Section 3 Notes Flashcards
Type of information carried by the Dorsal Column/Medial Lemniscal System?
epicritic somatosensory information (touch, pressure, joint position sense, vibration sense)
Gracile fasciulus carries information from the ____
middle thoracic and lower limbs (epicritic in DML and proprioceptive in D. Spinocerebellar)
The cuneate fascilus is not present below the ____ spinal cord
mid throacic
____funciulus carries dorsal or posteriro column axons
dorsal
Type of info carried by the anterolateral system?
PROTOPATHIC - opposite side: pain and temp, touch, pressre
Anterolateral System carries information from the ____ side of the body
opposite
the ANTEROLATERAL system is made up of ___ ____ and ____ axons
spinoreticular, spinotectal, and spinothalamic
What system carries touch and pressure ipsilaterally?
dorsal column system
What system carries touch and pressure contralaterally?
anterolateral cell column (this is less discrete than dorsal column system)
dissociated sensory loss is a symptom of dmaage to the ____
spinal cord pain and temp is on one side, fien touch, vibration, and joint position on another
the ____ system regulates movement and does not normally contribute to our conscious perception of limb position
spinocerebellar
the Spinocerebellar system carries ____ information
proprioceptive from muscles and joints (to coordinate muscle activity during movement)
The dorsal spinocerebellar tract icarries proprioceptive information from the ____
lower half of the body
proprioceptive info. from lower limbs acends in the ____ before synapsing in Clarkes n.
gracile fascilus
____ synapses in Clarke’s nucleus
proprioceptive info. from lower half of the body
the dorsal spinocerebellar tract carries proprioceptive info on the ____ side of the body
same
dorsal spinocerbellar tracts terminates in the ____
inferior cerebellar peduncle
cuneocerebellar tract terminates in the _____
inferior cerebellar peduncle
what is carried by the cuneate fasciulus?
from the lower half of the body:
- epicritic (DML)
- proprioceptive (dorsal spinocerebellar)
from the cuneate fascilus, synapse in the ___ nucleus
accessory cuneate
ventral spinocerebellar tract arises from neurons in the____
intermediate gray
the ____ spinocerebellar tract crosses in the anterior white commissure
ventral, *BUT THEY RECROSS
the ventral spinocerebellar tract terminates in the
superior cerebellar peduncle
the spino olivary axons carry ___ information
proprioceptive
the spinoolivary axons terminate in the
inferior olivary n.
the pyramidal tract arises from the
cerebral cortex
the pyramidal tract splits at the ____
caudal most medulla
Corticospinal axons originating from neurons in the motor cortex terminate particularly in the more _____ portions of the intermediate gray,
lateral
The axons of the pyramidal tract that cross cross at the ____
pyramidal decussation (they then form the lateral corticospinal tract)
Corticospinal axons from sensory cortex terminate in the ______ and modulate sensory input.
dorsal horn
Pyramidal tract that does not cross
anterior corticospinal tract
the lateral corticospinal tract concerned particularly with____ and ____
discrete individual digit movements and distal motor control.
The ventral corticospinal tract is more concerned with ___ and ____
axial and proximal muscular movement
brainstem spinal tracts involved in distal muscle control
rubrospinal
The pathways involved in proximal motor control run more medially or ventrally in the spinal cord ?
medially
origin of rubrospinal
red nucelus
origin of vestibulospinal
vestibular n.
origin of reticulospinal
retiuclar formation
from the ___ system enters the spinal cord as large diameter dorsal root axons
dorsal coilumn/medial lemniscus
Direct Descending tracts (have direct contact to cortex)
Corticospinal Tract (Spinal cord motor neurons) Corticobulbar Tract (Brainstem cranial nerve nuclei) Corticopontine Tract (Cerebellum) Cortico-rubro-olivary Tract (Cerebellum)
Indirect Descending tracts (extrapyramidal)
Tectospinal Tract Reticulospinal Tract Vestibulospinal Tract Rubrospinal Tract
UMN signs
Hyperreflexia Hypertonia Positive Babinski
LMN signs
Hyporeflexia Hypotonia Negative Babinski Muscle Atrophy Fasciculations
acensding tract that brings proprioceptive ifno from turnk and limbs
spinocerebellar
cuneate fasciulus
carries epicritc from DML and dorsal spinocerebellar
The motor cortex projects to the ___ pathways
- direct pyramidal 2. indirect – brainstem pathways (also projects to the basal ganglia)
how does the basal ganglia controls both the direct and indirect pathways?
via projections of the GP to the VA and VL in the thalamus and then back to the mtoor and premotor cortex
if lesion of the spunal cord, which side is it on?
same side unless pain and temp loss
brainstem X, it will be on the same side as the ___ sx
most rostral since the most rostal sx will cause damage to the cranial nerve nucleus
brainstem X, it will be on the opposite side as the ___ sx
descending sx
if forebrain X the sx will be
opposite the lesion
if cerebellum X the pathology will be on the ___ side
same
in what state is msucles noramlly?
they are never totally relaxed (this is normal tone)
muscle tone is maintained by what factors
1.sensry neuons form msucle spindle 2. corticospinal and inidrect pathways (maintain baseline excitcity)
When the resting contraction of the muscle is less than normal, the tone is called ____
“hypotonic”
axons from the ___ of each retina cross
nasal (temporal visual field)
the optic tract wraps around the
thalamus and the crus cerebri
pathways of optic tracts
- to lgn in thalamus
- in the brahcium of the superior colliclus to terminate on the pretectal area
- superior colliculus
Axons carrying information about the upper half of the visual field pass ____ and terminate in the ____
pass deep to the cortex of the temporal lobe and terminate in the calcarine sulcus
carrying information about the lower half of the visual field pass deep to the ____ lobe
parietal
axons carrying information about the lower half of the visual terminate in the cortex forming the
superior bank of the calcarine sulcus or the cuneaus gyrus
the _____ this pathway governs long-term reactions to light, e.g., resetting daily biological rhythms, detecting seasonal changes in light.
Hypothalamus
the pretectal nuclei are interconnected via the____
posterior commissure
he pretectal nucleus functions like a ____
light meter
It receives bilateral input from the two eyes and it contains cells that calculate the total light energy entering the eye.
Edinger-Westphal nucleus is the ___ component of IIII nucleus
parasympathetic
function of pregnaglionic EQ axons
project with CN IIII to contrisct pupil
CN 8 terminates in ____
the dorsal and ventral cochlear n.
the dorsal and ventral cochlear n. lie in the
inferior cerebellar peducnle
second order neurons arise in the cochlear nuclei, and project to several nuclei,
and to both sides of the brain crossing mainly in the
trapezoid body in the caudal PONS
projections of cochlear nulcie are
- superior olive
- other nuclei like nuclei of trapezoid body, nucleus of lateral lameniscus etc
Much of the lateral lemniscus terminates in the
inferior colliculus.
No matter what ncueli the cochlear n. project to, all ifnromation ends up in the
lateral leniscus
The inferior colliculus in turn projects to the ___
MGN by the inferior bracium of the inferior colliculus
MGN projects auditory ifnromation to
heschls gyrus
earliest level of bilateral miing of information from the two years
second order neurons (after the cochlear ncueli)
the left Heschl’s gyrus receives projections from the right Heschl’s gyrus through the
corpus callosum
