damage in three brain areas involved in either remembering words or recalling letters one-at-a-time.
The findings also offer some clues to what goes on in a the brain of healthy spellers, the researchers say.
"To be a good speller, there are many different cognitive processes that need to be working smoothly together," Brenda Rapp, a cognitive scientist at Johns Hopkins who led the study, told Business Insider.
First of all, you need to store the spellings of words, a system involving longterm memory. Then, you have to be able to hold onto a word in your mind as you recall each letter, which involves something called working memory.
Previous research suggested these two processes existed, but Rapp and her colleagues wanted to know whether they were separate processes, or whether they were really part of the same process.
To find out, they scanned the brains of 33 people who had suffered a stroke or other injury that affected one or both of these two memory systems. All of the patients had been good spellers before, but had lost that ability after their brains became damaged.
The types of spelling errors the patients made had to do with what type of brain damage they had, the researchers found. Those with damage to working memory - who misspelled words like "lion" as "liot" or "lino" - had brain damage in their parietal lobe, a region that processes information from different senses.
Meanwhile, those with longterm memory damage - who misspelled words like "yacht" as "yat" or "sauce" as "soss" - had damage in one of two brain areas: the ventral temporal area or the inferior frontal gyrus. The researchers think one of these areas may be where the word memories are stored, and the other area may be the machinery used to go into that storage and retrieve those memories.
Interestingly, the patients in the study did not have other memory problems in general, like problems recalling faces or objects, Rapp said. The deficits seemed to be very specific.
But what about people who are just poor spellers in general? Rapp studies them too, and she's found that these people don't necessarily have brain damage. Instead, they probably had trouble developing these spelling areas as a child.
By comparison, in people who are extremely good spellers, these brain areas may be more highly developed than in other people, Rapp said.
We still don't know whether spelling ability is based on genetics or learning. Of course, written language hasn't existed for long enough to have shaped the human genome, but some brain areas have been co-opted for this purpose, and these could be influenced by genes.