Neuroanatomy practical Flashcards
midsaggittal plane
divides the brain into equal left and right halves. sections parallel to the midsagittal plane are in the sagittal plane.
horizontal plane
perpendicular to the midsaggital and coronal plane. parallel to the ground. a single section in this plane could pass through both the eyes and the ears. divides the brain into dorsal and ventral segments.
coronal plane
perpendicular to midsaggital plane and horizontal plane. a single section in the plane could pass either through both eyes, or both ears. splits the brain into anterior and posterior parts
what is the forebrain consist of?
cerebral cortex, embedded nuclear groups in the white matter of the cortex, such as caudate and lentiform nuclei, thalamus and hypothalamus.
midbrain ?
tectum and tegmentum. look for cerebral aqueduct which CSF-filled and is connected rostrally with the third ventricle of the diencephalon, and caudally with the forth ventricle of the hindbrain.
hind brain ?
rostral hindbrain - cerebellum and pons.
caudal hindbrain - medulla and medullary pyramids.
at core of hindbrain lies the fourth ventricle contents rostrally with the aqueduct
what is brainstem composed of ?
(thalamus and hypothalamus, diencaphalon) midbrain, pons, medulla.
describe the dura matter
touch inelastic collagenous membrane that surrounds the brain and spinal cord.
arachnoid matter
has the appearance and consistency of a spider web. flattened cells form a continous outer membrane. This membrane prevents the free flow of ions and molecules into or out of the subarachnoid space. This space is bridged by cellular trabeculae passing between the outer cellular layers of the arachnoid and the pia.
what is the space between the dura matter and arachnoid matter called ?
subdural space.
what is the space between the pia matter and the arachnoid matter ?
subarachnoid space.
pia matter
inner most layer, formed of a thin, delicate membrane that adheres closely to the surface of the brain. It follows every indentation and fissure of the surface of the brain.
describe the medulla
caudal to the cerebellum and pons. is continuous with the spinal cord through a hole in the base of the skull called the foramen magnum
what is the name of the groove that lies along the mid-ventral line of the medulla
the median longitudinal fissure
On either side of the median longitudinal fissure are slightly elevated ridges known as
the pyramids
how is the medulla continuous with the spinal cord ?
through a hole in the base of the skull called the foramen magnum
what does the inferior cerebellar peduncles convey?
inferior cerebellar peduncles convey a variety of afferent fibre systems to the cerebellum, including those from the spinal cord and from the inferior olivary nuclei and a small number of efferent fibres from the cerebellum concerned with the mechanisms for maintaining balance and posture
middle cerebellar peduncles
links the cerebellum with the pons
superior cerebellar peduncles
connects the cerebellum with the midbrain
what is the dorsal surface of the medulla obscured by ?
the cerebellum
describe the gracile nuclei
gracile nucleus is one of the dorsal column nuclei that participate in the sensation of fine touch and proprioception
where do axons from the gracile and cuneate nuclei project to
the axons of the dorsal column nuclei ascend within a white matter tract called the medial lemniscus. the medial lemniscus rises the medulla, pons and midbrain and its axons synapse upon neurons of the ventral posterior (VP) nucleus of the thalamus.
where do the axons or the dorsal column pathway decussate
the axons decussate (sensory decussation) at the ventral and medial medulla crossing the midline just rostral to the pyramidal decussation of the lateral corticospinal tract
what makes up the floor of the fourth ventricle
the dorsal surface of the pons and most of the medulla