Introducing the brain: how is language handled (Introduction)

by David Turell , Wednesday, September 20, 2023, 17:44 (220 days ago) @ David Turell

Still confused as experts create and debate studies:

https://www.newscientist.com/article/2393046-the-entire-brain-may-be-involved-in-langua...

"Brain regions identified as “language centres” are actually hubs that coordinate the processing of language throughout the brain, argues a controversial new study.

"We have misunderstood how the brain processes language, says a controversial new analysis. The brain regions that have been identified as specialised language processing centres are actually hubs that coordinate the processing of language across multiple brain regions, argue Jeremy I. Skipper at University College London and his colleagues.

"Their idea runs counter to most models of language in the brain and has been met with scepticism.

"Since the late 1800s, there has been growing evidence that specific brain areas process language. For example, Broca’s area in the frontal cortex is thought to be involved in speech. People with damage to this area understand what is said to them, but can struggle to speak. Brain imaging studies consistently show activity in this and other areas when performing language tasks.

"Skipper doesn’t dispute that regions like Broca’s area are involved in language processing, but he thinks much of the rest of the brain also plays a role. “There’s a ton of processes that go into language,” he says. “It’s the most complicated thing we do as human beings.”

"To demonstrate this, he and his colleagues conducted a two-part study. In the first part, they reanalysed data from existing meta-analyses of previous studies of brain imaging data. They confirmed that research looking at language processing showed activation was localised to regions like Broca’s area.

"However, when they looked at more specific forms of language processing, for example of nouns versus verbs, they saw many more brain regions coming online.

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“'Those language regions that survive, when you average, are actually connectivity hubs,” says Skipper. “Those are the regions that coordinate lots of other regions in the brain.”
The researchers also scanned people’s brains as they watched movies. The films had been annotated so the team knew when characters were speaking and what they were saying, so they could see changes in brain activity as people processed language. Again, activation wasn’t confined to regions like Broca’s area, but encompassed up to 67 per cent of the brain.

"Evelina Fedorenko at the Massachusetts Institute of Technology disputes the work’s conclusions. She has studied a network of brain regions known as the multiple demand network, which she says is sometimes activated during language processing, but that isn’t specific to language. Instead, she says these areas “are active during diverse demanding tasks”, and that is what the team’s meta-analysis picked up.

"Skipper, however, says he and his colleagues don’t believe that such a fixed multiple demand network could exist anatomically. Rather, they believe that nearly any part of the brain can kick in as needed.

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"For example, Simonyan and her colleagues have used brain imaging to find six distinct communities of neurons involved in speech control, including in brain structures like the putamen and thalamus that are far removed from regions like Broca’s area. Simonyan has also been involved in work showing that a different set of regions is activated depending on whether people are saying meaningful sentences or meaningless syllables. For this reason, she describes the new study as “confirmatory” rather than “life-changing”.

"For Fedorenko, the key point about regions like Broca’s area is that they respond selectively to language. She says other brain regions can be involved, but those regions aren’t language specific.

"But Skipper doesn’t think that regions like Broca’s area are only selective for language. Most brain regions participate in many tasks, he says, something called neural reuse. “Any given ‘language region’ is talking to more than 40 per cent of the rest of the brain at any given moment, which means, by definition, that those other regions are language specific in those moments,” says Skipper."

Comment: this debate exists because the brain is so complex in its activities, it is difficult to sort out specificities of action. When sapiens appeared 315,000 years ago they had to communicate in some simple way with specific sounds and hand gestures. The sapiens brain handled that activity easily, but as sapiens learned more and finally spoke a reasonably simple language, the brain accommodated because it had the initial capacity to do so. Under God's design the sapiens brain arrived planned for future use. Now in the last 1,000 years of civilization our brain handles an enormous number of highly complexity tasks with no sign of running out of capacity! This is one of the best examples of speciation with preparation for future use.