Music isn't just for entertainment. Having it on in the background can help you focus better, even if you struggle with attention deficit hyperactivity disorder.

But with music and people being so diverse, how do you decide which is best for you? Researchers have found that when it comes to boosting brainpower, there is no one-fits-all genre.

It entirely depends on the individual and what they respond to. I have many favorites — hip-hop, rap, pop, country, folk, classical, opera. So it's not about genre for me.

As a musician and Harvard neuroscientist, I've found that "familiar music," or songs that you enjoy and know best, are the most effective for maximizing concentration.

Fine-tuning my playlist for optimal focus

A 2018 study found that familiar music activates many of the brain regions responsible for movement, so the focus is "full-bodied."

This means that I can sing along and feel a learned rhythm in my body. Because I've heard the song before, I have the pleasure of anticipating what's next.

When I need to focus, familiar music helps me both relieve stress and connect with the emotions I need in order to be fully present.

For example:

• If I'm angry about something and need to let loose, I might listen to "Lose Yourself" by Eminem.
• If I've been suppressing sadness about a loss and have no energy left to focus, I'll listen to "Adagio in G Minor" by Albinoni.
• If I'm feeling angry or agitated, I might rock out to Nirvana's "Smells Like Teen Spirit."
• If I'm stressed, I might go for something that calms me, like Miley Cyrus' "Flowers" or Jason Aldean's "Big Green Tractor."

One thing I pay attention to is whether I'm "over" the music. Several studies have shown that your listening pleasure follows a U-shaped curve. First it increases, but after a while, once your brain gets used to it, the returns are diminishing.

Another group of researchers found that the type of music that most positively influences learning is "soft-fast," songs like Jason Mraz's "I'm Yours" or "Love on Top" by Beyoncé.

"Loud-fast," "soft-slow" and "loud-slow" music tended to hinder learning. Instrumental music can also be less disruptive than music with lyrics.

How familiar music affects your brain

There are many ways that music can impact the brain's ability to focus. One mechanism involves decreasing stress and cortisol, which allows the brain's attention center to operate without interruption.

In the brain, the focus centers are directly connected to the regions that process emotion, so any music that makes you more emotionally volatile could disrupt your concentration.

On the flip side, when you suppress your feelings, negative emotions just linger in your brain. And try as you might, you'll lose the capacity to focus. So, if music helps you to connect with your emotions, it can help you think more clearly, too.

Srini Pillay, M.D., is a Harvard psychiatrist and brain researcher, chief medical officer and co-founder of Reulay, CEO of NeuroBusiness Group, and the author of "Tinker Dabble Doodle Try: Unlock the Power of the Unfocused Mind." Follow him on Twitter @srinipillay and on Instagram @drsrinipillay.

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