A groundbreaking study has now discovered that the human brain can process sentence structures within as short as 125 milliseconds. The research team led by Professor Liina Pylkkänen of New York University also discovered that the brains can almost instantly identify familiar grammatical structures, thus contradicting a belief long thought to be true: namely, that people process sentences word for word.

How was this study conducted?

Scientists took 36 subjects using a non-invasive brain scanning technique to study this rapid brain activity. Demonstrated short sentences to subjects and then asked to compare them with slightly modified versions. For example, they first saw a three-word sentence for 300 milliseconds, and then something very similar appeared where one word or its order changed. The participants were then asked whether the two sentences were identical.

The researchers found that when the brain is fed grammatically standard sentences, there is a huge activational spike in the left-middle temporal cortex after just 130 milliseconds. Lists composed solely of nouns took a bit longer than 50 milliseconds to stimulate related activity in the brain.

 

Sentence structure vs. meaning

 

The interesting findings here were that even sentences with grammar mistakes or implausible constructions were identified faster than lists of words. Researchers concluded that comprehension of sentences is a faster process, as the brain knows the structure rather than trying to "understand" by meaning alone. What this implies is that sentences are processed much more like visual inputs much like seeing a familiar object quickly.

Prof. Pylkkänen explained this phenomenon by drawing the analogy between this and visual recognition. She says, "When something you perceive fits really well with what you know about in this case, grammar, this top-down knowledge can help you identify the stimulus really fast.”

While the work was done in English, the researchers believe that such similar processing dynamics can be established for other languages as well, too, despite grammatical structures. Published in Science Advances, new information came to the fore about how our brains "see" sentences; it is processed nearly as fast as images.

This discovery casts skepticism upon the theoretical understanding of how we process language in general; however, the same discovery can furnish further studies on different linguistic processes and sentence structures within the human brain.