Dittys On The Brain

Blame It On The Auditory Cortex

I spent four hours in the car last night with someone whose taste in music is different than mine. Being the kind person that I am, I relinquished control of the CD player to him. That meant four hours of a rather random array of music, some good, some bad.

His selection included Cream, Cure, Who, Ramones, Nirvana, Beatles, and a few other things mixed in. Sixties, Seventies, Eighties, Nineties (or at least very early Nineties). Nothing more recent. Fortunately, nothing from the Fifties. Personally, I don’t think anything good musically came out of that decade.

I tried to figure out a pattern from his selection of music. There probably is one, but I could not make it out. Maybe that is what a mix is – themeless and random.

The musical selection was much better than that of my usual driving partner. She likes to listen to oldies. Most oldies were crap when they first came out, and have not gotten any better with age.

I was OK with last night’s selection until this morning. I woke up with a Ramones tune stuck in my head. I don’t know why it couldn’t have been Rocky Raccoon or anything more pleasant.

Why Ramones? I never could figure out the attraction some people had for the Ramones or the entire punk genre. They might have been fun to see live, but their recordings must rank in one of the lower percentile levels.

So why is this song stuck in my head?

I heard a report on National Public Radio a few days ago which introduced me to the auditory cortex. The report called it the iPod of the Brain. You can hear the report at this site. [I am still amazed at the internet. You don’t have to read the transcripts – you can hear it as I did.] [2019 update: I could not find the earlier NPR broadcast, although it is probably on the web somewhere. Here, though, is a link to an interesting explanation of the auditory vortex.]

The auditory cortex is the part of the brain that processes, organizes, and plays back sounds. This is sort of an automatic process, beyond your conscious control.

Researchers at Dartmouth College did an interesting experiment. Subjects were played familiar and unfamiliar tunes, instrumentals and songs with lyrics. All the while hooked to scanners to measure brain activity.

Now here’s the trick. The researchers intentionally inserted blank spots in the music. When the subjects heard familiar tunes, they didn’t notice the gaps. Evidently, the auditory cortex remembered the tune and automatically filled in the gaps.

In contrast, when the subjects heard unfamiliar tunes, they did notice the blank spots. The auditory cortex couldn’t fill it in. Also, the brain was better in filling in gaps in songs with lyrics then they were in filling in gaps in instrumentals.

So this may explain why you remember familiar songs and why they are replayed from time to time in your head.

It doesn’t explain, as NPR noted, why the annoying sounds are the ones that stay in the brain.

I have a theory. I think it’s the brain’s way of reminding you not to listen to crap.

Correction posted on Wolverine Café May 16, 2005: I wish to dispel one notion mentioned in Dittys on the Brain. It was noted that our auditory cortex replays familiar songs in our brain and that, for some reason, it prefers to replay the annoying songs.

My auditory cortex has been working overtime. For the past 48 hours it has been playing one song over and over and over again. The song, though, is not so annoying. It is Me and Bobby McGee. I heard it performed live on Saturday by someone at least as good as Janis Joplin.