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175 Cards in this Set
- Front
- Back
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What are cutaneous and subcutaneous mechanoreceptors?
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1. Meissner's corpuscles
2. Merkel disk receptors 3. Pacinian corpuscles 4. Ruffini endings 5. Hair-lylotrich, hair-guard 6. Hair down 7. Field |
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What are thermal receptors?
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Cool, warm receptors and heat and cold nociceptors
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What are nociceptors?
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1. mechanical
2. thermal-mechanical (2) 3. polymodal |
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What are muscle and skeletal mechanoreceptors?
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1. muscle spindle primary
2. muscle spindle secondary 3. golgi tendon organ 4. joint capsule mechanoreceptors 5. stretch-sensitive free endings ** see chart in notes |
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What is relationship between receptive field size and adaptation for Meissner's corpuscles, Pacinian corpuscles, Merkel's disk and Ruffini's ending?
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1. Meissner's= small field, fast adaption
2. Pacinian= large field, fast adaption 3. Merkel's= small field, slow adaption 4. Ruffini's= large field, slow adaption |
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What are various sizes of primary afferent axons?
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From small(unmylienated) to large (most mylienated)
1. C-skin, group IV-muscle (pain, temp., itch) 2. A gamma-skin, group III-muscle (pain and temp.) 3. A beta-skin, group II-muscle (mechanoreceptors of skin) 4. A alpha-skin, group I-muscle (proprio. of skeletal muscle) |
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What is the dorsal spinocerebellar tract?
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Central axons of dorsal root ganglia
-peripheral axonal receptors detect proprioception (conscious and unconscious) from lower extremities |
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What is the ventral spinocerebellar tract?
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Central axons of dorsal root ganglia
--peripheral axonal receptors detect unconscious proprioception from lower extremities |
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What is the medial lemniscus?
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Nucleus gracilius, cuneatus, and Z extend internal arcurate fibers that cross great sensory decussation
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What are the tracts of PandT?
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spinothalamic tracts
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What is pain?
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1. nociceptors are receptors that respons to noxious stimuli resulting from skin/soft tissue injury
2. nociceptor activation causes (usually) pain 3. pain is subjective interpretation of unpleasant stimulus 4. not necessarily product of nociceptor excitation 5. also nociceptors respond to tickeling, itching and temperature |
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What is nociceptive pain?
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1. pain resulting form nociceptor activation due to tissue injury and resultant inflammation
2. examples=sprains, fractures, burns, bumps, bruises, inflammation, obstructions, and myofascial pain |
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What is neuropathic pain?
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1. resulting from direct insult to nerve
2. examples=post shingles, neuralgia, reflex sympathetic dystrophy / causalgia (nerve trauma), components of cancer pain, phantom limb pain, carpal tunnel syndrome, and peripheral neuropathy (widespread nerve damage) |
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What are the two different types of pain?
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1. fast-sharp prickeling pain
2. slow-dull pain |
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What is shock?
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Both types of pain cause this, the indagenous opiates and adrenaline don't have time to suppress pain inhibition
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What is different about pain from visceral areas?
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It enters spinal cord same way as somatic pain which can explain why feels like something else-referred visceral pain.
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What is primary hyperalgesia?
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1.Refers to sensitization of surronding nociceptors after injury or inflammation
2. drugs like ibprofen, aspirin work against this |
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What is central hyperalgesia?
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1. refers to sensitization of dorsal horn cells after injury
2. due to persistant activation of NMDA receptors by glutamate releasing C fibers 3. alterations can result in long term decrease of pain threshold of patient 4. where chronic pain comes from, have to break the pain cycle but not reinjure oneself |
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What is the 1st step in pain pathway summary?
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1. central axons of A-delta and C fibers ascend 2 segments in dorsolateral fasciculus of Lissauer before synapsing w/dorsal horn
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What is the purpose of the reticular formation, periqueductal gray, nuclues gracilis and cuneatus, and hypothalamus in pain pathway?
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Lateral spinothalamic tract sends collaterals to these places on way to thalamus (and then to sensory cortex)
-periqueductal gray is involved in emotional reactions to pain -hypothalamus involved in autonomic control of pain -nucleus gracilis, cuneatus responsible for sensory pain and temp. info -reticular formation is point of crossing over of tracts |
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What is the gate control theory of pain (control of pain in spinal cord)?
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Observation that proprioceptive and mechanical stimulation diminishes perception of pain
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What is the opiate system (control of pain in the brain)?
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Stimulation of periaqueductal gray results in profound and specific analgesia (can feel touch and vibration but not pain)
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What are enkephalins, beta-endorphins, dynorphins?
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1. endogenous opoid peptides
2. released in various areas of nervous system 3. u, B, k opiate receptors have been id'ed and also occur in various areas of nervous system 4. accounts for different symptoms of opiate use (not pain control related) |
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What is the diencephalon?
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1. middle part of cerebrum
2. thalamus 3. hypothalamus 4. subthalamus (not seen in lab) 5. epithalamus 6. tremendous amount of functions |
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What is the thalamus?
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1. Collection of nuclei (gray matter)and associated laminae
2. lies in floor of central portion of lateral ventricles 3. forms superior part of lateral wall of 3rd ventricle 4. 70% population has interthalamic adhension, transverses 3rd ventricle and don't know much about it |
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What are the functions of the thalamus?
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1. receives info about sensation, vision and hearing
2. mediates motor info from cerebellum and basal ganglia (when to start/stop) to motor cortex (how to do it) 3. involved in autonomic maintenance of consciousness |
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What are the nuclear groups of the thalamus?
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1. anterior
2. medial 3. ventrolateral (laterl/ventral nuclei, pulvinar, medial/lateral geniculate bodies) 4. reticular (not formation) 5. intralaminar 6. midline |
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What are the divisions of the thalamus?
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1. ventral anterior
2. ventrolateral 3. ventral posterior 4. anterior 5. medial 6. lateral dorsal 7. lateral posterior 8. posterior |
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What is the anterior nucleus of thalamus?
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Forms anterior tubercle which is posterior to boundary of interventricular foramen of Monro
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What is Korsakoff's psychosis (syndrome)?
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1. metabolic disturbance caused by chronic severe alcoholism
2. causes lesions around 3rd ventricle (esp. medial, anterior thalamic nuclei, mammillary bodies, connections between them) 3. get short term memory loss w/patient attempt to compensate by confabulating |
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What is confabulating?
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inserting remote past memories into fluent but blatantly untrue stories
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What is the medial group of nuclei of thalamus?
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1. receives info from basal ganglion, amygdala, midbrain, some spinothalamic fibers (emotional response to pain-anger and fear)
2. functions in memory and behaviour |
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What is the ventral anterior and ventral lateral thalamus?
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receives info from basal ganglia and dentate nucleus (cerebellum)
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What is the ventral posterior nucleus of thalamus?
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all sensation except olfaction reaches consciousness here, integrated and sent to sensory cortex
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What is the medial geniculate body of the thalamus?
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Receives info from inferior brachium and due to this from inferior colliculus
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What does the medial geniculate body project to and what pathway is it part of?
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1. projects to auditory cortex by auditory radiation
2. part of auditory pathway |
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What does a lesion of the medial geniculate body cause?
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Dimished hearing more pronounced contralaterally
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What is the lateral geniculate body of thalamus?
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Receives info from optic tract
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What does the lateral geniculate body project to and what pathway is it part of?
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1. projects to visual cortex by optic radiation
2. part of visual pathway |
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What does a lesion to the lateral geniculate body cause?
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Visual loss (contralateral homonymous hemianopsia=partial blindness resulting in a loss of vision in the same visual field of both eyes)
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What is the lateral dorsal nucleus of the thalamus?
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1. reciprocal connections w/limbic system areas
2. functions as emotional expression |
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What is the lateral posterior nucleus of thalamus?
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1. reciprocal connections w/sensory association of cortex of parietal lobe
2. functions as integration of sensory info |
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What is pulvinar of thalamus?
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1. receives fibers from retina and superior colliculus
2. projects into parietal, occipital and temporal lobes 3. visual reflexes and eye movements |
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What is reticular nucleus of thalamus?
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1. reciprocal connections w/thalamus and cortex
2. does modulation of thalamic activity |
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What is intralaminar nuclei of thalamus?
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1. centromedian nucleus
-part of limbic system -maintains consciousness and alertness -integrates emotional responses to pain |
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What is midline nuclei of thalamus?
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1. form interthalamic adhensions
2. 70% of population have this, unsure of function |
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Where does the dorsal spinocerebellar tract enter/begin and 1st synapse?
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Enters dorsal horn and synapse w/nucleus dorsalis=clarke's column
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What does the dorsal spinocerebellar tract actually begin and where does it ascend to?
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1. nucleus dorsalis rises to dorsal spinocerebellar tract
2. tract ascends to medulla w/o crossing |
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What happens to the dorsal spinocerebellar tract in the medulla?
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1. in medulla conscious spinocerebellar fibers synapse w/nuclues Z
2. in medulla unconsciencous spinocerebellar fibers enter cerebellum by inferior cerebellar peduncle |
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Where does the ventral spinocerebellar tract begin/enter and where does it 1st synapse?
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Enters dorsal horn and synapses with nucleus proprius
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Where does the ventral spinocerebellar tract actually begin and where does the tract ascend?
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1. nucleus proprius rises to contralateral(1ST CROSSING) ventral spinocerebellar tract
2. tract ascends to midbrain |
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Where does the ventral spinocerebellar tract end and through what?
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Enters cerebellum by superior cerebellar peduncles after CROSSES 2ND TIME
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What does the nuclei gracilias, cuneatus, Z form when fibers cross GSD?
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Forms contralateral medial lemniscus
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How is the medial lemniscus somatically arranged?
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1. somatotopically organized so in medulla cervical to sacral fiber arranged from dorsal to ventral
2. Pons and midbrain cervical to sacral fibers arranged medial to laterally |
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Where does the medial lemniscus end and where do the fibers end?
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Ends in thalamus and from there fibers end in sensory cortex
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What is fast sharp prickeling pain?
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Transmitted to spinal cord by myelinated A-delta fibers that carry thermal and mechanical noxious stimuli
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What is slow dull pain?
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Transmitted to spinal cord by unmylinated C fibers that carry high intensity thermal, chemical, mechanical noxious stimuli
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What does primary hyperalgesia result in the release of and what does this do?
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1. results in release of bradykinin, prostaglandins, histamine, acetylcholine, substance P, CGRP etc. from different cell populations in injury
2. inflammation agents decrease the nociceptors activation threshold |
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What is 2nd step of pain pathway?
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2. central axons synapse in dorsal horn
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What is 3rd step of pain pathway?
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3. primary afferents synapse w/nucleus proprius, pericornual cells and substantia gelatinosa
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What is 4th step of pain pathway?
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4. most synapses involve interneurons that control pain perception but axons of nucleus proprius cross midline and form lateral spinothalamic tract
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What is 5th step of pain pathway?
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5. spinothalamic tract ascends to thalamus in anterolateral system
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What is 6th step of pain pathway?
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6. lateral spinothalamic tract sends collaterals to reticular formation, periaqueductal gray, nucleus gracilis, cuneatus, hypothalamus when going to thalamus
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What is 7th step of pain pathway?
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7. spinothalamic fibers synapse on thalamus and fibers ascend to sensory cortex where they end
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What do A-beta mechanoreceptors do in gate control of pain?
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Send collaterals to substantia gelatinos which inhibit nucleus proprious (feel less pain)
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What do A-delta and C nociceptors do in gate control of pain?
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Send excitatory signals to nucleus proprious and inhibits substantia gelantinosa (causes pain)
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Summary of mechanoreceptors and nociceptors?
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-mechanoreceptors turn off pain
-nociceptors turn on pain -relative excitation of pathways can modulate pain (TENS units based on this) |
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What does the stimulation of periaqueductal gray cause in opiate system?
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1. blocks withdraw reflexes in response to painful stimuli
2. can excite serotoninergic raphe nuclei and noradrenergic locus coeruleus |
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What do the serotoninergic raphe nuclei and noradrengergic locus coeruleus do in opiate system?
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1. Both send fibers travel in fasciculus of Lissauer to inhibit output of pericornual cells and nucleus proprious
2. descending inhibitory pathways interfere w/glutamate secretion of primary pain afferents |
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What does opioid administration do?
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-in gray results in anesthesia (like electrical stimulation)
-natural pain suppressors, acts like dental shot, feel something but no pain -use of morphine and codine as pain relievers show discovery of opiate receptors and endogenous opioids |
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What is the relationship between opiate system and enkephalins, B-endorphins, dynorphins (endogenous opioid peptides)?
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-there are different symptoms of opiate use that is not related to pain control
-accounted for by receptors for different types of opioid peptides and their receptors in different parts of nervous system |
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What is part of the thalamus forms the roof of the 3rd ventricle?
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Ependymal lining of 3rd ventricle reflected from one side to other along stria medullaris thalami
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What is the lateral surface of the thalamus called?
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Lateral surface covered by thin sheet of fibers called External Medullary Lamina
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What is the thalamus divided by internally?
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Vertical sheet of white matter called Internal Medullary Lamina
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What info does the anterior nucleus receive and by what tract?
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Limbic system info from mammillary bodies by mamillothalamic tract
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What does the anterior nucleus project to?
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Projects to cingulate gyrus (concentration)and frontal cortex
-ADD patients will function better w/caffeine in comparison with someone without it |
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What is the function of anterior nucleus?
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Memory and emotions
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In what other patients/conditions do you see Korsakoff's psychosis (syndrome)?
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1. Also see this with patients with severe B1 deficiency (absorption disorders)
2. kills liver and area around 3rd ventricle 3. load with thiamine to fix |
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Where does the medial group of nuclei in thalamus project to?
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-prefrontal lobe (where uniqueness, character and habits are)
-lesion here results in change of character |
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What does ablation of medial group of nuclei of thalamus cause?
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ablation (complete removal) results in symptoms that parallel Korsakoff's syndrome
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Where does the VA and VL of thalamus project to?
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projects to motor and premotor cortices
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What is the VA and VL of thalamus functions and what does stimulation cause?
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1. Functions in motor integration and maintenance of consciousness
2. Stimulation causes increase in Parkinsonian rigidity and tremor |
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What does ablation of VA and VL of thalamus cause?
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ablation relieves some Parkinson symptoms
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What is the ventral posterior medial nucleus of thalamus?
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all sensory info from head/face reaches consciousness and integrated (1st point)
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What is ventral posterior lateral nucleus of thalamus?
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all sensory info from body reaches consciousness and integrated
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What does a lesion of the ventral posterior nuclei of thalamus cause?
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lesion here leads to anesthesia (contra. loss sensation) or thalamic syndromes (hypersensitivity)
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What is the hypothalamus?
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Forms inferior part of lateral wall and floor of 3rd ventricle (includes mammillary bodies and tuber cinereum etc.)
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What is the hypothalamus divided into?
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1. anterior
2. intermediate 3. posterior -all have number of nuclei within zones |
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What systems is the hypothalamus part of?
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1. limbic
2. controls autonomic responses 3. endocrine |
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What are the hormonal hypothalamus functions?
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1. endocrine control: releases inhibiting factors that promote production and secretion of hormones by anterior pituitary
2. neurosecretion by hypothalamohypophysial tract of oxytocin by paraventricular nucleus 3. Neurosecretion of Antidiuretic hormone (ADH) by supraoptic nucleus (lesion=diabetes insipidus=polydipsia, polyuria) |
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What are the hormones of the hypothalamus responsible for?
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1. Oxytocin=breast feeding and contractions
2. ADH=absorption of water to body from urine secretions |
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How do the hormones travel in pituitary gland (major gland of endocrine)?
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down axon by exoplasmic flow to posterior pituitary then to anterior pituitary then blood
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What is diabetes insipidus?
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tasteless urine, not glucose related diabetes
-increase in water intake and output -no absorption |
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What is diabetes meladius?
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honey tasting urine, glucose related, type I and II diabetes
-increase in glucose levels -causes increase thrist -therefore increase urination as drink lots |
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What is an automonic function of hypothalamus?
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1. general autonomic effects
2. different regions mediate sympathetic or parasympathetic activity |
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What is temperature regulation function of hypothalamus?
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1. anterior responds to increase in T by causing cutaneous vasodilation and sweating
2. posterior responds to decreases in T by cutaneous vasoconstriction and shivering |
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What is BP and osmolarity control function of hypothalamus?
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1. by regulating food and water intake
2. contains glucose sensitive satiety centre (lesion=hyperphagia) 3. contains hunger/thirst center (lesion=hypophagia) |
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What is sexual/reproduction function of hypothalamus?
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1. controls gametogenesis
2. controls cyclic variations 3. controls maturation and maintenance of 2nd sex characteristics by controlling gonadotrophin production of anterior pituitary |
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What is biological clock function of hypothalamus?
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1. suprachiasmatic nucleus involved in circadian rhythms
2. affects fluctuation in body T in 24 hours |
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What is emotional function of hypothalamus?
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1. emotion, fear, rage, aversion, pleasure, reward
2. hypothalamus and limbic system and prefrontal cortex match feelings to app. emotional expression (abuse in childhood=inapp. assignment of emotion) |
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What is the subthalamus?
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1. transition zone between midbrain and thalamus
2. has subthalamic nucleus=functional part of basal ganglia 3. lesion=hemiballismus (uncontrollable, violent torsonal mov't) |
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What is epithalamus?
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1. habenula+stria medullaris+pineal gland+posterior commissure+habenular commissure
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What is function of habenula?
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olfactory reflexes (limbic system)
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What is function of stria medullaris?
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connects septal area to habenula
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What is function of posterior commissure?
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connects 2 superior colliculi and functions in visual reflexes
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What is function of pineal gland?
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1. secretes antigonadotropin (inhibits gonadotropin of anterior pituitary)
2. secretes melatonin (involved in circadian rhythms) |
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What happens with growth/destruction of pineal gland?
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1. growth=delayed puberty
2. destruction=precocious puberty |
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What is the relationship between tasting and smelling?
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1. 70% of taste is smell
2. 70% of smell input is bad |
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What is the cerebral cortex?
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1. frontal lobe
2. temporal lobe 3. parietal lobe 4. occipital lobe |
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What separates the frontal and parietal lobes?
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central sulcus
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What is each lobe separated into?
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1. subdivided in gyri (gyrus)
2. divided by fissures called sulci (sulcus) |
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What are the properties of the cerebral hemispheres?
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1. control/receive info from contralateral body
2. 2 spheres are not functionally identical 3. connected by corpus callosum |
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What are Broadmann's areas?
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52 cortical divisions pertaining the different histological layouts
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What is the frontal lobe?
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1. consists of superior, middle, inferior frontal gyri
2. precentral gyrus on lateral surface 3. gyrus rectus and orbital gyri on inferior |
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What does the precentral gyrus do in frontal lobe?
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(area 4=motor homunculus)
-primary motor cortex 2. mediates motion of joint along vector |
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What is homunculus?
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representation of cortical areas dedicated to processing info from particular part of body
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What is the premotor and supplementary motor cortex of precentral gyrus?
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1. area anterior to precentral gyrus
2. associated with motor programming and preparation |
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What is the prefrontal cortex functions?
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-motor integration and planning, judgement
-dominant hemisphere=language production |
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What does a lesion to Broca's area cause?
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Broca's area=posterior portion of inferior frontal gyrus
Lesion=aphasia (expressive) by non-fluent speech, impaired repitition, mostly preserved language comprehension |
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What is the temporal lobe?
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1. superior + middle + inferior temporal gyri on lateral
2. parahippocampal gyrus 3. medial and lateral occipitotemporal gyri on inferior |
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What is transverse temporal gyri of Heschl?
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1. primary auditory cortex
2. deep into lateral fissure is insula=auditory integration and taste |
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What are occipitotemporal gyri functions and lesion?
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1. visual association areas
2. perception of contrast color and shape 3. lesion=agnosia (can't ID) |
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What is the parahippocampal gyrus function?
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1. along with underline hippocampal formation and amygdala = limbic system concerned with vital functions
2. such as feeding, reproduction, emotion, memory |
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What is the parietal lobe?
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1. precuneus on medial surface
2. postcentral gyrus, superior, inferior parietal lobules on lateral 3. inferior lobule = supramarginal and angular gyri |
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What is the postcentral gyrus function?
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1. primary somatosensory cortex (area 3,1,2)or sensory homounculus
2. area posterior to it is sensory association area |
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What are the posterior parietal association areas functions?
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1. superior and inferior lobules
2. receive visual, auditory, limbic inputs due to 3-D perception |
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What does a lesion of posterior parietal association areas cause?
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1. results in agnosias=inability to recognize 3-D objects through touch
2. personal neglect syndrome=ignoring left side one's body 3. spatial neglect syndrome=ignoring left visual field |
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What is wernicke's area?
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1. posterior portion of sueprior temporal gyrus
2. adjoining supramarginal and angular gyrus (inferior lobule) 3. on dominant hemisphere concerned with language comprehension |
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What does a lesion to wernicke's area cause?
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1. wernicke's aphasia (receptiveness)
2. fluent speech w/impaired repetition and comprehension |
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What is the occipital lobe?
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1. cuenus and lingual gyri
2. contains primary and association visual cortices (areas 17,18,19) 3. lesion=anopsia (defect in visual field) |
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What is the premotor and supplementary motor cortex of precentral gyrus?
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1. area anterior to precentral gyrus
2. associated with motor programming and preparation |
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What is the prefrontal cortex functions?
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-motor integration and planning, judgement
-dominant hemisphere=language production |
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What does a lesion to Broca's area cause?
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Broca's area=posterior portion of inferior frontal gyrus
Lesion=aphasia (expressive) by non-fluent speech, impaired repitition, mostly preserved language comprehension |
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What is the temporal lobe?
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1. superior + middle + inferior temporal gyri on lateral
2. parahippocampal gyrus 3. medial and lateral occipitotemporal gyri on inferior |
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What is transverse temporal gyri of Heschl?
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1. primary auditory cortex
2. deep into lateral fissure is insula=auditory integration and taste |
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What are occipitotemporal gyri functions and lesion?
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1. visual association areas
2. perception of contrast color and shape 3. lesion=agnosia (can't ID) |
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What is the parahippocampal gyrus function?
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1. along with underline hippocampal formation and amygdala = limbic system concerned with vital functions
2. such as feeding, reproduction, emotion, memory |
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What is the parietal lobe?
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1. precuneus on medial surface
2. postcentral gyrus, superior, inferior parietal lobules on lateral 3. inferior lobule = supramarginal and angular gyri |
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What is the postcentral gyrus function?
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1. primary somatosensory cortex (area 3,1,2)or sensory homounculus
2. area posterior to it is sensory association area |
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What are the posterior parietal association areas functions?
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1. superior and inferior lobules
2. receive visual, auditory, limbic inputs due to 3-D perception |
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What does a lesion of posterior parietal association areas cause?
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1. results in agnosias=inability to recognize 3-D objects through touch
2. personal neglect syndrome=ignoring left side one's body 3. spatial neglect syndrome=ignoring left visual field |
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What is wernicke's area?
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1. posterior portion of sueprior temporal gyrus
2. adjoining supramarginal and angular gyrus (inferior lobule) 3. on dominant hemisphere concerned with language comprehension |
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What does a lesion to wernicke's area cause?
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1. wernicke's aphasia (receptiveness)
2. fluent speech w/impaired repetition and comprehension |
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What is the occipital lobe?
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1. cuenus and lingual gyri
2. contains primary and association visual cortices (areas 17,18,19) 3. lesion=anopsia (defect in visual field) |
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What are the motor and sensory homunculus?
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Motor=precentral gyrus in frontal lobe
Sensory=postcentral gyrus in parietal lobe |
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What is the ANS?
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1. largely involuntary system
2. composed parasympathetic, sympathetic, enteric systems |
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What is the anatomical organization of ANS?
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1. pregang. fibers w/cell bodies in nucleus in CNS
2. postgang. fibers w/cell bodies in ganglion outside CNS |
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What is the ratio in sympathetic system of pre/post ganglionic fibers?
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1:10
more widespread |
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What is ratio of parasympathetic system of pre/post ganglionic fibers?
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1:3
more pinpoint |
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What is special about autonomic fibers of ANS?
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1. fibers and targets don't hold pre/postsynaptic specializations
2. so NT's can go for long distances before target hit |
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What do the pregang. autonomic termianls release?
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Ach mediated by nicotinic Ach receptors
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What do the postgang. sympathetic terminals release?
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norepinephrine (noradrenaline) mediated by 5 types noradrenergic receptors (a1, a2, B1, B2, B3), found in diff. target sites w/diff. functions
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What is the function of the pre/post ganglionic terminals?
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Release # NT's that function directly on target tissue or have modulatory role
(neuropeptide Y, substance P, neurtensin, somatostatin, enkephalins) |
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What do postgang. parasympathetic terminals release?
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release Ach mediated by 3 types muscurinic receptors (M1, M2, M3) found in diff. target sites and have diff. functions
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What do the sympathetic (peripheral BV and nerves)and parasympathetic systems innervate?
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1. cardiac muscles
2. smooth muscles (BV) 3. glandular tissues 4. mediate # visceral reflexes |
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What is the enteric division of ANS?
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1. greater autonomy
2. mediates digestive reflexes |
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What is the sympathetic nervous system of ANS?
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1. pregang. sympathetic cells in intermediolateral gray of T1-L2
-T1:T5=same level synapses and synapses w/ganglion above -T5:L2=same level synapses and synapses w/ganglion below |
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What is the path of the sympathetic pregang. fibers?
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1. exit through ventral root
2. join briefly with spinal nerve and ventral rami 3. form white rami communicantes and enter paravertebral sympathetic ganglia (sympathetic trunk) |
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What are the postgang. sympathetic fibers? (sympatetic supply of body wall and limbs)
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1. form gray rami communicantes
2. enter spinal nerves 3. postgang. from cervical, thoracic, lumbar ganglia reach target by spinal nerves 4. innervate peripheral BV, sweat glands, arrectores pilorum muscles (goosebumps) |
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Waht is the sympathetic supply of head and thoracic viscera?
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1. postgang. sym. fibers from cervical ganglia by cranial nerves or plexi innervate CRANIAL BV, sweat glands, hair follicles, galnds, organs of head/thorax
2. lesion of superior cervical ganglion (RF of medulla)=Horner's syndrome |
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What is Horner's syndrome?
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1. lesion of superior cervical ganglion or RF in medulla
2. causes ptosis (droopy lid), meiosis (pinpoint pupil), anhidrosis (no sweat one side face), enophthalmos (sunk eyeball) |
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What is pregang. sympathetic supply of abdominal/pelvic viscera?
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1. pregang. sympathetics fibers go to ganglia w/o synapsing
2. forms splanchnic nerves 3. these synpase w/prevertebral ganglia |
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What is the postgang. sympathetic supply of abdominal/pelvic viscera?
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1. fibers from prevertebral ganglia innervate GI tract, pancreas, kidney, liver, bladder, genitalia
2. some splanchnic nerve fibers bypass prevert. ganglia 3. innervate adrenal medulla=releases epinephrine/norepinephrine to circulation (STRESS) |
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What is parasympathetic nervous system of ANS?
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pregang. parasym. cels in CN 3, 7, 9, 10 and in intermediolateral gray of S2-4
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What are pregang. cells in brainstem of parasym. nervous system of ANS?
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1. Edinger-Westphal nucleus (3)
2. superior salivatory nucleus (7) 3. inferior salivatory nucleus (9) 4. dorsal motor nucleus (10) |
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What is the synapse path for CN 3?
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oculomotor nerve synapses w/ciliary ganglion innervates sphincter pupillae and ciliary muscles
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What is synapse path for CN 7?
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facial nerve synapses in pterygopalatine which innervates lacrimal gland and serous/mucous glands of nasopharynx AS WELL AS submandibular ganglion innervates submandibular/sublingual salivary glands
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What is the synpase path for CN 9?
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glossopharyngeal nerve synapses w/otic ganglion innervates parotid salivary gland
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What is synapse path for CN 10?
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vagus synapses w/diffuse throacic and abdominal ganglia innervates heart, oesophagus, lungs, stomach, liver, gall bladder, pancreas, foregut/midgut derivatives
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What does the intermediolateral column S2-4 innervate?
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1. rises to give pregang. parasym. fibers
2. through pelvic splanchnic nerves innervates descending and sigmoid colon, pelvic viscera |
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What is the enteric nervous system of ANS?
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controls GI tract, pancreas, gall bladder function
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What do the motor/sensory neurons do?
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1. motor=innervate Smooth muscle, vasculature and secretion of gut
2. sensory=respons to gut wall tension and changes in chemicals in gut |
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What are the sensory components of the ANS and its higher controls?
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1. facial nerve=conveys visceral chemosensory info on taste
2. glossopharyngeal conveys info on head and neck viscera 3. vagus conveys info from abdominal/thoracic viscera |
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What happens to all of the info coming from the sensory components?
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1. converge at solitary nucleus and reacts in 3 ways
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What are the 3 ways the solitary nucleus reacts?
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1. direct control autonomic function by set of reflexes (projects to 10 and spinal cord nuclei)
2. projects to RF and periaqueductal gray which reg. breath, BP, HR 3. projects to hypothalamus--goes to thalamus, amygdala and cingulate cortex where hypothalamus exerts its functions by controlling brainstem and spinal cord nuclei through its functions |
