Today's digital media deliver rapid messages -- such as phone notifications and text overlays on videos -- to our brains at an impressive speed, far faster than spoken words reach us. But can we process these texts as quickly as we can determine the makeup of the visuals that are also a part of our screen life?
The answer appears to be "yes," according to new studies by a team of New York University linguistics and psychology researchers. It has discovered that when a brief sentence is flashed, our brains detect its basic linguistic structure extremely quickly -- in roughly 150 milliseconds, or about the speed of a blink of an eye.
"Our experiments reveal that the brain's language comprehension system may be able to perceive language similarly to visual scenes, whose essence can be grasped quickly from a single glance," says Liina Pylkkänen, a professor in NYU's Department of Linguistics and Department of Psychology, who led the research, which is reported across papers appearing in Science Advances and the Journal of Neuroscience. "This means the human brain's processing capacity for language may be much faster than what we might think -- in the amount of time it takes to hear one syllable, the brain can actually detect the structure of a short sentence."
The rise of email, followed by social media and smartphones, has shifted our reading experience from a contemplative, leisurely activity to quick and fragmented consumption of digital content, with short messages constantly flashing at us through phone notifications, online platforms, and, perhaps soon, augmented realities.
"This shift has made it clear that our brains not only have the ability to instinctively process rapid messages, but can also make snap decisions based on them -- like whether to keep or delete an email or how to respond to a brief social media update," explains Pylkkänen. "But how well do we really understand these quick messages and how do our brains manage them? The fact that our brains can, at least in some way, grasp the meaning of these fast messages from just a single glance may reveal something fundamental about the processing potential of the language system."
The scientists began their research by considering current scientific explanations of how we understand language, which center on word-by-word sentence processing models. The researchers concluded these don't effectively account for how quickly our brains can process entire sentences seen at a glance, as opposed to word by word like in speech.
In seeking a better understanding, the authors conducted a series of experiments, measuring brain activity using magnetoencephalography while participants read word lists that were either grammatical sentences (e.g., nurses clean wounds) or just lists of nouns (e.g., hearts lungs livers). The results showed that the brain's left temporal cortex -- used for language comprehension -- starts distinguishing simple three-word sentences from unstructured word lists as quickly as 130 milliseconds after seeing them.
"This speed suggests that at-a-glance sentence comprehension may resemble the rapid perception of a visual scene rather than the slower, step-by-step process we associate with spoken language," explains Pylkkänen. "In the amount of time that it takes one to hear one syllable, the brain can actually detect the structure of a three-word sentence."
The scientists add that even when a sentence contains an agreement error, with the wrong number marking on the verb (nurses cleans wounds), or lacks a plausible meaning, this rapid structure detection occurs in the left temporal cortex.
"This suggests that the signals reflect the detection of basic phrase structure, but not necessarily other aspects of the grammar or meaning," explains Jacqueline Fallon, the Science Advances study's first author, who was an NYU researcher at the time of the work and is now a doctoral student at the University of Colorado.
Related research on these rapid signals in the Journal of Neuroscience, led by NYU graduate student Nigel Flower, further supported this idea. It showed that even small errors in phrase structure -- like swapping two adjacent words, "all are cats nice" -- cause a drop in the brain's rapid response. Such small mistakes can easily go unnoticed by readers. In fact, Flower observed that starting around 400 milliseconds, the brain appears to "correct" the mistake, processing the sentence as if it were fully grammatical.
"This suggests that the brain not only quickly recognizes phrase structure but also automatically corrects small mistakes," Flower explains. "This explains why readers often miss minor errors -- their brains have already corrected them internally."
By flashing the study's participants entire sentences all at once, as opposed to word by word, the researchers could uncover the brain's ability to quickly identify basic phrase structure, even if the meaning of the sentence was nonsensical or there was a grammatical mistake that still maintained the right phrase structure.
"These findings may provide valuable insights into the brain's intrinsic language processing abilities, independent of the usual sequential flow of spoken language," says Pylkkänen.
The studies were supported by grants from the National Science Foundation (BCS- 2335767) and the NYU Abu Dhabi Institute.