|
Illusions Of Self-motion
Illusions of self-motion (or "vection") occur when one perceives bodily motion despite no movement taking place. One can experience illusory movements of the whole body or of individual body parts, such as arms or legs. Vestibular illusions The vestibular system is one of the major sources of information about one's own motion. Disorders of the visual system can lead to dizziness, vertigo, and feelings of instability. Vertigo is not associated with illusory self-motion as it does not typically make you feel as though you are moving; however, in a subclass of vertigo known as subjective vertigo one does experience their own motion. People experience themselves being pulled heavily in one direction. There are also specific self-motion illusions that can occur through abnormal stimulation of various parts of the vestibular system, often encountered in aviation. This includes an illusion of inversion, in which one feels like they're tumbling backwards. Through various stimuli, people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vection Diagram
Human senses are not naturally geared for the inflight environment. Pilots may experience disorientation and loss of perspective, creating illusions that range from false horizons to sensory conflict with instrument readings or the misjudging of altitude over water. Vestibular system The vestibular system, which is responsible for the sense of balance in humans, consists of the otolith organs and the semicircular canals. Illusions in aviation are caused when the brain cannot reconcile inputs from the vestibular system and visual system. The three semicircular canals, which recognize accelerations in pitch, yaw, and roll, are stimulated by angular accelerations; while the otolith organs, the saccule and utricle, are stimulated by linear accelerations. Stimulation of the semicircular canals occurs when the movement of the endolymph inside the canals causes movement of the crista ampullaris and the hair cells within them. Stimulation of the otolith organs occurs when grav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Balance Disorder
A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by feelings of giddiness, or wooziness, or having a sensation of movement, spinning, or floating. Balance is the result of several body systems working together: the visual system (eyes), vestibular system (ears) and proprioception (the body's sense of where it is in space). Degeneration or loss of function in any of these systems can lead to balance deficits. Signs and symptoms Cognitive dysfunction (disorientation) may occur with vestibular disorders. Cognitive deficits are not just spatial in nature, but also include non-spatial functions such as object recognition memory. Vestibular dysfunction has been shown to adversely affect processes of attention and increased demands of attention can worsen the postural sway associated with vestibular disorders. Recent MRI studies also show that humans with bilateral vestibular damage (damage to bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetris Effect
The ''Tetris'' effect (also known as ''Tetris'' syndrome) occurs when people devote so much time and attention to an activity that it begins to pattern their thoughts, mental images, and dreams. It takes its name from the video game ''Tetris''. People who have played ''Tetris'' for a prolonged amount of time can find themselves thinking about ways different shapes in the real world can fit together, such as the boxes on a supermarket shelf or the buildings on a street. They may see colored images of pieces falling into place on an invisible layout at the edges of their visual fields or when they close their eyes. They may see such colored, moving images when they are falling asleep, a form of hypnagogic imagery. Those experiencing the effect may feel they are unable to prevent the thoughts, images, or dreams from happening.Stickgold, R., interviewed 30 October 2000 by Norman Swan for ''The Health Report'' on Australia's Radio Nationaltranscript. Retrieved 15 January 2020. A m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spatial Disorientation
Spatial disorientation results in a person being unable to determine their position or relative motion, commonly occurring during periods of challenging visibility, since vision is the dominant sense for orientation. The auditory system, vestibular system (within the inner ear), and proprioceptive system (sensory receptors located in the skin, muscles, tendons and joints) collectively work to coordinate movement with balance, and can also create illusory nonvisual sensations, resulting in spatial disorientation in the absence of strong visual cues. In aviation, spatial disorientation can result in improper perception of the a of the aircraft, referring to the motion of the aircraft (whether turning, ascending or descending). For aviators, proper recognition of aircraft attitude is most critical at night or in poor weather, when there is no visible horizon, and spatial disorientation has led to numerous aviation accidents. Spatial disorientation can occur in other situations where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sense Of Balance
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 In the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seasickness
Motion sickness occurs due to a difference between actual and expected motion. Symptoms commonly include nausea, vomiting, cold sweat, headache, dizziness, tiredness, loss of appetite, and increased salivation. Complications may rarely include dehydration, electrolyte problems, or a lower esophageal tear. The cause of motion sickness is either real or perceived motion. This may include from car travel, air travel, sea travel, space travel, or reality simulation. Risk factors include pregnancy, migraines, and Ménière's disease. The diagnosis is based on symptoms. Treatment may include behavioral measures or medications. Behavioral measures include keeping the head still and focusing on the horizon. Three types of medications are useful: antimuscarinics such as scopolamine, H1 antihistamines such as dimenhydrinate, and amphetamines such as dexamphetamine. Side effects, however, may limit the use of medications. A number of medications used for nausea such as ondansetron are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proprioception
Proprioception ( ), also referred to as kinaesthesia (or kinesthesia), is the sense of self-movement, force, and body position. It is sometimes described as the "sixth sense". Proprioception is mediated by proprioceptors, mechanosensory neurons located within muscles, tendons, and joints. Most animals possess multiple subtypes of proprioceptors, which detect distinct kinematic 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 systems, such as 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 ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ideomotor Phenomenon
The ideomotor phenomenon is a psychological phenomenon wherein a subject makes motions unconsciously. Also called ideomotor response (or ideomotor reflex) and abbreviated to IMR, it is a concept in hypnosis and psychological research. It is derived from the terms "ideo" (idea, or mental representation) and "motor" (muscular action). The phrase is most commonly used in reference to the process whereby a thought or mental image brings about a seemingly "reflexive" or automatic muscular reaction, often of minuscule degree, and potentially outside of the awareness of the subject. As in responses to pain, the body sometimes reacts reflexively with an ideomotor effect to ideas alone without the person consciously deciding to take action. The effects of automatic writing, dowsing, facilitated communication, applied kinesiology, and ouija boards have been attributed to the phenomenon. The associated term "ideo-''dynamic'' response" (or "reflex") applies to a wider domain, and extends to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronic Subjective Dizziness
The term chronic subjective dizziness (CSD) is used to describe a commonly encountered type of dizziness that is not easily categorized into one of several other types, and for which the physical examination is typically normal. Patients with CSD frequently initially suffer a sudden injury of some sort to their vestibular system, the neurologic network that preserves sense of balance. Even after this initial injury has healed, people with CSD usually describe a vague sense of unsteadiness worsened by triggers in their environment such as high places, standing on moving objects, or standing in motion-rich environments like busy streets or crowds. There is a clear indication that anxiety and other mental illnesses play a role in the dizziness symptoms that occur with CSD. However, the condition is categorized as chronic functional vestibular disorder, not as a structural or psychiatric condition. Proposals include renaming it persistent postural-perceptual dizziness (PPPD) which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broken Escalator Phenomenon
The broken escalator phenomenon, also known as the escalator effect and the Walker effect, is the sensation of losing balance, confusion or dizziness reported by some people when stepping onto an escalator which is not working. It is said that there is a brief, odd sensation of imbalance, despite full awareness that the escalator is not going to move. It has been shown that this effect causes people to step inappropriately fast onto a moving platform that is no longer moving, even when this is obvious to the participant. Even though subjects are fully aware that the platform or escalator is not moving now, parts of their brains still act on previous experience gained when it was moving, and so misjudge how to step onto it. Thus, this effect demonstrates the separateness of the declarative and procedural functions of the brain. The broken escalator phenomenon is the result of a locomotor after-effect which replicates the posture adopted when walking onto a moving platform to stab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mal De Debarquement
''Mal de debarquement'' (or ''mal de débarquement'') syndrome (MdDS, or common name disembarkment syndrome) is a neurological condition usually occurring after a cruise, aircraft flight, or other sustained motion event. The phrase "mal de débarquement" is French and translates to "illness of disembarkment". MdDS is typically diagnosed by a neurologist or an Otorhinolaryngology, ear nose and throat specialist when a person reports a persistent rocking, swaying, or bobbing feeling (though they are not necessarily rocking). This usually follows a cruise or other motion experience. Because most vestibular testing proves to be negative, doctors may be baffled as they attempt to diagnose the syndrome. A major diagnostic indicator is that most patients feel better while driving or riding in a car, i.e, while in passive motion. MdDS is unexplained by structural brain or inner ear pathology and most often corresponds with a motion trigger, although it can occur spontaneously. This diffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vestibular System
The vestibular system, in vertebrates, is a sensory system that creates the sense of balance and spatial orientation for the purpose of coordinating movement with balance. Together with the cochlea, a part of the auditory system, it constitutes the labyrinth of the inner ear in most mammals. As movements consist of rotations and translations, the vestibular system comprises two components: the semicircular canals, which indicate rotational movements; and the otoliths, which indicate linear accelerations. The vestibular system sends signals primarily to the neural structures that control eye movement; these provide the anatomical basis of the vestibulo-ocular reflex, which is required for clear vision. Signals are also sent to the muscles that keep an animal upright and in general control posture; these provide the anatomical means required to enable an animal to maintain its desired position in space. The brain uses information from the vestibular system in the head and fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Ideomotor Phenomenon")
