How Much Knowledge Is Too Little? When a Lack of Knowledge Becomes a Barrier to Comprehension

Previous research has shown that students who lack sufficient reading skills, including decoding and vocabulary, fare poorly relative to their peers. However, this study suggests that a knowledge threshold may also be an essential component of reading comprehension. A sample of students took a background-knowledge test before working on a reading-comprehension test on the topic of ecology. Results revealed a knowledge threshold: Below the threshold, the relationship between comprehension and knowledge was weak, but above the threshold, a strong and positive relation emerged. Further analyses indicated that certain topically relevant words (e.g., ecosystem, habitat) were more important to know than others when predicting the threshold, and these keywords could be identified using natural-language-processing techniques. The findings underscore the importance of having reached a basic knowledge level to be able to read and comprehend texts across different subjects: