They say that the left side of the brain controls the right.

They say that the right side has to work hard all night.

It is with these two lines of lyric that Paul Simon kicks off his 1983 song “Think Too Much (a)”. Three questions occurred to me after first hearing Simon sing those lines, questions that ultimately went beyond the scope of Simon’s song and into the territory of a well known theory about the human brain.

And so, because of these two lines of lyric, I began a process of thought, research, and experimentation that culminated with all three questions being tackled in this article. So what do “they” mean, who exactly is “they”, and are “they” correct in their affirmations?

What do “they” mean?

In other words, what are “they” talking about? Well, “they” are talking about the Left Brain – Right Brain dominance theory. The Indiana Wesleyan University’s Center for Learning and Innovation wrote the following to describe the left brain-right brain dominance theory:

The left brain vs. right brain theory suggests that people have a dominant brain hemisphere, and that the dominant hemisphere influences one’s learning and personality. Specifically, left brain dominant people are more logical and right brain dominant people are more creative.

In essence, this theory claims that every human being has one side of the brain that’s more dominant than the other, either the left side or the right side.

Furthermore, it claims that if someone’s a “left-brain person” (meaning his or her left side of the brain is more “developed”), then he or she is more likely to think logically and mechanically, but if someone’s a “right-brain person” (meaning his or her right side of the brain is more “developed”), then he or she is more likely to think more creatively and freely.

Both sides of the brain are, to some extent, mutually exclusive under this theory, as it is often implied that “left-brained” people do not tend to fair well in “right-brain” tasks and vice versa.

Interesting.

But who spreads this theory around and who came up with it?

Who exactly is “they”?

“They”, as in the people who stand by and spread the left brain-right brain dominance theory, is a difficult concept to define.

Most of my family members, most of my professors, and some of my friends (I didn’t want to expose them by name in this article so I stuck with non-specifics, but they’re out there!), all stand by and spread the Left Brain – Right Brain dominance theory.

So it’s nearly impossible to narrow “they” down to a single category of people, considering that the theory seems to be well widespread by now.

But who is “they” as in whoever came up with the theory? “They” represents a combination of the media and a Nobel Laureate neuropsychologist, Roger Sperry.

In the 1960’s, Roger Sperry conducted the split-brain experiments, a set of brain experiments that would years later earn him the 1981 Nobel Prize in Physiology or Medicine.

Without delving too deeply into Sperry’s work (see here for more on Sperry’s experiments), the split-brain experiments basically demonstrated that when split, the left and right hemispheres of the brain specialize in different tasks.

However, the media wasn’t satisfied.

After being released to the public, Sperry’s findings were over-interpreted and played up by the media to the point where “when split, the left and right hemispheres of the brain specialize in different tasks” became:

“We Are Left-Brained or Right-Brained; Two Astonishingly Different Persons Inhabit Our Heads.”

Quite a difference between the two right? That last quote is actually the title of a 1973 article published by The New York Times. In the end, it was the media’s flashy, sexy take on the brain research of a Nobel Laureate that gave birth to the now popular Left Brain – Right Brain dominance theory.

So, is this theory even valid?

Are “they” correct in their affirmations?

This was the $1,500 question (I don’t need much).

Are “they” correct in their affirmations? Is the Left Brain-Right Brain dominance theory valid or isn’t it? Personally, I’ve always had my doubts about this theory. Categorizing people (and tasks) as either “left-brained” or “right-brained” feels to me like categorizing people as either purely good or purely evil; it’s just a bit too easy, a bit too convenient; it doesn’t account for all the gray areas.

So I decided to actively question it by conducting an experiment.

In the video below, I recorded myself playing the guitar. More specifically, I recorded myself playing a piece of music I love (the Coda from the classic song “Layla”) with the help of a loop pedal.

With this loop pedal, I was able to add one layer of music at a time until I had a complete backing arrangement, over which I then composed an original guitar solo.

Surely, this would qualify as a “right-brain” task. Or would it? First, here’s the video:

Under the Left Brain-Right Brain dominance theory, this would surely be considered a “right-brain” task, given that music is often categorized as a purely creative endeavor.

Sure, coming up with the arrangement and the solo was a creative task (to a certain extent). It was not until I was done recording the video that the real experiment began.

I decided to analyze all the work that I had put in to create this video to see if it in fact was a pure “right-brain” task.

It wasn’t.

After careful analysis, I found that the “right-brain” sub-tasks that went into the making of the video were as dependent on themselves as they were dependent on the “left-brain” sub-tasks that went into the making of the video, and vice versa.

In other words, in order to complete the task at hand, in this case, a video recording of my interpretation of “Layla (Coda)”, the “right brain” needed the “left brain”, and the “left brain” needed the “right brain”.

So, what were some of those “left-brain” subtasks that were vital to the making of this seemingly pure “right-brain” task?

Before recording the video, I had no idea how to record a guitar performance for YouTube. I had to mechanically read and learn about things like which type of microphone to use, how to position it against the amp, and how to sync the mic with my webcam.

In order for me to be as creative as I could be with a loop pedal, I had to first become familiar with how it worked, from how to plug it in, to how to operate it while playing. I accomplished this by googling “Ditto Looper tips and tricks”, and of course, reading through its user manual, which hardly qualifies as artistic work.

Before sitting down to create my arrangement and my original solo, I drew a chord chart outlining the chords that are present in the piece with the duration of each chord.

I also jotted down the notes that make up each chord, and some scales that I could use to improvise over each chord. I am absolutely certain that without this chord chart and without the technical knowledge of music theory that’s behind it, both my arrangement and my original solo would have been completely different from what they are. And I’m pretty happy with what they are.

So while the left brain-right brain dominance theory is, as Paul Simon would agree, undoubtedly interesting, I do not think it is valid.

But nobody should take my word for it. All anyone has to do is try and find a task, any task, in which only “one side of the brain” is at work. I do not think it is possible.

That person will most likely succeed in proving that there’s more to the brain than either left or right.

There cannot be poetry without structure. There cannot be physics without imagination. There cannot be one without the other.

Like the left hand and the right hand of a guitar player, logic and creativity feed off one another in order to achieve the task at hand.