|
Neuroscience And Sexual Orientation
Sexual orientation is an enduring pattern of romantic or sexual attraction (or a combination of these) to persons of the opposite sex or gender, the same sex or gender, or to both sexes or more than one gender, or none of the aforementioned at all. The ultimate causes and mechanisms of sexual orientation development in humans remain unclear and many theories are speculative and controversial. However, advances in neuroscience explain and illustrate characteristics linked to sexual orientation. Studies have explored structural neural-correlates, functional and/or cognitive relationships, and developmental theories relating to sexual orientation in humans. Developmental neurobiology Many theories concerning the development of sexual orientation involve fetal neural development, with proposed models illustrating prenatal hormone exposure, maternal immunity, and developmental instability. Other proposed factors include genetic control of sexual orientation. No conclusive evidence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Orientation
Sexual orientation is an enduring personal pattern of romantic attraction or sexual attraction (or a combination of these) to persons of the opposite sex or gender, the same sex or gender, or to both sexes or more than one gender. Patterns are generally categorized under heterosexuality, homosexuality, and bisexuality, while asexuality (experiencing no sexual attraction to others) is sometimes identified as the fourth category. These categories are aspects of the more nuanced nature of sexual identity and terminology. For example, people may use other labels, such as '' pansexual'' or '' polysexual'', or none at all. According to the American Psychological Association, sexual orientation "also refers to a person's sense of identity based on those attractions, related behaviors, and membership in a community of others who share those attractions". ''Androphilia'' and ''gynephilia'' are terms used in behavioral science to describe sexual orientation as an alternative to a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethylstilbestrol
Diethylstilbestrol (DES), also known as stilbestrol or stilboestrol, is a nonsteroidal estrogen medication, which is presently rarely used. In the past, it was widely used for a variety of indications, including pregnancy support for those with a history of recurrent miscarriage, hormone therapy for menopausal symptoms and estrogen deficiency, treatment of prostate cancer and breast cancer, and other uses. By 2007, it was only used in the treatment of prostate cancer and breast cancer. In 2011, Hoover and colleagues reported adverse reproductive health outcomes linked to DES including infertility, miscarriage, ectopic pregnancy, preeclampsia, preterm birth, stillbirth, infant death, menopause prior to age 45, breast cancer, cervical cancer, and vaginal cancer. While most commonly taken by mouth, DES was available for use by other routes as well, for instance, vaginal, topical, and by injection. DES is an estrogen, or an agonist of the estrogen receptors, the biologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Putamen
The putamen (; from Latin, meaning "nutshell") is a subcortical nucleus (neuroanatomy), nucleus with a rounded structure, in the basal ganglia nuclear group. It is located at the base of the forebrain and above the midbrain. The putamen and caudate nucleus together form the dorsal striatum. Through various pathways, the putamen is connected to the substantia nigra, the globus pallidus, the claustrum, and the thalamus, in addition to many regions of the cerebral cortex. A primary function of the putamen is to regulate movements at various stages such as in preparation and execution; and to influence various types of learning. It employs GABA, acetylcholine, and enkephalin to perform its functions. The putamen also plays a role in neurodegenerative diseases, such as Parkinson's disease. History The word "putamen" is from Latin, referring to that which "falls off in pruning", from "putare", meaning "to prune, to think, or to consider". Most MRI research was focused broadly on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hippocampus
The hippocampus (: hippocampi; via Latin from Ancient Greek, Greek , 'seahorse'), also hippocampus proper, is a major component of the brain of humans and many other vertebrates. In the human brain the hippocampus, the dentate gyrus, and the subiculum are components of the hippocampal formation located in the limbic system. The hippocampus plays important roles in the Memory consolidation, consolidation of information from short-term memory to long-term memory, and in spatial memory that enables Navigation#Navigation in spatial cognition, navigation. In humans, and other primates the hippocampus is located in the archicortex, one of the three regions of allocortex, in each cerebral hemisphere, hemisphere with direct neural projections to, and reciprocal indirect projections from the neocortex. The hippocampus, as the medial pallium, is a structure found in all vertebrates. In Alzheimer's disease (and other forms of dementia), the hippocampus is one of the first regions of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temporal Lobe
The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain. The temporal lobe is involved in processing sensory input into derived meanings for the appropriate retention of visual memory, language comprehension, and emotion association. ''Temporal'' refers to the head's temples. Structure The temporal lobe consists of structures that are vital for declarative or long-term memory. Declarative (denotative) or explicit memory is conscious memory divided into semantic memory (facts) and episodic memory (events). The medial temporal lobe structures are critical for long-term memory, and include the hippocampal formation, perirhinal cortex, parahippocampal, and entorhinal neocortical regions. The hippocampus is critical for memory formation, and the surrounding medial temporal cortex is currently theorized to be critical f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corpus Callosum
The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental mammals. It spans part of the longitudinal fissure, connecting the left and right cerebral hemispheres, enabling communication between them. It is the largest white matter structure in the human brain, about in length and consisting of 200–300 million axonal projections. A number of separate nerve tracts, classed as subregions of the corpus callosum, connect different parts of the hemispheres. The main ones are known as the genu, the rostrum, the trunk or body, and the splenium. Structure The corpus callosum forms the floor of the longitudinal fissure that separates the two cerebral hemispheres. Part of the corpus callosum forms the roof of the lateral ventricles. The corpus callosum has four main parts – individual nerv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Occipital Lobe
The occipital lobe is one of the four Lobes of the brain, major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin , 'behind', and , 'head'. The occipital lobe is the Visual perception, visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area, Brodmann area 17, commonly called V1 (visual one). Human V1 is located on the Anatomical terms of location#Left and right (lateral), and medial, medial side of the occipital lobe within the calcarine sulcus; the full extent of V1 often continues onto the cerebral hemisphere#Poles, occipital pole. V1 is often also called striate cortex because it can be identified by a large stripe of myelin, the stria of Gennari. Visually driven regions outside V1 are called Extrastriate, extrastriate cortex. There are many extrastriate regions, and these are specialized for different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Cingulate Cortex
The posterior cingulate cortex (PCC) is the caudal part of the cingulate cortex, located posterior to the anterior cingulate cortex. This is the upper part of the " limbic lobe". The cingulate cortex is made up of an area around the midline of the brain. Surrounding areas include the retrosplenial cortex and the precuneus. Cytoarchitectonically the posterior cingulate cortex is associated with Brodmann areas 23 and 31. The PCC forms a central node in the default mode network of the brain. It has been shown to communicate with various brain networks simultaneously and is involved in diverse functions. Along with the precuneus, the PCC has been implicated as a neural substrate for human awareness in numerous studies of both the anesthetized and vegetative (coma) states. Imaging studies indicate a prominent role for the PCC in pain and episodic memory retrieval. Increased size of the ventral PCC is related to a decline in working memory performance. The PCC has also been str ... [...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] |
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] |
Neuroimaging
Neuroimaging is the use of quantitative (computational) techniques to study the neuroanatomy, structure and function of the central nervous system, developed as an objective way of scientifically studying the healthy human brain in a non-invasive manner. Increasingly it is also being used for quantitative research studies of brain disease and psychiatric illness. Neuroimaging is highly multidisciplinary involving neuroscience, computer science, psychology and statistics, and is not a medical specialty. Neuroimaging is sometimes confused with neuroradiology. Neuroradiology is a medical specialty that uses non-statistical brain imaging in a clinical setting, practiced by radiologists who are medical practitioners. Neuroradiology primarily focuses on recognizing brain lesions, such as vascular diseases, strokes, tumors, and inflammatory diseases. In contrast to neuroimaging, neuroradiology is qualitative (based on subjective impressions and extensive clinical training) but sometime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
