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Some neurons are more active than others, even when they are positioned right next to each other and are one and the same neuron type. Researchers now have discovered the cause for this phenomenon.

According to a new study: "The human mirror system/motor speech system is not critical for speech perception. Temporal lobe structures, rather than motor structures, are the primary substrate for speech perception."

Scientists are reporting in the journal Science that they have identified specialized brain cells that help us understand what a speaker really means. These cells do this by keeping track of changes in the pitch of the voice. "We found that there were groups of neurons that were specialized and dedicated just for the processing of pitch," says Dr. Eddie Chang, a professor of neurological surgery at the University of California, San Francisco. Chang says these neurons allow the brain to detect "the melody of speech," or intonation, while other specialized brain cells identify vowels and consonants. "Intonation is about how we say things," Chang says. "It's important because we can change the meaning, even - without actually changing the words themselves." The identification of specialized cells that track intonation shows just how much importance the human brain assigns to hearing, says Nina Kraus, a neurobiologist who runs the Auditory Neuroscience Laboratory at Northwestern University. "Processing sound is one of the most complex jobs that we ask our brain to do," Kraus says. And it's a skill that some brains learn better than others, she says. Apparently, musicians, according to a study conducted by Kraus, are better than non-musicians at recognizing the subtle tonal changes found in Mandarin Chinese. On the other hand, recognizing intonation is a skill that's often impaired in people with autism, Kraus says. "A typically developing child will process those pitch contours very precisely," Kraus says. "But some kids on the autism spectrum don't. They understand the words you are saying, but they are not understanding how you mean it." The new study suggests that may be because the brain cells that usually keep track of pitch aren't working the way they should.

great video gives you sense of size

narrated lecture by a teacher

if you really want to understand it at the molecular level

An interesting slide shows overlay between monkeys' area for mirror neurons and Broca's area in humans

Seems to have a security feature that's locked me out: Forbidden You don't have permission to access /Page/docs/.../Corballis-presentation.pdf on this server.

Other, non-human primates have Broca's and Wernicke's areas in their brains, as do humans. In both species, the Broca's region represents non-linguistic hand and mouth movements. Evidence also suggests that both species may have mirror neurons in this region that are involved in understanding the actions and intentions of others. In both macaques and humans, this region is likely involved in producing orofacial expressions and in understanding the intentions behind orofacial expressions of others. In humans, it has evolved an additional communicative function, namely speech production. Interestingly however, it does not appear to be involved in monkey vocalizations, which are instead mediated by limbic and brainstem areas. In both species, the region represents non-linguistic hand and mouth movements. Evidence also suggests that both species may have mirror neurons in this region that are involved in understanding the actions and intentions of others. In both macaques and humans, this region is likely involved in producing orofacial expressions and in understanding the intentions behind orofacial expressions of others. In humans, it has evolved an additional communicative function, namely speech production. However, unlike in humans, Broca's area does not appear to be involved in monkey vocalizations, which are instead mediated by limbic and brainstem areas. Regarding Wernicke's area, which is responsible for language comprehension in humans, evidence suggests that the left superior temporal gyrus is specialized for processing species-specific calls in macaques, just as it is specialized for speech comprehension in humans.

The age at which children learn a second language can have a significant bearing on the structure of their adult brain, according to a new joint study by the Montreal Neurological Institute and Hospital -- The Neuro at McGill University and Oxford University. The study concludes that the pattern of brain development is similar if you learn one or two language from birth. However, learning a second language later on in childhood after gaining proficiency in the first (native) language does in fact modify the brain's structure, specifically the brain's inferior frontal cortex. The left inferior frontal cortex became thicker and the right inferior frontal cortex became thinner. The cortex is a multi-layered mass of neurons that plays a major role in cognitive functions such as thought, language, consciousness and memory. The study suggests that the task of acquiring a second language after infancy stimulates new neural growth and connections among neurons in ways seen in acquiring complex motor skills such as juggling. The study's authors speculate that the difficulty that some people have in learning a second language later in life could be explained at the structural level.

A 2013 joint study, conducted by the Montreal Neurological Institute and Hospital -- The Neuro at McGill University and Oxford University, concludes that the pattern of brain development is similar if you learn one or two languages from birth. However, learning a second language later on in childhood, after gaining proficiency in the first (native) language, does in fact, modify the brain's structure, specifically the brain's inferior frontal cortex. The left inferior frontal cortex became thicker and the right inferior frontal cortex became thinner. The cortex is a multi-layered mass of neurons that plays a major role in cognitive functions such as thought, language, consciousness and memory. The study suggests that the task of acquiring a second language after infancy stimulates new neural growth and connections among neurons in ways seen in acquiring complex motor skills such as juggling. The study's authors speculate that the difficulty that some people have in learning a second language later in life could be explained at the structural level. "The later in childhood that the second language is acquired, the greater are the changes in the inferior frontal cortex," said Dr. Denise Klein, researcher in The Neuro's Cognitive Neuroscience Unit and a lead author on the paper published in the journal Brain and Language. "Our results provide structural evidence that age of acquisition is crucial in laying down the structure for language learning."

Brain imaging studies have explored the neural mechanisms of recovery in adults following acquired disorders and, more recently, childhood developmental disorders. However, the neural systems underlying adult rehabilitation of neurobiologically based learning disabilities remain unexplored, despite their high incidence. Here we characterize the differences in brain activity during a phonological manipulation task before and after a behavioral intervention in adults with developmental dyslexia. Phonologically targeted training resulted in performance improvements in tutored compared to nontutored dyslexics, and these gains were associated with signal increases in bilateral parietal and right perisylvian cortices. Our findings demonstrate that behavioral changes in tutored dyslexic adults are associated with (1) increased activity in those left-hemisphere regions engaged by normal readers and (2) compensatory activity in the right perisylvian cortex. Hence, behavioral plasticity in adult developmental dyslexia involves two distinct neural mechanisms, each of which has previously been observed either for remediation of developmental or acquired reading disorders.

The more parents talk to their children, the faster those children's vocabularies grow and the better their intelligence develops. The problem seems to be cumulative. By the time children are two, there is a six-month disparity in the language-processing skills and vocabulary of toddlers from low-income families. Toddlers learn new words from their context, so the faster a child understands the words he already knows, the easier it is for him to attend to those he does not. Dr Anne Fernald, of Stanford, found that words spoken directly to a child, rather than those simply heard in the home, are what builds vocabulary. Plonking children in front of the television does not have the same effect. Neither does letting them sit at the feet of academic parents while the grown-ups converse about Plato. The effects can be seen directly in the brain. Kimberly Noble of Columbia University studies how linguistic disparities are reflected in the structure of the parts of the brain involved in processing language. Although she cannot yet prove that hearing speech causes the brain to grow, it would fit with existing theories of how experience shapes the brain. Babies are born with about 100 billion neurons, and connections between these form at an exponentially rising rate in the first years of life. It is the pattern of these connections which determines how well the brain works, and what it learns. By the time a child is three, there will be about 1,000 trillion connections in his brain, and that child's experiences continuously determine which are strengthened and which pruned. This process, gradual and more-or-less irreversible, shapes the trajectory of the child's life.And it is this gap, more than a year's pre-schooling at the age of four, which seems to determine a child's chances for the rest of his life.

Since his birth 33 years ago, Jonathan Keleher has been living without a cerebellum, a structure that usually contains about half the brain's neurons. Besides playing a vital role in balance and fine motor control, the cerebellum is also actively involved in higher functions, like using language, reading maps and planning. Emotional complexity is a challenge for Jonathan, says his sister, Sarah Napoline. She says her brother is a great listener, but isn't introspective. "He doesn't really get into this deeper level of conversation that builds strong relationships, things that would be the foundation for a romantic relationship or deep enduring friendships," she says. Jonathan also needed to be taught a lot of things that people with a cerebellum learn automatically, Sarah says: how to speak clearly, how to behave in social situations and how to show emotion. Yet Jonathan is now able to do all of those things. He's done it by training other areas of his brain to do the jobs usually done by the cerebellum.

Information about even the tiniest details of our daily lives zooms along neurons in our brains and is processed and saved in some predetermined location. How and what information is stored in the memory is in part dependent on whether an individual is a man or a woman.

Almost every language on the planet includes words that sound like the things they describe. Crash, yawn, glug… speech is just full of these onomatopoeias. And because they have their root in real things they're often easy to identify. Even a non-native speaker might recognise the Hindi "achhee" (a sneeze) or the Indonesian "gluk" (glug). Because these onomatopoeias are so widely encountered, easy to pick up, and convey information might they be the first form of language? That's the argument presented in a recent paper published in Animal Cognition. It points out that our ancestors would have begun encountering more and more noises that we could repeat. Tool use/ manufacture in particular, with its smashes and crashes, would be a prime source of onomatopoeias. Mimicking these sounds could have allowed early humans to "talk" about the objects; describing goals, methods, and objects. Might handing someone a rock and going "smash" been a way to ask them to make a tool? Perhaps different noises could even refer to different tools. Humans are good at extracting information from mimicked sounds. These sounds also trigger "mirror neurons" - parts of the brain that fire when we observe other people doing something - allowing us to repeat those actions. Seeing someone hold a rock a certain way and saying "smash" could have helped our ancestors teach the proper way to smash. But the biggest benefit would be the fact that you can communicate about these objects without seeing them. Having a sound for a tool would allow you to ask someone for it, even if they didn't have it on them. Given these advantages, it's easy to imagine how evolution would have favoured people who mimicked noises. Over time, this would have driven the development of more and more complex communication; until language as we recognise it emerged. Following this narrative, you can see (or maybe hear) how an a human ancestor with almost no language capability gradual

Dr. Joy Hirsch, head of Memorial Sloan-Kettering Hospital's functional M.R.I. Laboratory, and her graduate student, Karl Kim, found that second languages are stored differently in the human brain, depending on when they are learned. Babies who learn two languages simultaneously, and apparently effortlessly, have a single brain region for generating complex speech, researchers say. But people who learn a second language in adolescence or adulthood possess two such brain regions, one for each language. To explore where languages lie in the brain, Dr. Hirsch recruited 12 healthy bilingual people from New York City. Ten different languages were represented in the group. Half had learned two languages in infancy. The other half began learning a second language around age 11 and had acquired fluency by 19 after living in the country where the language was spoken. With their heads inside the M.R.I. machine, subjects thought silently about what they had done the day before using complex sentences, first in one language, then in the other. The machine detected increases in blood flow, indicating where in the brain this thinking took place. Activity was noted in Wernicke's area, a region devoted to understanding the meaning of words and the subject matter of spoken language, or semantics, as well as Broca's area, a region dedicated to the execution of speech, as well as some deep grammatical aspects of language. None of the 12 bilinguals had two separate Wernicke's areas, Dr. Hirsch said. But there were dramatic differences in Broca's areas, Dr. Hirsch said. In people who had learned both languages in infancy, there was only one uniform Broca's region for both languages, a dot of tissue containing about 30,000 neurons. Among those who had learned a second language in adolescence, however, Broca's area seemed to be divided into two distinct areas. Only one area was activated for each language. These two areas lay close to each other but were always separate, Dr. Hirsch s

A 2022 University of Cambridge study conducted by Sahakian, Langley, Chen, et al., and published in the journal _Neurology_, shows that that social isolation is linked to changes in brain structure and cognition - the mental process of acquiring knowledge - it even carries an increased risk of dementia in older adults. Previous research established that brain regions consistently involved in diverse social interactions are strongly linked to networks that support cognition, including the default mode network (which is active when we are not focusing on the outside world), the salience network (which helps us select what we pay attention to), the subcortical network (involved in memory, emotion and motivation) and the central executive network (which enables us to regulate our emotions). This particular study examined how social isolation affects grey matter - brain regions in the outer layer of the brain, consisting of neurons. It investigated data from nearly 500,000 people from the UK Biobank, with a mean age of 57. People were classified as socially isolated if they were living alone, had social contact less than monthly and participated in social activities less than weekly. The study also included neuroimaging (MRI) data from approximately 32,000 people. That data revealed that socially isolated people had poorer cognition, including in memory and reaction time, and lower volume of grey matter in many parts of the brain. These areas included the temporal region (which processes sounds and helps encode memory), the frontal lobe (which is involved in attention, planning and complex cognitive tasks) and the hippocampus - a key area involved in learning and memory, which is typically disrupted early in Alzheimer's disease. We also found a link between the lower grey matter volumes and specific genetic processes that are involved in Alzheimer's disease. Follow-ups with participants 12 years later showed that those who were socially isolated, but not