|
Hippocampus Anatomy
Hippocampus anatomy describes the physical aspects and properties of the hippocampus, a neural structure in the medial temporal lobe of each cerebral hemisphere of the brain. It has a distinctive, curved shape that has been likened to the hippocampus (mythology), sea-horse creature of Greek mythology, and the Sheep, ram's horns of Amun#New Kingdom, Amun in Egyptian mythology. The general layout holds across the full range of mammals, although the details vary. For example, in the rat, the two hippocampi look similar to a pair of bananas, joined at the stems. In humans and other primates, the portion of the hippocampus near the base of the temporal lobe is much broader than the part at the top. Due to the three-dimensional curvature of the hippocampus, two-dimensional sections are commonly presented. Neuroimaging can show a number of different shapes, depending on the angle and location of the cut. Cerebral cortex, Cortical parts from the temporal lobe, parietal lobe, and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Parahippocampal Gyrus
The parahippocampal gyrus (or hippocampal gyrus') is a grey matter cortical region, a gyrus of the brain that surrounds the hippocampus and is part of the limbic system. The region plays an important role in memory encoding and retrieval. It has been involved in some cases of hippocampal sclerosis. Asymmetry has been observed in schizophrenia. Structure The anterior part of the gyrus includes the perirhinal and entorhinal cortices. The term parahippocampal cortex is used to refer to an area that encompasses both the posterior parahippocampal gyrus and the medial portion of the fusiform gyrus. Function Scene recognition The parahippocampal place area (PPA) is a sub-region of the parahippocampal cortex that lies medially in the inferior temporo-occipital cortex. PPA plays an important role in the encoding and recognition of environmental scenes (rather than faces). fMRI studies indicate that this region of the brain becomes highly active when human subjects view topograp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gray Matter
Grey matter, or gray matter in American English, is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil (dendrites and unmyelinated axons), glial cells (astrocytes and oligodendrocytes), synapses, and capillaries. Grey matter is distinguished from white matter in that it contains numerous cell bodies and relatively few myelinated axons, while white matter contains relatively few cell bodies and is composed chiefly of long-range myelinated axons. The colour difference arises mainly from the whiteness of myelin. In living tissue, grey matter actually has a very light grey colour with yellowish or pinkish hues, which come from capillary blood vessels and neuronal cell bodies. Structure Grey matter refers to unmyelinated neurons and other cells of the central nervous system. It is present in the brain, brainstem and cerebellum, and present throughout the spinal cord. Grey matter is distributed at the surface of the cerebral hemispheres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amygdala
The amygdala (; : amygdalae or amygdalas; also '; Latin from Greek language, Greek, , ', 'almond', 'tonsil') is a paired nucleus (neuroanatomy), nuclear complex present in the Cerebral hemisphere, cerebral hemispheres of vertebrates. It is considered part of the limbic system. In Primate, primates, it is located lateral and medial, medially within the temporal lobes. It consists of many nuclei, each made up of further subnuclei. The subdivision most commonly made is into the Basolateral amygdala, basolateral, Central nucleus of the amygdala, central, cortical, and medial nuclei together with the intercalated cells of the amygdala, intercalated cell clusters. The amygdala has a primary role in the processing of memory, decision making, decision-making, and emotions, emotional responses (including fear, anxiety, and aggression). The amygdala was first identified and named by Karl Friedrich Burdach in 1822. Structure Thirteen Nucleus (neuroanatomy), nuclei have been identif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfactory Cortex
The olfactory system, is the sensory system used for the sense of smell (olfaction). Olfaction is one of the special senses directly associated with specific organs. Most mammals and reptiles have a main olfactory system and an accessory olfactory system. The main olfactory system detects airborne substances, while the accessory system senses fluid-phase stimuli. The senses of smell and taste (gustatory system) are often referred to together as the chemosensory system, because they both give the brain information about the chemical composition of objects through a process called transduction. Structure Peripheral The peripheral olfactory system consists mainly of the nostrils, ethmoid bone, nasal cavity, and the olfactory epithelium (layers of thin tissue covered in mucus that line the nasal cavity). The primary components of the layers of epithelial tissue are the mucous membranes, olfactory glands, olfactory neurons, and nerve fibers of the olfactory nerves. Odor molecu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cingulate Cortex
The cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the cingulate sulcus. The cingulate cortex is usually considered part of the limbic lobe. It receives inputs from the thalamus and the neocortex, and projects to the entorhinal cortex via the cingulum. It is an integral part of the limbic system, which is involved with emotion formation and processing, learning, and memory. The combination of these three functions makes the cingulate gyrus highly influential in linking motivational outcomes to behavior (e.g. a certain action induced a positive emotional response, which results in learning). This role makes the cingulate cortex highly important in disorders such as depression and schizophrenia. It also plays a role in executive function and respiratory control. Structure Based on cerebral c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. ''Psychology''.sec. 3.20 Its various components support a variety of functions including emotion, behavior, long-term memory, and olfaction. The limbic system is involved in lower order emotional processing of input from sensory systems and consists of the amygdala, mammillary bodies, stria medullaris, central gray and dorsal and ventral nuclei of Gudden. This processed information is often relayed to a collection of structures from the telencephalon, diencephalon, and mesencephalon, including the prefrontal cortex, cingulate gyrus, limbic thalamus, hippocampus including the parahippocampal gyrus and subiculum, nucleus accumbens (limbic striatum), anterior hypothalamus, ventral tegmental area, midbrain raphe nuclei, habenular commi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paul Broca
Pierre Paul Broca (, also , , ; 28 June 1824 – 9 July 1880) was a French physician, anatomist and anthropologist. He is best known for his research on Broca's area, a region of the frontal lobe that is named after him. Broca's area is involved with language. His work revealed that the brains of patients with aphasia contained lesions in a particular part of the cortex, in the left frontal region. This was the first anatomical proof of localization of brain function. Broca's work contributed to the development of physical anthropology, advancing the science of anthropometry, and craniometry, in particular, the now-discredited practice of determining intelligence. He was engaged in comparative anatomy of primates and humans and proposed that Negroes were an intermediate form between apes and Europeans. He saw each racial group as its own species and believed racial mixing eventually led to sterility. Biography Paul Broca was born on 28 June 1824 in Sainte-Foy-la-Grande, G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limbic Lobe
The limbic lobe is an arc-shaped cortical region of the limbic system, on the medial surface of each cerebral hemisphere of the mammalian brain, consisting of parts of the frontal, parietal and temporal lobes. The term is ambiguous, with some authors including the paraterminal gyrus, the subcallosal area, the cingulate gyrus, the parahippocampal gyrus, the dentate gyrus, the hippocampus and the subiculum; History Broca named the limbic lobe in 1878, identifying it with the cingulate and parahippocampal gyri, and associating it with the sense of smell - Treviranus having earlier noted that, between species, the size of the parahippocampal gyrus varies with the size of the olfactory nerve. In 1937, Papez theorized that a neural circuit (the Papez circuit) including the hippocampal formation and the cingulate gyrus constitutes the neural substrate of emotional behavior, and Klüver and Bucy reported that, in monkeys, resection involving the hippocampal formation and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midbrain
The midbrain or mesencephalon is the uppermost portion of the brainstem connecting the diencephalon and cerebrum with the pons. It consists of the cerebral peduncles, tegmentum, and tectum. It is functionally associated with vision, hearing, motor control, sleep and wakefulness, arousal (alertness), and temperature regulation.Breedlove, Watson, & Rosenzweig. Biological Psychology, 6th Edition, 2010, pp. 45-46 The name ''mesencephalon'' comes from the Greek ''mesos'', "middle", and ''enkephalos'', "brain". Structure The midbrain is the shortest segment of the brainstem, measuring less than 2cm in length. It is situated mostly in the posterior cranial fossa, with its superior part extending above the tentorial notch. The principal regions of the midbrain are the tectum, the cerebral aqueduct, tegmentum, and the cerebral peduncles. Rostral and caudal, Rostrally the midbrain adjoins the diencephalon (thalamus, hypothalamus, etc.), while Rostral and caudal, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brainstem
The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is continuous with the thalamus of the diencephalon through the tentorial notch, and sometimes the diencephalon is included in the brainstem. The brainstem is very small, making up around only 2.6 percent of the brain's total weight. It has the critical roles of regulating heart and respiratory system, respiratory function, helping to control heart rate and breathing rate. It also provides the main motor and sensory nerve supply to the face and neck via the cranial nerves. Ten pairs of cranial nerves come from the brainstem. Other roles include the regulation of the central nervous system and the body's sleep cycle. It is also of prime importance in the conveyance of motor and sensory pathways from the rest of the brain to the body, and from the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
