Sasha Matson

My wife saw me putting on my new LP of Joni Mitchell's great For the Roses album and said: "Oh, our breakup album!" Never mind the confusing details—we're obviously still (or again) together—that's how intense the bonds are for many people with Joni's music: We people of a certain age set the clock of our lives by her recordings.

When I need information about recordings, I go to Discogs. At Discogs, Kevin Gray has more than 2500 entries. That's as good an indicator as any of the amount of ground he has covered in his career so far as a creative participant in the recorded-music art known as mastering. Since starting out in the early 1970s, in Los Angeles, he has worked for all the major music labels and many independents, in all music genres.

It says something about the power of music that some individuals fading into dementia can still recognize the music they knew earlier in their lives. Not to denigrate new music, or music one hasn't heard before, but our mental jukeboxes award top chart numbers to music that we have lived with over time. Those DJs making their playlists in our brain are the toughest of critics. They don't care what anyone else might think, "Close to You" is staying in the rotation. Music and memory are linked.