chapter 3 Flashcards
cerebrospinal fluid
a clear fluid similar to blood plasma that fills the ventricular system of the brain and the subarachnoid space surrounding the brain and spinal cord
neuraxis
an imaginary line drawn through the center of the length of the central nervous system from the bottom of the spinal cord to the front of the forebrain
anterior
with respect to the central nervous system, located near or toward the head
posterior
with respect to the central nervous system located near or toward the tail
rostral
“toward the beak”, with respect to the central nervous system in a direction along the neuraxis toward the front of the face
caudal
toward the tail; with respect to the central nervous system, in a direction along the neuraxis away from the front of the face
dorsal
toward the back; with respect to the central nervous system in a direction perpendicular to the neuraxis toward the top of the head or back.
ventral
toward the belly; with respect to the central nervous system in a direction perpendicular to the neuraxis toward the bottom of the skull or front surface of the body
lateral
toward the side of the body, away from the middle
medial
toward the middle of the body away from the side
ipsilateral
located on the same side of the body
contralateral
located on the opposite side of the body
cerebral cortex
the outermost layer of gray matter of the cerebral hemisphere
cross section
with respect to the central nervous system a slice taken at right angles to the neuraxis
frontal section
a slice through the brain parallel to the forehead
horizontal section
a slice through the brain parallel to the ground
sagittal section
a slice through the brain parallel to the neuraxis and perpendicular to the ground
midsagittal plane
the plane through the neuraxis perpendicular to the ground; divides the brain into two symmetrical halves
meninges
the three layers of tissue that encase the central nervous system: the dura mater, arachnoid membrane and pia mater
dura mater
the outermost of the meninges; tough and flexible
arachnoid membrane
the middle layer of the meninges, located between the outer dura mater and inner pia mater
pia mater
the layer of the meninges that clings to the surface of the brain, thin and delicate
subarachnoid space
the fluid filled space that cushions the brain; located between the arachnoid membrane and the pia mater
ventricle
one of the hollow spaces within the brain, filled with cerebrospinal fluid
lateral ventricle
one of the two ventricles located in the center of the telencephalon
third ventricle
the ventricle located in the center of he diencephalon
cerebral aqueduct
a narrow tube interconnecting the third and fourth ventricles of the brain, located in the center of the mesencephalon
fourth ventricle
the ventricle located between the cerebellum and the dorsal pons, in the center of the metencephalon
choroid plexus
the highly vascular tissue that protrudes into the ventricles and produces cerebrospinal fluid
arachnoid granulation
small projections of the arachnoid membrane through the dura mater into the superior sagittal sinus; CSF flows through them to be reabsorbed into the blood supply
forebrain
the most rostral of the three major divisions of the brain; includes the telencephalon and diencephalon
cerebral hemisphere
one of the two major portions of the forebrain, covered by the cerebral cortex
cerebrum
consists of the two cerebral hemispheres
subcortical region
the region located within the brain, beneath the cortical surface
sulci
a groove in the surface of the cerebral hemisphere smaller than a fissure
fissure
a major groove in the surface of the brain, larger than a sulcus
gyrus
a convolution of the cortex of the cerebral hemispheres separated by sulci or fissures
primary visual cortex
the region of the posterior occipital lobe whose primary input is from the visual system
calcarine fissure
a fissure located in the occipital lobe on the medial surface of the brain most of the primary visual cortex is located along its upper and lower banks
primary auditory cortex
the region of the superior temporal lobe whose primary input is from the auditory system
lateral fissure
the fissure that separates the temporal lobe from the overlying frontal and parietal lobes
primary somatosensory cortex
the region of the anterior parietal lobe whose primary input is from the somatosensory system
central sulcus
the sulcus that separates the frontal lobe from the parietal lobe
insular cortex
a sunken region of the cerebral cortex that is normally covered by the rostral superior temporal lobe and caudal inferior frontal lobe; can receive info about taste
sensory association cortex
those regions of the cerebral cortex that receive information from the regions of the primary sensory cortex
primary motor cortex
the region of the posterior frontal lobe that contains neurons that control movements of skeletal muscles
motor association cortex
the region of the frontal lobe rostral to the primary motor cortex; also known as the premotor cortex; controls behavior
prefrontal cortex
the region of the frontal lobe rostral to the motor association cortex; involved in formulating plans and strategies
corpus callosum
a large bundle of axons that interconnects corresponding regions of the association cortex on each side of the brain
limbic cortex
phylogenetically old cortex, located at the medial edge of the cerebral hemispheres; part of the limbic system
cingulate gyrus
a strip of limbic cortex lying along the lateral walls of the groove separating the cerebral hemispheres just about the corpus callosum
limbic system
a group of brain regions including the anterior thalamic nuclei, amygdala, hippocampus, limbic cortex, and parts of the hypothalamus as well as their interconnecting fiber bundles
hippocampus
a forebrain structure of the temporal lobe constituting an important part of the limbic system; big on memory
amygdala
a structure in the interior of the rostral temporal lobe containing a set of nuclei; part of the limbic system; deals with emotion
fornix
a fiber bundle that connects the hippocampus with other parts of the brain, including the mammillary bodies of the hypothalamus; part of the limbic system
mammillary bodies
a protrusion of the bottom of the brain at the posterior end of the hypothalamus containing some hypothalamic nuclei; part of the limbic system
basal ganglia
important part of the motor system; parts of it are caudate nucleus, the putamen, and the globus pallidus
thalamus
the largest portion of the diencephalon located above the hypothalamus; contains nuclei that project information to specific regions of the cerebral cortex and receive information from it
lateral geniculate nucleus
a group of cell bodies within the lateral geniculate body of the thalamus that receives fibers from the retina and projects fibers to the primary visual cortex
medical geniculate nucleus
a group of cell bodies within the medical geniculate body of the thalamus; receives fibers from the auditory system and projects fibers to the primary auditory cortex
ventrolateral nucleus
a nucleus of the thalamus that receives input from the cerebellum and sends axons to the primary motor cortex
hypothalamus
the group of nuclei of the diencephalon situated beneath the thalamus; involved in regulation of the autonomic nervous system, control of the anterior and posterior pituitary glands, and integration of species-typical behaviors
optic chiasm
an X-shaped connection between the optic nerves, located below the base of the brain just anterior to the pituitary gland
anterior pituitary gland
the anterior part of the pituitary gland; an endocrine gland whose secretions are controlled by the hypothalamic hormones
neurosecretory cell
a neuron that secretes a hormone or hormonelike substance
posterior pituitary gland
the posterior part of the pituitary gland; an endocrine gland that contains hormone-secreting terminal buttons of axons whose cell bodies lie within the hypothalamus
midbrain
the mesencephalon; the central of three major divisions of the brain
mesencephalon
the midbrain; a region of the brain that surrounds the cerebral aqueduct; includes the tectum and the tegmentum
tectum
the dorsal part of the midbrain; includes the superior and inferior colliculi
superior colliculi
protrusions on top of the midbrain; part of the visual system
inferior colliculi
protrusions on top of the midbrain; part of the auditory system
brain stem
the stem of the brain, from the medulla to the midbrain, excluding the cerebellum
tegmentum
the ventral part of the midbrain; includes the periaqueductal gray matter, reticular formation, red nucleus, and substantia nigra
reticular formation
a large network of neural tissue located in the central region of the brain stem, from the medulla to the diencephalon
periaqueductal gray matter
the region of the midbrain surrounding the cerebral aqueduct; contains neural circuits involved in species-typical behaviors
red nucleus
a large nucleus of the midbrain that receives input form the cerebellum and motor cortex and sends axons to motor neurons in the spinal cord
substantia nigra
a darkly stained region of the tegmentum that contains neurons that communicate with the caudate nucleus and putamen in the basal ganglia
hindbrain
the most caudal of the three major divisions of the brain; includes the metencephalon and the myelencephalon
cerebellum
a major part of the brain located dorsal to the pons, containing the two cerebellar hemispheres, covered with the cerebellar cortex; an important component of the motor system
deep cerebellar nuclei
nuclei located within the cerebellar hemispheres; receive projections from the cerebellar cortex and send projections out of the cerebellum to other parts of the brain
cerebellar cortex
the cortex that covers the surface of the cerebellum
cerebellar peduncle
one of three bundles of axons that attach each cerebellar hemisphere to the dorsal pons
pons
the region of the metencephalon rostral to the medulla caudal to the midbrain and ventral to the cerebellum; important in sleep and arousal
medulla oblongata
the most caudal portion of the brain; located in the myelencephalon, immediately rostral to the spinal cord; regulates the cardiovascular system, respiration, and skeletal muscle tone
spinal cord
the cord of nervous tissue that extends caudally from the medulla
cauda equina
a bundle of spinal roots located caudal to the end of the spinal cord
caudal block
the anesthesia and paralysis of the lower part of the body produced by injection of a local anesthetic into the cerebrospinal fluid surrounding the cauda equina
dorsal root
the spinal root that contains incoming (afferent ) sensory fibers
ventral root
the spinal root that contains outgoing (efferent) motor fibers
spinal root
a bundle of axons surrounded by connective tissue that occurs in pairs which fuse and form a spinal nerve
cranial nerve
a peripheral nerve attached directly to the brain
vagus nerve
the largest of the cranial nerves, conveying efferent fibers of the parasympathetic division of the autonomic nervous system to organs of the thoracic and abdominal cavities
olfactory bulb
the protrusion at the end of the olfactory nerve; receives input from the olfactory receptors
spinal nerve
a peripheral nerve attached to the spinal cord
afferent axon
an axon directed toward the central nervous system, conveying sensory information
dorsal root ganglion
a nodule on a dorsal root that contains cell bodies of afferent spinal nerve neurons
efferent axon
an axon directed away from the central nervous system conveying motor commands to muscles and glands
somatic nervous system
the part of the peripheral nervous system that controls the movement of skeletal muscles of transmits somatosensory information to the central nervous system
autonomic nervous system
the portion of the peripheral nervous system that control the body’s vegetative functions
sympathetic division
the portion of the autonomic nervous system that controls functions that accompany arousal and expenditure of energy
sympathetic ganglia
nodules that contain synapses between preganglionic and postganglionic neurons of the sympathetic nervous system
sympathetic ganglion chain
one of a pair of groups of sympathetic ganglia that lie ventrolateral to the vertebral column
preganglionic neuron
the efferent neuron of the autonomic nervous system whose cell body is located in a cranial nerve nucleus of in the intermediate horn of the spinal gray matter and whose terminal buttons synapse upon postganglionic neurons in the autonomic ganglion
postganglionic neuron
neurons of the autonomic nervous system that form synapses directly with their target organ
parasympathetic division
the portion of the autonomic nervous system that controls functions that occur during a relaxed state
