Skilled adult readers have typically “mapped” between 30,000 and 60,000 words into their sight word vocabulary. When we see one of those words, we recognize it instantly and unconsciously. This is what enables us to be efficient readers, able to focus on the meaning of what we read instead of just sounding out one word at a time.
When we store words in our long-term memory as sight vocabulary words, we no longer have to decode them. Because some high-frequency words (such as the, and, is, was, for, and are) are essential to learning how to read, kindergarten and first-grade teachers typically help students automatically read many of these words. Students learn to read them as whole words at the same time that they are learning how to decode most other words. However, once students are able to orthographically map, they will start to store high-frequency words as sight words on their own.
While some orthographic mapping can begin earlier, most children start to develop this skill in second and third grade. As we continue to read into adulthood, we use orthographic mapping to keep growing our sight-word vocabularies.
What Is the Mental Process of Orthographic Mapping?
Orthographic mapping is a mental process used to store and remember words. Every word has three forms – its sounds (phonemes), its orthography (spelling), and its meaning. Orthographic mapping is the process that all successful readers use to become fluent readers.
With orthographic mapping of a word, the letters we see with our eyes and the sounds we hear in that word get processed together as a sight word and are stored together in the brain. This is not the same as just memorizing the way a word looks. As Dr. David Kilpatrick, a psychologist and reading researcher, explains, orthographic mapping is not a skill, teaching technique, or activity you can do with students. Phonemic awareness and phonics skills are explicitly taught, and they then enable orthographic mapping.
With orthographic mapping, students connect something new with something they already know. Through listening and speaking, young students already know a word’s pronunciation and meaning, which are stored in their long-term memory. Students turn a written word into a sight word by matching the phonemes in the word’s pronunciation to the letter sequence they see in the word. The pronunciation of the word corresponds with its phonemes, which is why having strong phonemic awareness skills is important. The word’s letter sequence can become familiar (i.e., become a sight word) when the student attaches it to the already known pronunciation.