Posts tagged inferior frontal gyrus

Posts tagged inferior frontal gyrus

The brains of jazz musicians engrossed in spontaneous, improvisational musical conversation showed robust activation of brain areas traditionally associated with spoken language and syntax, which are used to interpret the structure of phrases and sentences. But this musical conversation shut down brain areas linked to semantics - those that process the meaning of spoken language, according to results of a study by Johns Hopkins researchers.
The study used functional magnetic resonance imaging (fMRI) to track the brain activity of jazz musicians in the act of “trading fours,” a process in which musicians participate in spontaneous back and forth instrumental exchanges, usually four bars in duration. The musicians introduce new melodies in response to each other’s musical ideas, elaborating and modifying them over the course of a performance.
The results of the study suggest that the brain regions that process syntax aren’t limited to spoken language, according to Charles Limb, M.D., an associate professor in the Department of Otolaryngology-Head and Neck Surgery at the Johns Hopkins University School of Medicine. Rather, he says, the brain uses the syntactic areas to process communication in general, whether through language or through music.
Limb, who is himself a musician and holds a faculty appointment at the Peabody Conservatory, says the work sheds important new light on the complex relationship between music and language.
"Until now, studies of how the brain processes auditory communication between two individuals have been done only in the context of spoken language," says Limb, the senior author of a report on the work that appears online Feb. 19 in the journal PLOS ONE. “But looking at jazz lets us investigate the neurological basis of interactive, musical communication as it occurs outside of spoken language.
"We’ve shown in this study that there is a fundamental difference between how meaning is processed by the brain for music and language. Specifically, it’s syntactic and not semantic processing that is key to this type of musical communication. Meanwhile, conventional notions of semantics may not apply to musical processing by the brain."
To study the response of the brain to improvisational musical conversation between musicians, the Johns Hopkins researchers recruited 11 men aged 25 to 56 who were highly proficient in jazz piano performance. During each 10-minute session of trading fours, one musician lay on his back inside the MRI machine with a plastic piano keyboard resting on his lap while his legs were elevated with a cushion. A pair of mirrors was placed so the musician could look directly up while in the MRI machine and see the placement of his fingers on the keyboard. The keyboard was specially constructed so it did not have metal parts that would be attracted to the large magnet in the fMRI.
The improvisation between the musicians activated areas of the brain linked to syntactic processing for language, called the inferior frontal gyrus and posterior superior temporal gyrus. In contrast, the musical exchange deactivated brain structures involved in semantic processing, called the angular gyrus and supramarginal gyrus.
"When two jazz musicians seem lost in thought while trading fours, they aren’t simply waiting for their turn to play," Limb says. "Instead, they are using the syntactic areas of their brain to process what they are hearing so they can respond by playing a new series of notes that hasn’t previously been composed or practiced."
Brain training works, but just for the practiced task
Search for “brain training” on the Web. You’ll find online exercises, games, software, even apps, all designed to prepare your brain to do better on any number of tasks. Do they work? University of Oregon psychologists say, yes, but “there’s a catch.”
The catch, according to Elliot T. Berkman, a professor in the Department of Psychology and lead author on a study published in the Jan. 1 issue of the Journal of Neuroscience, is that training for a particular task does heighten performance, but that advantage doesn’t necessarily carry over to a new challenge.
The training provided in the study caused a proactive shift in inhibitory control. However, it is not clear if the improvement attained extends to other kinds of executive function such as working memory, because the team’s sole focus was on inhibitory control, said Berkman, who directs the psychology department’s Social and Affective Neuroscience Lab.
"With training, the brain activity became linked to specific cues that predicted when inhibitory control might be needed," he said. "This result is important because it explains how brain training improves performance on a given task — and also why the performance boost doesn’t generalize beyond that task."
Sixty participants (27 male, 33 females and ranging from 18 to 30 years old) took part in a three-phase study. Change in their brain activity was monitored with functional magnetic resonance imaging (fMRI).
Half of the subjects were in the experimental group that was trained with a task that models inhibitory control — one kind of self-control — as a race between a “go” process and a “stop” process. A faster stop process indicates more efficient inhibitory control.
In each of a series of trials, participants were given a “go” signal — an arrow pointing left or right. Subjects pressed a key corresponding to the direction of the arrow as quickly as possible, launching the go process. However, on 25 percent of the trials, a beep sounded after the arrow appeared, signaling participants to withhold their button press, launching the stop process.
Participants practiced either the stop-signal task or a control task that didn’t affect inhibitory control every other day for three weeks. Performance improved more in the training group than in the control group.
Neural activity was monitored using functional magnetic resonance imaging (fMRI), which captures changes in blood oxygen levels, during a stop-signal task. MRI work was done in the UO’s Robert and Beverly Lewis Center for Neuroimaging. Activity in the inferior frontal gyrus and anterior cingulate cortex — brain regions that regulate inhibitory control — decreased during inhibitory control but increased immediately before it in the training group more than in the control group.
The fMRI results identified three regions of the brain of the trained subjects that showed changes during the task, prompting the researchers to theorize that emotional regulation may have been improved by reducing distress and frustration during the trials. Overall, the size of the training effect is small. A challenge for future research, they concluded, will be to identify protocols that might generate greater positive and lasting effects.”Researchers at the University of Oregon are using tools and technologies to shed new light on important mechanisms of cognitive functioning such as executive control,” said Kimberly Andrews Espy, vice president for research and innovation and dean of the UO Graduate School. “This revealing study on brain training by Dr. Berkman and his team furthers our understanding of inhibitory control and may lead to the design of better prevention tools to promote mental health.”

It’s the way you tell em’: Study discovers how the brain controls accents and impersonations
A study, led by Royal Holloway University researcher Carolyn McGettigan, has identified the brain regions and interactions involved in impersonations and accents.
Using an fMRI scanner, the team asked participants, all non-professional impressionists, to repeatedly recite the opening lines of a familiar nursery rhyme either with their normal voice, by impersonating individuals, or by impersonating regional and foreign accents of English.
They found that when a voice is deliberately changed, it brings the left anterior insula and inferior frontal gyrus (LIFG) of the brain into play. The researchers also discovered that when comparing impersonations against accents, areas in the posterior superior temporal/inferior parietal cortex and in the right middle/anterior superior temporal sulcus showed greater responses.
“The voice is a powerful channel for the expression of our identity – it conveys information such as gender, age and place of birth, but crucially, it also expresses who we want to be,” said lead author Carolyn McGettigan from the Department of Psychology at Royal Holloway.
“Consider the difference between talking to a friend on the phone, talking to a police officer who’s cautioning you for parking violation, or speaking to a young infant. While the words we use might be different across these settings, another dramatic difference is the tone and style with which we deliver the words we say. We wanted to find out more about this process and how the brain controls it.”
While past work has found that listening to voices activates regions of the temporal lobe of the brain, no research had explored the brain regions involved in controlling vocal identity before this study.
“Our aim is to find out more about how the brain controls this very flexible communicative tool, which could potentially lead to new treatments for those looking to recover their own vocal identity following brain injury or a stroke, ” said Carolyn.
Researchers use magnetic pulses to brain to reduce overly optimistic tendencies
Scientists have known for many years that human beings, as a general rule, are an overly optimistic bunch. We close our eyes to statistics suggesting our eating habits may be killing us, ignore warnings about texting while driving and almost always believe things will come out all right in the end if we’ll just hang in there, despite sometimes obvious indications to the contrary. Research has suggested that two specific symmetrically opposite parts of the brain influence our optimism or pessimism, but until now haven’t been able to offer direct proof. Now however, new research by a group of neuroscientists has found, as they describe in their paper published in the Proceedings of the National Academy of Sciences, that turning off one of these areas via magnetic pulses dramatically reduces overly optimistic tendencies.