Physiology: Chapter 9

Front 1

link interneurons to peripheral receptors and effectors.

Back 1

Sensory (afferent) and efferent neurons

Front 2

Gray Matter

Back 2

consists of unmyelinated nerve cell bodies, dendrites, and axon terminals.
->Clusters of cell bodies in brain and spinal chord =nuclei

Front 3

White matter

Back 3

contains very few cell bodies and mostly myelinated axons.
-> bundles of axons connecting regions = tracts

Front 4

Bone and connective tissue support of the CNS

Back 4

-Bone: skull -> brain , vertebral column -> spinal chord
-Connective tissue: meninges:
-> 1. dura matter - thickest layer, contains sinuses
-> 2. arachnoid matter - loosely tied to inner membrane , creates subarachnoid space
-> 3. pia matter - thin membrane appears to surface of brain and spinal chord. Associated with arteries for brain blood supply.
ECF - cushions neural tissue -> cerebrospinal fluid and interstitial fluid.
cerebrospinal fluid -> ventricles
interstitial fluid -> lies inside the pia matter
both communicate through pial membrane

Front 5

Cerebrospinal Fluid (CSF)

Back 5

salty solution continuously secreted by the choroid plexus.
-> provides physical protection (padding and buoyancy).
-> chemical protection -> closely regulated extracellular environment

Front 6

blood brain barrier

Back 6

-highly selective permeability of brain capillaries
->via endothelial tight cell junctions

Front 7

areas in brain that are leaky just like normal capillaries (not functional blood brain barrier)

Back 7

hypothalamus -> hypothalmic-hypophyseal portal system
medulla oblongata vomiting center

Front 8

what molecules does the brain desperately need? (run on)

Back 8

-oxygen -> passes freely across blood brain barrier
-glucose -> memb. trans. move glucose move glucose from plasma to interstitial fluid.
->15% of blood for brain.

Front 9

spinal chord roots

Back 9

dorsal root -> carry incoming sensory information -> cell bodies in dorsal root ganglia
ventral root -> carries info from CNS to muscles and glands.

Front 10

where sensory fibers from dorsal roots synapse with interneurons

Back 10

dorsal horns
-> two nuclei: one for somatic, one for autonomic

Front 11

contains cell bodies of motor neurons that carry efferent signals to muscles and glands.

Back 11

ventral horns
->organized into somatic motor and autonomic nuclei
->efferent fibers leave the spinal cord via the ventral root

Front 12

Ascending tracts

Back 12

white matter columns in spinal cord that take sensory information to the brain.
-occupy dorsal and external lateral portions of spinal chord.

Front 13

Descending tracts

Back 13

white matter columns in spinal cord that take mostly efferent (motor) signals from the brain to the cord.
-occupy ventral and interior lateral portions of the white matter.

Front 14

propriospinal tracts

Back 14

tracts that remain in the spinal chord

Front 15

spinal reflexes

Back 15

-spine can work as an integrating center
->sensory neuron -> through grey matter -> to efferent neuron
->spinal interneurons may route sensory info to brain through ascending tracts or or bring commands from brain to motor neurons.
interneurons may modify info that passes through them

Front 16

Functions associated with cerebral cortex

Back 16

sensory -> perception
motor -> skeletal muscle movement
association areas -> integration of information and direction of voluntary movement

Front 17

functions of cerebellum

Back 17

-movement coordination

Front 18

functions of diencephalon

Back 18

thalamus - integrating center and relay station for sensory and motor information
pineal gland - melatonin secretion
hypothalamus - homeostasis, behavioral drives
pituitary - hormone secretion

Front 19

functions of brain stem

Back 19

midbrain - eye movement
pons - relay station between cerebrum and cerebellum, coordination and breathing
medulla oblongata - control of involuntary functions
-> cranial nerves 2-12 branch off of brain stem

Front 20

*reticular formation

Back 20

diffuse collection of neurons that extends throughout brainstem.
-sleep/arousal
-muscle tone
-breathing
-pain

Front 21

*medulla oblongata

Back 21

-transition from spinal chord to brain proper (below pons)
-white matter includes ascending somatosensory tracts (sensory info to brain) and descending corticospinal tracts that convey info from cerebrum to spinal chord
gray matter has a lot of the involuntary functions
->pyramids crossover for opposite side control
-blood pressure
-breathing
-swallowing
-vomiting

Front 22

corpus callosum

Back 22

connects the two cerebral hemispheres

Front 23

cerebral gray matter regions (3)

Back 23

cerebral cortex
basal ganglia
limbic system

Front 24

cerebral cortex

Back 24

outer layer of cerebrum
-distinct vertebral columns and horizontal layers
-higher brain function

Front 25

basal ganglia

Back 25

control of movement (basal nuclei)

Front 26

limbic system

Back 26

-link between higher cognitive functions and emotional responses
-contains amygdala, cingulate gyrus (both contain emotion and memory), hippocampus (learning and memory)

Front 27

hypoglycemia

Back 27

low blood glucose

Front 28

cerebral lateralization

Back 28

each lobe of the cerebrum has specialized functions that are not symmetrical with corresponding other lobe

Front 29

lobe functional areas

Back 29

frontal - motor
parietal - sensory
occipital - vision/visual
temporal - auditory
(inside) -> gustatory (superior to ->) olfactory (technically temporal)
[all have smaller cortex that is surrounded by an association area]

Front 30

functional association is not concrete, a person can learn to write with the other hand because of ____ of neural connections

Back 30

plasticity

Front 31

primary somatic sensory cortex

Back 31

in parietal lobe of brain
-termination point of pathways from skin, musculoskeletal, and viscera.
[touch,temp,pain,itch,and body position]
damage here affects opposite side of body

Front 32

habituation

Back 32

a decreased response to an irrelevant stimulus that is repeated over and over.

Front 33

motor output

Back 33

-part of efferent division of nervous system
-3:
->skeletal muscle movement
->neuroendocrine signals - release of hormones from hypothalamus and adrenal medulla
->visceral responses - smooth/cardiac muscle or endocrine/exocrine glands

Front 34

sleep

Back 34

-easily reversible state characterized by lack of interaction with external environment