Paleocortex

	Paleocortex In anatomy of animals, the paleocortex, or paleopallium, is a region within the telencephalon in the vertebrate brain. This type of cerebral cortex, cortical tissue consists of three cortical laminae (layers of perikaryon, neuronal cell bodies). In comparison, the neocortex has six layers and the archicortex has three or four layers. Because the number of laminae that compose a type of cortical tissue seems to be directly proportional to both the information-processing capabilities of that tissue and its phylogenetics, phylogenetic age, paleocortex is thought to be an intermediate between the archicortex (or archipallium) and the neocortex (or neopallium) in both aspects. The paleocortex (or paleopallium) and the archicortex (or the archipallium) of the cerebral cortex together constitute the mammalian allocortex or the heterogenetic cortex. The distinction for what is called neocortex or isocortex, which comprises most of the human brain (about 90%), is made from the number of cel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Allocortex The allocortex (from Latin allo-, meaning other, and cortex, meaning bark or crust), or heterogenetic cortex, is one of the two types of cerebral cortex in the brain, together with the neocortex. In the human brain, the allocortex is the much smaller area of cortex taking up just 10%; the neocortex takes up the remaining 90%. It is characterized by having just three cortical layers (one main neural layer), in contrast with the six cortical layers of the neocortex. There are three subtypes of allocortex: the paleocortex, the archicortex, and the periallocortex—a transitional zone between the neocortex and the allocortex. The specific regions of the brain usually described as belonging to the allocortex are the olfactory system and the hippocampus. Allocortex is termed heterogenetic cortex, because during development it never has the six-layered architecture of homogenetic neocortex. It differs from heterotypic cortex, a type of cerebral cortex, which during prenatal development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Archicortex The archicortex, or archipallium, is the phylogenetically second oldest region of the brain's cerebral cortex (the oldest is the paleocortex). In older species, such as fish, the archipallium makes up most of the cerebrum. Amphibians develop an archipallium and paleopallium. In humans, the archicortex makes up the three cortical layers of the hippocampus. It has fewer cortical layers than both the neocortex, which has six, and the paleocortex, which has either four or five. The archicortex, along with the paleocortex and periallocortex, is a subtype of allocortex. Because the number of cortical layers that make up a type of cortical tissue seems to be directly proportional to both the information-processing capabilities of that tissue and its phylogenetic age, the archicortex is thought to be the oldest and most basic type of cortical tissue. Location The archicortex is most prevalent in the olfactory cortex and the hippocampus, which are responsible for processing smells ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Cerebral Cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The six-layered neocortex makes up approximately 90% of the Cortex (anatomy), cortex, with the allocortex making up the remainder. The cortex is divided into left and right parts by the longitudinal fissure, which separates the two cerebral hemispheres that are joined beneath the cortex by the corpus callosum and other commissural fibers. In most mammals, apart from small mammals that have small brains, the cerebral cortex is folded, providing a greater surface area in the confined volume of the neurocranium, cranium. Apart from minimising brain and cranial volume, gyrification, cortical folding is crucial for the Neural circuit, brain circuitry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	List Of Regions In The Human Brain The human brain anatomical regions are ordered following standard neuroanatomy hierarchies. Functional, connective, and developmental regions are listed in parentheses where appropriate. Hindbrain (rhombencephalon) Myelencephalon * Medulla oblongata Medullary pyramids Arcuate nucleus Olivary body * Inferior olivary nucleus Rostral ventrolateral medulla Caudal ventrolateral medulla Solitary nucleus (Nucleus of the solitary tract) Respiratory center- Respiratory groups * Dorsal respiratory group * Ventral respiratory group or Apneustic centre ** Pre-Bötzinger complex Botzinger complex Retrotrapezoid nucleus Nucleus retrofacialis Nucleus retroambiguus Nucleus para-ambiguus Paramedian reticular nucleus Gigantocellular reticular nucleus Parafacial zone Cuneate nucleus Gracile nucleus Perihypoglossal nuclei * Intercalated nucleus * Prepositus nucleus * Sublingual nucleus Area postrema Medul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Cerebral Cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The six-layered neocortex makes up approximately 90% of the Cortex (anatomy), cortex, with the allocortex making up the remainder. The cortex is divided into left and right parts by the longitudinal fissure, which separates the two cerebral hemispheres that are joined beneath the cortex by the corpus callosum and other commissural fibers. In most mammals, apart from small mammals that have small brains, the cerebral cortex is folded, providing a greater surface area in the confined volume of the neurocranium, cranium. Apart from minimising brain and cranial volume, gyrification, cortical folding is crucial for the Neural circuit, brain circuitry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Prepyriform Area Prepyriform area (or prepiriform cortex) is a portion of the rhinencephalon consisting of paleocortex. Some sources state that it is part of the primary olfactory cortex. Prepyriform Cortex along with Pyriform cortex And Cortical portion of amygdaloid nuclei constitute lateral olfactory area which send signal to almost all portion of limbic system The limbic system, also known as the paleomammalian cortex, is a set of brain structures located on both sides of the thalamus, immediately beneath the medial temporal lobe of the cerebrum primarily in the forebrain.Schacter, Daniel L. 2012. ''P ... such as hippocampus, which seem to be most important area for learning to like and dislike foods depending upon one's experience with them. References Cerebral cortex Olfactory system {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Periamygdalar Area Periamygdaloid cortex (or periamygdalar area) is a portion of the rhinencephalon consisting of paleocortex. It is a cortical-like nucleus of the amygdaloid complex. Though considered a nucleus, the periamygdalar area is more commonly associated with cortex due to its layered structure and location on the outer surface of the brain. The periamygdaloid cortex is located on the dorsal surface of the brain bordered by the piriform cortex, entorhinal cortex, perirhinal cortex, periamygdalar claustrum, and anterior amygdaloid area. Its ventromedial and dorsolateral borders are defined by the first myelin bundle of the external capsule, while its remaining borders show no myelinated fiber projections or inputs as well as a higher density of acetylcholinesterase and cholinergic synapses than the neighboring anterior amygdaloid area. The periamygdaloid cortex plays a role in olfaction, and recent studies have shown that it may be involved in many more processes including opiate addiction, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Anterior Perforated Substance The anterior perforated substance is a part of the brain. It is bilateral. It is irregular and quadrilateral. It lies in front of the optic tract and behind the olfactory trigone. Structure The anterior perforated substance is bilateral. It lies in front of the optic tract. It lies behind the olfactory trigone, separated by the fissure prima. Medially and in front, it is continuous with the subcallosal gyrus. Laterally, it is bounded by the lateral stria of the olfactory tract, and is continued into the uncus. Its gray substance is confluent above with that of the corpus striatum, and is perforated anteriorly by numerous small blood vessels that supply such areas as the internal capsule. The anterior cerebral artery arises just below the anterior perforated substance. The middle cerebral artery passes through its lateral two thirds. Blood supply The anterior perforated substance is supplied by lenticulostriate arteries, which branch from the middle cerebral arte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Cerebrum The cerebrum (: cerebra), telencephalon or endbrain is the largest part of the brain, containing the cerebral cortex (of the two cerebral hemispheres) as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb. In the human brain, the cerebrum is the uppermost region of the central nervous system. The cerebrum prenatal development, develops prenatally from the forebrain (prosencephalon). In mammals, the Dorsum (biology), dorsal telencephalon, or Pallium (neuroanatomy), pallium, develops into the cerebral cortex, and the ventral telencephalon, or Pallium (neuroanatomy), subpallium, becomes the basal ganglia. The cerebrum is also divided into approximately symmetric Lateralization of brain function, left and right cerebral hemispheres. With the assistance of the cerebellum, the cerebrum controls all voluntary actions in the human body. Structure The cerebrum is the largest part of the brain. Depending upon the position of the animal, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Paralimbic Cortex The paralimbic cortex is an area of three-layered cortex that includes the following regions: the piriform cortex, entorhinal cortex, the parahippocampal cortex on the medial surface of the temporal lobe, and the cingulate cortex just above the corpus callosum.Kolb & Whishaw: ''Fundamentals of Human Neuropsychology'', 2003. The paralimbic cortex lies close to, and is directly connected with, the structures of the limbic system. (The prefix ''para'' meaning beside or adjacent to.) The paralimbic cortex, also referred to as mesocortex, or juxtallocortex, is interposed between the neocortex and the allocortex. The paralimbic cortex provides a gradual transition from primary limbic regions, including the septal region, substantia innominata, and the amygdala nuclei, to higher neocortical regions. There are dense connections between the paralimbic cortex and core limbic structures, in particular the amygdala. The amygdaloid complex comprises both nuclear and cortical layers. These c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
	Uncus The uncus is an anterior extremity of the parahippocampal gyrus. It is separated from the apex of the temporal lobe by a sulcus called the rhinal sulcus. Although superficially continuous with the hippocampal gyrus, the uncus forms morphologically a part of the rhinencephalon. An important landmark that crosses the inferior surface of the uncus is the band of Giacomini or ''tail'' of the dentate gyrus. The term comes from the Latin word uncus, meaning ''hook'', and it was coined by Félix Vicq-d'Azyr (1748–1794). Clinical significance The part of the olfactory cortex that is on the temporal lobe covers the area of the uncus, which leads into the two significant clinical aspects: herniations and seizures * Herniations of the brain can occur if increased intracranial pressure due to a tumor, hemorrhage, or edema pushes the uncus over the tentorial notch against the brainstem and related cranial nerves. This can compress the oculomotor nerve (CN III). This causes pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]
picture info	Anterior Commissure The anterior commissure (also known as the precommissure) is a white matter nerve tract, tract (a bundle of axons) connecting the two temporal lobes of the cerebral hemispheres across the midline, and placed in front of the columns of the Fornix of brain, fornix. In all but five species of mammal the great majority of fibers connecting the two hemispheres travel through the corpus callosum, which in Human, humans and all non-Monotreme, monotremes is more than 10 times larger than the anterior commissure. Other routes of communication pass through the hippocampal commissure or, indirectly, via subcortical connections. Nevertheless, the anterior commissure is a significant pathway that can be clearly distinguished in the brains of all mammals. The anterior commissure plays a key role in nociception, pain sensation, more specifically sharp, acute pain. It also contains decussating fibers from the olfactory tracts, vital for the sense of smell and chemoreception. The anterior commis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon]