Why do people hear their names being called in the woods?

You're walking through the woods with no one else around when you hear it: Faintly, from the background hum of the forest — impossibly, hair-raisingly — comes the sound of someone calling your name.

Could it be a ghost? Bigfoot? Some elaborate practical joke by a prank TV show? It's likely none of those — so why do people sometimes hear their names or other words being called when no one is actually saying anything? And is it ever something to worry about?

The phenomenon of hearing intelligible voices or noises in meaningless background noise is known as "auditory pareidolia." The sources of this noise vary; they may include electric fans; running water; airplane engines; the hums of washing machines; or white-noise machines, according to audiologists. It is an auditory sub-type of pareidolia, in which people see faces or other meaningful patterns in ambiguous images.

Auditory pareidolia isn't considered a type of auditory hallucination, which occurs when a person hears sounds that don't exist in reality and transpire appear without any external stimulus, such as white noise. Such hallucinations are common in various mental conditions, including schizophrenia, post-traumatic stress disorder and bipolar disorder. Non-psychiatric hallucinations have also been reported by those with hearing loss, although the condition, known as musical ear syndrome, is relatively rare and understudied. 

But people with and without these conditions can experience auditory pareidolia, which emerges specifically from background noise.

Related: Why do people feel like they're being watched, even when no one is there?

But why does auditory pareidolia happen in the first place?

"Think of your brain as having this big database of patterns. All the words that you know, and you've ever heard in your life are in there," Neil Bauman, an audiologist and CEO of the Center for Hearing Loss Help based in Washington, told Live Science. "It chooses what it thinks is the best pattern. That best pattern may not be right at all. In fact, it could be way out."

The sounds a person hears when experiencing auditory pareidolia aren't completely invented by our brains. Rather, they stem from a misperception of real sounds — for example, an unexpected peak in a static signal or in the background noise coming from a forest.

"The patterns in most noise sources change all the time," Andrew King, director of the Centre for Integrative Neuroscience at the University of Oxford, told Live Science. "Take white noise: Averaged over time, it becomes flat, but there will be certain points where the pattern is slightly different. That may be enough to trigger a person to recognize something." 

King attributes auditory pareidolia to our brain's constant attempts to make sense of and find patterns in the world around us. It can be especially likely to occur when somewhat recognizable noises are masked by the background hum of a noisy environment, such as a restaurant or a bar. 

In these cases, the brain utilizes a process called contrast gain control, adjusting the sensitivity of brain cells that respond to auditory and visual data so they can adapt to the constant input.

"A highly evolved capacity to maximize the likelihood of being able to hear communication or other sounds may be very important," King said. In other words, humans may be wired to listen for snippets of language in a din of background noise, even if they’re not necessarily there. 

Despite being commonly reported, auditory pareidolia is not as well studied by neuroscientists as its visual counterpart. That's in part because the triggers that can make people mishear certain sounds are not as consistent or predictable as those that may make them falsely recognize faces, such as the man in the moon.

"To what extent this is a "bottom-up" process — driven by the statistics of the stimuli — as opposed to a "top-down," attention-based mechanism is pretty unclear," King said. Bottom-up processing relies on the brain piecing together bits of stimuli to make sense of them, while top-down processing is more driven by our expectations and prior knowledge. 

"You will be more likely, probably, to pick out something that's familiar to you, but that's purely speculation," King said. He thinks it's "probably a top-down process."

So, if you ever hear your name called from the dark depths of an abandoned forest, you might not need to turn and flee in the other direction. But if you are concerned you’re hearing voices where no sound exists, it may be worth getting professional help.

This article is for informational purposes only and is not meant to offer medical advice.