Study: Fast Talkers Convey the Same Amount of Information as Slow Talkers

A study analyzes the relationship between how fast people speak and how much information they actually relate.

Do you take your time when you speak, thinking out each word to make sure it’s the most appropriate in that situation? Or do you speak two hundred words a minute, blanketing listeners with your ideas? Either way, you would probably get across the same amount of information in the same amount of time. That’s the conclusion of a new study from Brown University. 


Uriel Cohen Priva, the author of the study and assistant professor in Brown's Department of Cognitive, Linguistic and Psychological Sciences, found that when people speak there is an interplay between how quickly they speak and how complicated is their speech. It turns out there's a narrow channel of communication data - people who speak fast tend to use simpler words and easier sentence construction, while those who speak slower use more complicated, “contextually unexpected” words and word combinations. But in both cases you get the same info.

“It seems the constraints on how much information per second we should transmit are fairly strict, or stricter than we thought they were,” said Cohen Priva

Why there are some “constraints” is not yet clear. It could be either because the listener can process only so much information at a time or the opposite - the speaker’s inability to come up with and express more than a certain amount of information.

Priva’s conclusions were based on analysis of two independents sets of data - Switchboard Corpus, which includes 2,400 annotated phone conversations, and the Buckeye Corpus, containing 40 long interviews. Altogether the data had the speech of 398 people. 

The researcher calculated and compared the frequencies of words, usage of the less frequent passive versus active voice, taking into account each speaker’s age and gender and other factors. He also studied how long each word would take to be spoken on average versus how long each particular speaker needed.  

Information theory considers the less predictable and more surprising message as more information. To help explain how different statements convey information, the study suggests considering the phrase “dog bites man”. This expression actually provides less information than the phrase “man bites dog” with is a less expected situation. So while having the same words, the two expressions provide a very different amount of information. And if you want to up the ante, saying “human bites dog” is even more lexically informative, because the word “human” is used less frequently than “man”.

The finding that faster speakers limit their information is explained by the study as an adjustment necessary for maintaining the speed of speech. 

“Repeatedly choosing more frequent words and structures would mean that speakers would rarely have to slow down for infrequent words and structures, thereby maintaining overall faster speech rate,” says the study. 

What’s also notable is that the researcher found the same basic relationship between information rate and the speed of speech across all the data.

“We could assume that there are widely different capacities of information per second that people use in speech and that each of them is possible and you can observe each and every one,” said Cohen Priva. “But had that been the case, then finding these effects would have been very difficult to do. Instead, it’s reliably found in two corpora in two different domains.” 

One clue as to why there might be a limitation on the information rate lies in the difference between how men and women speak. While both men and women conform to the overall speech pattern the researcher found, men tend to convey more information than women given the same speech rate. According to Cohen Priva, this may be because women are more likely to want to make sure their listener is actually understanding what they are saying. This hypothesis corresponds to other studies that show women more likely to provide verbal cues during dialogue that ensure understanding. 

Interestingly, as the study notes, “slow speech rate was correlated with high usage of passive voice constructions.”

Positive correlation between slow speech rate, measured in mean pointwise speech rate and normalized, and passive voice usage, measured in log odds in Switchboard. Each point represents a speaker in a conversation. The lines represent the raw correlations between speech rate and passive voice usage, by gender.  Source - U. Cohen Priva / Cognition 160 (2017) 27–34. 

The study “Not so fast: Fast speech correlates with lower lexical and structural information” will be published in the March issue of Cognition. You can read it online here.

Cover photo: CIRCA 1950s: Couple in heated argument. (Photo by George Marks/Retrofile/Getty Images)

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In truth, so much of what happens to us in life is random – we are pawns at the mercy of Lady Luck. To take ownership of our experiences and exert a feeling of control over our future, we tell stories about ourselves that weave meaning and continuity into our personal identity.

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Yale scientists restore brain function to 32 clinically dead pigs

Researchers hope the technology will further our understanding of the brain, but lawmakers may not be ready for the ethical challenges.

Still from John Stephenson's 1999 rendition of Animal Farm.
Surprising Science
  • Researchers at the Yale School of Medicine successfully restored some functions to pig brains that had been dead for hours.
  • They hope the technology will advance our understanding of the brain, potentially developing new treatments for debilitating diseases and disorders.
  • The research raises many ethical questions and puts to the test our current understanding of death.

The image of an undead brain coming back to live again is the stuff of science fiction. Not just any science fiction, specifically B-grade sci fi. What instantly springs to mind is the black-and-white horrors of films like Fiend Without a Face. Bad acting. Plastic monstrosities. Visible strings. And a spinal cord that, for some reason, is also a tentacle?

But like any good science fiction, it's only a matter of time before some manner of it seeps into our reality. This week's Nature published the findings of researchers who managed to restore function to pigs' brains that were clinically dead. At least, what we once thought of as dead.

What's dead may never die, it seems

The researchers did not hail from House Greyjoy — "What is dead may never die" — but came largely from the Yale School of Medicine. They connected 32 pig brains to a system called BrainEx. BrainEx is an artificial perfusion system — that is, a system that takes over the functions normally regulated by the organ. The pigs had been killed four hours earlier at a U.S. Department of Agriculture slaughterhouse; their brains completely removed from the skulls.

BrainEx pumped an experiment solution into the brain that essentially mimic blood flow. It brought oxygen and nutrients to the tissues, giving brain cells the resources to begin many normal functions. The cells began consuming and metabolizing sugars. The brains' immune systems kicked in. Neuron samples could carry an electrical signal. Some brain cells even responded to drugs.

The researchers have managed to keep some brains alive for up to 36 hours, and currently do not know if BrainEx can have sustained the brains longer. "It is conceivable we are just preventing the inevitable, and the brain won't be able to recover," said Nenad Sestan, Yale neuroscientist and the lead researcher.

As a control, other brains received either a fake solution or no solution at all. None revived brain activity and deteriorated as normal.

The researchers hope the technology can enhance our ability to study the brain and its cellular functions. One of the main avenues of such studies would be brain disorders and diseases. This could point the way to developing new of treatments for the likes of brain injuries, Alzheimer's, Huntington's, and neurodegenerative conditions.

"This is an extraordinary and very promising breakthrough for neuroscience. It immediately offers a much better model for studying the human brain, which is extraordinarily important, given the vast amount of human suffering from diseases of the mind [and] brain," Nita Farahany, the bioethicists at the Duke University School of Law who wrote the study's commentary, told National Geographic.

An ethical gray matter

Before anyone gets an Island of Dr. Moreau vibe, it's worth noting that the brains did not approach neural activity anywhere near consciousness.

The BrainEx solution contained chemicals that prevented neurons from firing. To be extra cautious, the researchers also monitored the brains for any such activity and were prepared to administer an anesthetic should they have seen signs of consciousness.

Even so, the research signals a massive debate to come regarding medical ethics and our definition of death.

Most countries define death, clinically speaking, as the irreversible loss of brain or circulatory function. This definition was already at odds with some folk- and value-centric understandings, but where do we go if it becomes possible to reverse clinical death with artificial perfusion?

"This is wild," Jonathan Moreno, a bioethicist at the University of Pennsylvania, told the New York Times. "If ever there was an issue that merited big public deliberation on the ethics of science and medicine, this is one."

One possible consequence involves organ donations. Some European countries require emergency responders to use a process that preserves organs when they cannot resuscitate a person. They continue to pump blood throughout the body, but use a "thoracic aortic occlusion balloon" to prevent that blood from reaching the brain.

The system is already controversial because it raises concerns about what caused the patient's death. But what happens when brain death becomes readily reversible? Stuart Younger, a bioethicist at Case Western Reserve University, told Nature that if BrainEx were to become widely available, it could shrink the pool of eligible donors.

"There's a potential conflict here between the interests of potential donors — who might not even be donors — and people who are waiting for organs," he said.

It will be a while before such experiments go anywhere near human subjects. A more immediate ethical question relates to how such experiments harm animal subjects.

Ethical review boards evaluate research protocols and can reject any that causes undue pain, suffering, or distress. Since dead animals feel no pain, suffer no trauma, they are typically approved as subjects. But how do such boards make a judgement regarding the suffering of a "cellularly active" brain? The distress of a partially alive brain?

The dilemma is unprecedented.

Setting new boundaries

Another science fiction story that comes to mind when discussing this story is, of course, Frankenstein. As Farahany told National Geographic: "It is definitely has [sic] a good science-fiction element to it, and it is restoring cellular function where we previously thought impossible. But to have Frankenstein, you need some degree of consciousness, some 'there' there. [The researchers] did not recover any form of consciousness in this study, and it is still unclear if we ever could. But we are one step closer to that possibility."

She's right. The researchers undertook their research for the betterment of humanity, and we may one day reap some unimaginable medical benefits from it. The ethical questions, however, remain as unsettling as the stories they remind us of.

Ashes of cat named Pikachu to be launched into space

A space memorial company plans to launch the ashes of "Pikachu," a well-loved Tabby, into space.

GoFundMe/Steve Munt
Culture & Religion
  • Steve Munt, Pikachu's owner, created a GoFundMe page to raise money for the mission.
  • If all goes according to plan, Pikachu will be the second cat to enter space, the first being a French feline named Felicette.
  • It might seem frivolous, but the cat-lovers commenting on Munt's GoFundMe page would likely disagree.
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