Neuro Reticular Nuclei

Front 1

Raphe nuclei
function

Back 1

serotinergic input to brain and spinal cord, modulation of sensory input, consciousness - have ascending and descending fibers

Front 2

Raphe nuclei - nuclei raphus magnus
location, afferents, efferents , function

Back 2

in medulla and caudal pons .
sensory afferents from spinal cord, dorsal column nuclei, trigeminal nuclei and periaqueductal grey

Efferents - to brain, spinal cord( somatic sensory pathways)
affect motor and sensory fxn

Front 3

Central Nuclear group
function

Back 3

origin of reticulospinal tracts, some eye movement nuclei, reticular arousal system

Front 4

raphe medullary nuclei ( raphus magnus) - relation to pain sense

Back 4

Have fibers that project to dorsal horn through dorsal lateral funiculus. - projections down are bilateral, correspond with opiate containing neurons (enkephalin) - stimulation produces analgesia w/ no effect on tactile sense because A - sense fibers not effected

Front 5

how does raphus magnus influence the autonomic system

Back 5

projects via the dorsal longitudinal fasciculus to the dorsal motor nucleus of the vagus, nucleus of the solitary tract, and the spinal trigeminal nucleus and preganglionic autonomic neurons
- adds serotonin influence to autonomic functions

Front 6

effect of stimulation of the periaqueductal region on raphe magnus analgesia actions

Back 6

stimulation of the periaqueductal region can produce a long lasting inhibition of pain
- internuncial neurons in periaqueduct - have enkephalin ( neurotransmitter) - binds to opiate receptors

Front 7

what inhibits stimulation of the periaqueductal region

Back 7

hypothalamus

Front 8

does raphe nuclie have any motor functions

Back 8

raphe nuclei affect motor activity -
serotonergic effects

Front 9

rostral raphe nuclei afferents

Back 9

afferents are from prefrontal cortex, hippocampus, hypothalamus, interpeduncular nucleus and the ventral tegmental area (dopamine influences) - ventral tegmental area is pain, pleasure sense

Front 10

rostral raphe nuclei - where do ascending tracts go ,what are the effects

Back 10

send ascending fibers via the median forebrain bundle to hypothalamus and wide regions of cortex, thalamus, subthalamus, neostriatum, and limbic areas.

Their effects on cortical neurons can be excitatory or inhibitory. May affect diverse physiological processes such as sleep, aggressive behavior, and neuroendocrine functions

ssri works through this pathway

Front 11

central nuclear group - motor nuclei
afferents
efferents
action

Back 11

afferents - motor cortex, premotor area, cerebellum (particularly vestibulocerebellum, fastigial nucleus), superior colliculus and spinal cord.

efferents - give off axons which descend to form the reticulospinal tracts
- output to spinal cord

fxn - extensor excitatory, - effect basic fxns of posture , some effect eye movements

Front 12

path of pontine ( medial) reticulospinal tract

function

where does input to the tract come from

Back 12

sent by central nuclear motor nucei -
descend primarily ipsilaterally via the medial ventral funiculus to terminate in spinal gray.

powerful excitatory - to spinal motor neurons(extensor biased), - axial and proximal limb muscles

receives input from cerebellum

Front 13

Medullary reticulospinal tract (aka lateral reticulospinal tract)-
path, functions

Back 13

neurons in central nuclear group -
descends bilaterally to spinal cord by lateral and ventrolateral funiculus

fxn - inhibitory influence (extensor biased) over spinal motor neurons and spinal reflex activity
causes sleep atonia ( paralysis of muscles during sleep)

receives excitatory inputs from cerebral cortex, and upper pontine subcoeruleus nucleus.

Front 14

PPRF
function

Back 14

PPRF Paramedian pontine reticular formation ( member of central reticular nuclei group) - lies near abducens

function - coodinates horizontal and vertical eye movements through MLF with CN III and the pretectal area.
Accessory oculomotor

Front 15

organization of central nuclei group

Back 15

medial nuclei are motor

lateral nuclei are sensory

Front 16

central nuclear group - sensory nuclei
functions
where do projections go
afferents

Back 16

afferents - many sensory sources - spinoreticular, spinothalamic, and trigeminothalamic, superior colliculus (visual system), olfaction, auditory and gustatory

project rostrally via the central tegmental tract to broadly projecting nuclei of the thalamus, - intralaminar nuclei

action - desynchronize eeg waves - Brings about behavioral arousal / maintenance of consciousness ( helps keep you awake)

participate in ARAS system - keep you conscious

Front 17

Nuclei of the Lateral Parvocellular zone

function
afferents
efferents

Back 17

fxn - sensory information for local motor processing
- acts as a chewing, swallowing center
- generates feeding behaviors - finding food, ect

afferents from spinal cord, spinal trigeminal complex, auditory system and cerebral cortex (particularly from face area of motor cortex).

efferents to hypoglossal, facial motor nuclei, trigeminal motor nuclei , nucleus ambiguus ( fibers from cn 9,10,11)

also sends some efferents to thalamus

Front 18

Lateral Parvocellular zone - parabrachial complex
function, afferents, efferents

clinical importance

Back 18

fxn - respiratory related nuclei
afferents from solitary nucleus, insular cortex, and adjoining parietal lobe

efferents to - hypothalamus, preoptic area, intralaminar thalamic nuclei and amygdala

- a relay for ascending visceral information
-pontine portion of parabrachial complex - important clinically in regulating respiratory rhythm

Front 19

parabrachial complex - superficial medullary groups
location

function
efferents

Back 19

Superficial Medullary Neuronal Groups- located in medullary area of CN VIII and IX near the inferior olive

fxn - to coordinate cardiovascular and respiratory sensory reflex responses and regulation based on chemoreceptors

send some efferents project to hypothalamus and preganglionic autonomic neurons of the medulla and spinal cord.

superficial medullary also provides sensory input for cardiovascular activity (e.g. O2, CO2, pH).

Front 20

dorsal respiratory neuronal group (DRN)

location
function
afferents
efferents

Back 20

lateral region of the solitary nucleus at this level ( medulla near cn VIII and IX) forms the dorsal respiratory neuronal group (DRN)

fxn - integrates respiratory related sensory information

afferent - from the superficial medullary area, carotid (primary) and aortic bodies, direct and indirect afferents from spinal cord (stretch receptors) and the vagus

efferents - contralateral to phrenic nuclei

Front 21

ventral respiratory group ( of parabrachial reticular nuclei)

location
function
afferents
efferents from rostral, caudal portions of these nuclei

Back 21

location - extend from C1 to the caudal pons.

rostral group of nuclei from the obex to the caudal pons - excitatory to phrenic and throacolumbar inspiratory motor neurons (through DRN group)

caudal portion (C1 to the obex) are excitatory to thoracolumbar expiratory motor neurons.

Front 22

function and location of botzinger complex

Back 22

Bötzinger complex of nuclei - located At the most rostral end of the ventral respiratory group .

fxn - inhibits premotor (interneurons) and motor respiratory neurons during their silent periods of the respiratory cycle/ pattern generator for resp cycle

Front 23

Kölliker-Fuse nucleus of the parabrachial nuclear complex


function

Back 23

pneumotaxic center - a primary regulator of respiratory rhythm although it does not generate the rhythm.

Front 24

cardiovascular responses in reticular formation - medial solitary nucleus

Back 24

medial solitary nucleus at the level of IX and X receives stretch receptors from the carotid sinus. Stimulation (simulating high blood pressure) gives input to the vagal motor nucleus which reduces heart rate.

Front 25

how is peripheral vasodilation accomplished via the reticular formations

Back 25

neurons in the central nuclear group contribute to projections to the intermediolateral column in the spinal cord to produce peripheral vasodilation ( autonomic)

Front 26

effect of catecholaminergic reticular groups

Back 26

contain primarily norepinephrine, but also epinephrine, and dopamine
- provide a pathway for pharma agents to affect catecholamines

- can effect blood pressure

Front 27

locus coeruleus

what group does it belong to ?

where is it located

where do its projections go

Back 27

location - dorsolateral portion of rostral pontine tegmentum and extends into the midbrain

locus coeruleus - catecholaminergic nucleus

projects - rostrally via central tegmental tract and medial forebrain bundle , supplies much of the broad catecholamine projections to the forebrain

fxn - plays an important role in the facilitation of motor activity and is involved in sleep mechanisms.

Front 28

what role do caudally projecting colinergic reticular nuclei play

Back 28

Caudally projecting neurons have projections to cardiovascular and respiratory areas, autonomic nuclei of the brainstem and the intermediolateral cell column of the spinal cord. They appear to participate in the muscular atonia in sleep

Front 29

what nuclei are included in the cholinergic group

Back 29

The cholinergic nuclei of the brainstem include the motor nuclei of the cranial nerves, but also rostrally and caudally projecting nuclei in the reticular formation.

Front 30

pedunculopontine nucleus

afferents

efferents

function

Back 30

is a cholinergic reticular nucleus

It receives input from the basal ganglia and possibly cortex

sends projections back to the basal ganglia and the central nuclear groups.

fxn - The pedunculopontine nuclei appear to generate locomotor patterns ( ex - walking patterns)

Front 31

area postrema

Back 31

area postrema (chemical trigger zone, area for emesis) is located in the 4th ventricle near the vagal triangle. It has no blood brain barrier. It forms the afferent limb of the vomiting reflex and is sensitive to emetic drugs. ( apomorphine and digoxin)


receives afferents from solitary nucleus, spinal cord

projects back to solitary nucleus and some motor cranial nerve nuclei (e.g. Nucleus ambiguous), forming the afferent limb of the vomiting reflex