A typo interrupts the brain’s fast reading route
Reading usually feels effortless because the mind does not inspect every letter one by one. It uses familiar spelling patterns and the sentence’s context to recognize words quickly. A typo weakens those clues: an extra letter, a missing one, or a swapped pair may not match the word the reader expects.
The eyes may keep moving, but recognition is less certain. The reader may pause, look back, or test possible meanings against the rest of the sentence. That repair takes attention that would otherwise be available for following the message.
Why the delay can reach the next response
Understanding a sentence is not always finished the instant its last word appears. Readers often keep its meaning in working memory—the short-term mental space used to hold information while acting on it. If a typo leaves a word unclear, the reader may have to keep the sentence active while deciding what it says.
That matters when the next move depends on the wording: answering a question, following an instruction, or choosing between options. Instead of responding immediately, the reader first resolves the uncertainty, then uses the recovered meaning to decide what to do. A typo that does not change the message can still add a small pause; one that creates several plausible readings can demand more effort. The delay is not in the fingers pressing a key or making a move, but in the extra step of getting the message clear enough to act on.
