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Sense Of Self
A sense is a biological system used by an organism for sensation, the process of gathering information about the surroundings through the detection of stimuli. Although, in some cultures, five human senses were traditionally identified as such (namely sight, smell, touch, taste, and hearing), many more are now recognized. Senses used by non-human organisms are even greater in variety and number. During sensation, sense organs collect various stimuli (such as a sound or smell) for transduction, meaning transformation into a form that can be understood by the brain. Sensation and perception are fundamental to nearly every aspect of an organism's cognition, behavior and thought. In organisms, a sensory organ consists of a group of interrelated sensory cells that respond to a specific type of physical stimulus. Via cranial and spinal nerves (nerves of the central and peripheral nervous systems that relay sensory information to and from the brain and body), the different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cranial Nerves
Cranial nerves are the nerves that emerge directly from the brain (including the brainstem), of which there are conventionally considered twelve pairs. Cranial nerves relay information between the brain and parts of the body, primarily to and from regions of the head and neck, including the special senses of Visual perception, vision, taste, Olfaction, smell, and hearing. The cranial nerves emerge from the central nervous system above the level of the Atlas (anatomy), first vertebra of the vertebral column. Each cranial nerve is paired and is present on both sides. There are conventionally twelve pairs of cranial nerves, which are described with Roman numerals I–XII. Some considered there to be thirteen pairs of cranial nerves, including the non-paired cranial nerve zero. The numbering of the cranial nerves is based on the order in which they emerge from the brain and brainstem, from front to back. The terminal nerves (0), olfactory nerves (I) and optic nerves (II) emerge f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equilibrioception
The sense of balance or equilibrioception is the perception of balance and spatial orientation. It helps prevent humans and nonhuman animals from falling over when standing or moving. Equilibrioception is the result of a number of sensory systems working together; the eyes (visual system), the inner ears ( vestibular system), and the body's sense of where it is in space (proprioception) ideally need to be intact. The vestibular system, the region of the inner ear where three semicircular canals converge, works with the visual system to keep objects in focus when the head is moving. This is called the vestibulo-ocular reflex (VOR). The balance system works with the visual and skeletal systems (the muscles and joints and their sensors) to maintain orientation or balance. Visual signals sent to the brain about the body's position in relation to its surroundings are processed by the brain and compared to information from the vestibular and skeletal systems. Vestibular system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Mouth
In human anatomy, the mouth is the first portion of the alimentary canal that receives Human food, food and produces saliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth. In addition to its primary role as the beginning of the digestive system, the mouth also plays a significant role in communication. While primary aspects of the voice are produced in the throat, the tongue, lips, and human mandible, jaw are also needed to produce the range of sounds included in speech. The mouth consists of two regions, the vestibule and the oral cavity proper. The mouth, normally moist, is lined with a mucous membrane, and contains the human teeth, teeth. The lips mark the transition from mucous membrane to human skin, skin, which covers most of the human body, body. Structure Oral cavity The mouth consists of two regions: the vestibule and the oral cavity proper. The vestibule is the area between the teeth, lips and cheeks. The oral cavity is bound ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Nose
The human nose is the first organ of the respiratory system. It is also the principal organ in the olfactory system. The shape of the nose is determined by the nasal bones and the nasal cartilages, including the nasal septum, which separates the nostrils and divides the nasal cavity into two. The nose has an important function in breathing. The nasal mucosa lining the nasal cavity and the paranasal sinuses carries out the necessary conditioning of inhaled air by warming and moistening it. Nasal conchae, shell-like bones in the walls of the cavities, play a major part in this process. Filtering of the air by nasal hair in the nostrils prevents large particles from entering the lungs. Sneezing is a reflex to expel unwanted particles from the nose that irritate the mucosal lining. Sneezing can Transmission (medicine), transmit infections, because aerosols are created in which the Respiratory droplets, droplets can harbour pathogens. Another major function of the nose is olfactio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Skin
The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue (biology), tissue guarding Skeletal muscle, muscles, bones, ligaments and organ (anatomy), internal organs. Human skin is similar to most of the other mammals' skin, and it is very similar to pig skin. Though nearly all human skin is covered with hair follicles, it can appear Nudity#Evolution of hairlessness, hairless. There are two general types of skin: hairy and glabrous skin (hairless). The adjective List of medical roots, suffixes and prefixes#C, ''cutaneous'' literally means "of the skin" (from Latin ''cutis'', skin). Skin plays an important immunity (medical), immunity role in protecting the body against pathogens and excessive transepidermal water loss, water loss. Its other functions are Thermal insulation, insulation, thermoregulation, temperature regulation, sensation, synthesis of vitamin D, and the protection ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Eye
The human eye is a sensory organ in the visual system that reacts to light, visible light allowing eyesight. Other functions include maintaining the circadian rhythm, and Balance (ability), keeping balance. The eye can be considered as a living optics, optical device. It is approximately spherical in shape, with its outer layers, such as the outermost, white part of the eye (the sclera) and one of its inner layers (the pigmented choroid) keeping the eye essentially stray light, light tight except on the eye's optic axis. In order, along the optic axis, the optical components consist of a first lens (the cornea, cornea—the clear part of the eye) that accounts for most of the optical power of the eye and accomplishes most of the Focus (optics), focusing of light from the outside world; then an aperture (the pupil) in a Diaphragm (optics), diaphragm (the Iris (anatomy), iris—the coloured part of the eye) that controls the amount of light entering the interior of the eye; then an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interoception
Interoception is the collection of Sense#Other internal sensations and perceptions, senses providing information to the organism about the internal state of the body. This can be both conscious and subconscious. It encompasses the brain's process of integrating signals relayed from the body into specific subregions—like the brainstem, thalamus, Insular cortex, insula, Primary somatosensory cortex, somatosensory, and anterior cingulate cortex—allowing for a complex and highly accurate representation of the physiological state of the body. This is important for maintaining Homeostasis, homeostatic conditions in the body and, potentially, facilitating self-awareness. Interoceptive signals are projected to the brain via a diversity of neural pathways, in particular from the lamina I of the spinal cord along the spinothalamic pathway and through the projections of the solitary nucleus, that allow for the sensory processing and prediction of internal bodily states. Misrepresentation ... [...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] |
Sensory Cortex
The sensory cortex can refer sometimes to the primary somatosensory cortex, or it can be used as a term for the primary and secondary cortices of the different senses (two cortices each, on left and right hemisphere): the visual cortex on the occipital lobes, the auditory cortex on the temporal lobes, the primary olfactory cortex on the uncus of the piriform region of the temporal lobes, the gustatory cortex on the insular lobe (also referred to as the insular cortex), and the primary somatosensory cortex on the anterior parietal lobes. Just posterior to the primary somatosensory cortex lies the somatosensory association cortex or area, which integrates sensory information from the primary somatosensory cortex (temperature, pressure, etc.) to construct an understanding of the object being felt. Inferior to the frontal lobes are found the olfactory bulbs, which receive sensory input from the olfactory nerves and route those signals throughout the brain. Not all olfactory infor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoreceptor
A thermoreceptor is a non-specialised sense Cutaneous receptor, receptor, or more accurately the receptive portion of a sensory neuron, that codes absolute and relative changes in temperature, primarily within the innocuous range. In the mammalian peripheral nervous system, warmth receptors are thought to be myelin, unmyelinated C-fibres (low conduction velocity), while those responding to cold have both C-fibers and thinly myelinated A delta fibers (faster conduction velocity). The adequate stimulus for a warm receptor is warming, which results in an increase in their action potential discharge rate. Cooling results in a decrease in warm receptor discharge rate. For cold receptors their firing rate increases during cooling and decreases during warming. Some cold receptors also respond with a brief action potential discharge to high temperatures, i.e. typically above 45 °C, and this is known as a paradoxical response to heat . The mechanism responsible for this behavior has no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemoreceptor
A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance ( endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemoreceptor is a neuron, or in the form of a neurotransmitter that can activate a nerve fiber if the chemoreceptor is a specialized cell, such as taste receptors, or an internal peripheral chemoreceptor, such as the carotid bodies. In physiology, a chemoreceptor detects changes in the normal environment, such as an increase in blood levels of carbon dioxide (hypercapnia) or a decrease in blood levels of oxygen (hypoxia), and transmits that information to the central nervous system which engages body responses to restore homeostasis. In bacteria, chemoreceptors are essential in the mediation of chemotaxis. Cellular chemoreceptors In prokaryotes Bacteria utilize complex long helical proteins as chemoreceptors, permitting signals to travel lon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
