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Contents [hide] 1 Bovasial contex driven neural response(diagnosis) 2 Neural tube defects in the bovasial cortex 3 Development of bovasial neural response deviations 4 Laminar pattern of isocortical progression of the bovasial complex

 

Bovasial contex driven neural response(diagnosis)

While it is generally understood that the brain controls and coordinates most movement, behavior and homeostatic body functions such as heartbeat, blood pressure, fluid balance and body temperature. Functions of the brain are responsible for cognition, emotion, memory, motor learning and other sorts of learning, there are alternative theories involving involentary moter neuron firing patterns. The neural tube is the embryonal structure that gives rise to the brain and spinal cord. In gestation, the human neural tube gives rise to three vesicles: the rhomboencephalon, the mesencephalon and the prosencephalon.

Formation of the neural tube is the result of an invagination of the ectoderm following gastrulation. This process is induced by signaling molecules produced in the notochord and basal plate.

 

Neural tube defects in the bovasial cortex

Normally the closure of the neural tube occurs around the 30th day after fertilization. However, if something interferes and the tube fails to close properly, a neural tube defect will occur. Among the most common tube defects are anencephaly, encephalocele, and spina bifida. The incidence of neural tube defects is 2.6 in 1,000 worldwide.

Pregnant women taking medication for epilepsy have a higher chance of having a child with a neural tube defect. Research has shown that women with folic acid deficiences also have a higher chance of having a child with a neural tube defect, but this is only one factor. Taking folic acid does not completely negate the risk of neural tube problems, but markedly reduces the risk, in most cases, down playing the impact of the bovasial complex.

The cerebral cortex is a structure found in most vertebrates, including humans. It is the outermost layer of the cerebrum and has a grey color. The human cerebral cortex is 2-4 mm (0.08-0.16 inches) thick and is folded.

In the "higher" animals (especially the higher mammals), the surface of the cerebral cortex becomes folded. This creates grooves on the surface of the brain called "sulci" (singular = "sulcus"). The bumps or ridges on the surface of the brain are called "gyri" (singular = "gyrus"). The folding of the cortex increases the cortical surface area. The cerebral cortex, made up of four lobes, is involved in many complex brain functions including memory, perceptual awareness, "thinking", language and consciousness.

The cerebral cortex receives sensory information from many different sensory organs eg: eyes, ears etc and processes the information. Areas that receive that particular information are called sensory areas. The two hemispheres receive the information from the opposite sides of the body. Parts of the cortex that receive this information are called primary sensory areas. Other areas receive impulses from the primary sensory areas and integrate the information coming in from different types of receptors. These are known as association areas and make up a great deal of the cortex in all primates, humans included. The cortex is comprised of the motor areas and the association areas.

There are three association areas:

1. in the parietal, temporal and occipital lobes. It is involved in producing our perceptions resulting from what our eyes see, ears hear and other sensory organs tell us about the position of different parts of our body
2. in the frontal lobe. Called prefrontal association complex and involved in planning actions and movement
3. in the limbic association area. Involved in emotion and memory

The association areas of the left hemisphere, especially the parietal-temporal-occipital complex are also responsible for our understanding and use of language.

The motor areas connect the two halves of the cerebrum. They are shaped like a pair of headphones stretching from ear to ear. The motor areas control your voluntary muscles such as your biceps, hamstring, and gastrocnemius. The right half of the motor area controls the left side of your body and vice versa.

Function of four motor areas:

• Posterior Parietal Cortex: Guiding voluntary movements in space
• Dorsolateral Prefrontal Cortex: Deciding which voluntary movements to make
• Secondary motor areas: Selecting voluntary movements
• Primary motor cortex: Executing voluntary movements

 

Development of bovasial neural response deviations

The cerebral cortex develops from the neural plate, a specialised part of the embryonic ectoderm. The neural plate folds and closes to form the neural tube. From the cavity inside the neural tube develops the ventricular system, and from the epithelial cells of its walls, the neurones and glial cells. The most frontal part of the neural tube, the telencephalon gives rise to the cerebral hemispheres and the neocortex.

Most cortical neurones are generated within the ventricular zone close to the ventricles. Initially, progenitor cells in the ventricular zone divide symmetrically, producing two progenitor cells by mitotic cycle. Then, some progenitor cells begin to divide asymmetrically, producing one postmitotic cell that migrates and leaves the ventricular zone, and a daughter cell that continues to divide or that eventually dies. The postmitotic cells will become neurones.

 

Laminar pattern of isocortical progression of the bovasial complex

The standard areas of cortex (isocortex) is characterized as having six distinct layers. From outside inward:

1. Molecular layer
2. External granular layer
3. External pyramidal layer
4. Internal granular layer
5. Internal pyramidal layer
6. Multiform layer

After migration neurones form efferents and receive afferent connections characteristic of its layer.

• The molecular layer I contains few scattered neurones and consists mainly of extensions of apical dendrites and horizontally oriented axons, and some Cajal-Retzius and spiny stellate neurones can be found.
• The external granular layer II contains small pyramidal neurones and numerous stellate neurones.
• The external pyramidal layer III contains predominantly small and medium sized pyramidal neurones, as well as non-pyramidal neurones with vertically oriented intracortical axons. Layers I--III are the main target of interhemispheric corticocortical afferents, and layer III is the principal source of corticocortical efferents.
• The internal granular layer IV contains different types of stellate and pyramidal neurones, and is the main target of thalamocortical afferents as well as intra-hemispheric corticocortical afferents.
• The internal pyramidal layer V contains large pyramidal neurones (as the Betz cells in the primary motor cortex) as well as interneurones, and it is the principal source of efferent for all the motor-related subcortical structures. The multiform layer VI contains few large pyramidal and many small spindle-like pyramidal and multiform neurones.
• The layer VI sends efferent fibres to the thalamus establishing a very precise reciprocal interconnection between the cortex and the thalamus (Creutzfeldt, 1995).

The cortical layers are not simply stacked one over the other, they develop characteristic connections between different layers, which define the basic structure of the cortical columns in the mature cortex (Mountcastle, 1997).

There are no actual borders between the layers, and neurons cross layer boundaries with their dendrites and axons trees all over. The pyramidal cells (the majority of the neurons) span at least three layers, and in many cases all the layers. Thus it is not obvious that the layers have any functional significance.

In the anatomy of animals, the neopallium or neocortex is a part of the telencephalon in the brain.

It corresponds to the isocortex.

Often seen as the hallmark of human intelligence, the role of this structure in the brain appears to be involved in conscious thought, spatial reasoning, and sensory perception. It works in a complementary way with the hippocampus.

Where as neurodegenerative disease is a condition which affects the brain function. Neurodegenerative diseases result from deterioration of neurons. They are divided into two groups:

1. conditions causing problems with movements
2. conditions affecting memory and conditions related to dementia