Chapter 13 Neurolinguistics Flashcards
How many nerve cells in the brain
10 billion nerve cells, or neurons, arranged in complex networks. Each cell can be directly linked with up to 10,000 others.
“lower” brains structures (close to spinal cord)
shared by almost all animals.
maintain functions such as respiration, heart rate, and muscle coordination.
cortex (outermost layer)
This structure is absent in reptiles and amphibians, and makes up a higher proportion of the brain in primates and their closer evolutionary relatives than it does in other mammals.
folded in on itself, which increases its surface area.
what is a sulcus (plural: sulci)
The inward part of a cortical fold
what is a gyrus (plural: gyri).
the outward part of a cortical fold
what are fissures
Deep sulci.
The longitudinal fissure separates the
cerebral hemispheres.
what is the corpus callosum
A bundle of nerve fibres, the connection between the cerebral hemispheres
cerebral hemispheres
two sides of the brain, the left and right cerebral hemispheres are anatomically and functionally separate
control contralateral functions of the body, i.e. those on the opposite side
left cerebral hemisphere
controls analytic abilities, such as arithmetic. is primarily responsible for language
Right cerebral hemisphere
controls more holistic tasks, such as recognition of faces and melodies
Right-handed people
Most right-handed people are left-lateralized for language.
Right-handed people- left hemisphere removed
• If their left hemisphere is surgically removed (for example, to treat severe epilepsy), they typically cannot process complex syntactic patterns, but retain some comprehension ability.
Right handed people- right hemisphere removed
• If their right hemisphere is surgically removed, they have difficulty understanding jokes and metaphors (like He was wearing a loud tie).
Left handed people
tend to be less lateralized for language.
lobes
hemispheres are further divided into
lobes.
where is the central sulcus
behind the frontal lobe and in front of the parietal lobe.
where is the Sylvian fissure
above the temporal lobe, separates it from the frontal/parietal lobes
occipital lobe
not separated by a fissure, but falls behind the parietal lobe
4 lobes of the brain
Frontal lobe (at the front), Temporal lobe (at the bottom), occipital lobe (at the back), Parietal lobe (at the top)
autopsy
a traditional technique for studying the areas of the brain involved in different language disorders
Careful observations of a living patient’s behaviour are recorded; after death, damage to the brain is examined
Computerized axial tomography (CT scanning)
uses X-rays to provide a 3D static image of the brain, identifying lesions and tumours.
Positron emission tomography (PET)
uses a radioactive tracer to track glucose absorption in the brain, which is higher in areas of activity.
Functional magnetic resonance imaging (fMRI)
uses a powerful (and expensive!) magnet to measure blood deoxygenation, with no radioactive tracer.