Language

Question 1

What are some forms of expressing language? What is speech, and how does it come naturally to humans?

Answer 1

Language can be expressed through gestures, writing, and speech. Speech is an audible form of communication based on sounds humans produce. Children raised in a normal language environment naturally learn to understand and speak without formal training.

Question 2

What is the difference between speech and reading/writing in terms of learning?

Answer 2

Speech is acquired naturally with little formal training, while reading and writing typically require years of formal education, making a significant portion of the world’s population illiterate.

Question 3

What are the key components involved in human sound production? and how does human sound production begin?

Answer 3

-Human sound production involves the coordination of over 100 muscles, including those controlling the lungs, larynx, and mouth, all controlled by the motor cortex.
-Human sound production starts when a person exhales air from the lungs, which passes through the larynx, also known as the voice box.

Question 4

What are vocal folds, and how do they contribute to sound production?

Answer 4

Vocal folds, also known as vocal cords, are two bands of muscle within the larynx that form a V shape. Sound is produced by vibrations in tightened vocal folds, with greater tension resulting in higher-frequency vibrations and higher-pitched sound.
-The space between the vocal folds is the glottis
(What we call the Adam’s apple in the neck is the larynx’s anterior wall of cartilage)

Question 5

How is the pitch of a sound determined in human speech?

Answer 5

The pitch of a sound in human speech is determined by the frequency of vocal fold vibrations, with greater tension in the vocal folds producing higher-pitched sounds.

Question 6

How is sound modified in the vocal tract during speech production?

Answer 6

Sound is modified at various stages of the vocal tract, including the pharynx, mouth, and nose. Rapid changes in the positions of the tongue, lips, and soft palate also modulate sound for speech

Question 7

What are phonemes, and how do they relate to language?

Answer 7

Phonemes are the fundamental sounds used in a language to build unique words. Different spoken languages have different phonemes, and research suggests that language may influence how people think.

Question 8

How do nonhuman primates, like chimpanzees, compare to humans in terms of vocalizations and language?

Answer 8

Nonhuman primates, such as chimpanzees, have a limited range of vocalizations compared to humans, who have highly creative language based on grammar rules, allowing for infinite word combinations and sentences. Chimpanzees mostly make stereotyped vocalizations, like alarm calls and pant-hoots, which are responses to specific behavioral situations.

Question 9

How does language acquisition (learning a language) typically proceed in all cultures?

Answer 9

Language acquisition follows a similar pattern in all cultures, starting with newborn gurgles that develop into babbling around 6 months of age. By 18 months of age, children understand about 150 words and can speak about 50. By 1–2 years of age, children’s speech has the tones, rhythm, and accent of the language they are exposed to

Question 10

What happens to an infant’s ability to distinguish sounds as they grow?

Answer 10

Infants begin to lose the ability to distinguish sounds they could previously discriminate, often influenced by the language spoken in their environment. an example is
a Japanese child’s difficulty discriminating the English “r” and “l” sounds because these sounds are not used in Japanese

Question 11

At what age do children typically start producing full sentences?

Answer 11

By the age of 3, children can produce full sentences and have acquired the tones, rhythm, and accent of their native language. and knows roughly 1000 words

Question 12

what happens to language acquisition after puberty?

Answer 12

Learning a second language becomes more difficult after puberty, suggesting a critical period for language acquisition

Question 13

What challenges do infants face when learning their native language? How do infants overcome the challenge of recognizing word boundaries in spoken language?

Answer 13

-Infants initially struggle with recognizing word boundaries and understanding spoken language due to the lack of reliable cues for word divisions.
-Infants employ statistical learning, which is recognizing that certain sound combinations are more likely than others, and they also use cues like syllable emphasis and prosody, such as “motherese” or baby talk, to aid language acquisition. –> When a low probability combination occurs, it suggests the possible location of a word boundary.

Question 14

What is “motherese,” and how does it assist infants in language learning?

Answer 14

“Motherese” is a speech style used by adults, often when talking to infants, characterized by slower speech, exaggerated intonation, and clearer articulation of vowel sounds. It helps infants learn speech sounds and patterns.

Question 15

At what age do infants typically recognize the sounds and words of their native language?

Answer 15

By around 1 year of age, infants can recognize the sounds and words of their native language, even though they may not fully understand their meanings.

Question 16

What did Ghislaine Dehaene-Lambertz et al. find regarding the brain response to spoken words in infants?

Answer 16

Ghislaine Dehaene-Lambertz et al. found, using fMRI, that even at the age of 3 months, the brain response to spoken words in infants is distributed in a manner similar to that in adults.

Question 17

Which brain regions are activated when infants listen to speech?

Answer 17

Listening to speech activates extensive areas in the temporal lobe, with the activation strongly biased toward the left hemisphere in infants.

Question 18

What does the early organization of auditory areas and lateralization for language in infants indicate?

Answer 18

The early organization of auditory areas and lateralization for language in infants do not show that the infant brain processes language the same as the adult brain, but indicates a similar pattern to that found in adults.

Question 19

what suggests that genetic factors play a role in susceptibility to language disorders?

Answer 19

the observation that speech and language disorders tend to run in families and are more likely to co-occur in identical twins than in fraternal twins suggests that genetic factors play an important role

Question 20

What is the KE family known for in the context of language disorders? What were the speech characteristics of affected KE family members?

Answer 20

The KE family is known for spanning three generations and having approximately half of its members affected by verbal dyspraxia, a condition that impairs coordinated muscular movements required for speech. Affected KE family members had largely unintelligible speech, leading them to use hand signs to supplement spoken language.

Question 21

Were the language problems in the KE family associated with general cognitive impairments?

Answer 21

No, the language difficulties observed in the KE family were specific to language and not associated with general cognitive impairments, as affected members with normal IQs also experienced language problems.

Question 22

What did brain scans reveal about affected KE family members?

Answer 22

Brain scans showed structural abnormalities in motor areas such as the motor cortex, cerebellum, and striatum (caudate and putamen) in affected KE family members compared to unaffected members.

Question 23

What distinguishes the inheritance pattern of the KE family’s language disorder from previously observed inherited language disorders? What is the name of the mutated gene responsible for the language disorder in the KE family? Is FOXP2 considered the sole “language gene”?

Answer 23

-The inheritance pattern in the KE family is consistent with the mutation of a single gene, unlike previously observed disorders that appeared to involve multiple genes.
-This gene appears to affect the development of the motor cortex, cerebellum, and striatum; there are particular deficits in the muscular control of the lower face
-The mutated gene is identified as FOXP2.
-No, FOXP2 is not considered the sole “language gene,” but it does appear to be one critical gene involved in language.

Question 24

How many copies of the FOXP2 gene do individuals typically have, and what is the consequence of a mutation in one copy?

Answer 24

Individuals typically have two copies of the FOXP2 gene, and a mutation in either one is sufficient to produce severe language deficits

Question 25

What other function is associated with the FOXP2 gene, besides its role in language?

Answer 25

The FOXP2 gene codes for a transcription factor responsible for turning other genes on and off, potentially influencing numerous genes involved in language.

Question 26

where is FOXP2 found in animals

Answer 26

FOXP2 is a gene found in many animals, and in highly vocal songbirds, it is strongly expressed in brain areas involved in song learning.

Question 27

How does the human FOXP2 protein differ from that of chimpanzees, gorillas, and rhesus monkeys?

Answer 27

the human FOXP2 protein differs from that of chimpanzees, gorillas, and rhesus monkeys by only two amino acids.

Question 28

When did the mutations that differentiate the human and nonhuman primate FOXP2 genes occur?

Answer 28

The mutations differentiating human and nonhuman primate FOXP2 genes are estimated to have occurred about 200,000 years ago.

Question 29

What is the speculation regarding the role of FOXP2 in human evolution?

Answer 29

It is speculated that a small and relatively recent mutation in the FOXP2 gene set humans on a path toward developing language, which was needed for higher cognitive function and the development of human culture.

Question 30

What is specific language impairment (SLI)? What percentage of 6-year-olds in the United States have specific language impairment (SLI)?

Answer 30

-SLI is a developmental delay in language mastery that may persist into adulthood, not associated with hearing difficulty or general developmental delays. These children have difficulty learning and using words, especially verbs. Because more than 50% of children with SLI have a parent or sibling with the condition, there appears to be a strong genetic component
-about 7%

Question 31

What genes have been implicated in specific language impairment (SLI) besides FOXP2?

Answer 31

CNTNAP2 and KIAA0319

Question 32

What is the function of the CNTNAP2 gene?

Answer 32

-CNTNAP2 codes for a neurexin protein involved in brain development and the proper location of potassium channels in developing neurons.
-these are proteins on the presynaptic side of synapses that serve to hold the presynaptic and postsynaptic elements together

Question 33

What is the function of the KIAA0319 gene?

Answer 33

KIAA0319 is thought to be critical for neuronal migration during neocortical development and normal adult neuronal function.

Question 34

What is dyslexia, and how common is it? Is there a genetic link to dyslexia?

Answer 34

-Dyslexia is a disorder characterized by difficulty learning to read despite normal intelligence and training. It is estimated to occur in 5-10% of individuals and is slightly more common in males than females.
-Yes, dyslexia appears to have a strong genetic link. Children of dyslexic parents have about a 30% chance of being dyslexic, and 30-50% of siblings of dyslexic individuals also have dyslexia.

Question 35

Are there specific genes associated with dyslexia? What is the comorbidity rate between dyslexia and SLI, and what does it suggest? How does dyslexia relate to neocortical development?

Answer 35

-Yes, one of the genes often associated with dyslexia is KIAA0319, which is also implicated in specific language impairment (SLI).
-Dyslexia and SLI have a comorbidity rate of about 40-50%, suggesting they may share similar causes or represent different manifestations of the same deficit.
-Dyslexia, like SLI, appears to involve deviations from the normal pattern of neocortical development.

Question 36

What is aphasia?

Answer 36

Aphasia is the partial or complete loss of language abilities following brain damage, often without the loss of cognitive faculties or the ability to move the muscles used in speech.

Question 37

What was the common belief during the Greek and Roman Empires regarding speech and brain disorders? Who proposed a relatively modern theory of aphasia around 1770?

Answer 37

-It was commonly thought that the tongue controls speech and that speech disorders originate there rather than in the brain.

-Johann Gesner proposed a theory of aphasia, describing it as the inability to associate images or abstract ideas with their expressive verbal symbols, attributing it to brain damage resulting from disease.

Question 38

In 1825, which French physician proposed that speech is specifically controlled by the frontal lobes?

Answer 38

Jean-Baptiste Bouillaud proposed that speech is specifically controlled by the frontal lobes.

Question 39

What significant observation did Simon Alexandre Ernest Aubertin make in 1861 regarding the frontal lobes and speech?

Answer 39

Aubertin discovered that pressure on the exposed frontal lobe of a man interfered with his speech, leading to the inference that a specific cortical area in the frontal lobe is involved in speech.

Question 40

What did Paul Broca’s patient, known as “Tan,” suffer from, and what was discovered after his death? In what hemisphere of the brain did Paul Broca propose that language expression is primarily controlled? What is the region in the dominant left frontal lobe associated with articulate speech?

Answer 40

-“Tan” was almost entirely unable to speak, and after his death, a lesion in the frontal lobes was found by Paul Broca.
-Broca proposed that language expression is primarily controlled by the left hemisphere of the brain
-The region is called Broca’s area. If one hemisphere is thought to be more heavily involved in a particular task, it is said to be dominant

Question 41

What is the Wada procedure, and what does it reveal about language dominance in the brain?

Answer 41

The Wada procedure involves anesthetizing a single hemisphere of the brain. It shows that in most cases, anaesthesia of the left hemisphere disrupts speech, while the right hemisphere does not.

Question 42

Where is Wernicke’s area located in the brain?

Answer 42

On the superior surface of the temporal lobe between the auditory cortex and the angular gyrus.

Question 42

What is Broca’s aphasia? What are the characteristics of Broca’s aphasia?

Answer 42

-Broca’s aphasia, also known as motor or nonfluent aphasia, refers to a syndrome where a person struggles with speaking but can comprehend language when heard or read.
-Broca’s aphasia is characterized by difficulty in producing speech, anomia (inability to find words), telegraphic speech mainly contain content words (nouns, verbs, and adjectives
carrying content specific to the sentence), with missing function words (there are no ifs, ands, or buts), agrammatism (difficulty constructing grammatically correct sentences), and paraphasic errors (substituting incorrect sounds or words).

Question 43

Does Broca’s aphasia affect comprehension?

Answer 43

Broca’s aphasia typically does not severely affect comprehension, but deficits may be observed in response to tricky questions or complex instructions.

Question 43

What are the possible explanations for Broca’s aphasia? and how is Broca’s aphasia described in terms of language disturbance?

Answer 43

-There are two main theories: Wernicke’s theory suggests that Broca’s area is involved in storing motor commands for articulating word sounds. An alternative theory proposes that Broca’s area plays a role in constructing grammatical sentences.
-Broca’s aphasia is considered a language disturbance toward the motor end of the language system, where language comprehension is relatively intact, but language production is impaired.

Question 44

Describe the differences between Broca’s aphasia and Wernicke’s aphasia. and discuss what happens if theres a lesion in wernickes area

Answer 44

-In Broca’s aphasia, speech is disturbed while comprehension is relatively intact. In Wernicke’s aphasia, speech is fluent, but comprehension is poor.
-A lesion in Wernicke’s area produces comprehension problems because it’s responsible for transforming sounds into words. Speech production, however, remains unaffected because Broca’s area can still drive the muscles required for speech.

Question 45

How do Wernicke aphasics typically respond to questions and commands? Provide an example of a categorical error made by Wernicke aphasics.

Answer 45

-Wernicke aphasics have difficulty comprehending questions and commands, often responding with unintelligible speech. Comprehension is assessed through nonverbal tasks. Wernicke’s aphasics also make far more paraphasic errors
-Wernicke aphasics might use an incorrect word that is categorically similar to the correct word, such as saying “knee” instead of “elbow.”

Question 46

How do Wernicke aphasics react to their own speech and the speech of others?

Answer 46

Wernicke aphasics often appear undisturbed by their own unintelligible speech and the speech of others, indicating a lack of comprehension.

Question 47

What does speech in Wernicke’s aphasia suggest about Broca’s area and speech production?

Answer 47

Speech in Wernicke’s aphasia suggests that Broca’s area and the system responsible for speech production may run without control over content, resulting in incoherent speech patterns.

Question 48

What is the suggested function of Wernicke’s area besides speech comprehension?

Answer 48

Wernicke’s area may play a critical role in relating incoming sounds to their meaning and storing memories of the sounds that make up words.

Question 49

What is the Wernicke–Geschwind model of language processing?

Answer 49

The Wernicke–Geschwind model is a theory that outlines the neural basis of language processing in the brain. It includes key components such as Broca’s area, Wernicke’s area, the arcuate fasciculus, and the angular gyrus, as well as sensory and motor areas involved in language reception and production.

Question 50

In the context of the Wernicke-Geschwind model, what happens during the repetition of spoken words?

Answer 50

According to the model, when someone hears spoken words, the auditory system processes the sounds, and neural signals reach the auditory cortex. These sounds are processed in Wernicke’s area to understand them as meaningful words. To repeat the words, signals are transmitted from Wernicke’s area to Broca’s area via the arcuate fasciculus. In Broca’s area, the words are translated into codes for the required muscular movements for speech.

Question 51

How does the visual information for reading text get processed in the brain? What role does the angular gyrus play in reading written text aloud?

Answer 51

-Visual signals are processed by the visual system through the striate cortex (primary visual cortex) and higher-order visual cortical areas, which analyze and interpret the visual input
-the angular gyrus, located at the junction of the occipital, parietal, and temporal lobes, is responsible for transforming visual information into a format that activates Wernicke’s area as if the words were spoken, allowing for comprehension.

Question 52

Describe the progression of language processing during the task of reading written text aloud.

Answer 52

1. Visual processing begins in the striate cortex and higher-order visual cortical areas.
2. Visual signals are then transmitted to the angular gyrus, where transformation occurs to evoke the same pattern of activity in Wernicke’s area as if the words were spoken.
3. From Wernicke’s area, language processing continues to Broca’s area.
4. Finally, Broca’s area coordinates with the motor cortex to produce the motor movements necessary for speech production during reading.

Question 53

What are some oversimplifications in the Wernicke-Geschwind model? Are the functional distinctions between regions in cortical processing as clear as implied by the model?

Answer 53

-The model suggests that words read need to be transformed into a pseudo-auditory response, but this is not always the case. Visual information can reach Broca’s area directly from the visual cortex without going through the angular gyrus. Additionally, the model does not consider damage to subcortical structures like the thalamus and caudate nucleus, which can affect language.
-No, in cortical processing, the sharp functional distinctions between regions, as implied by the model, do not always exist.

Question 54

How does the severity of aphasias depend on damage beyond Broca’s and Wernicke’s areas?

Answer 54

The severity of Broca’s and Wernicke’s aphasias depends on how much cortex is damaged beyond the limits of Broca’s and Wernicke’s areas.

Question 55

What role do subcortical structures play in aphasia?

Answer 55

Subcortical structures such as the thalamus and caudate nucleus can influence aphasia, but they are not included in the Wernicke-Geschwind model.

Question 56

Despite its problems, why is the Wernicke-Geschwind model still useful? What developments occurred in language models in the latter half of the twentieth century?

Answer 56

-The Wernicke-Geschwind model is still useful in clinical contexts because of its simplicity and approximate validity.

-In the latter half of the twentieth century, numerous more elaborate language models were developed to account for the complexities of language and brain processing, as well as the shortcomings of the Wernicke-Geschwind model. These models involve parallel pathways with distinct but interacting functions.

Question 57

Describe the main characteristics of conduction aphasia.

Answer 57

-conduction aphasia
-aphasia resulting from a lesion disconnecting the frontal and superior temporal cortex areas
-comprehension is typically good, and speech is fluent. Patients can express themselves through speech without difficulty. The primary deficit is difficulty in repeating words, with paraphasic errors often occurring
-repetition usually best with nouns and short expressions but it may fail entirely if the spoken words are functions word, polysyllobic words or nonsense sounds

Question 58

How does a person with conduction aphasia comprehend sentences they read aloud?

Answer 58

A person with conduction aphasia can comprehend sentences they read aloud, even if the spoken words contain paraphasic errors. This suggests that comprehension is good, and the deficit occurs in the connection between regions involved in comprehension and speech.

Question 59

What happens when a person learns two languages at the same time and has a stroke?

Answer 59

If someone learns two languages simultaneously to similar fluency levels, a lesion (due to a stroke, for example) may produce similar deficits in both languages.

Question 60

How does the timing of language acquisition affect language preservation after a stroke?

Answer 60

When languages are learned at different stages of life, it’s more likely that one language will be affected more than the other. The second language may involve different neural populations compared to the first language.

Question 61

What does the study of language deficits in deaf sign language users suggest about language processing in the brain? and what is sign language Wernicke’s aphasia?

Answer 61

-The study of language deficits in deaf individuals who use sign language suggests some universality in language processing in the brain. Lesions in the left hemisphere can cause language deficits similar to those in verbal aphasia, even though the problem is not related to motor control but rather to the use of hand movements for language expression.
-There are cases analogous to Broca’s aphasia in which comprehension is good but the ability to “speak” through sign language is severely impaired. Importantly, the ability to move the hands is not impaired (i.e., the problem is not with motor control). Rather, the deficit is specific to the use of hand
movements for the expression of language
-Sign language Wernicke’s aphasia is a condition in which a patient can sign fluently but with many mistakes and has difficulty comprehending the signing of others.

Question 62

What was observed in the case of a hearing man with deaf parents who learned both sign language and verbal language?

Answer 62

In the case of a hearing man with deaf parents, it was observed that after a left hemispheric stroke, his global aphasia initially affected both verbal and sign languages, and both languages recovered together over time.

Question 63

Are the brain areas responsible for sign language and verbal language entirely separate?

Answer 63

No, there is evidence to suggest that the brain areas responsible for sign language and verbal language can overlap, and lesions in different locations of the left hemisphere can produce signing aphasia and speaking aphasia.

Question 64

What are split-brain studies, and what do they involve? How did split-brain studies contribute to our understanding of language differences in the cerebral hemispheres?

Answer 64

-Split-brain studies involve surgically disconnecting the cerebral hemispheres, and they provide valuable insights into the differences in language processing between the two hemispheres of the brain.
-Split-brain studies demonstrated that language processing is not handled equally by the two hemispheres and provided valuable insights into the specific roles of each hemisphere in language processing.

Question 65

Why was the corpus callosum cut in certain individuals with severe epilepsy? How did Gazzaniga ensure that visual stimuli were presented to only one cerebral hemisphere?

Answer 65

-Surgeons cut the corpus callosum to prevent the spread of epileptic activity from one hemisphere to the other, as a treatment for severe epilepsy.
-Gazzaniga used a device with a camera-like shutter to flash pictures or words for a fraction of a second. This method allowed only one hemisphere to “see” the stimulus based on the eye’s field of view

Question 66

Which hemisphere is usually dominant for language in most people?

Answer 66

left hemisphere

Question 67

What happens if an image is shown only in the left visual field of a split-brain person?

Answer 67

If an image is shown only in the left visual field, a split-brain person cannot describe it and usually says that nothing is there.

Question 68

What is the consequence of the left hemisphere’s control over speech in split-brain individuals?

Answer 68

The consequence is that split-brain individuals are unable to describe anything to the left of their visual fixation point.

Question 69

Can split-brain individuals describe objects felt only by the left hand? What happens if an image is shown only in the left visual field of a split-brain person?

Answer 69

-No, split-brain individuals cannot describe objects felt only by the left hand, This absence of response is a consequence (and demonstration) of the fact that the left hemisphere controls speech in most people.
-If an image is shown only in the left visual field, a split-brain person cannot describe it and usually says that nothing is there. they can repeat or describe numbers, words, and pictures visually presented only in the right visual field because the left hemisphere is usually dominant for language so the right side isn’t communicating with left side.

Question 70

What is the significant difference between the right hemisphere and the left hemisphere regarding language abilities? How can it be demonstrated that the right hemisphere has language comprehension?

Answer 70

-The right hemisphere cannot speak but does have language comprehension.
-Words seen by her left hemisphere could be spoken but not written. Conversely, she could write but not speak words shown to her right hemisphere
-The right hemisphere can read and understand numbers, letters, and short words, as long as the response is nonverbal.
-right hemisphere able to write but not speak

Question 71

What experiment suggests that the right hemisphere understands complex pictures despite its inability to express it verbally?

Answer 71

In an experiment, a subject saw a series of pictures in her left visual field, including a nude photo, and although she claimed to see nothing, she began to laugh, indicating some level of comprehension.

Question 72

What are some tasks in which the right hemisphere appears to be more skilled than the left hemisphere?

Answer 72

The right hemisphere is better at drawing or copying figures with three-dimensional perspective, solving complex puzzles with the left hand, and perceiving nuances in sound.

Question 73

What do the results of split-brain studies suggest about the two hemispheres?

Answer 73

The results demonstrate that the two hemispheres can function as independent brains with different language abilities.

Question 74

What anatomical differences between the two hemispheres were noted for language? and what’s the number of right handed people

Answer 74

-It was noted that the left Sylvian fissure is longer and less steep than the right.
-about 65% of brains, the left planum temporale was larger than the right, whereas in only about 10% of brains, the right was larger.
-A portion of Broca’s area also tends to be larger in the left hemisphere.
-more than 90% humans right-handed

Question 75

What brain region presently appears to be the best predictor of language-dominant hemisphere? What is surprising about the insula’s role in language and its relationship with hemispheric dominance?

Answer 75

-The insula, which is the cerebral cortex within the lateral sulcus between the temporal and parietal lobes.

Question 76

What were the three main categories of effects observed during Wilder Penfield’s electrical brain stimulation studies related to speech? What happened when the motor cortex in the area controlling the mouth and lips was stimulated during Penfield’s experiments? then stimulation in Broca’s area, posterior parietal lobe near Sylvian fissure and temporal lobe

Answer 76

-The three main categories of effects were vocalizations, speech arrest, and speech difficulties similar to aphasia.

-Stimulation of the motor cortex controlling the mouth and lips caused immediate speech arrest for strong stimulation and speech hesitation from weak stimulation.

-Broca’s area–> Stimulation of the motor cortex controlling the mouth and lips caused immediate speech arrest due to muscle activation.

-In posterior parietal lobe near Sylvian fissure and temporal lobe: word confusion and speech arrest

Question 77

What conclusions can be drawn from electrical stimulation studies in the brain?

Answer 77

Conclusions from electrical stimulation studies include: 1) Considerable variability in language areas among individuals. 2) Some cortical areas may serve untested roles in language. 3) Nearby stimulation sites can have different effects, while distant sites can produce similar effects.

Question 78

What additional brain regions and structures are implicated in language processing based on electrical stimulation studies?

Answer 78

Electrical stimulation studies suggest that language areas may extend beyond the cortex to include parts of the thalamus and striatum. They also indicate that other cortical areas beyond Broca’s and Wernicke’s areas are involved in language processing.

Question 79

How does electrical stimulation affect different aspects of language in the brain?

Answer 79

Electrical stimulation of various cortical locations can selectively interfere with different aspects of language, including naming, reading, or repetition of facial movements. This suggests that language processing is distributed and not limited to specific regions

Question 80

What is surprising about the extent of brain activation observed in the Lehericy fMRI experiment recording during three different language tasks?

Answer 80

The surprising aspect is the extent of bilateral brain activation, even in individuals with a strongly dominant left hemisphere for language, suggesting more activity in the nondominant hemisphere than previously thought.

Question 81

In a PET imaging study, what did researchers measure to observe differences in brain activity related to words and speech production?

Answer 81

Researchers measured cerebral blood flow. They had subjects either look at words displayed on a computer or listen to words being read aloud. Visual stimuli activated the striate cortex and extrastriate cortex, while auditory stimuli activated primary and secondary auditory cortex. Notably, areas in extrastriate cortex and secondary auditory cortex responded specifically to words. However, visual stimuli did not significantly increase activity in the angular gyrus and Wernicke’s area, contrary to the Wernicke–Geschwind model

Question 82

What tasks were studied with PET imaging to examine brain activity during word repetition, and what did the brain activity patterns indicate?

Answer 82

PET imaging examined brain activity during the tasks of repeating spoken words and generating words (noun-verb associations). Brain activity patterns during word repetition indicated high levels of activity in primary motor cortex, the supplementary motor area, and increased blood flow around the Sylvian fissure near Broca’s area. However, Broca’s area activity may not have shown up in the images

Question 83

What brain areas were activated during the noun-verb association task (“generating words”) according to the PET images, and what do these findings suggest about brain organization for language?

Answer 83

The PET images showed increased activity in the left inferior frontal area, anterior cingulate gyrus, and posterior temporal lobe during the noun-verb association task (“generating words”). These findings suggest that distinct brain areas are involved in storing information about different categories of objects, and brain damage can lead to category-specific losses in the ability to name objects. It raises questions about how the brain processes various categories of words and integrates this information into a unified understanding of language.