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Anterior Nuclei Of Thalamus
The anterior nuclei of thalamus (or anterior nuclear group) are a collection of nuclei at the rostral end of the dorsal thalamus. They comprise the anteromedial, anterodorsal, and anteroventral nuclei. Inputs and outputs The anterior nuclei receive afferents from the hippocampus and subiculum directly via the fornix, and indirectly via the mammillary bodies and mammillothalamic tract (MTT). They send efferent fibers to the cingulate gyrus, limbic, and orbitofrontal cortex. The anterior nuclei of the thalamus display functions pertaining to memory. Persons displaying lesions in the anterior thalamus, preventing input from the pathway involving the hippocampus, mammillary bodies and the MTT, display forms of amnesia, supporting the anterior thalamus's involvement in episodic memory. However, although the hypothalamus projects to both the mammillary bodies and the anterior nuclei of the thalamus, the anterior nuclei receive input from hippocampal cells deep to the pyramidal c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Midline Nuclear Group
The midline nuclear group (or midline thalamic nuclei) is a region of the thalamus consisting of the following nuclei: * Paraventricular thalamus, paraventricular nucleus of thalamus (''nucleus paraventricularis thalami'') - not to be confused with paraventricular nucleus of hypothalamus * paratenial nucleus (''nucleus parataenialis'') * nucleus reuniens (also known as the medioventral nucleus) * rhomboidal nucleus (''nucleus commissuralis rhomboidalis'') * subfascicular nucleus (''nucleus subfascicularis'') The List of regions in the human brain#Thalamus, midline nuclei are often called "nonspecific" in that they project widely to the cortex and elsewhere. This has led to the assumption that they may be involved in general functions such as alerting. However, anatomical connections might suggest more specific functions, with the paraventricular and paratenial nuclei involved in viscero-limbic functions, and the reuniens and rhomboid nuclei involved in multimodal sensory processin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (: thalami; from Greek language, Greek Wikt:θάλαμος, θάλαμος, "chamber") is a large mass of gray matter on the lateral wall of the third ventricle forming the wikt:dorsal, dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, known as the thalamocortical radiations, allowing hub (network science), hub-like exchanges of information. It has several functions, such as the relaying of sensory neuron, sensory and motor neuron, motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, the thalami are paramedian symmetrical structures (left and right), within the vertebrate brain, situated between the cerebral cortex and the midbrain. It forms during embryonic development as the main product of the diencephalon, as first recognized by the Swiss embryologist and anatomist Wilhelm His Sr. in 1893. Anatomy The thalami ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subiculum
The subiculum (Latin for "support") also known as the subicular complex, or subicular cortex, is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 hippocampal subfield. The subicular complex comprises a set of four related structures including the prosubiculum, presubiculum, postsubiculum and parasubiculum. Name The subiculum got its name from Karl Friedrich Burdach in his three-volume work ''Vom Bau und Leben des Gehirns'' (Vol. 2, §199). He originally named it subiculum cornu ammonis and so associated it with the rest of the hippocampal subfields. Structure The subicular complex receives input from CA1 and entorhinal cortical layer III pyramidal neurons and is the main output of the hippocampus proper. The pyramidal neurons send projections to the nucleus accumbens, septal nuclei, prefrontal cortex, lateral hypothalamus, nucleus reuniens, mammillary nuclei, entorhinal cortex and amygdala. The pyramidal neuro ... [...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] |
Episodic Memory
Episodic memory is the memory of everyday events (such as times, location geography, associated emotions, and other contextual information) that can be explicitly stated or conjured. It is the collection of past personal experiences that occurred at particular times and places; for example, the party on one's 7th birthday. Along with semantic memory, it comprises the category of explicit memory, one of the two major divisions of long-term memory (the other being implicit memory). The term "episodic memory" was coined by Endel Tulving in 1972, referring to the distinction between knowing and remembering: ''knowing'' is factual recollection (semantic) whereas ''remembering'' is a feeling that is located in the past (episodic). One of the main components of episodic memory is the process of recollection, which elicits the retrieval of contextual information pertaining to a specific event or experience that has occurred. Tulving seminally defined three key properties of episodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Learning
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, Attitude (psychology), attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and some machine learning, machines; there is also evidence for some kind of learning in certain plants. Some learning is immediate, induced by a single event (e.g. being burned by a Heat, hot stove), but much skill and knowledge accumulate from repeated experiences. The changes induced by learning often last a lifetime, and it is hard to distinguish learned material that seems to be "lost" from that which cannot be retrieved. Human learning starts at birth (it might even start before) and continues until death as a consequence of ongoing interactions between people and their environment. The nature and processes involved in learning are studied in many established fields (including educational psychology, neuropsychology, experimental psycho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alertness
Alertness is a state of active attention characterized by high sensory awareness. Someone who is alert is vigilant and promptly meets danger or emergency, or is quick to perceive and act. Alertness is a psychological and physiological state. Lack of alertness is a symptom of a number of conditions, including narcolepsy, attention deficit hyperactivity disorder, chronic fatigue syndrome, depression, Addison's disease, and sleep deprivation. Pronounced lack of alertness is an altered level of consciousness. States with low levels of alertness include drowsiness. The word is formed from "alert", which comes from the Italian (on the watch, literally: on the height; 1618). Wakefulness refers mainly to differences between the sleep and waking states; vigilance refers to sustained alertness and concentration. Both terms are sometimes used synonymously with alertness. Importance and difficulty People who have to be alert during their jobs, such as air traffic controllers or ... [...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] |
Cingulate Gyrus
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 (anatomy), 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 Major depressive disorder, depression and schizophrenia. It also plays a role in executive function and respirator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammillothalamic Tract
The mammillothalamic tract (MMT) (also mammillary fasciculus, mammillothalamic fasciculus, thalamomammillary fasciculus, bundle of Vicq d'Azyr) is an efferent pathway of the mammillary bodies which project to the anterior nuclei of the thalamus. The mammillothalamic tract is part of the Papez circuit (involved in spatial memory), starting and finishing in the hippocampus.Shah, A., Jhawar, S. S., & Goel, A. (2012). Analysis of the anatomy of the Papez circuit and adjoining limbic system by fiber dissection techniques. rticle Journal of Clinical Neuroscience, 19(2), 289-298. . The fibers of the MMT are heavily myelinated. It arises from the medial and lateral nuclei of the mammillary bodies, and from fibers that are directly continued from the fornix of the hippocampus. It connects the mammillary bodies to the dorsal tegmental nuclei, the ventral tegmental nuclei, and the anterior thalamic nuclei. Structure Axons divide within the gray matter; the thicker fibres form the MT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammillary Bodies
The mammillary bodies also mamillary bodies, are a pair of small round brainstem nuclei. They are located on the undersurface of the brain that, as part of the diencephalon, form part of the limbic system. They are located at the ends of the anterior arches of the fornix. They consist of two groups of nuclei, the medial mammillary nuclei and the lateral mammillary nuclei. Neuroanatomists have often categorized the mammillary bodies as part of the posterior part of hypothalamus. Structure Connections They are connected to other parts of the brain (as shown in the schematic, below left), and act as a relay for impulses coming from the amygdalae and hippocampi, via the mamillothalamic tract to the thalamus. The lateral mammillary nucleus has bidirectional connections with the dorsal tegmental nucleus. The medial mammillary nucleus connects with the ventral tegmental nucleus. Function File:Slide5dd.JPG, Mammillary body Mammillary bodies, and their projections to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fornix (neuroanatomy)
The fornix (from ; : fornices) is a C-shaped bundle of nerve fibers in the brain that acts as the major output tract of the hippocampus. The fornix also carries some afferent fibers to the hippocampus from structures in the diencephalon and basal forebrain. The fornix is part of the limbic system. While its exact function and importance in the physiology of the brain are still not entirely clear, it has been demonstrated in humans that surgical transection—the cutting of the fornix along its body—can cause memory loss. There is some debate over what type of memory is affected by this damage, but it has been found to most closely correlate with recall memory rather than recognition memory. This means that damage to the fornix can cause difficulty in recalling long-term information such as details of past events, but it has little effect on the ability to recognize objects or familiar situations. Structure The fibers begin in the hippocampus on each side of the bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
