QUIZ 7- Circuitry Flashcards
Common types of neuronal circuits
simple
complex
divergent
convergent
rhythm
parallel after discharge
simple
two axons signaling in one direction
complex
two axons signaling in a circuit
unpredictable
whole is greater than sum of parts
convergent
many axon synapses on one target neuron
Ex one visual neuron receives info from 1000 other cells
divergent
one axon projects to many other cells
rhythm generating
central pattern generators
minimum of two cells
create complex movement
Circuit formation
axon is guided to right target during critical period of fetal development
state function
state function
under particular conditions will something occur
right connection can only be made under right conditions
repair of spinal chord is limited by this
Axon guidance
growth cone
chemotaxis
growth cone-Filopodia
membrane projection that orientates toward appropriate chemical cue
chemotaxis
“train of breadcrumbs”
proteins and chemicals
Circuit Physiology- neuronal circuits
developed during fetal and neonatal growth
maintained by use
plasticity
wiring dictates function
complex behaviors are generated by simple circuits
Brain operational Design
functionally specialized with hemispheric asymmetries
neurons generate ion fluxes across cell mem in a standard way
hard tasks take up more brain volume/neurons
brain modifies spinal chord activities
brain function is highly plastic
Structural Imaging of Brain
magnetic resonance imaging
diffusor tension imaging
functional imaging of brain
functional MRI
electroencephalography
sMRI
translates local differences in water content to outline shape
examines shape NOT function
injuries, stroke, tumor
Diffusor tension imaging
detection of how water travels along axonal projections in brain
info about neuron interconnectivity
Functional MRI
measures small changes in blood flow associated with different brain activities
electroencephalogram (EEG)
measures brain electrical activity with scalp electrodes
epilepsy, sleep disorders
Phineas Gage
iron rode through frontal lobe
caused:
personality change
loss of self-restraint
alteration in reason and ability to understand instruction
change in socialization
Human brain mapping
longitudinal fissures divides left and right
lateral fissures divides top and bottom
Anatomical brain regions
cerebrum
brainstem
cerebellum
diencephalon
Cerebrum
largest in term of volume
cerebral cortex=outer layer
neocortex= largest part of cortex
higher level of processing, cognition
brainstem
autonomic and reflex centers
cerebellum
“little brain”
movement and coordination
Diencephalon
centers for homeostatic control fo a wide range of physiologies
Cerebral Cortex Physiology
contralateral control
frontal lobe
parietal lobe
occipital lobe
temporal lobe
frontal lobe
motor speech
memory formation
personality
emotion
parietal lobe
sensory and integration
collection of info from multiple
proprioception
management of taste, sight, touch, and smell
somatosensory cortex
occipital lobe
visual processing
visual memories
visual association area
temporal lobe
hearing, speech, language, smell
organization and language comprehension
memory formation and retrieval
Wernickes Area- speech comprehension
3 parts of frontal cortex
prefrontal
motor
brocas area
Primary motor cortex
functional-volume of area is indictive and anatomical stratification- neurons controlling ring finger near neurons of middle and little finger
homunculus
representation of motorneurons controlling muscles in different regions of body
Betz cells
striated muscle control of neurons
Sensory Cortex
sensory input- thermal, touch, proprioception, pain
inputs from the contralateral chord and thalamus
integration- sensory and motor signals for skilled movement
wernickes area
speech comprehension
Wernickes aphasia
inability to understand words and communicate
Brocas area
vital role in generation of articulate speech
Primary Language area
Broca’s
Wernicke’s
angular gyrus
arcuate fasciculus
angular gyrus
superior edge of temporal lobe
arcuate fasciculus
axonal tracts that connect Brocas and Wernickes
allows for coordinated and comprehensible speech
aphasia
inability to comprehend or formulate language
visual association area
interprets information acquires through primary visual cortex
cerebral dominance
left- language, math reasoning, logical reasoning
right- spatial abilities, face recognition, visual imagery, music
mechanism of Brain lateralization
minute temporal delays in other hemisphere neuronal cells
key trait of CNS
interconnections made by neurons
white matter
myelin coated axonal projections
projection
connections between subcortical regions, telencephalon, and diencephelon
