Auditory segregation: stream or streams?

When auditory material segregates into "streams," is the unattended stream actually organized as an entity? An affirmative answer is suggested by the observation that the organizational structure of the unattended material interacts with the structure of material to which the subject is trying to attend. Specificially, a to-be-rejected stream can, because of its structure, capture from a to-be-judged stream elements that would otherwiise be acceptable members of the to-be-judged stream.