A study reveals how the Arabic language affects the building of communication networks in the brains of native speakers

A study reveals how the Arabic language affects the building of communication networks in the brains of native speakers

The connections between the different brain regions responsible for language processing depend on the language an individual was brought up with.

A new MRI-assisted study reveals that the native language we speak forms the communication in our brains that may underlie the way we think, meaning that a person's native language may shape how the brain builds connections between the various axes of information processing.

The differences observed in the structures of these language networks were related to linguistic characteristics in the study participants' native languages: German and Arabic.

"So the difference we found there should not be because of the different ethnic background but really because of the language we speak," said Alfred Anwander, a researcher at the Max Planck Institute for Human Cognitive and Brain Sciences in Germany who led the study published in the journal NeuroImage .

Although the language network grows into one of the strongest networks in the brain, at birth the connections are weak.

Anwander explained that as we learn to speak, connections strengthen between different brain regions responsible for different types of language processing, such as recognizing words from sounds and interpreting the meaning of sentences.

Different languages ​​may "tax" some types of language processing more than others. The researchers wanted to see how these differences affect the formation of connections in the brain.

Previous studies have shed light on the areas of the brain that are active during language processing. These regions are mainly located in the left hemisphere of the brain, although both sides of the brain are involved in auditory processing, and the area that evaluates stress and intonation in pronouncing words is located in the right hemisphere.

Patrick Friedrich, a researcher at the Institute of Neuroscience and Medicine at the Jülich Research Center in Germany, who was not involved in the study, noted that the brain language network is understood to be "somewhat universal between participants of different indigenous languages." However, the scientists noted differences. How the brain processes second languages.

"I thought this study was really interesting because it shows for the first time a structural difference depending on the original experience, rather than languages ​​learned later," Friedrich explained.

The study included 94 participants, half of whom spoke only German, and the other half spoke only Arabic, who had recently settled in Germany. 

Although they spoke different languages ​​and grew up in different cultures, the participants were closely matched in terms of factors that can influence brain wiring, such as age and level of education.

Brain scans were obtained using a magnetic resonance imaging (MRI) machine.

The high-resolution images not only show the anatomy of the brain, but also allow communication between brain regions to be tracked using a technique called "diffusion-weighted imaging". The data showed that the focal white matter connections of the language network adapt to the processing demands and difficulties of the native language.

The scans revealed that German speakers showed increased connectivity in the left hemisphere regions involved in language processing, compared to Arabic speakers.

And Anwander explained that the German language is grammatically complex, which means that the meaning of a sentence is extracted less from word order than from the grammatical forms of words.

He said the syntactic processing regions are located mostly in the frontal parts of the left hemisphere, so the higher connectivity within the left hemisphere makes sense.

On the other hand, Anwander described the Arabic language as linguistically complex, and while sentence order remains more stable, the meanings of words can be more difficult to decipher.

The researchers noted increased connectivity between the left and right hemispheres of the Arabic speakers.

In a more precise sense, the brains of Arabic speakers work in a more complex way than German speakers, given that the Arabic language requires more listening and concentration between the speaker and the listener, and therefore, the degree of brain processing requires a faster effort to understand the Arabic language spoken by Arabic speakers. 

The team concluded that native Arabic speakers showed a stronger connection between the left and right hemispheres of the brain than German speakers.

Anwander explained that it is possible that the language network formed by a person's native language may influence other non-linguistic cognitive abilities. For example, a German speaker's memory may be affected by the need to hear complete sentences before analyzing their meaning.

David Green, emeritus professor of psychology at University College London, expressed reservations about the study's findings, saying that in addition to the linguistic features of language, cultural features of conversation, such as how people use gestures, may also shape brain networks.

The study also did not cover all brain regions involved in language processing, nor did it include measures of brain activity that could be compared between individuals.

"We need to understand the diverse ways in which the brain can solve a given task and the nature of this diversity across individuals," Green emphasized.

This is one of the first studies to document differences between the brains of people who grew up with different indigenous languages ​​and could give researchers a way to understand cross-cultural processing differences in the brain.

In a future study, the research team will analyze structural changes in the brains of Arabic-speaking adults as they learn German over a six-month period.

The discovery of 30,000 new viruses hidden in the DNA of microbes!

A team of researchers has made a startling discovery while analyzing the genomes of single-celled microbes: thousands of previously unknown viruses are "hidden" within their DNA.

The researchers found the DNA of more than 30,000 viruses integrated into the various genomes of single-celled microbes, they report in a new study. They explain that viral DNA may enable a host cell to replicate fully functional viruses.

“We were very surprised by the number of viruses we found with this analysis,” says lead author Christopher Pellas, an ecologist who studies viruses at the University of Innsbruck in Austria. “In some cases, it turns out that up to 10% of the microbe’s DNA is made up of hidden viruses.” .

These viruses do not appear to infect their hosts, the researchers say, and may be beneficial. Some of the new viruses are similar to phages, a type of virus that infects other pathogenic viruses that try to infect their host cell.

"It is not yet clear why there are so many viruses in the genomes of microbes," Bellas says. "Our strongest hypothesis is that they protect the cell from infection by dangerous viruses."

Living on Earth means encountering viruses, the most abundant biological entities on the planet, which collectively infect every form of life. They are very diverse, and use many different tactics to exploit the cellular host.

Whatever the semantic debates about whether viruses are alive, they certainly insert themselves into the lives of other organisms. Some even reproduce by adding their DNA to a host cell and becoming part of its genome.

When this occurs in a germ cell, it can lead to internal viral elements (EVEs), or viral DNA that is passed from one generation to the next in a host species.

The scientists found the drug virus infection in a wide variety of organisms, including animals, plants and fungi. Mammals carry a variety of viral fragments in their DNA, for example, and about 8% of the human genome consists of DNA from ancient viral infections.

The study authors explain that most of these are no longer functional and are considered "gene fossils". Research suggests that endogenous viral components may be adaptive in humans and other organisms, although they may help ward off modern viruses.

The researchers point out that this is true of many single-celled eukaryotes, noting that these microbes are commonly infected and killed by giant viruses.

And if the phages are already living in a host cell, they can reprogram a giant virus to build phages instead of replicating themselves, potentially saving the host.

According to the new study, the DNA of the newly discovered viruses is similar to the DNA of phages, indicating that microbes may have some protection against giant viruses thanks to the "integrated" viruses present in their genomes.

The study of EVEs to date has focused mainly on animals and plants, the researchers write, with little interest in protists — that is, eukaryotic organisms that are not animals, plants, or fungi — even though they represent the majority of eukaryotic biodiversity on Earth.

Discovering thousands of new viruses hidden in the DNA of microbes was not the original goal of Bellas and his colleagues, who planned to study a new group of viruses that they found in the waters of Gusenkolssee, a mountain lake in the Austrian state of Tyrol.

"Initially, we wanted to find the origin of 'Bolinton-like viruses' with our study. However, we didn't know which organisms would normally be infected with these viruses. That's why we conducted a large-scale study to test all microbes whose DNA sequence is known," Bellas says. with it.”

To do this, they enlisted the help of Leo, a high-performance computing group at the University of Innsbruck that can efficiently analyze huge amounts of data.

Noting genes from phages and other viruses in several microbial genomes, the researchers decided to investigate further, using Leo to systematically analyze all publicly available draft genome sets of protists.

They found that the autologous viral elements are "hidden in difficult-to-assemble repetitive regions of single-celled eukaryotic genomes," they wrote, noting that thousands of integrated viruses in some species indicate that viruses make up a previously unidentified large group of proto-genomes.

The study also found evidence that many endogenous viral elements are not just genetic fossils, but functional viruses, the researchers write, "suggesting that diverse arrays of these elements may be part of a host antiviral system."

The study has been published in the Proceedings of the National Academy of Sciences.