Article:

Researchers at MIT have discovered that sentences with unusual grammar or unexpected meaning activate the brain's language processing centers more than straightforward or nonsensical sentences. The study, conducted by utilizing an artificial language network and functional MRI, shed light on how the brain processes language and its implications for higher-level cognition.

The study, led by MIT neuroscientists, focused on the brain's language processing regions, including Broca's area and other parts of the left frontal and temporal lobes. By compiling a set of 1,000 sentences from various sources, the researchers sought to identify what kinds of sentences would stimulate the language network.

Through functional MRI scans, the researchers measured the brain's language network activity while participants read the sentences. They also used a large language model similar to ChatGPT to measure the artificial language network's activation patterns in response to the same sentences. By training an encoding model, the researchers were able to predict how the human language network would respond to new sentences based on the artificial language network's response to the initial set of sentences.

The researchers identified sentences that drove maximal activity in the brain's language network, known as the "drive" sentences, as well as sentences that elicited minimal activity, called the "suppress" sentences. These sentences were then validated in a new group of participants, confirming the predicted brain responses.

Analyses of the sentences based on linguistic properties, such as grammaticality, plausibility, emotional valence, and surprisal, revealed interesting findings. Sentences that were more surprising or had higher linguistic complexity generated stronger responses in the brain's language processing centers. However, sentences that were overly simple or made no sense at all evoked minimal activation.

Lead researcher Evelina Fedorenko explained, "We found that the sentences that elicit the highest brain response have a weird grammatical thing and/or a weird meaning. There's something slightly unusual about these sentences."

The findings of this study offer valuable insights into how the brain processes language and may have broader implications for cognitive research. Understanding the factors that drive or suppress brain activity in language processing can contribute to the development of more effective language learning and comprehension strategies.

The researchers plan to extend their findings by studying speakers of languages other than English and exploring language processing regions in the brain's right hemisphere. The research was made possible through funding from various organizations, including an Amazon Fellowship, an International Doctoral Fellowship from the American Association of University Women, and support from the MIT-IBM Watson AI Lab, the National Institutes of Health, and the McGovern Institute, among others.

This groundbreaking study opens new avenues for understanding the intricacies of language processing in the human brain and could pave the way for future advancements in cognitive research and language-related therapies.