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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 mammillary bodies via the mammillothalamic tract and from the subiculum via the fornix. In turn, they project to the cingulate gyrus. 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 cells projecting to the mammillary bodies. These nuclei are considered to be a ... [...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 nucleus of thalamus (''nucleus paraventricularis thalami'') - not to be confused with paraventricular nucleus of hypothalamus * paratenial nucleus (''nucleus parataenialis'') * nucleus reuniens The nucleus reuniens is a region of the thalamic midline nuclear group. In the human brain, it is located in the interthalamic adhesion (''massa intermedia''). The nucleus reuniens receives afferent input from a large number of structures, main ... * rhomboid nucleus (''nucleus commissuralis rhomboidalis'') * subfascicular nucleus (''nucleus subfascicularis'') The 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 paraventr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamus
The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, allowing hub-like exchanges of information. It has several functions, such as the relaying of sensory signals, including motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness. Anatomically, it is a paramedian symmetrical structure of two halves (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 thalamus is a paired structure of gray matter located in the forebrain which is superior to the midbrain, near the center of the brain, with nerve fibers projecting out to th ... [...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 It supports a variety of functions including emotion, behavior, long-term memory, and olfaction. Emotional life is largely housed in the limbic system, and it critically aids the formation of memories. With a primordial structure, the limbic system is involved in lower order emotional processing of input from sensory systems and consists of the amygdaloid nuclear complex ( 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 ... [...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, values, attitudes, and preferences. The ability to learn is possessed by humans, animals, and some 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 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 in terms of an embryo's need for both interaction with, and freedom within its environment within the womb.) 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, neurop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alertness
Alertness is the state of active attention by high sensory awareness such as being watchful and prompt to meet danger or emergency, or being quick to perceive and act. It is related for psychology . A lack of alertness is a symptom of a number of conditions, including narcolepsy, attention deficit disorder, chronic fatigue syndrome, depression, Addison's disease, or sleep deprivation. Pronounced lack of alertness can be graded as an altered level of consciousness. The word is formed from "alert", which comes from the Italian "all'erta" (on the watch, literally, on the height; 1618) Physiological aspects People who have to be alert during their jobs, such as air traffic controllers or pilots, often face challenges maintaining their alertness. Research shows that for people "...engaged in attention-intensive and monotonous tasks, retaining a constant level of alertness is rare if not impossible." If people employed in safety-related or transportation jobs have lapses in ... [...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. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of allocortex. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The cerebral cortex is part of the brain responsible for cognition. 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 cranium. Apart from minimising brain and cranial volume, cortical folding is crucial for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus
The hippocampus (via Latin from Greek , ' seahorse') is a major component of the brain of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. The hippocampus is part of the limbic system, and plays important roles in the consolidation of information from short-term memory to long-term memory, and in spatial memory that enables navigation. The hippocampus is located in the allocortex, with neural projections into the neocortex in humans, as well as primates. The hippocampus, as the medial pallium, is a structure found in all vertebrates. In humans, it contains two main interlocking parts: the hippocampus proper (also called ''Ammon's horn''), and the dentate gyrus. In Alzheimer's disease (and other forms of dementia), the hippocampus is one of the first regions of the brain to suffer damage; short-term memory loss and disorientation are included among the early symptoms. Damage to the hippocampus can also result ... [...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. 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. Etymology The term ''cingu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fornix (neuroanatomy)
The fornix (from lat, fornix, lit=arch) 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subiculum
The subiculum (Latin for "support") is the most inferior component of the hippocampal formation. It lies between the entorhinal cortex and the CA1 subfield of the hippocampus proper. The subicular complex comprises a set of related structures including (as well as subiculum proper) 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 It receives input from CA1 and entorhinal cortical layer III pyramidal neurons and is the main output of the hippocampus. 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 neurons in the subiculum exhibit transitions between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammillothalamic Tract
The mammillothalamic tract (mammillothalamic fasciculus, thalamomammillary fasciculus, bundle of Vicq d’Azyr) arises from cells in both the medial and lateral nuclei of the mammillary body and by fibers that are directly continued from the fornix. The mammillothalamic tract then connects the mammillary body to the dorsal tegmental nuclei, the ventral tegmental nuclei, and the anterior thalamic nuclei. Structure The mammillothalamic tract was first described by the French physician, Félix Vicq d'Azyr, from whom it takes its alternate name (bundle of Vicq d'Azyr). There, axons divide within the gray matter; the coarser branches pass into the anterior nucleus of the thalamus as the ''bundle of Vicq d’Azyr''. The finer branches pass downward as the mammillotegmental ''bundle of Gudden''. The bundle of Vicq d’Azyr spreads fan-like as it terminates in the medial dorsal nucleus. Some fibers pass through the dorsal nucleus to the angular nucleus of the thalamus. ("The term ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
