Are Freestyle (Improvised) Songs Protected by Copyright?

Dear Rich: Are songs that are created "on the spot" protected by copyright laws? I do freestyle songwriting and upload the video or MP3 on the internet. My songs contain original lyrics and melodies and are done without any type of preparation whatsoever. Most of my songs are without instruments, just my voice (acapella style). Your freestyle songwriting is protected by copyright law because it is “fixed” -- that is, you’ve recorded your songs as videos and MP3s. You don’t need full instrumentation to claim a songwriting copyright either; words and melody should be suitable. Your copyright enables you to chase anyone who has access to your songs and who copies them. (By the way, this is what your brain looks like while freestylin'.)