Summary: For decades, researchers believed the human language network was primarily located in the brain’s neocortex, the outer layer responsible for high-level cognition. However, neuroscientists have now identified a “satellite” component of this network hidden within the cerebellum—a region typically associated with motor coordination.
By analyzing brain scans from over 800 people, the team pinpointed four specific cerebellar areas that activate during language tasks. While three of these regions also engage in non-linguistic processing, one specific area in the right posterior cerebellum appears to be exclusively dedicated to language, acting as a functional echo of the neocortical language system.
This discovery could redefine our understanding of how we learn languages and offer new targets for treating aphasia and other language impairments.
Key Facts
- The “Satellite” Region: A spot in the right posterior cerebellum has been identified as a dedicated “satellite” that mirrors the activity of the core language network in the neocortex.
- Beyond Movement: While the cerebellum is famous for coordinating physical motion, this research proves it plays a sophisticated, specialized role in processing spoken and written language.
- Integrative Hub: Unlike the neocortex, which has areas strictly for language, most of the identified cerebellar regions also activate during non-language tasks, suggesting the cerebellum may help integrate different types of information.
- New Therapy Target: This cerebellar region could become a prime target for non-invasive brain stimulation to help patients recover language functions lost to stroke or brain injury (aphasia).
Source: MIT
The ability to use language to communicate is one of things that makes us human. At MIT’s McGovern Institute for Brain Research, scientists led by Evelina Fedorenko have defined an entire network of areas within the brain dedicated to this ability, which work together when we speak, listen, read, write, or sign.
Much of the language network lies within the brain’s neocortex, where many of our most sophisticated cognitive functions are carried out. Now, Fedorenko’s lab, which is part of MIT’s Department of Brain and Cognitive Sciences, has identified language-processing regions within the cerebellum, extending the language network to a part of the brain better known for helping to coordinate the body’s movements.
Their findings are reported Jan. 21 in the journal Neuron.
“It’s like there’s this region in the cerebellum that we’ve been forgetting about for a long time,” says Colton Casto, a graduate student at Harvard and MIT who works in Fedorenko’s lab. “If you’re a language researcher, you should be paying attention to the cerebellum.”
Imaging the language network
There have been hints that the cerebellum makes important contributions to language. Some functional imaging studies detected activity in this area during language use, and people who suffer damage to the cerebellum sometimes experience language impairments. But no one had been able to pin down exactly which parts of the cerebellum were involved, or tease out their roles in language processing.
To get some answers, Fedorenko’s lab took a systematic approach, using methods they have used to map the language network in the neocortex. For 15 years, the lab has captured functional brain imaging data as volunteers carried out various tasks inside an MRI scanner.
By monitoring brain activity as people engaged in different kinds of language tasks, like reading sentences or listening to spoken words, as well as non-linguistic tasks, like listening to noise or memorizing spatial patterns, the team has been able identify parts of the brain that are exclusively dedicated to language processing.
Their work shows that everyone’s language network uses the same neocortical regions. The precise anatomical location of these regions varies, however, so to study the language network in any individual, Fedorenko and her team must map that person’s network inside an MRI scanner using their language-localizer tasks.
Satellite language network
While the Fedorenko lab has largely focused on how the neocortex contributes to language processing, their brain scans also capture activity in the cerebellum. So Casto revisited those scans, analyzing cerebellar activity from more than 800 people to look for regions involved in language processing.
Fedorenko points out that teasing out the individual anatomy of the language network turned out to particularly vital in the cerebellum, where neurons are densely packed and areas with different functional specializations sit very close to one another.
Ultimately, Casto was able to identify four cerebellar areas that consistently got involved during language use.
Three of these regions were clearly involved in language use, but also reliably became engaged during certain kinds of non-linguistic tasks. Casto says this was a surprise, because all the core language areas in the neocortex are dedicated exclusively to language processing.
The researchers speculate that the cerebellum may be integrating information from different parts of the cortex — a function that could be important for many cognitive tasks.
“We’ve found that language is distinct from many, many other things — but at some point, complex cognition requires everything to work together,” Fedorenko says. “How do these different kinds of information get connected? Maybe parts of the cerebellum serve that function.”
The researchers also found a spot in the right posterior cerebellum with activity patterns that more closely echoed those of the language network in the neocortex. This region stayed silent during non-linguistic tasks, but became active during language use.
For all of the linguistic activities that Casto analyzed, this region exhibited patterns of activity that were very similar to what the lab has seen in neocortical components of the language network.
“Its contribution to language seems pretty similar,” Casto says. The team describes this area as a “cerebellar satellite” of the language network.
Still, the researchers think it’s unlikely that neurons in the cerebellum, which are organized very differently than those in the neocortex, replicate the precise function of other parts of the language network. Fedorenko’s team plans to explore the function of this satellite region more deeply, investigating whether it may participate in different kinds of tasks.
The researchers are also exploring the possibility that the cerebellum is particularly important for language learning — playing an outsized role during development, or when people learn languages later in life.
Fedorenko says the discovery may also have implications for treating language impairments caused when an injury or disease damages the brain’s neocortical language network. “This area may provide a very interesting potential target to help recovery from aphasia,” Fedorenko says.
Currently, researchers are exploring the possibility that non-invasively stimulating language-associated parts of the brain might promote language recovery. “This right cerebellar region may be just the right thing to potentially stimulate to up-regulate some of that function that’s lost,” Fedorenko says.
Key Questions Answered:
A: That’s what textbooks have said for a long time! But this research shows that the cerebellum is a multi-tasker. It has “satellite” stations that plug into the brain’s most advanced systems, including the one we use to speak and understand words.
A: In a way, yes. We have the main “headquarters” in the neocortex, but this new cerebellar area acts like a specialized satellite office. It doesn’t replace the main network, but it seems to work in perfect sync with it to help us process complex communication.
A: Very likely. Because this cerebellar region is so specialized for language, scientists are looking at it as a potential “backup” or “booster.” Using non-invasive stimulation on this part of the brain might help “re-awaken” language abilities in people suffering from aphasia after a stroke.
Editorial Notes:
- This article was edited by a Neuroscience News editor.
- Journal paper reviewed in full.
- Additional context added by our staff.
About this language and neuroscience research news
Author: Jennifer Michalowski
Source: MIT
Contact: Jennifer Michalowski – MIT
Image: The image is credited to Neuroscience News
Original Research: Open access.
“The cerebellar components of the human language network” by Colton Casto, Moshe Poliak, Greta Tuckute, Hannah Small, Patrick Sherlock, Agata Wolna, Benjamin Lipkin, Anila M. D’Mello, and Evelina Fedorenko. Neuron
DOI:10.1016/j.neuron.2025.12.030
Abstract
The cerebellar components of the human language network
Despite ample evidence of cerebellar contributions to cognition, including language, its precise role remains debated.
We systematically characterize cerebellar language-responsive regions using precision fMRI. We identify four cerebellar regions that respond to language across modalities (experiments 1a and 1b, n = 754).
One region—spanning Crus I/II/lobule VIIb—is selective for language relative to diverse non-linguistic tasks (experiments 2a–2f, n = 732), and the rest exhibit mixed selectivity.
Similar to the neocortical language system, the language-selective region is engaged during comprehension and production (experiments 3a and 3b, n = 100), shows sensitivity to linguistic difficulty (experiment 3c, n = 5), and responds to both social and nonsocial sentences (experiment 3d, n = 10).
Finally, all four regions, but especially Crus I/II/VIIb, are functionally connected to the neocortical language system (experiment 4, n = 85).
We propose that these cerebellar regions constitute components of the extended language network, with one region closely mirroring the neocortical network and the rest plausibly integrating information from diverse neocortical regions.
