Pokorski Notes Test 4 Part 2

Front 1

two important functions of spinal cord and spinal nerves

Back 1

pathways for sensory and motor impulses and responsible for reflexes

Front 2

spinal cord structure

Back 2

42-45cm; roughly cylindrical - slightly flattened on ea. side; 2 longitudinal depressions - posterior and anterior median fissure; cord is shorter than the vertebral canal

Front 3

regions of the spinal cord

Back 3

cervical, thoracic, lumbar, sacral, coccygeal

Front 4

conus medullaris

Back 4

tapering inferior end of the spinal cord; marks the official end of the spinal cord proper

Front 5

cauda equina

Back 5

inferior to conus medullaris, nerve roots that project inferiorly from the spinal cord

Front 6

filum terminale

Back 6

with the cauda equina; thin strand of pia mater that helps anchor the conus medularis to the coccyx

Front 7

spinal nerves

Back 7

31 pairs assoc w/spinal cord that connect the CNS to muscles, receptors and glands; each side has 8C, 12T, 5L, 5S, 1Co

Front 8

gray matter location/distribution in spinal cord

Back 8

centrally located, letter H or a butterfly; anterior horns, lateral horns, posterior horns; gray commissure

Front 9

white matter location/distribution in spinal cord

Back 9

external to gray matter; 3 regions: posterior funiculus -

Front 10

dermatome

Back 10

specific segment of skin supplied by a single spinal nerve; all spinal nerves but C1 innervate a segment of skin - assoc w/ a dermatome

Front 11

intercostal nerves

Back 11

anterior rami of T1-T11; travel in the intercostal space sandwiched b/w two adjacent ribs

Front 12

nerve plexuses

Back 12

network of interweaving anterior rami of spinal nerves; split into multiple named nerves that innervate the body; cervical plexuses, brachial plexuses, lumbar plexuses, sacral plexuses

Front 13

cervical plexus

Back 13

anterior rami of C1-C4; innervates skin an muscles of neck area

Front 14

brachial plexus

Back 14

C5-T1; innervates upper limb

Front 15

reflexes

Back 15

rapid, automatic, involuntary rxns of muscles or glands to a stimulus

Front 16

properties of reflexes

Back 16

stimulus req'd; rapid response requires that few neurons be involved and synaptic delay be minimal; automatic response occurs the same way every time

Front 17

components of a reflex arc

Back 17

the neural wiring of a single reflex
always begins at a receptor in PNS
communicates w/CNS
ends at a peripheral effector cell

Front 18

ipsilateral reflex arc

Back 18

both the receptor and effector organs of the reflex are on the same side of the spinal cord

Front 19

contralateral reflex

Back 19

when the sensory impulses from a receptor organ cross over through the spinal cord to activate effector organs in the opposite limb

Front 20

monosynaptic reflex

Back 20

simplest; interneurons not involved; patellar reflex - used to assess functioning of the spinal cord

Front 21

polysynaptic reflexes

Back 21

more complex neural pathways that exhibit a number of synapses involving interneurons within the reflex arc; longer delay b/w stimulus and response

Front 22

stretch reflexes

Back 22

monosynaptic reflex that monitors and regulates skeletal muscle length; patellar reflex; when stimulus results in the stretching of a muscle that muscle reflexively contracts

Front 23

golgi tendon reflex

Back 23

prevents skeletal muscles from tensing excessively; Golgi tendon organs are nerve endings located w/in tendons near a muscle-tendon junction;

Front 24

ganglion

Back 24

cluster of neuron cell bodies within the PNS

Front 25

center

Back 25

group of CNS neuron cell bodies with a common function

Front 26

nucleus

Back 26

center that displays discrete anatomic boundaries

Front 27

nerve

Back 27

axon bundle extending through the PNS

Front 28

nerve plexus

Back 28

network of nerves

Front 29

tract

Back 29

CNS axon bundle in which the axons have similar function and share a common origin and destination

Front 30

funiculus

Back 30

group of tracts in a specific area of the spinal cord

Front 31

pathway

Back 31

centers and tracts that connect the CNS with body organs and systems

Front 32

ascending pathways

Back 32

carry sensory info from the peripheral body to the brain

Front 33

descending pathways

Back 33

transmit motor info from the brain or brainstem to muscles or glands

Front 34

somatotopy

Back 34

pathways that connect parts of the primary motor cortex to a specific body part

Front 35

All pathways are composed of _____ tracts.

Back 35

paired

Front 36

pathways are composed of how many neurons working together?

Back 36

2 or 3

Front 37

sensory pathways

Back 37

have primary, secondary and sometimes tertiary neurons that facilitate the pathway's functioning

Front 38

motor pathways

Back 38

use an upper motor neuron and lower motor neuron; cell bodies are located in the nuclei associated with each pathway

Front 39

sensory pathways conduct info about

Back 39

limb position and the sensations of touch, T, P, and pain

Front 40

somatosensory pathways process stimuli received from

Back 40

receptors within the skin, muscles and joints

Front 41

primary (first order) neurons

Back 41

first neuron in sensory pathway; dendrites are part of the receptor that detects a specific stimulus; cell body is in posterior root ganglia of spinal nerves or the sensory ganglia of cranial nerves

Front 42

secondary (second-order) neuron

Back 42

interneuron; in either posterior horn of the spinal cord or a brainstem nucleus; axon projects to the thalamus, where it synapses with the tertiary neuron

Front 43

tertiary neuron

Back 43

interneuron; cell body in thalamus; thalamus is central processing and coding center for almost all sensory information

Front 44

posterior funiculus-medial lemniscal pathway

Back 44

projects through spinal cord (PF), brainstem (ML) and diencephalon before terminating within the cerebral cortex; sensory stimuli concerned with proprioceptive info about limb position and discriminative touch, pressure, and vibration sensations

Front 45

anterolateral pathway

Back 45

located in the anterior and lateral white funiculi of the spinal cord; anterior and lateral spinothalamic tract; crude touch and pressure, pain and temp;

Front 46

spinocerebellar pathway

Back 46

conducts proprioceptive info to cerebellum for processing to coordinate body movements; composed of anterior and posterior spinocerebellar tracts; different from other sensory pathways in that they do not use tertiary neurons

Front 47

motor pathways

Back 47

descending pathways in the brain and spinal cord that control the activities of skeletal muscle; formed form cerebral nuclei, cerebellum, descending projection tracts and motor neurons

Front 48

corticobulbar tracts

Back 48

transmit motor info to control the cranial nerves; descend from the cerebral cortex through the brainstem and form a pair of thick bulges in the medulla called the pyramids

Front 49

cerebral cortex

Back 49

higher order mental functions: consciousness, learning, memory, and reasoning;

Front 50

cerebral lateralization

Back 50

each hemisphere tends to be specialized for certain tasks; higher order centers in both hemispheres tend to have different but complementary functions

Front 51

cerebral lateralization

Back 51

each hemisphere tends to be specialized for certain tasks; higher order centers in both hemispheres tend to have different but complementary functions

Front 52

left hemisphere

Back 52

categorical hemisphere; categorization and symbolization; contains Wernicke's area and the motor speech area; language; sci/math; controls speech in most ppl

Front 53

Right hemisphere

Back 53

representational hemisphere; visuospatial relationships and analyses; imagination, perception, spatial relationships, sights, sounds, smells, tastes

Front 54

hemispheres remain in contact through ______

Back 54

commissures, esp the corpus callosum, which contain a ton of axons projecting b/w the hemispheres