What clients are rehabilitated for communication disorders?
Patients who already have language skills (typically older adults)
The order of structures in a neuron (peripheral nervous system):
- dendrites
- nucleus
- soma
- axon
- myelin sheath
- Schwann cell
- node of Ranvier
- …
axon terminal
Cell bodies in neurons are considered _ matter
grey
Axons in neurons are considered _ matter
white
Fibre tracts a.k.a.
axons
Fibre tracts can range from 1 mm to _
1 m long
Between the axons are covered with myelin sheath, and are separated by
Nodes of Ranvier
_ control myelination in the peripheral n ervous system
Schwann cells
control myelination in the central nervous system
oligodendrocytes
Action potentials are _ signals
electrochemical
_ nerves move from the central nervous system, whereas _ nerves move to the central nervous system
Efferent/motor move from, afferent/perception move to
The hemispheres and lobes are a part of the
cerebrum
The reticular formation is involved with _
levels of alertness and consciousness
The reticular formation is a structure located in the
brain stem
The _ is involved with coordination of movement, motor learning, posture, and other aspects not completely known
cerebellum
According to Donald Hebb, _ that wire together, fire together
neural circuits
Action potentials tend to skip across axons, in a _ fashion
saltatory
The _ fibres connect lobes to other lobes
association
Neural development is mediated by
genetics
Newborn neurons develop mostly _ birth (location and connectivity determined _)
before birth;
determined in utero
Neural development continues after birth. True or false?
True
Considering the example of a family of multilinguists with an advanced Perisylvian fissure, this aspect of their neurology would be explained due to their _
neural development
According to the _ syndrome, seizures are due to the environment, whether from hot weather, fever, etc.
Dravet
Neural changes are due to external stimuli/sensory, according to the _ aspect of neurology
neuroplasticity
Neuroplasticity is involved with changes due to _, or responses
internal reorganization
Most neurons are developed by the _ gestational week
25th week/8 months, 1 week
Possible neurogenesis occurs later in the hippocampus, olfactory region, and _ during prenatal development
cerebellum
Neural tubes differentiate into _
various parts of the brain - cerebrum, brain stem, etc.
The greatest increase in surface and folding of the cerebral cortex occurs during the _ period
prenatal period
A _% increase in brain size occurs in the first 2 years
350
Glial cells, synaptic growth, myelination result in brain growth _-natally
post
Neurons migrate to various regioins and then _ guide axons to synapse with other neurons
growth cones
Glial cells are _ cells in neurology
support
Pruning occurs postnatally, also referred to as preprogrammed cell death or _, which involves the less efficient or redundant _ die off
apoptosis;
neural pathways
What is often a circumstance of clients with brain damage post-injury?
needing to be mroe deliberate in their actions, since they likely cannot rely on automated ones due to neural pathway and/or myelination damages
_ strategies appear helpful when dealing with a client with brain damage post-injury
Compensatory strategies
e.g., pre-empting phrases to get an answer, such as “do you want to go for a drive in the _?”
If asking about compensatory strategies in the environment as accounting for change, what does this suggest about changes in the brain?
there are no endogenous changes in the brain
In neural damage post-injury, damage can occur to both the cell body and the
axons
_ in damaged tissue is due to an impaired blood-brain barrier
swelling, or aedema
Swelling/aedema may be indicative of a
potential clot
Infiltration of infectionfighting cells in the brain post-injury is known as
neutrophils
After _, swelling starts to reduce in neural processes post-injury, which suggests why progress is often visible later on, despite poor functioning immediately after the incident
1 week
_ travel to the site of lesion and engulfs debris even as soon as 24 hours post-injury in the brain
microglia
_ form scar tissue in the brain around smaller lesions
Astrocytes
Axonal regeneration is better in the _ than the _, perhaps due to a growth protein present in _ but not in _
PNS more than CNS, with growth protein more present in PNS than CNS
Schwann cells exist in the _NS, whereas _ cells exist in the _NS
PNS
oligodendrocytes in CNS
The great thing about neural processes post-injury is that adjacent neuronal tissue may
take on new functions or reorganize across hemispheres
_ is the creation of new neurons
neurogenesis
Neuronal _ is the changing of neuronal structures as a part of neuroplasticity
migration
Dendritic _ occurs along with axon and dendritic growth, myelination and pruning in typical neuroplasticity
arborization
the development of new synapses in neuroplasticity is known as
synaptogenesis
“Neurons that fire together, wire together” is donald Hebb’s description of
the development of neuronal circuits
Cortical fields/circuits are involved in learning and neuroplasticity by their
establishment and/or modification
Factors affecting plasticity and learning include: genetics sensory and motor experience drugs neurotropic factors rewards aging stress diet magnetic/electrical stimulation exercise and
pre-injury learning!
The most influential neurotropic factor that affects plasticity and learning is _, which encourages neural functioning
brain-derived neurotropic factor (BDNF)
The single most replicable finding of what affects plasticity and learning: greater and improvement and change in adults is found in _
stimulating and complex environments
What does the most replicable finding in factors of plasticity and learning not hold for, and why?
complex and stimulating environments may not be helpful for children, especially those with ASD, because excess stimuli can cause their functioning to shut down
Whose finding in the factors affecting plastcity and learning suggest that [adults] improve and change best in a complex and stimulating environment?
Kolb et al., 2011
Prior to the 1980s, it was thought that neural architecture development was…
non-existent past early childhood
In childhood, it is clear that there are certain _ in neuroplasticity
sensitive periods
e.g., Kuhl and speech perception, pimprinting, etc.
Neuroplastic changes occurring passively during childhood is associated with _ working memory
procedural working memory
In adulthood, plasticity occurs…
albeit at a smaller scale
In adulthood, usually plasticity occurs as a result of
strong stimuli, requiring the individual to work harder to get results
In adults, neuroplasticity is associated with requiring _ attention, as associated with _ working memory
conscious attention
declarative working memory
CVAs are
cardiovascular accidents
TBIs are
traumatic brain injuries
Following brain injury, increased recruitment of regions in the DAMAGED hemisphere is associated with
improved skills (more access to those regions means greater likelihood of success in regular activities)
Following brain injury, reorganization may also include the complementary tissue in the _
contralateral hemisphere (as a back-up!) e.g., hemispherectomy often show neuroplasticity in remaining hemisphere, albeit more slow
Considerable _ exists in the cortical changes across victims
variability!
Variability of cortical changes in brain injured victims is associated with:
the number of individuals who recruit only affected hemisphere compared to those who recruit the contralateral
hemisphere as well
and…
the extent of regions that are recruited
A great example of reorganization in the complementary tissues in the contralateral hemisphere is when Broca’s area (left) is damaged [associated with rapid-fire processing], the complementary tissues in the right hemisphere associated with _ can pick up the pace, albeit with _
intonation
slower-processing
e.g., less automatic tasks can be done, such as differentiating [p] and [b], requiring more CONSCIOUS attention
The video we watched in class regarding kids with _ show that some improve with a total left hemispherectomy, which unfortunately shows _ in the right-side, resulting in little to no expression, but relatively high comprehension, much like a _ aphasic individual
epilepsy
paralysis in right side if hemispherectomy on the left
high comprehension but low expression is associated with Broca’s aphasia, and is what would be visible in these kids following the procedure
It has been repeatedly found that there is not always a direct relationship between brain damage and the _
clinical/behavioural presentation
Two possibilities for why a direct relationship doesn’t always occur with TBI and behavioural presentation:
1) cognitive reserve:
- neural reserve i.e., brain networks were active and flexible pre-injury
- neural compensation i.e., utilisation of other circuits not usually used to taking on new functions
and. ..
brain reserve capacity - physical attributes such as brain size, number of synpases
Brain networks present pre-injury refer to neural…
reserve
Utilisation of other circuits not usually used to taking on new functions post-injury refer to neural…
compensationi
What is likely for the two possibilities for why a direct relationship doesn’t always occur with TBI and behavioural presentation?
they work together
Those with higher IQ, greater educational attainment, reading skills, occupational attainment, etc. are more likely to _
do better with a similar brain insult/injury compared to those with lower levels on these measures
Early intervention and _ are the most effective rehabilitation strategies, even past “critical periods”
intense training
Neuroplasticity still is in effect _, but usually requires conscious effort and more work, therefore requiring support for intervention
into advanced age
New therapies emerging for brain insult rehabilitation include: neurotropic factors (BDNF), rTMS, electrical stimulation, and
neuroprotectants
Some evidence suggests that intervening _ results in poorer outcomes
too early or too intensively post-injury
rtMS is
repetitive transcranial magnetic stimulation
In the film “Discovering the human brain: New pathways to neuroscience, with Susan Bookheimer”, she presents the research that takes place at
the Brain Mapping Center, UCLA
What process requires the use of all four lobes?
reading
Susan Bookheimer suggests that there are _ neurons in the adult body
100 billion neurons
The three types of brain-imaging techniques include:
electromagnetic, stimulation, and
haemodynamic
Stimulation techniques are basically
a mix of electromagnetic and haemodynamic techniques
EEG/ERPs and MEG are examples of _ techniques
electromagnetic
MRI, fMRI, PET, DTI, and NIRS are examples of _ techniques
haemodynamic
rTMS is an example of _ techniques
stimulation brain-imaging techniques
Language is often focused on using _, and how different populations’ results change compared to circumstances
ERPs
_ measures water molecules and how they line up by noting the connectivity of axons and seeing where different pathways exist
diffusion-tensor imaging
_ connections, including primary auditory or visual areas can easily be shown as hyper-connected and indicative of extreme sensitivity, based on
diffusion-tensor imaging
_ are magnetic pulses that can show CAUSAL relationships by suppressing or adding stimulation to areas to see how an individual responds
repetitive transcranial magnetic stimulation
Progression of studies in brain imaging:
information was initially found from
autopsies (Broca’s area, Wernicke’s area, etc.)
the _ of the mid 20th century captured EEGs
electron microscope
In the 1960s, these studies in brain imaging began:
EEG, ERP, and MEG studies
In the 1990s, these studies in brain imaging began:
PET
fMRI emerged and predominanted in brain imaging from
1997 to 2001
Important improvements in spatial definition of language areas occurred in
2002 to 2006
Greater emphasis on using imaging data to test cognitive/psycholinguistic models of language occured in
2007 to the present
N100 denotes a _ that is created 100 _ after an auditory or visual stimulus, as measured with a _ machine
waveform
msec
EEG
M100 is specific to
magnetoencephalography (MEG)
PET is not commonly used due to the need for
ingesting positron glucose (carcinogenic?)
The neuroimaging techniques best for measuring time are
EEGs and MEGs
The neuroimaging techniques best for measuring location are:
fMRI, PET, NIRS, and DTI
Electromagnetic techniques are best for _-based research, whereas haemodynamic techniques are best for _-based research
time-based/electromagnetic
location-based/haemodynamic
The electroencephalogram is referred to as
EEG
EEG measure _ from neuronal firing, i.e. direct measure of neuronal activity
voltage changes from neuronal firing
In EEGs, signals are _ and _ compared to a reference point
averaged and filtered
ERPs are known as
event-related potentials
ERPs are associated with
language processing
Several components related to language have been identified from the _ nerve and into the _ cortex
auditory nerve, and auditory cortex
Latencies and _ of EEG waves are informative
amplitudes
Latencies in EEGs are
time gone by since stimuli was presented
e.g., N100 approximtaedly 100 msec in normal people
If a N100 occurs in normal-hearing people, would those with hearing issues be different?
yes, certainly longer
Amplitudes in EEG note the
distance from peak if wave form to base
Amplitude refers to the strength, or _ of a waveform
robustness
N400 is helpfull for determining
processing vocabulary
P600 indicates a wave form is _ to baseline
positive, whereas N600 would be negative (not aware if N600 is an actual measure)
P600 is associated with
processing GRAMMAR
Magnetoencephalography is the _ equivalent to EEG
magnetic
MEG measures direct information from _ and _ neural activity
evoked and spontaneous
MEG offer good _ and _ resolution
temporal and spatial
MEG is _-/invasive
non-invasive
MEG is _ available, and very _
not usually avaialble; very expensive
MEGs are _ in volume
quiet
Language-related ERPs:
One that is present at birth, absent in some dyslexic individuals, and is a categorical perception is
MMN or mismatch negativity
Language-related ERPs:
this is associated with native language sounds
MMN (present at birth)
Language-related ERPs:
this ERP is found at 300 msec/N300
PMN or phonological mapping negativity
Language-related ERPs:
this ERP is associated with prosodic processing/phrasing, developed very early, and may help identify syntact phrase boundaries
CPS or closure positive shift
CPS or closure positive shift is associated with
segmentation
PMN or phonological mapping negativity is associated with
acknowledging different speech sounds
MMN or mismatch negativity is associated with
deciphering native speech sounds
The order of ERPs in language development are:
- MMN
- CPS
- N400
- ?
ELAN - P600
MMN is associated with discriminating phonemes, which typically occurs at
2 months old
CPS is associated with discrimination of word stress patterns and BEFORE identification of intonational boundaries, at approximately
7 months old (or just over 0.5 years old)
N400 is associated with lexical processing (both form and semantics), and predates sentence processing, at approximately
18 months old (or 1.5 years old)
ELAN-P600 is associated with sentence processing, by understanding selectional restriction of verbs, and coinciding with local phrase structure building and understanding morphosyntactic processes by age
32 to 36 months (or 3 years old)
_ involves intravenous radioactive markers for measuring glucose metabolism
PET/positron emission tomography
PETs are quiet/loud?
quiet
PETs are invasive?
somewhat - ingesting radioactive marker
PETs are expensive?
yep
PETs are more widely available?
not really
PET are better than fMRI for researching some aspects of language, especially _ and connected speech
spoken language
_ detects levels of oxygen in response to neural activity
fMRI - functional magnetic resonance imaging
What effect is measured in fMRI?
BOLD - “blood oxygen level dependent effect”
_ can probe areas deep in the brain
fMRI
fMRI is quiet/loud?
loud
fMRI restricts movement?
yes
What is very commonly used on neurolinguistic research, with new modifications improving on limitations?
fMRI
What is better for _: fMRI or PET?
volume of machine
PET - more quiet
What is better for _: fMRI or PET?
temporal resolution
fMRI
What is better for _: fMRI or PET?
spatial resolution
fMRI
What is better for _: fMRI or PET?
invasiveness
fMRI - no need for exposure to radiation
What is better for _: fMRI or PET?
sensitivity to artifacts when subjects are speaking
fMRI
What is better for _: fMRI or PET?
research relating to auditory comprehension and speech production, especially past the single word level
PET
Structural MRI is referred to as
diffusion tensor imaging (DTI)
_ tracks diffusion of water molecules in the brain, showing white matter tracts/fibres
diffusion tensor imaging
DTI tracks diffucion of water molecules in the brain, showing _ matter tracts/fibres
white
DTI is non-/invasive?
noninvasive
DTI are quiet/loud?
loud
DTI require movement restrictions?
yes
DTI provides good
spatial data
_ may misidentify tracts both positively and negatively
DTI!
_ is an INdirect measure of neuronal activity, by using reflective light measures to measure changes in oxygen levels in hemoglobin
near infrared spectography (NIRS)
_ is low in cost, has relatively low sensitivity to head movement, and is such is very useful for young children and babies
Near infrared spectrography (NIRS)
_ products, NOT detects, brain activity
repetitive transcranial magnetic stimulation rTMS
_ applies magnetic fields through the scalp, creating a “virtual” lesion, which can demonstrate causality
rTMS
rTMS are non-invasive?
noninvasive, enabling repetitive assessment on same subject
_ is the study of the cellular composition of the central nervous system’s tissues under the microscope
cytoarchitecture
Cytoarchitecture of the cerebrum is the study of the _ composition of the _NS’ tissues under a microscope:
cellular
central nervous system
Many different kinds of neurons are found in the cerebral cortex, including: _ cells, basket cells, granular cells, and interneurons
pyramidal
Different arrangements/features are shown of _ and axons in the cytoarchitecture of cerebrum
dendrites
The size and shape of neurons or their distribution in a given area likely has _ significance
functional
Much of the cytoarchitecture of cerebrum has been learned from postmortem brains (referred to as _ research), but increasingly _ is playing a role
histological
neural imaging
_ studied the microstructure of the cerebral cortex in 1909, developing a map of more than _ areas that are still used in imaging studies today
Brodmann
40
The cellular structure of specific cerebral cortex areas is known as
cytoarchitecture
Identifying _ is critical in cytoarchitecture as cellular structural differences result in different kinds of neuronal function
identifying borders between areas in cortical cellular structures
Hagoort suggests that Broca’s area should be referred to as
Broca’s complex
Historically, Brocas area = Brodmann area(s):
44 and 45
Brodmann areas 44 (pars opercularis) and 45 (pars triangularis) refer to
Broca’s area
Brodmann’s area 44 is associated with
dysfluent speech; articulatory problems
Brodmann’s area 45 is associated with
language problems
Implications for brain imaging studies:
does Broca’s area include just BA44 and 45, or also BA_ and BA_?
47 and 6
Implications for brain imaging studies:
Recent research with high level cytoarchitectonic information from histological studies paired with well-designed functioning imaging studies is providing what?
more complete understanding of complex underlying functions of more deeply defined regions