Word-based perception: a handicap in second language acquisition?

A group of proficient speakers of a second language were tested in their ability to identify individual words excised from spoken discourse. Subjects were tested in both their native language and their second language, and it was found that on average they were more proficient in their second language than their first. It would appear that the acquisition of a second language involves a more word-based approach than that of the first language, and that despite, or even because of, this word-level proficiency, overall comprehension is less good in the second language.