Structure and Layout of Major Brain Areas, Sensory and Motor Pathways Flashcards
What are the lobes of the brain?
Frontal lober, parietal lobe, occipital lobe, temporal lobe and cerebellum
What is a sulcus?
Furrow/valley
What is sulci?
Furrows/valleys
What is a gyrus?
Hill
What are gyri?
Hills
What does the central sulcus separate?
Frontal and parietal lobes
What does the parietal-occipital sulcus separate?
Parietal and occipital lobes
What does the lateral sulcus separate?
The temporal lobe from the frontal and parietal lobes
What does the transverse fissure separate?
Cerebrum from cerebellum
What are the functions of the frontal lobe?
Motor control, language and personality
What are the functions of the parietal lobe?
Somatosensory (afferent sensory information processed)
What are the functions of the occipital lobe?
Vision
What are the functions of the temporal lobe?
Memory and hearing
What is the cerebral cortex also called?
Cerebrum
What is the white matter in the brain called?
Corpus callosum
What is included in the brainstem?
Midbrain, pons and medulla oblngata
What is included in the diencephalon?
Thalamus and hypothalamus
Where is the diencephalon found?
Above the brain stem
Where is the level of the foramen magnum?
At the bottom of the brain stem (in line with the medulla oblongata)
What is the thalamus part of?
The diencephalon and not the brainstem
How many types of white matter are there in the brain?
3
Where is the grey matter in the brain?
The cerebral cortex
Hoe many deep nuclei (cell bodies) are in the brain?
4
What are the types of white matter in the brain?
Commisural Tracts, Projection Tracts and Association Tracts
What do commissural tract axons do?
Cross from side to side (one side of the brain to the other) in both directions
What is an example of a commissural tract?
Corpus callosum
What do projection tract axons do?
Extend between cortex and other CNS areas outside the cerebrum
What is an example of a projection tract?
Corticospinal tract
What do the axons of association tracts do?
Axons are on the same side within the cerebral cortex and allow for communication between brain areas (short or long distance)
What is found before the central sulcus?
The pre-central gyrus
What is found after the central sulcus?
The post-central gyrus
What does the precentral gyrus function as?
The primary motor cortex
What does the primary motor cortex do?
Specific regions of the motor cortex control specific regions of the body
How many neurons between the brain and the effector in the corticospinal pathway?
2 (upper motor neuron - neuron#1 and lower motor neuron - neuron#2)
What pathway is associated with the primary motor cortex?
Corticospinal
Where is the cell body of the upper motor neuron of the corticospinal pathway?
In the primary motor cortex (pre-central gyrus)
Where is the axon of the upper motor neuron of the corticospinal pathway?
Extends from the motor cortex to the spinal cord on the opposite side
Where is the synapse of the upper motor neuron of the corticospinal pathway?
On the lower motor neuron
Where is the cell body of the lower motor neuron of the corticospinal pathway?
In the ventral horn (grey matter) of the spinal cord
Where is the axon of the lower motor neuron of the corticospinal pathway?
Extends out of the spinal cord (ventral root) into the body
Where is the synapse of the lower motor neuron of the corticospinal pathway?
On the skeletal muscle
What does the right pre-central gyrus control?
The skeletal muscle on the left side of the body
What does the left pre-central gyrus control?
The skeletal muscle on the right side of the body
What happens if there is damage to the primary motor cortex?
Muscle weakens and paralysis in region of the body corresponding to the location of damage (on the opposite side to where the damage is in the motor cortex)
What does the post-central gyrus function as?
The primary somatosensory cortex
What does the primary somatosensory cortex do?
Specific regions receive sensory information from specific regions of the body
What pathway is associated with the primary somatosensory cortex?
Dorsal/posterior column pathway
How many neurons between the sensory receptors in the body and the somatosensory neuron in the post-central gyrus?
3
Where is the cell body of the neuron #1 of the dorsal/posterior column pathway?
In the dorsal root ganglion (unipolar ganglion)
What is input to the cell body of neuron #1 of the dorsal/posterior column pathway?
Peripheral fibre (input zone) from sensory receptor in skin
What is the output of the cell body of neuron #1 of the dorsal/posterior column pathway?
Central fibre (output zone) ascends towards brain in dorsal columns (spinal cord white matter)
Where is the synapse of neuron #1 of the dorsal/posterior column pathway?
On neuron #2 in the medulla oblongata
Where is the cell body of neuron #2 of the dorsal/posterior column pathway?
In the medulla oblongata
Where the axon of neuron #2 of the dorsal/posterior column pathway?
Axon crosses to the opposite side and then ascends
Where is the synapse of neuron #3 of the dorsal/posterior column pathway?
On cell body of somatosensory cortex neuron
Where is the cell body of neuron #3 of the dorsal/posterior column pathway?
In the thalamus
Where is the axon of neuron #3 of the dorsal/posterior column pathway?
Ascends to the somatosensory cortex
Where is the synapse of neuron #3 of the dorsal/posterior column pathway?
On the cell body of a somatosensory cortex neuron
What happens if the cell in the somatosensory cortex that receives information from the dorsal column pathway dies?
Ascending information has no place to go and there is no perception of touch in that area if the body on the opposite side to the damage
