Is forgetting what you have learned ever helpful? A study appearing in the January, 2007 issue of Psychological Science says that when it comes to learning a second language, at least in the beginning, the answer is yes.

While learning a new language, our native language words may distract us and inhibit our ability to express thoughts in a new tongue. In the study, University of Oregon psychologist Benjamin Levy and his colleague Dr. Michael Anderson asked native English speakers who had completed at least one year of Spanish to repeatedly name objects in Spanish. The more the students were asked to repeat the Spanish words, the more difficulty they had in producing the corresponding English words for the objects. The more a person immerses in a second language the more the brain inhibits native language - a phenomenon known as first-language attrition - making it possible to forget words one has used all one’s life.

Researchers found that the more fluent bilingual students were less prone to first-language attrition suggesting that the phenomenon assists the brain in the first stages of second language learning but becomes less necessary as the student achieves fluency.

Although the value of suppressing previously learned knowledge to learn new concepts may appear counterintuitive, Levy explains that “first-language attrition provides a striking example of how it can be adaptive to (at least temporarily) forget things one has learned.”

Association for Psychological Science