Divisions of the nervous system Flashcards
What distinguishes brain structures
kinds of neurons, way neurons are arranged, way axons are distributed
Afferent
sensory messages carried in superior portion of spinal cord, dorsal horns
Efferent
motor messages in inferior portions, ventral horns
Segments and groups of spinal cord
31 segments, 5 groups: cervical, thoracic, lumbar, sacral, coccygeal
Damage at cervical level causes
quadriplegia/tetraplegia - loss of sensory and voluntary motor functioning in arms and legs
Damage at thoracic level causes
paraplegia loss of sensory and voluntary function in legs
Autonomic nervous system components
parasympathetic and sympathetic nervous system
Peripheral nervous system components
somatic and autonomic
Hindbrain
pons, medulla, cerebellum
Midbrain
superior and inferior colliculi, sustantia nigra, reticular formation/RAS
Forebrain
subcortical and cerebral cortex
Subcortical structures
thalamus, hypothalamus, basal ganglia, amygdala, hippocampus
Cerebral cortex
frontal lobes, parietal lobes, temporal lobes, occipital lobes
Brain and spinal cord covered by three layers (meninges)
dura mater, arachnoid, pia mater
CSF fills what
subarachnoid space (between arachnoid and pia mater), central canal of spinal cord and four cerebral ventricles
Hydrocephalus cause
obstruction of flow of CSF, leads to build-up of fluid and enlargement of ventricles
Peripheral nervous system consists of
12 cranial nerves and 31 sensory and motor nerves (spinal)
somatic nervous system carries info from where to where
from sense receptors to CNS and from CNS to skeletal muscles
autonomic nervous system
sensory nerves from viscera to CNS and motor nerves from CNS to smooth muscles, cardiac muscle and glands
Sympathetic
arousal and expenditure of energy
Parasympathetic
conservation of energy, rest and relaxation
Stages of brain development
proliferation, migration, differentiation, myelination, synaptogenesis
proliferation
new cells produced in neural tube - 2 1/2 week old
migration
immature neurons migrate to final destination 8 weeks
differentiation
neurons develop axons and dendrites
myelination
glial cells form an insulating sheath around the cell’s axon – occurs postnatally
synaptogenesis
formation of synapses, mostly occurs postnatally, influenced by endogenous and exogenous factors
Apoptosis
cell death
CT scan useful for
diagnosing pathological conditions such as tumors, blood clots, MS
MRI better than CT b/c
not xray, better resolution, more detail, not just on horizontal plane - 3D
What provide info on brain activity
SPECT and PET
PET scan good for
assess cerebrovascular disease, Alzheimer’s disease/dementia, schizophrenia
