Philip Gough's (1972) One Second of Reading model suggests that reading is a sequential mental process and the emphasis is on the smaller speech sounds. According to Gough, the speech sounds are connected together to form individual words. The decoding is essential to the reading process. Contrary to the whole language approach which supports the meaning first, the understanding of the author's message comes last. Readers are able to grasp higher level text than they can decode. This inability prevents the reader from accessing more difficult text. The burden is relieved during read-alouds. Expert decoders are able to read higher level text.
LaBerge and Samuels (1974) developed theory of automaticity or automatic information processing which is widely accepted. The idea is based on the premise that the human mind functions like a computer and has limited capacity for multitasking. Therefore, the decoding and comprehension cannot happen simultaneously. One process will inevitably interfere with the other and diminish the process of each. An example is a novice bike rider. When a child is learning to ride a bike, he can become so consumed with balancing, holding the handle bars correctly, he may miss the more important tasks such as steering. Likewise, a beginner reader can get bogged down with decoding so much that the comprehension can't happen. When the novice rider attempts to do both at once, like a computer, he crashes and the learning is sabotaged.
Constructivist Theory is based on the premise that meaning is constructed through experience. Constructivism embraces a top-down rather than a bottom-up instructional approach. Instead of teaching all the details that will eventually lead to the main idea, students discover the main idea first in a meaningful manner and then attend to the details. Unlike the bottom-up theory, students are not restricted from getting to the author's message by decoding the text first. The students have access immediately. Each student brings something unique to the table. Her personal experiences shape the reading process and prior knowledge is the foundation for reading instruction.
The Holistic theory is based on the top-down theory. Words are not taken apart and decoded in a sounding out fashion. Students increase vocabulary through hearing read-alouds and rereading worthy literature that is not chosen so much for level of difficulty but for meaning. Mistakes or miscues are understood as a student's willingness to take risks in reading. Words are understood in the context of the whole passage. More difficult vocabulary does not dissuade a first-grader from selection of a text. The students are encouraged to guess the meaning of the word based on the whole meaning or the picture. Prior knowledge and experience drives the reader to select reading materials rather than teacher selected texts.