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Brainstem Auditory Evoked Response
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] |
Brain
The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for special senses such as visual perception, vision, hearing, and olfaction. Being the most specialized organ, it is responsible for receiving information from the sensory nervous system, processing that information (thought, cognition, and intelligence) and the coordination of motor control (muscle activity and endocrine system). While invertebrate brains arise from paired segmental ganglia (each of which is only responsible for the respective segmentation (biology), body segment) of the ventral nerve cord, vertebrate brains develop axially from the midline dorsal nerve cord as a brain vesicle, vesicular enlargement at the rostral (anatomical term), rostral end of the neural tube, with centralized control over all body segments. All vertebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Face
The face is the front of the head that features the eyes, nose and mouth, and through which animals express many of their emotions. The face is crucial for human identity, and damage such as scarring or developmental deformities may affect the psyche adversely. Structure The front of the human head is called the face. It includes several distinct areas, of which the main features are: *The forehead, comprising the skin beneath the hairline, bordered laterally by the temples and inferiorly by eyebrows and ears *The eyes, sitting in the orbit and protected by eyelids and eyelashes * The distinctive human nose shape, nostrils, and nasal septum *The cheeks, covering the maxilla and mandible (or jaw), the extremity of which is the chin *The mouth, with the upper lip divided by the philtrum, sometimes revealing the teeth Facial appearance is vital for human recognition and communication. Facial muscles in humans allow expression of emotions. The face is itself a highly s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
First Cervical Vertebra
In anatomy, the atlas (C1) is the most superior (first) cervical vertebra of the spine and is located in the neck. The bone is named for Atlas of Greek mythology, just as Atlas bore the weight of the heavens, the first cervical vertebra supports the head. However, the term atlas was first used by the ancient Romans for the seventh cervical vertebra (C7) due to its suitability for supporting burdens. In Greek mythology, Atlas was condemned to bear the weight of the heavens as punishment for rebelling against Zeus. Ancient depictions of Atlas show the globe of the heavens resting at the base of his neck, on C7. Sometime around 1522, anatomists decided to call the first cervical vertebra the atlas. Scholars believe that by switching the designation atlas from the seventh to the first cervical vertebra Renaissance anatomists were commenting that the point of man's burden had shifted from his shoulders to his head—that man's true burden was not a physical load, but rather, his mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Somatosensory System
The somatosensory system, or somatic sensory system is a subset of the sensory nervous system. The main functions of the somatosensory system are the perception of external stimuli, the perception of internal stimuli, and the regulation of body position and balance (proprioception). It is believed to act as a pathway between the different sensory modalities within the body. As of 2024 debate continued on the underlying mechanisms, correctness and validity of the somatosensory system model, and whether it impacts emotions in the body. The somatosensory system has been thought of as having two subdivisions; *one for the detection of mechanosensory information related to touch. Mechanosensory information includes that of light touch, vibration, pressure and tension in the skin. Much of this information belongs to the sense of touch which is a general somatic sense in contrast to the special senses of sight, smell, taste, hearing, and balance. * one for the nociception dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pain
Pain is a distressing feeling often caused by intense or damaging Stimulus (physiology), stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sense, sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage." Pain motivates organisms to withdraw from damaging situations, to protect a damaged body part while it heals, and to avoid similar experiences in the future. Congenital insensitivity to pain may result in reduced life expectancy. Most pain resolves once the noxious stimulus is removed and the body has healed, but it may persist despite removal of the stimulus and apparent healing of the body. Sometimes pain arises in the absence of any detectable stimulus, damage or disease. Pain is the most common reason for physician consultation in most developed countries. It is a major symptom in many medical conditions, and can interfere with a person's quality of life and general fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinothalamic Tract
The spinothalamic tract is a nerve tract in the anterolateral system in the spinal cord. This tract is an ascending sensory pathway to the thalamus. From the ventral posterolateral nucleus in the thalamus, sensory information is relayed upward to the somatosensory cortex of the postcentral gyrus. The spinothalamic tract consists of two adjacent pathways: anterior and lateral. The anterior spinothalamic tract carries information about crude touch. The lateral spinothalamic tract conveys pain and temperature. In the spinal cord, the spinothalamic tract has somatotopic organization. This is the segmental organization of its cervical, thoracic, lumbar, and sacral components, which is arranged from most medial to most lateral respectively. The pathway crosses over ( decussates) at the level of the spinal cord, rather than in the brainstem like the dorsal column-medial lemniscus pathway and lateral corticospinal tract. It is one of the three tracts which make up the anterola ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proprioception
Proprioception ( ) is the sense of self-movement, force, and body position. Proprioception is mediated by proprioceptors, a type of sensory receptor, located within muscles, tendons, and joints. Most animals possess multiple subtypes of proprioceptors, which detect distinct kinesthetic parameters, such as joint position, movement, and load. Although all mobile animals possess proprioceptors, the structure of the sensory organs can vary across species. Proprioceptive signals are transmitted to the central nervous system, where they are integrated with information from other Sensory nervous system, sensory systems, such as Visual perception, the visual system and the vestibular system, to create an overall representation of body position, movement, and acceleration. In many animals, sensory feedback from proprioceptors is essential for stabilizing body posture and coordinating body movement. System overview In vertebrates, limb movement and velocity (muscle length and the rate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutaneous Receptor
A cutaneous receptor is a sensory receptor found in the skin that provides information about temperature, touch (including vibration and pain), spatial orientation,pressure (stretching or squeezing), and metabolic circumstances (including those induced by external chemical substances). The main four types of cutaneous receptors are tactile corpuscles, bulbous corpuscles, Pacinian corpuscles, and Merkel nerve endings, although the latter do not qualify as sensory corpuscles in the narrow sense. Types The sensory receptors in the skin are: *Mechanoreceptors **Bulbous corpuscles (skin stretch) ** Bulboid corpuscles (Cold) **Tactile corpuscles (changes in texture, slow vibrations) ** Pacinian corpuscles (deep pressure, fast vibrations) ** Merkel nerve endings (sustained touch and pressure) ** Free nerve endings *thermoreceptor * nociceptors *chemoreceptors Modalities With the above-mentioned receptor types the skin can sense the modalities touch, pressure, vibration, temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fine Touch
The somatosensory system, or somatic sensory system is a subset of the sensory nervous system. The main functions of the somatosensory system are the perception of external stimuli, the perception of internal stimuli, and the regulation of body position and balance (proprioception). It is believed to act as a pathway between the different sensory modalities within the body. As of 2024 debate continued on the underlying mechanisms, correctness and validity of the somatosensory system model, and whether it impacts emotions in the body. The somatosensory system has been thought of as having two subdivisions; *one for the detection of mechanosensory information related to touch. Mechanosensory information includes that of light touch, vibration, pressure and tension in the skin. Much of this information belongs to the sense of touch which is a general somatic sense in contrast to the special senses of sight, smell, taste, hearing, and balance. * one for the nociception detecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Column-medial Lemniscus Pathway
Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ... * Dorsal consonant, a consonant articulated with the back of the tongue * Dorsal fin, the fin located on the back of a fish or aircraft * Dorsal transcription factor, a maternally synthesized transcription factor {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticospinal Tract
The corticospinal tract is a white matter motor pathway starting at the cerebral cortex that terminates on lower motor neurons and interneurons in the spinal cord, controlling movements of the limbs and trunk. There are more than one million neurons in the corticospinal tract, and they become myelinated usually in the first two years of life. The corticospinal tract is one of the pyramidal tracts, the other being the corticobulbar tract The corticobulbar (or corticonuclear) tract is a two-neuron white matter motor pathway connecting the motor cortex in the cerebral cortex to the Medullary pyramids (brainstem), medullary pyramids, which are part of the brainstem's medulla oblonga .... Anatomy The corticospinal tract originates in several parts of the brain, including not just the motor areas, but also the primary somatosensory cortex and premotor areas. Most of the neurons originate in either the primary motor cortex (precentral gyrus, Brodmann area 4) or the premotor fron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleep Cycle
The sleep cycle is an oscillation between the slow-wave and REM (paradoxical) phases of sleep. It is sometimes called the ultradian sleep cycle, sleep–dream cycle, or REM-NREM cycle, to distinguish it from the circadian alternation between sleep and wakefulness. In humans, this cycle takes 70 to 110 minutes (90 ± 20 minutes). Within the sleep of adults and infants there are cyclic fluctuations between quiet and active sleep. These fluctuations may persist during wakefulness as rest-activity cycles but are less easily discerned. Characteristics Electroencephalography shows the timing of sleep cycles by virtue of the marked distinction in brainwaves manifested during REM and non-REM sleep. Delta wave activity, correlating with slow-wave (deep) sleep, in particular shows regular oscillations throughout a good night's sleep. Secretions of various hormones, including renin, growth hormone, and prolactin, correlate positively with delta-wave activity, while secretion of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
