The Limbic System
The Limbic System
Most reptiles and lower order organisms only have the “old brain”, the evolutionarily oldest part of the brain responsible for vital tasks such as breathing and sleeping, whereas higher order organisms have a limbic system. The old brain is comprised of the pons, the medulla oblongata, the brain stem, the thalamus, the cerebellum, and the reticular formation. The reticular formation is a network inside of the brain stem, part of the “old brain” that is essential for arousal (sleeping, walking, pain perception, and other important functions). While the old brain is important, it is very limited in what it can do. The limbic system, however, is associated with higher thinking and is present in more evolutionary progressed organisms …show more content…
Its main function is to protect the brain by acting as cushion within the skull and as a shock absorber for the nervous system. The CSF also circulates nutrients and chemicals filtered from the blood, as well as removes waste products from the brain.
· Blood Brain Barrier: BBB is formed by brain endothelial cells and is a significant mechanism for protecting the brain from fluctuations in plasma composition, and circulating agents such as neurotransmitter and xenobiotics capable of disturbing neural function.
The Twelve Cranial Nerves
There are twelve pairs of cranial nerves, all of which originate from the brain stem. The table below shows the twelve cranial nerves and their major functions. A mnemonic often used to help memorize the nerves is: “On old Olympic towering tops a Finn and German viewed some hops.” Cranial Nerve Functions Associated With Each Nerve Pair
I. Olfactory · …show more content…
Hypoglossal · Controls tongue movements Central and Lateral Sulci
The central sulcus is a fissure or fold that separates the parietal lobe from the frontal lobe and the primary motor cortex from the primary somatosensory cortex. It is a prominent landmark of the brain. The lateral sulcus divides both the frontal and parietal lobe above from the temporal lobe below. The lateral sulci are also known as the fissure of Sylvius and the central sulci is also referred to as fissure of Rolando. The folds created by the sulci increase the amount of cerebral cortex that can fit in the skull, in other words the surface area. Basal Nuclei and Cerebral Cortex Fibrils
The term “basal nuclei” is applied to a collection of masses of gray matter situated within each cerebral hemisphere. In the central nervous system, a collection of neuron cell bodies, the soma and dendrites, is called a nucleus. This differs in the peripheral nervous system where the same thing is referred to as a ganglion; the only exception to this rule is the basal ganglia in the brain. The basal nuclei and ganglia play an important role in the control of posture and voluntary movement. Cerebral cortex fibrils and nerve cells compose the folds that make up the outer layer of gray matter that covers the cerebral hemisphere in the brain of many vertebrate
Most reptiles and lower order organisms only have the “old brain”, the evolutionarily oldest part of the brain responsible for vital tasks such as breathing and sleeping, whereas higher order organisms have a limbic system. The old brain is comprised of the pons, the medulla oblongata, the brain stem, the thalamus, the cerebellum, and the reticular formation. The reticular formation is a network inside of the brain stem, part of the “old brain” that is essential for arousal (sleeping, walking, pain perception, and other important functions). While the old brain is important, it is very limited in what it can do. The limbic system, however, is associated with higher thinking and is present in more evolutionary progressed organisms …show more content…
Its main function is to protect the brain by acting as cushion within the skull and as a shock absorber for the nervous system. The CSF also circulates nutrients and chemicals filtered from the blood, as well as removes waste products from the brain.
· Blood Brain Barrier: BBB is formed by brain endothelial cells and is a significant mechanism for protecting the brain from fluctuations in plasma composition, and circulating agents such as neurotransmitter and xenobiotics capable of disturbing neural function.
The Twelve Cranial Nerves
There are twelve pairs of cranial nerves, all of which originate from the brain stem. The table below shows the twelve cranial nerves and their major functions. A mnemonic often used to help memorize the nerves is: “On old Olympic towering tops a Finn and German viewed some hops.” Cranial Nerve Functions Associated With Each Nerve Pair
I. Olfactory · …show more content…
Hypoglossal · Controls tongue movements Central and Lateral Sulci
The central sulcus is a fissure or fold that separates the parietal lobe from the frontal lobe and the primary motor cortex from the primary somatosensory cortex. It is a prominent landmark of the brain. The lateral sulcus divides both the frontal and parietal lobe above from the temporal lobe below. The lateral sulci are also known as the fissure of Sylvius and the central sulci is also referred to as fissure of Rolando. The folds created by the sulci increase the amount of cerebral cortex that can fit in the skull, in other words the surface area. Basal Nuclei and Cerebral Cortex Fibrils
The term “basal nuclei” is applied to a collection of masses of gray matter situated within each cerebral hemisphere. In the central nervous system, a collection of neuron cell bodies, the soma and dendrites, is called a nucleus. This differs in the peripheral nervous system where the same thing is referred to as a ganglion; the only exception to this rule is the basal ganglia in the brain. The basal nuclei and ganglia play an important role in the control of posture and voluntary movement. Cerebral cortex fibrils and nerve cells compose the folds that make up the outer layer of gray matter that covers the cerebral hemisphere in the brain of many vertebrate