From bickering with strangers online to politically charged holidays with relatives, many discussions today wind up at loggerheads.
But Dartmouth researchers have found a conversational recipe they call "pink noise" that may help people get back to more enjoyable and engaging interactions, according to a new study in Science Advances.
Pink noise is strongest in conversation that balances the familiar and the unexpected, says Katie O'Nell , the study's first author and a doctoral candidate in psychological and brain sciences. People focus on one subject long enough to learn from each other, then switch to a new topic to keep the conversation fresh, she says.
"We find that conversations exhibiting more pink noise tend to be rated as more enjoyable," O'Nell says. "When people talk about good conversation, they often use metaphors like 'in sync' or 'being on the same wavelength' that break down when we consider them in mathematical terms. We show that over-synchronization is probably a bad thing and that moving both toward and away from each other can help conversationalists feel like they click."
"We're hoping our work opens up more research into how to improve human communication, especially around difficult topics," says Emily Finn , the study's corresponding author and an assistant professor of psychological and brain sciences.
"Our findings suggest that if you've stayed on a topic for long enough that it's feeling tedious, don't be afraid to inject some randomness and search for a new topic together," she says. "If you're bouncing between topics more quickly than you'd like, take a moment to reflect on what your partner is saying and ask follow-up questions."
The Dartmouth team used transformers—the neural-network software behind chatbots such as Claude and ChatGPT—to convert an open-source dataset of transcripts from nearly 1,700 conversations known as the CANDOR corpus into a numerical map. Each person's turn to talk is its own data point, with similar sentences living nearby each other and dissimilar snippets located farther away.
The researchers then looked at how far away each part of the conversation was from the one before it, rendering these distances as distinct signals similar to a sound wave. They tested whether each signal looked more like red, white, or pink noise.
These "colors of noise" are part of the noise spectrum, with each having different characteristics. While most people think of noise as an unwelcome interruption like radio static, a signal's noise color simply indicates the relative power of different frequency bands.
Red noise is muffled and low-frequency, like the monotone of a distant ocean, versus the sharp, high-frequency white noise of a television with no signal. Pink noise is like the steady roar of a waterfall and has a consistent sound energy.
Pink noise is evident in many systems that require flexible switching between stability and randomness to function properly, from heartbeats and the coordination of neurons to the coupling of climate systems such as the ocean and the atmosphere.
"I think of pink noise as a 'Goldilocks signal' between red and white noise," Finn says. "Pink noise exists in the middle of these two types of signals, balancing the slow, stable meandering of red noise with the quick, jumpy movements of white noise. It gives you some amount of stability, while also allowing you to make a change when you need to."
On the canvas of a conversation, white-noise dialogue rambles with no particular focus, like a conversation with a toddler, while red-noise conversation is intensely focused and unyielding, like an unfriendly legal deposition, the researchers report in Science Advances.
"We need more empirical work to test which strategies work to introduce more pink noise into conversation, but we suggest that people pay attention to when their conversations feel more red or white," Finn says.
An example of pink noise could be two people initially talking about sports who have different preferences but find common ground, O'Nell says. One speaker says, "I'm a huge baseball fan," to which the other replies, "I like basketball better myself." The first speaker then replies, "My son does too, it's faster paced," to which the other person says, "Exactly! Does your son play any sports?"
"They're adapting to each other," O'Nell says. "The second person isn't a fan of basketball but doesn't just dead-end the conversation or move to a different topic. He finds something adjacent in his enjoyment of a different sport that allows the other speaker to find her own connection. He then latches onto the topic of her son to learn more about her since it's clear they're not going to talk about sports teams at length."
The dataset of conversations the Dartmouth team used to build their numerical map also includes post-conversation surveys. The team reports that the amount of pink noise in a conversation accurately predicted how much people said they enjoyed the exchange and felt connected to the person they talked to.
The team then evaluated transcripts from a speed-dating podcast to better understand the importance of pink noise in real-world conversations. They report that first-date conversations with more pink noise were more likely to lead to a second date.
But pink noise is not just for people born with a knack for conversation, according to the study in Science Advances. An evaluation of 25 podcasts with dual hosts reveals that pink noise increased over the first 50 episodes for nearly all the pairs of speakers.
"This result is particularly interesting because it suggests that coordinating our words in a way that results in pink noise might be a learnable skill," O'Nell says. "Anyone who's suffered through an awkward conversation on a date or at the Thanksgiving table may have a reason for hope. People may be able to move towards pinker conversations with practice."
The Dartmouth study—which includes co-author Kiara Sanchez, a former assistant professor of psychological and brain sciences—is distinct from existing research on conversational dynamics because it suggests that divergence is an important part of getting the most of an exchange, O'Nell says. Most other studies focus on how speakers synchronize during conversation and become more similar to each other over time.
"By invoking this idea of pink noise, we're able to show how important it is for people to break away from each other as well," O'Nell says. "After all, speaking to a parrot would result in perfect alignment, but be a terrible conversation."
