Can We Ever Stop Thinking?

That Susan is so funny...oh, I need to bring the car to the wash tomorrow…did I turn off the stove...why is this person being so loud...my toe feels weird...I feel like I know that person...here comes the sun, doo-doo-doo-doo.

We often find ourselves in an endless thought loop. And every so often, we try to stop this endless flow of thoughts by telling ourselves to just stop thinking. But do we or can we ever really stop thinking? 

It depends on how you define "thinking," said Michael Halassa, an assistant professor in the department of brain and cognitive sciences at MIT. A thought, which is the result of chemical firing between brain cells, can happen both on the conscious and unconscious level, he said.

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The type of thinking we are aware of, such as the endless thoughts that pop up when we're trying to sleep, can, in theory, be silenced. That's presumably what meditation is all about, Halassa said. 

But even though that's what meditators strive to do — it's not clear how much of a blank state they can actually achieve. "I don't know if [completely stopping thinking] is theoretically possible and if it is, I think that would be incredibly difficult to test," said Julia Kam, a cognitive scientist at the Knight Lab at the University of California, Berkeley. 

But it's clear that "meditators are a lot more tuned into what their thoughts are," Kam told Live Science. "So when they're supposed to be focused on something and their mind shifts away, then they're just a lot better at picking up on that shifting of attention."

There's a difference between having a thought, and being aware that you're having a thought, she said. So if you ask someone what they're thinking about and they respond with "nothing," they could just not be aware that they're having thoughts, Kam said. For instance, you could be deeply in thought about a relationship or an upcoming test, and you only become aware of it when someone taps you on the shoulder and snaps you out of it, she said. People who are thinking about "nothing" could also be having stream of consciousness thoughts that don't tell a coherent story, Halassa said.

But the brain never actually stops "thinking" in a broader sense. Most thoughts are actually happening in the background without us being aware of them, and "there's not really a way to turn these things off," Halassa told Live Science. 

If you see a familiar face in a crowd and think you know them, you might not be able to come up with how you know them right away, Halassa said. But maybe hours later, you'll suddenly remember. That's a result of your brain "thinking," in the background, he said.

Even making decisions happens mostly unconsciously. For example, some of this background "thinking" results in what we call a "gut feeling," Halassa said. "A lot of times our brains are crunching a lot of numbers and spitting out a gut feeling that we ultimately go with." We don't always have conscious access to our brain's decision-making process and sometimes we create a story to explain the decision — sometimes it's accurate, sometimes it's not, he added.

Kam agrees that how you define "thinking," changes the answer to the question. "If you mean thinking, as in having an inner dialogue with ourselves, then, yes, we can stop having that inner dialogue," Kam said. But if thinking means not focusing attention on anything in particular, "I think that would be a lot more difficult for the layperson." 

Even sitting here reading this, thinking about thinking is sending messages across a chain of neurons in the brain. So if we somehow manage to stop ourselves from "thinking" consciously, or achieve a "blank state of mind" through meditation, the brain won't sign off. It will continue to have thoughts — we just won't be aware of them.

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Originally published on Live Science.