The Evolution of the Nervous System: Invertebrates vs. Vertebrates a useful Instrument and Model to Research New Pharmacological Strategies in some Human Neurodegenerative Conditions

The Evolution of the Nervous System: Invertebrates vs. Vertebrates a useful Instrument and Model to Research New Pharmacological Strategies in some Human Neurodegenerative Conditions Mauro Luisetto1*, G Ibrahim2, Oleg latyschev3 and Muhammad Akram4 1Branch Natural Science, Applied Pharmacologist, Italy 2Department of Zoology, Alexandria University, Egypt 3President IMA Academy, India 4Department of Eastern Medicine, Government College University, Pakistan *Corresponding author: Mauro Luisetto, IMA academy, branch Natural Science, applied pharmacologist, Italy. To Cite This Article: Mauro Luisetto. Physiology of The Dependence on Chemical And Psychogenic Psychoactive Factors. Am J Biomed Sci & Res. 2019 5(5). AJBSR.MS.ID.000960. DOI: 10.34297/AJBSR.2019.05.000960. Received: October 11, 2019; Published: October 16, 2019 Copy Right@Mauro Luisetto


If this function is less physiologically -anatomically developed
is difficult that this animal can show DA.
Is a Paradox, but in evolutive pattern of superior vertebrates something goes wrong?
The different vulnerability of CNS neurons in the different place of the brain or spinal cord seem to tell us that in evolution the new structure added to the oldest are more vulnerable.
For this reason, is crucial to set the neurodegenerative disease under an evolutionary Approach.
A more complex nervous system (invertebrates vs vertebrates) create a very different organ with advantages but also disadvantages.

System (by Gaber Ibrahim)
In the lower multicellular animals, such as porifers or sponges, there is no rudiment of nerves. We begin to see neurons, cells that conduct nerve stimuli, in coelenterates. In cnidarian polyps these cells appear scattered throughout the body, forming a network without much organization. There is no nerve center in these animals that runs this network. Each external stimulus acting on a point on the body is accompanied by a merely local response, determining a nerve impulse that propagates with decreasing intensity as it moves away from the stimulus's starting point.
Cnidaria have a diffuse nervous system.

Cnidarian Phylum (corals, anemones, hydras and jellyfish)
The more primitive Porifers (sponges) do not have a nervous system. In Cnidaria, there is a disordered network of neurons. And if a nerve pulse is triggered in one of them, it is transmitted to all cells that communicate with it through synapses, and from these to others, resulting in poorly elaborated responses -such as "pulsating" movements in living water when it's swimming. It is the most primitive type of nervous system, called Diffuse Nervous System.

In Flatworm Worms (such as planar worms, for example)
Neurons associate together to form nerve threads attached to some structures -the nerve ganglia in the head. These ganglia already represent precarious nerve centers in coordinating body activities. In each ganglion there is a higher concentration of neurons. The ganglionic nervous system begins to perfect in the annelids.
In them, there is a larger conglomeration of neurons in the head, forming the cerebroid ganglia, which play a primitive brain role in commanding the other ganglia. From the cerebroid ganglia arise the periesophageal ganglia, which relate to a double ventral ganglionic nerve chain. Along this chain there are a pair of ganglia for each body segment. These ganglia also have marked autonomy over the specific activities of the surrounding body area.

In Annelids
Notwithstanding the presence of cerebroid ganglia, the pairs of ganglia along the ventral nerve chain have a great deal of autonomy, so a worm, even after being cut in half, continues to move the two pieces apart.
The cerebroid ganglia are even more developed in arthropods, especially insects.
In bilateral symmetry invertebrates (Platelminths, Nematelmints, Annelids, Molluscs and Arthropods) the nervous system is in the ventral region of the body and is organized as one or more longitudinal nerve cords presenting two or more nerve ganglia, whether functioning as command centers along its length.
In the possessors of many nerve ganglia, those in the anterior region-cerebroid ganglia are more developed and function as a rudimentary brain that controls the other ganglia. This type of nervous organization is called the ganglionic nervous system.

In Mollusca
The nervous system is centralized and ganglionic, with three parts of nerve ganglia from which nerves go to different parts of the body. Sensory, visual, tactile, chemoreceptor and balance structures are present. The cephalopods have a large cerebroid ganglion that resembles the brain of vertebrates.

In gastropods
The nervous system consists of a set of ganglia and cords that are distributed throughout the body and innervate the different organs.
The set of sensory organs comprises eyes, tentacles, asphradium and statocysts. The eyes, in the most primitive forms, are located at the ends of the tentacles and consist of simple depressions containing pigment and photoreceptor cells. In more advanced gastropods, depression closes, and a cornea and a lens are distinguished. The tentacles have eyes and tactile and chemoreceptor cells. Statocysts are important sensory cells for balance. Available only in species with gills, appears to function as an olfactory and chemoreceptor organ.
Take a close note: The ganglionic nervous system, which characterizes invertebrates, has its double chain of lymph nodes arranged ventrally in the animal, that is, running along the ventral surface of the body. This system is in stark contrast to the vertebrate brain-spinal nervous system that we will see next. The cerebrospinal nervous system is in the dorsal position, descending from the head along the back of the animal [1].
cerebrospinal nervous system. It is made up of a "thirst" -the CNS (central nervous system) -and a network of nerves that break out and distribute throughout the body -the peripheral nervous system. Vertebrates 4.1.1. The Central nervous system: The CNS is formed by the brain and spinal cord. The brain, in turn, comprises the following portions: brain, cerebellum, protuberance (pons or menencephalon) and bulb.
In the lower vertebrates, from fish to birds, the cerebral hemispheres have a smooth surface. Such animals are considered diencephalon (smooth brain). In mammals, however, grooves and circumvolutions appear, giving the brain a surface full of undulations. For this reason, mammals are called gyrencephalon (brain with turns or curves). This transformation brought a great advantage for mammals: At the same volume, a circumvoluted brain has a considerably larger surface than if it had smooth hemispheres. As it is on the surface of the brain (cerebral cortex, with gray matter) that lie the bodies of neurons, the more grooves and convolutions the brain has, the larger its cortex, the larger the number of neurons, and thus the more efficient and improved it is.
The gray matter is placed on the surface of the brain and is where the bodies of neurons accumulate. It is in them that the information is stored, the senses are perceived, the data obtained from external stimuli are "processed". Also, from the neurons depart the orders for muscle contractions or for glandular secretions etc. This superficial area is the cerebral cortex. It has the greatest importance in the degree of development of a species.
The cerebral cortex is all divided into zones, like a map. Each area (some small, some large) represents a nerve center. Nervous centers are numerous throughout the brain, such as the centers of sight, hearing, smell, taste, pain, hunger, cough, tickling, anger, motor coordination (this is very wide and subdivides into areas corresponding to the various points of the body), the visual association for reading, in addition to the centers of respiratory, cardiac regulation, the thermoregulatory center, etc. The cortex is, as it turns out, the "seat" of control of conscious and unconscious acts as well as intelligence.
The brain of a crocodile is, of course, larger than a brain of a mouse. However, the crocodile, as a reptile, is lissencephalon, while the mouse, as a mammal, is a gyrencephalon. Therefore, the extension of the cerebral cortex of the mouse is larger than that of the crocodile, justifying greater rodent intelligence. That is why, in circuses, animal shows predominantly exhibit mammals.
In the deepest region of the brain lies the white mass. In it, there are practically no bodies of neurons, but only their branches (dentites and axons).
The cerebellum, pons, and bulb are also very important because they enclose nerve centers that regulate various functions of relevant role. Breath and temperature controls are in the bulb.
Control of body balance is in the cerebellum.
Aside from the brain, the remainder of the CNS consists of the spinal cord (or spinal cord). It is a long cord of nervous structure that runs along the dorsum inside the spinal canal. It is therefore protected to its full extent by the spine. In spinal cord the gray mass (as opposed to the brain) is in the center and the white mass in the periphery.
White matter is buried deep in the brain and the gray matter is mostly found on the brain's -cortex.
The spinal cord that transmits nerve impulses to and from the rest of the body, has an opposite arrangement: gray matter at its core with insulating white matter on the outside.
The brain white matter is made up by axon tracts, the long, spindly appendages of some brain cells.
These tracts transmit the electrical signals that the brain neurons, to communicate.
They're wrapped in a fatty-layer named myelin, this insulates axons, allows them to conduct signals in very quickly way, much like rubber insulation does for electrical wires.
The type of fat in myelin makes it seem white.
Gray matter is mostly neuron cell bodies and non-neuron brain the cells named glial cells, that provide nutrients and energy to the neurons.
They help in the transport of the glucose into the brain, clean the brain of excess chemicals and may even affect the intensity of the neuron' s-communications systems.

Function of Gray Matter
a) Gray matter-heavy-brain regions include those that control muscular /sensory activity.

Copy@Mauro Luisetto
b) The outer layer of the brain, the cerebral cortex, consists of columns of gray matter neurons, with white matter located underneath.
c) This area is essential to many facets of higher learning functions, attention, memory, and thought.
d) The cerebellum is essential for motor control/ coordination/ and precision of movements.    On its way, the spinal cord emits the spinal nerves, always in pairs. And you may notice that these nerves are closely related to gray matter.

Function of White
Many reflex acts are controlled directly by the spinal cord without brain interference. But in most cases, nerve stimuli reaching this organ are then transmitted to the brain, first reaching the diencephalon (region covering the hypothalamus) and then radiating to the most varied areas of the brain.
Is possible to verify that during vertebrate's evolution increased brain volume vs inferior vertebrates and this was responsible of the opposite architecture of brain vs spinal cord related white-grey matter anatomy.
The cortex is more focused in the new superior cognitive function's vs spinal cord Whit more specialization in condition of the stimuli [2].

The Peripheral Nervous System
The PNS consists of the internal network of nerves that depart from the CNS and are distributed throughout the body (motor nerves) and from nerves that come from all areas of the body and converge on the CNS (sensory nerves). Of course, there are mixed nerves whose characteristics include those of all types mentioned above, that is, they carry all orders of the CNS to the various points of the body and at the same time transmit the sensory perceptions of those same points to the CNS.
We can then say that the PNS (peripheral nervous system) comprises all the nerves in our body. Many of these nerves act on the will of the individual, revealing voluntary action. These voluntary action motor nerves, along with the sensory nerves (which allow us to see, hear, feel pain, smell, taste, heat or cold etc.), offer the individual the possibility to relate to the environment. Therefore, they form what we may call the nervous system of relationship life.
This system contrasts with another large number of nerves that act without the individual's conscience or will, regulating the activity of numerous organs such as the heart, stomach, intestines, diaphragm movements, salivary gland secretions, the pupil diameter etc.
These involuntarily acting nerves, which work without one even suspecting, together form the autonomic nervous system or the vegetative life nervous system.
There are lesions that destroy areas of the CNS, completely nullifying the nervous system acting on the relationship life nervous system but leaving the nervous system of the vegetative life intact. When this occurs, the person becomes unrelated to the world around him and goes on to live an extremely vegetative life

Am J Biomed Sci & Res
Copy@ Mauro Luisetto (the organs work well, but the individual seems to feel nothing or respond to external stimuli).
It is common to call the nervous system of life a somatic nervous system relation (from the Greek soma, "body"), which does not seem very logical to us, since the autonomic nervous system, acting on the various parts of the body, is, consequently also somatic.
The nervous system of relationship life comprises nerves that originate directly in the brain (particularly, the brain, cerebellum, pons or bulge, and, more numerously, the bulb) and nerves that originate in the spinal cord. We then distinguished cranial and spinal nerves, respectively.
Cranial nerves are those that are born directly from the brain.
In mammals they number 12 pairs (in other vertebrates there are only 10 pairs). Some are sensitive; others, engines; still others are mixed. All are cataloged by numbers. Often, a pair is referred to by its number, not by its name.
Thus, it is mandatory to know the 12 pairs of cranial nerves by their order numbers:

1.
Olfactory (sensitive): It transmits to the brain the impulses that give the perception of smell.

2.
Optical (sensitive): Brings to the brain the impulses that provide the visual sensations ( Figure 3).

8.
Acoustic or Atrio-cochlear (sensitive): One of its branches leads to the brain impulses that will give sound perceptions.
The other leads to the cerebellum impulses responsible for the notion of body balance.

Glossopharyngeal (mixed): Transmits the impulses that
give the perception of taste and moves the tongue. 10. Pneumogastric or Vagus (mixed): It acts on the thoracic and abdominal organs and is the main nerve of the parasympathetic system.
11. Spinal, Spinal or Accessory (motor): Acts on the shoulder muscles (shoulder slapping of the naughty).
They all act on organs and muscles from head to shoulder. Only the pneumogastric or vagus goes into the body and innervates the viscera, such as the heart, stomach, intestines and other organs.
In fact, this is the only cranial pair that has involuntary action, therefore belonging to the autonomic nervous system.
The spinal nerves are all born from the spinal cord, but they go to different parts of the body, such as arms, trunks and legs. They comprise 31 pairs and are all mixed, that is, they transmit sensations of the skin and organs to the spinal cord, as they transmit its motor orders to the muscles.
Each spinal nerve contains sensory fibers, which bring to the medulla sensory perceptions of a region of the body, and motor fibers, which carry motor stimuli from the medulla to these regions.
The spinal nerves emerge from the medulla through two rootsanterior root and posterior root -which join just below to form the nerve itself.
Posterior roots (with sensory fibers) are afferent to the medulla, as they conduct the stimulus towards it. The anterior roots (with motor fibers) are efferent in relation to the medulla, because they carry stimuli that move away from it.
To its greatest extent, therefore, each spinal nerve encloses sensory and motor fibers and proceeds as a "two-way road". From the sensory fibers come the perceptual stimuli and from the motor fibers the command commands.
Transition (or association) neurons can make the connection between a sensory neuron and a motor neuron: A. on the same side and at the same level as the gray matter of the medulla; Surely you have ever touched a finger harder than you expected on the tip of a needle. And he withdrew his finger abruptly, so quickly

Am J Biomed Sci & Res
Copy@Mauro Luisetto that it would not be possible or consciously for him. This fact is an example of arc reflex. The reflex arc is the immediate response to arousal of a nerve without the interference of the individual's will (and sometimes even consciousness).
In the above example, the stimulus ran through the sensory fibers of a spinal nerve, bypassed the gray matter of the spinal cord by the association neuron, and returned through the motor fibers of the spinal nerve, reaching the muscles of the arm and hand, causing them to contract. and remove the finger from the tip of the needle.
Many reflexes are by medullary mechanism only. The rotulian or patellar reflex, which the doctor investigates a small blow to the rotulian tendon (knee), denotes through the sudden response of the musculature, involuntarily kicking the air, that the spinal nerves of this region, as well as the medulla, are perfect and in good working order.
But some reflexes are more complex and involve stimuli that go to and return to the cerebral cortex bringing orders to the marrow.
From the analysis of the figure above, you can see: At the level of the bulb, stimuli from one side of the body transfer to the opposite -side of the brain, just as motors coming from one cerebral hemisphere cross at the level of the bulb or medulla. Across the body in a reflex involving the medulla and the brain, the sensory stimulus moves back and forth at the level of the bulb, but the motor response coming from the brain only reverts to the primitive side at the level of the medulla ( Figure 4) [3].

The Autonomic Nervous System
The autonomic nervous system or neurovegetative system is formed by nerves that work without any dependence on the will or conscience of the individual. These nerves are divided into two large groups: the sympathetic system and the parasympathetic system.
Both groups are antagonistic. In the organ in which the sympathetic nerves act by stimulating, the parasympathetic nerves that will have their act inhibiting. In other organs, the parasympathetic is exciting and the sympathetic is inhibiting.
The heart is stimulated by the sympathetic hair and inhibited by the parasympathetic. The opposite occurs, however, in the gut.
From the antagonism of both groups, the functional balance of the organism arises. When one of the groups becomes disturbed, there is imbalance, and the organic functions begin to disturb.
The nerves of the sympathetic system are all born from anteriorbranches of spinal nerves SPN. The nerves of the parasympathetic system form, some also from anterior branches of spinal nerves, while others are born directly from the brain (these are the various branches of the pneumogastric or vagus).
The nerves that make up the ANS (autonomic nervous system) end in glands or smooth muscle tissue. They command, without the individual's conscience, the secretory activity and movements of the viscera in whose structure there are smooth muscles. The nerves of the anastomoses sympathetic system gather their roots and form the sympathetic plexuses, such as the cardiac plexus (which acts on the heart), the solar plexus or celiac plexus (whose branches will form in the liver, stomach and intestines). sacral plexus (which acts on the urogenital organs). All these organs also receive nerve branches from the parasympathetic system.
Neural development is one of the earliest systems to begin and the last to be completed after birth. This development generates the most complex structure in the embryo and the long time period of development means in utero insult during pregnancy may have consequences to development of the nervous system.

Related Human Embryology
The early CNS begins as a simple neural-plate that folds to form a neural groove and then the neural-tube. This early neural is initially open at each end forming the neuro-pores. Within the neural -tube stem cells generate the 2 major classes of cells that make most of the NS: neurons and glia. This cell differentiates into many different types generated with highly specialized functions and shapes [4][5][6].

Material and Methods
After this introduction whit a bibliographic research some relevant literature reported in references is analyzed in order to produce a global conclusion.
All literature was founded on PUBMED database.

Results
Comparing the information reported in the introduction section whit some relevant literature related some human "A ubiquitous feature of the vertebrate anatomy is the segregation of the brain into white and gray matter. If evolution maximized brain-functionality, what is the reason for such segregation? To answer this, we posit that brain functionality requires high inter-connectivity and short conduction delays.
Based on this assumption we re-searched for the optimal brain architecture by comparing different candidate designs. We found that the optimal design depends on the number of neurons, interneuronal connectivity, and axon diameter. the requirement to connect neurons with many fast axons drives the segregation of the brain into white and gray matter. These results provide a possible explanation for the structure of various regions of the vertebrate brain, such as the mammalian neo-cortex and neo-striatum, the avian tele-encephalon, and the spinal cord" [7].

b. Carlos Matute et al. [8]
" "Recent evidence suggests that oligo-dendrocytes can form compact myelin sheaths even in the absence of molecular axonal cues, and that sheath length depends not on properties of the fiber but on the regional origin of the oligo-dendrocyte (brain versus spinal cord " [11].

f. Marc R Freeman et al. [12]
"III. Evolution of Brain Complexity: More and Diversified

Glia Is, Evidently, Better
In-vertebrate glia carry out many functions that are analogous to their vertebrate counterparts. The Strategies to Enhance Nerve Conduction.
Selective pressure for more rapid conduction of the nervous impulse, e.g., in escape or attack behaviors, increasing brain complexity, etc., resulted in 2 types of solutions: decreasing longitudinal resistance or increasing capacitance of axons.
Invertebrates have unsheathing cells but generally lack myelin.
Exceptions are earthworms, copepods, and some crustacean nerves, but myelin and organized white matter tract, as such, are generally found only in vertebrates above the jawless fishes. In ordinarily long fast-firing axons found in many higher organisms. a recent study showed that deficiency of a lactate transporter in oligo-dendrocytes led to axono-pathy and degeneration " [12].

g. Suzana Herculano-Houzel et al. [13]
"Scaling of ratios of neurons over the rest of brain In the absence of data on numbers of neurons and volumetric data for the spinal cord, the ratio of cortical volume over the volume of the medulla has been proposed as a value that should predict cognitive capacity in a manner that is not biased by body mass Variations in this ratio across primate species indeed were well correlated with available behavioral data, but so were brain size, relative cortical volume and encephalization quotient . that dealing strictly with bodily functions, without having body mass as a confounding variable" [13].
"the cerebral white matter, which contains not only axons but around 2 billion neurons and a large, but unknown, number of glia in humans, seems to increase dis-proportionately compared to gray matter as brain size scales across species. Not surprisingly, the cerebral neo-cortex and cerebellum, which contain the largest amounts of white matter, tend to make up greater proportions of larger mammalian brains" [14].

h. Harvey J Karten [15]
"Progressive Telecephalization of Function By the end of the nineteenth century, Herrick et al had demonstrated that the brain-stem of all vertebrates shared a profound level of similarity. the thalamus and telencephalon, except for the olfactory bulbs, seemed to show few commonalities between mammals and non-mammalian vertebrates. This led to the prevailing view that the forebrain of most non-mammalian vertebrates was related to olfactory inputs. The mammalian forebrain, particularly the cortex of the telen-cephalon, was increasingly thought to be novel and unique to mammals. There was no structure in the non-mammalian forebrain that could readily be This led to the erroneous notions that the thalamic and cortical populations of the mammalian brain were unique to mammals and arose abruptly with the evolutionary origin of mammals " [15].
Nat Rev Neurosci. Author manuscript; available in PMC 2008 Aug 12.

i.
Jarvis ED et al. [16] "They noted that the main divisions of the human CNS-the spinal cord, hindbrain, midbrain, thalamus, cerebellum and cerebrum or tele-encephalon-were present in all vertebrates. Edinger, however, noted that the internal organization of the telencephala showed the most pronounced differences between species. In mammals, the outer part of the telencephalon was found to have prominently layered grey matter whereas the inner part The term 'striatum' was used because a large part of the basal ganglia (palaeo-encephalon) in mammals, now commonly called the caudate-putamen, has fibre bundles coursing through it that give it a striated appearance.
The classical view that became dominant was that the primordial telencephalon of fishes had a relatively small pallium and a larger sub-pallium, both of which were entirely devoted to olfactory information processing. The fish sub-pallium was named 'palaeostriatum' (old striatum) and was thought to be the antecedent of the human Globus pallidus. Amphibians were thought to have evolved an 'archi-striatum' (archaic striatum) above the palaeostriatum, which was proposed to be the antecedent of the human amygdala. Reptiles were thought to have evolved a 'neo-striatum' (new striatum) above the archi-striatum, which was proposed to be the antecedent of the human caudate and putamen. The palaeostriatum of reptiles was also thought to have elaborated into an older part (primitivum) and a newer part (augmentatum), both of which were considered homologous to the human globuspallidus. Following this, birds were thought to have evolved a large additional basal ganglia subdivision, the 'hyperstriatum' (hypertrophied striatum), which was considered to be unique to birds.
The fish pallium was named 'palaeo-cortex' and was proposed to be the antecedent of the human olfactory cortex. Reptiles were thought to have evolved an 'archi-cortex', also thought to be olfactory and primitive, that was said to be the antecedent of the human hippocampus. Birds were thought not to have evolved any further pallial regions. By contrast, mammals were thought to have evolved the latest and greatest achievement, a 'neocortex', from the palaeocortex and/or archicortex6. The archi-cortex and/or palaeocortex, with their 2-3 cell layers, were assumed to be primitive; the neocortex, with its 6 layers, was assumed to be more recently evolved and a substrate for more sophisticated behavior.
There were dissenting voices to the classical view. Some of its proponents also made partial or tentative retractions. alternative views were not widely embraced. Instead, the classical view was is quite conserved. By contrast, the organization of the pallial domains of these groups is more varied. The avian hyperpallium has a unique organization that has so far been found only in birds.
This consists of semi-layered subdivisions and might have evolved more recently than the mammalian six-layered cortex, as birds evolved ~50-100 million years after mammals. The DVR (which, in birds, contains the meso-pallium, nido-pallium and arco-pallium) is a nuclear, grey matter formation that is unique to birds and reptiles. The six-layered cortex is unique to mammals, and, as all the main groups of living mammals (monotremes, marsupials and placentals) have a six-layered cortex87, it was presumably inherited from their common therapsid ancestor more than 200 million years ago. Furthermore, new findings indicate that mammals did not arise from reptiles, but from therapsids, and that the last common ancestor of the reptile and mammal lineages was the stem amniotes. As all non-mammalian therapsids are now extinct, it is difficult to trace from stem amniotes to mammals the evolutionary history of mammalian tele-encephalic organizationlayered, nuclear or otherwise. Therefore, the reptilian nuclear pallial organization cannot be assumed to represent the ancestral condition for mammals " [16].

j. Fahima Mayer et al. [17]
Pharmacologic remedy of many brain diseases is difficult because of the powerful drug exclusion properties of the bloodbrain barrier (BBB). Chemical isolation of the vertebrate brain is achieved through the highly integrated, anatomically compact and functionally overlapping chemical isolation processes of the BBB.
These include functions that need to be coordinated between tight diffusion junctions and uni-directionally acting xenobiotic transporters. Understanding of many of these processes has been hampered, because they are not well mimicked by ex vivo models of these changes may have been the brain's increased vulnerability to factors which can trigger AD. This vulnerability may have resulted from the evolutionary legacies that have occurred over the course of the evolution of the human brain, making AD a possible example of antagonistic pleio-tropy. The evolutionary approach allows apparently unrelated data from different disciplines to be combined in a manner that may lead to an improved understanding of complex diseases such as Alzheimer's" [18].

l. Mark R Cookson [19]
"There are a number of neuro-degenerative diseases that principally affect humans as they age, characterized by the loss of specific groups of neurons in different brain regions. Although these are in general sporadic disorders, it is now clear that many of these diseases have a substantial genetic component. As genes are the raw material with which evolution works, we might benefit from understanding these genes in an evolutionary framework.
Here, I will discuss how we can understand whether evolution has shaped genes involved in neurodegeneration and the implications for practical issues such as our choice of model systems for these diseases and more theoretical concerns such as the level of selection against these phenotypes.

m. Carolyn Simon
"New research provides evidence the body has a fast-track brain cleansing system that prevents diseases such as Alzheimer's and maintains brain health. Finding ways to support and enhance this cleansing process could lead to improved outcomes in brain injury and brain disease. Read on to find what scientists have discovered and how cranio-sacral therapy effectively promotes brain health by invigorating this active fluid -cleansing system.
Most of us have heard of the lymphatic system, the collection of vessels and nodes running throughout the body that helps cleanse waste products and is part of the body's immune system. Now a team of neuroscientists at the Univ. of Rochester Medical Center has identified a fascinating fast-track cleansing system in the brain called the glymphatic system. A bulk flow process moves CSF via the arterial system right into the brain tissue, exchanging with the interstitial fluid inside the brain. As it does, it washes through the tissue collecting waste particles that are sitting in between the brain cells. The CSF then enters the venous system via veins within the brain tissue, taking the fluid and the waste it picks up away from the brain. In this way waste material is efficiently removed from the brain tissue, by the CSF, via the circulatory system. We know accumulation of waste and toxic matter in the brain environment adversely affects brain-function". The study adds to the evidence that the star-shaped cells called astrocytes play a leading role in keeping the nervous system in good working order.
In most of the body, a network of vessels carries lymph, a fluid that removes excess plasma, dead blood cells, debris and other waste. But the brain is different. Instead of lymph, the brain is bathed in cerebro-spinal fluid.

n. Walker S Jackson [20]
"The mechanisms under-lying the selective targeting of specific brain regions by different neuro-degenerative diseases is one of the most intriguing mysteries in medicine. it is known that A D primarily affects parts of the brain that play a role in memory, whereas PD predominantly affects parts of the brain that are involved in body movement. The reasons that other brain regions remain un-affected in these diseases are unknown [20] (Figure 5-8).

Experimental project hypothesis:
To verify the hypothesis that evolution pattern is involved in some neuronal vulnerability is possible to observe the incidence of cortical neuro degenerative pathology across the various superior vertebrates ( in example related the increase of cortical cognitive advanced function) then compare this data also with the incidence of other degenerative process in inferior vertebrates. VI. Un-other fact is that DA is a common pathology not only in human but also in other.
VIII. The same other peculiarity is that in spinal cord or in

Clarifications
This work is produced without any diagnostic or therapeutic intent, only to submit to researcher new hypothesis to be verified.