General Principles Flashcards
Computerized tomography[CT]
intersecting x-rays to identify bonesandblood vessels, fluid
Magnetic resonance imaging [MRI]
magnetic field andradio frequency to identify structure of greymatter, GMV; white matter, WMV; ventricles
Diffusion MRI or diffusion tensor imaging [DTI]
track where water molecules go by altering field gradients – fiber tracking by statistical averaging
EEG is good at what and bad at what
excellent temporal & poor spatial resolution;complex signal detection
fMRI
hemodynamic imaging, blood oxygen level dependent response; spatial pattern brain areas working
measure changes in blood oxygenation due tochanges in cerebral blood flow (fMRI).
fMRI functional connectivity
task-based working connections (effective connectivity
Motor learning induced what in the brain
greater neural efficiency in task-related neural
Learning requires less brain activity
why do we use imaging techniques
Neuron communication/use of transmitter requires energy (oxygen/glucose) whichrequiresblood flow.
Neuroimaging techniquesmeasure rates of cerebral blood flow (PET) or can measure changes in blood oxygenation due tochanges in cerebral blood flow (fMRI).
PET
Neuroimaging techniquesmeasure rates of cerebral blood flow (PET)
Integration ofmultiple imaging methods can provide what
can result in a more comprehensive view of brain processes.
Central Nervous System
Cerebral hemispheres
Diencephalon
Midbrain
Pons and cerebellum
Medulla oblongata
Spinal cord
Peripheral Nervous System
Cranial nerves, spinal nerves and support cells outside of the CNS
projection neurons do what kind talk
long distance talk
receptor or center to a target
interneurons do what kind of talk
short distance talk
neuron to nearby neuron
Supportive Cells
Schwann [PNS] & glial [CNS] cells
Schwann [PNS] & glial [CNS] cells function
feed, nurture, and protect; remove excess neurotransmitters; and some may ‘talk.’
neurons always live in
groups
what are neuron groups called in the central nervous system
nuclei
what are neuron groups called in the PNS
ganglia
serial processing v. parallel processing
Serial processing – limits the possibility of recovery, take one out the entire system is done for
Spatial summation
several weak signals from different locations are converted into a single larger one
Temporal summation
converts a rapid series of weak pulses from a single source into one large signal
distributive control
diversity in behavior: more than one means of responding
talk’ and feedback enable distributive control of behavior and learning
Peripheral feedback
Sensory receptors
Moving generates sensation
(Re-afference)
Knowledge of feedback
Central feedback
motor copy or efferent copy
Central brain will predict how that move will put you in space – if it predicts that this is a mis-move it will correct
Feedforward adjustments
Heterarchical control is enabled by
Peripheral and central feedback
Heterarchical control
distributed across many centers ; interconnected, not top-down flow
what occurs in the process of learning
alterations in activity of neurons or neuron pools: experience can change behavior; changes in current state and novel information can both influence the neuron’s response
central pattern generator[CPG] neurons
Rhythmic, alternating, stereotypic butnot obligatory pattern (can change)
neuronal circuits that when activated can produce rhythmic motor patterns such as walking, breathing, flying, and swimming in the absence of sensory or descending inputs that carry specific timing information.
Critical periods
developmentaltime periods in which events havetheir greatest effect on determinationof characteristics of a part of the NS
genie - language
is development predictable
yes
NS disease or injury disrupts theorder and predictability
Divergence in neurons
one connected to many diffuse influence
Feed forward inhibition
Activate the agonist and turn off antagonist
reciprocal inhibition
Feedback inhibition
Extend the arm – there is a mech to turn this off, allows for flexibility in the next move
- if we want to keep our arm out we just keep on sending signals
recurrent inhibition
MR specctrophy frunction
looking at the chemical composition of tissues
EEg funtion
temporal pattern of activity
MEG
magnetic measurment of energy superimposed on the brain
fMRI is good at what
spatial pattern of the brian
