What is the myelination difference between white and gray matter?
Gray is short, non-myelinated neurons
White composed of with and without myelin
The cerebral hemispheres and the cerebellum have an outer layer or "bark" of ____ called ____.
Grey matter
Cortex
The ventricular chambers are filled with CSF and line by ____ cells, a type of neuroglia.
Ependymal
The pair ____ ventricles, one deep with each cerebral hemisphere, are large c-shaped chambers that reflex the pattern of cerebral growth.
Lateral
What ventricular chamber's structure reflect the cerebral growth?
Lateral ventricles
What separated the lateral ventricles?
Septum Pellucidum
Each lateral ventricle communicates with the narrow 3rd ventricle in the diencephalon via a channel called ____.
Intraventricular foramen
What connects the 3rd ventricle to the 4th?
Cerebral aqueduct
What are the 3 opening that mark the walls of the 4th ventricle?
Paired lateral apertures on its side walls.
Median to its roof
What connects the 4th ventricle to the subarachnoid space, a fluid filled space surrounding the brain?
Its apertures
What marks the seperation of the cerebral hemispheres?
Longitudinal fissure
What mark the separation of the cerebral hemispheres to the cerebellum below?
Transverse cerebral fissure
What sulcus marks he frontal from the parietal lobe?
Central
Bordering the central sulcus,
What gyri is there?
Anterior: Precentral gyrus
Post.: Postcentral
What outlines the flap-like temporal lobe and separated it from the parietal and frontal lobes?
Lateral sulcus
Where is the insula?
Deep within the lateral sulcus and forms the part of its floor.
What are basal nuclei?
Island of grey matter situated deep within the white matter
Where is our conscious mind found?
Cerebral cortex
Does the cerebral cortex have any never fibers?
No
Specific motor and sensory functions are localized in discrete cortical areas called . . .
Domains
3 functional areas of the cortex?
Motor
Sensory
Association
All neurons in the cortex are what type of neurons?
Interneurons
Where can you find the motor areas in the brain?
Posterior portion of the frontal lobe
Broca's area and frontal eye field area are part of the sensory function group.
T or F
False, they are part of the motor
Where is the primary motor cortex found?
Precentral gyrus
Large neurons in the primary motor cortex called ____, allow us to consciously control movements.
Pyramidal
Pyramidal cells from the prim. motor cortex's long axons project to the spinal cord, forming massive motor tracts called . . .
Pyramidal tracts or
Corticospinal tracts
Motor humunculus implies a __ to __ correspondence between cortical neurons and the muscle they control
1
1
Where would you find the premotor cortex?
What does it do?
Anterior to the prim. motor cortex
Sequences motor movements and controls actions that depend continously on sensory feedback
Where can you find the Broca's area in relation to the premotor cortex?
Anterior, inferior
Where the frontal eye field cortex in relation to the premotor cortex?
Anterior, superior to the Broca's area
In what lobes of the brain are sensory cortex located?
Temporal
Insular
Parietal
Occipital
From where does the prim. sensory cortex get its info.
General somatic sensory receptors in the skin
Proprioceptors
Purpose of somatosensory ass. cortex.
Integrate sensory input and relay to prim.
Within the meninges, the two dura layers are fused together except in . . .
Dural venous sinuses
It collects blood from the brain and returns it
In the dural mater what limits excessive movement of the brain
Dural septa
What is a large sickle-shaped fold that dips into the longitudinal fissure, attaching to the crista galli of the ethmoid bone?
Flax cerebri
What runs in the vermis of the cerebellum inferior the flax cerebri?
Flax cerebelli
What dural fold extends into the transverse fissure?
Tentorium cerebelli
Knoblike projections superly through the dura mater and into the superior sagittal sinus
Arachnoid granulations
Compared to blood, CSF is
less protein than plasma
ion concentration different
More Na+, Cl-, and H+
Less Ca+, K+
Choroid plexus ependymal cells are joined by ___ junctions, and they have an ___ pumps that allows them to modify this filtration by actively transporting only certain ions across.
Tight
Ion
Impermeable tight junctions between capillary endothelial cells are a major component of the . . .
Blood brain barrier
Describe the 3 layers of the blood brain barrier
Endothelium of the capillary walls
Thick basal lamina surrounding external face of the capillary
Bulbous feet of the astrocytes clinging to the capillary
The blood barrier is ineffective against
Fat-soluble
Acohol, nicotine,
Where is the blood barrier absent in the brain and why
3
4 ventricules (easy access to neural tissue)
Hypothalamus ( sample chem. comp. of blood)
All neurons in the spinal cord are bipolar
T or F
False, they are multipolar
Dorsal horns consist of . . .
Interneurons
Ventral horns consist of ____ neurons.
Interneurons but mainly somatic motor
Motor neurons in the spinal cord send their axons out to the muscles via ___ that fuse together to becomes the _____ of the spinal cord.
Ventral rootlets
Ventral Roots
What surround the central canal in the spinal cord?
Grey commissure
Ventral grey matter present reflects what?
Amount of muscle innervation at the level
The lat. horn consist of ____ neurons that serve visceral organs
Autonominc motor
Cell bodies of ass. neurons are found in an enlargement called
Dorsal ganglia
2nd and 3rd order neurons are what type of neurons?
Interneurons
Where 1,2, and 3rd neurons reside?
Skin or Proproceptors
Dorsal horn or medullary nuclei
Thalamus
What are the purposes of the neuron orders?
1: Synape with 2nd
2: Transmit to thalamus
3: Relay to somatosensory cortex
Are there any 3rd order neuron in the cerebellum?
No, only thalamus
What two neural pathways travel to the thalamus?
The third travels where?
Dorsal Column-medial lemiscal and Spinothalamic pathway
The Spinocerebellar travels to the cerebellum
Dorsal Column-medial lemniscal neural pathway are formed by the paired tracts of the ____ of the spinal cord- fasciculus ____ and fasciculus ___- and the _____.
Dorsal White Column
Cuneatus
Gracilis
Medial Lemniscus
The medial lemniscus arises in the medulla and terminates in the ____.
Thalamus
What neural pathway carries pain and temp., also touch and pressure?
Spinothalamic
Spinalthalamic consist of what two tracts
Spinocerebellar?
Lat and Ventral
Ventral and dorsal
Do spinothalamic fibers cross over?
Yes
Spinocerebellar pathways convey info about . . .
muscle/tendon stretch
What two groups do descending pathways fall in?
Direct or indirect
Upper of the descending pathway are all ___ _cell and neurons of the subcortical motor nuclei
Lower motor neurons are ____ motor neurons. innervate skeletal muscles
Pyramidal
Ventral horn
Indirect pathways branch jump on and off the pyramidal tracts
T or F
True
What indirect descending tracts maintain posture?
Control muscle flexor?
Head movement?
Reticulospinal and vestibulospinal
Rubrospinal tracts
Tectospinal
What sensory cortex is located in the superior margin of the temp. lobe; next to the lateral sulcus?
Prim. Auditory
The visual ass. cortex surround the . . .
PRim. Cortex
What cortex uses past visual to interprete
Visual ass. cortex
Where is the visual area cortex?
Posterior most of the occipital lobe
Deep in the calcarine sulcus
Vestibular cortex is where
Olfactory
Gustatory
Visceral
Posterior portion of insula; adjacent to parietal cortex
Med. aspect of temp. lobe
Insula; deep in temp. lobe
Post. to gustatory cortex
Largest commissure of brain
Cerebral callosum
What can you find in the pirform lobe of the temp. lobe?
Olfactory cortex
Function part of the brain dealing with intellect, complex learning abilities
Anterior ass. area
Area play a part in face recogniction
Part of the temp., parietal, and occ. lobe?
Post. Ass. area
What area includes the hippicampus, parahippi., cingulate gyrus?
