Sensory and Motor Pathways Flashcards
Posterior Funiculus-Medial Lamniscal Pathway
Conducts sensory information through brainstem, through diencephelon, terminating in cerebral cortex
has tracts in spinal cord and brainstem
conducts information about limb arrangements (proprioception), discriminative touch, pressure, and vibration
Anterolateral Pathway
spinothalamics
located in the anterior and lateral funiculi of the spinal cord
axons projecting from primary neurons enter the spinal cord and synapse on secondary neurons within the posterior horn
relay information about crude touch, pressure, as well as pain and temperature
axons of the secondary neurons cross and relay stimulus information to the opposite side of the spinal cord before ascending toward the brain
Spinocerebellar Pathway
consists of anterior/posterior tracts
proprioception regarding posture, balance, coordination of skilled movements
DO NOT USE TERTIARY NEURONS
only use primary and secondary neurons
primary, secondary and tertiary neurons in sensory relaying
primary has cell body in spinal root ganglia or sensory ganglia of cranial nerves
secondary is an interneuron that delivers signal to the thalamus. cell body is located in the posterior horn of the spinal cord or a brainstem nucleus
tertiary is also an interneuron inside the thalamus
% of signals that actually reach the cerebral cortex
1%, 99% is filtered out
Diencephalon
Contains the epithalamus, hypothalamus, and the thalamus
Diencephalon 2: what we care about for the first exam
thalamus
Thalamus: posterior group
a. lateral geniculate nuclei: relay visual information from optic tract to visual cortext and midbrain
b. medial geniculate nuclei: relays auditory information from inner ear to auditory cortex
c. pulvinar nuclei: integrate and relay sensory information for projection to association areas of cerebral cortex
