question: in biological terms what causes car sickness?
comment: Not a scientist in any way, but I read its line a disconnect between what your mind sees and your body feels. Like your body feels like your staying still but your eyes show that you're moving
passages: A specific type of motion sickness with similar symptoms but a possibly different etiology is space adaptation syndrome (sometimes referred to as space motion sickness).
  
  "Nausea" in Greek means seasickness ("naus" means ship).
  
  Section::::Cause.
  
  There are various theories that attempt to explain the cause of the condition. 
  
  Section::::Cause.:Sensory conflict theory.
   In these cases, motion is sensed by the vestibular system and hence the motion is felt, but no motion or little motion is detected by the visual system, as in terrestrial motion sickness.
  
  Section::::Types.:Motion is felt but not seen.:Carsickness.
   Vomiting is caused when impulses from the chemoreceptor trigger zone (CRTZ) in the brain are sent to the vomiting center in the medulla. Motion sickness specifically occurs when signals to the CRTZ originate from the inner ear: motion is sensed by the fluid of the semicircular canals, which causes overstimulation. The signal travels to the brain's vestibular nuclei, then to the CRTZ, and finally to the vomiting center. 
   A variation of the sensory conflict theory is known as neural mismatch, implying a mismatch occurring between ongoing sensory experience and long-term memory rather than between components of the vestibular and visual systems. This theory emphasizes "the limbic system in the integration of sensory information and long-term memory, in the expression of the symptoms of motion sickness, and the impact of anti-motion-sickness drugs and stress hormones on limbic system function. The limbic system may be the neural mismatch center of the brain."
  
  Section::::Cause.:Defense against perception of poisoning.
   When the vestibular system and the visual system deliver incongruous results, nausea often occurs. When the vestibular system reports no movement but the visual system reports movement, the motion disorientation is often called motion sickness (or seasickness, car sickness, simulation sickness, or airsickness). In the opposite case, such as when a person is in a zero-gravity environment or during a virtual reality session, the disoriented sensation is often called space sickness or space adaptation syndrome. Either of these "sicknesses" usually ceases once the congruity between the two systems is restored.
   According to sensory conflict theory, the cause of terrestrial motion sickness is the opposite of the cause of space motion sickness. The former occurs when one perceives visually that one's surroundings are relatively immobile while the vestibular system reports that one's body is in motion relative to its surroundings. The latter can occur when the visual system perceives that one's surroundings are in motion while the vestibular system reports relative bodily immobility (as in zero gravity.)
  
  Section::::Cause.:Neural mismatch.
   Motion sickness occurs in connection with travel or movement when an incongruity comes about between visually perceived movement and the vestibular system's sense of bodily movement. Most kinds are considered "terrestrial" motion sickness, such as being carsick, airsick, seasick, or sick from reality simulation. Symptoms include dizziness, fatigue, vertigo, depressed appetite, nonspecific malaise, gastrointestinal discomfort, (most commonly) nausea, and nausea-caused vomiting (see Sopite syndrome). If the cause of the nausea is not resolved, the sufferer will usually vomit, but vomiting may not relieve the feeling of weakness and nausea, which means the person might continue to vomit until the underlying cause of the nausea is resolved.
   BULLET::::- Thigmotaxis is the response of an organism to physical contact or to the proximity of a physical discontinuity in the environment (e.g. rats preferring to swim near the edge of a water maze). Codling moth larvae are believed to used thigmotatic sense to locate fruits to feed on.
  
  Section::::Terminology derived from taxis direction.
  
  There are five types of taxes based on the movement of organisms.
   Simulator sickness
  
  Simulator sickness is a subset of motion sickness that is typically experienced by pilots who undergo training for extended periods of time in flight simulators. Due to the spatial limitations imposed on these simulators, perceived discrepancies between the motion of the simulator and that of the vehicle can occur and lead to simulator sickness.
  
  It is similar to motion sickness in many ways, but occurs in simulated environments and can be induced without actual motion. Symptoms of simulator sickness include discomfort, apathy, drowsiness, disorientation, fatigue, vomiting, and many more.
   At present a "fully adequate theory of motion sickness is not presently available" but contemporary sensory conflict theory, referring to "a discontinuity between either visual, proprioceptive, and somatosensory input, or semicircular canal and otolith input", is probably the most thoroughly studied. According to this theory, when the brain presents the mind with two incongruous states of motion; the result is often nausea and other symptoms of disorientation known as motion sickness. Such conditions happen when the vestibular system and the visual system do not present a synchronized and unified representation of one's body and surroundings.
   Research suggests that this is the body's natural way of adjusting to these systems. The bodies of experienced pilots have adapted to different types of motion experienced during actual flight conditions. When placed into a flight simulator, visual and other stimuli cause their bodies to expect the same motions associated with actual flight conditions. But their bodies instead experience the imperfect motion of the simulator, resulting in sickness.
   Section::::Cause.:Nystagmus hypothesis.
   Section::::Types.:Motion seen but not felt.
  
  In these cases, motion is detected by the visual system and hence the motion is seen, but no motion or little motion is sensed by the vestibular system. Motion sickness arising from such situations has been referred to as "visually induced motion sickness" (VIMS).
  
  Section::::Types.:Motion seen but not felt.:Space motion sickness.
   A similar situation can arise for pilots who have long gaps between simulator uses. During simulation training, the body will eventually adapt to the environment to diminish the effects of simulator sickness. However, when long periods of time are spent outside of the simulator, the body is not able to adequately adapt and symptoms will reappear.
   BULLET::::- Nausea subscale is made up of symptoms such as increased salivation, sweating, nausea, stomach awareness, and burping.
  
  BULLET::::- Oculomotor subscale includes symptoms such as fatigue, headache, eyestrain, and difficulty focusing.
  
  BULLET::::- Disorientation subscale is composed of symptoms such as vertigo, dizzy (eyes open), dizzy (eyes closed), and blurred vision.
   A specific form of terrestrial motion sickness, being carsick is quite common and evidenced by disorientation while reading a map, a book, or a small screen during travel. Carsickness results from the sensory conflict arising in the brain from differing sensory inputs. Motion sickness is caused by a conflict between signals arriving in the brain from the inner ear, which forms the base of the vestibular system, the sensory apparatus that deals with movement and balance, and which detects motion mechanically. If someone is looking at a stationary object within a vehicle, such as a magazine, their eyes will inform their brain that what they are viewing is not moving. Their inner ears, however, will contradict this by sensing the motion of the vehicle. Varying theories exist as to cause. The sensory conflict theory notes that the eyes view motion while riding in the moving vehicle while other body sensors sense stillness, creating conflict between the eyes and inner ear. Another suggests the eyes mostly see the interior of the car which is motionless while the vestibular system of the inner ear senses motion as the vehicle goes around corners or over hills and even small bumps. Therefore, the effect is worse when looking down but may be lessened by looking outside of the vehicle.
   Transport tetany
  
  Transport tetany is a disease that occurs in cows and ewes after the stress of prolonged transport in crowded, hot and poorly ventillated vehicles. It is commonly seen in animals in late pregnancy and those transported to slaughter in crowded, hot, and poorly ventillated vehicles. The disease is generally fatal, even with treatment, unless detected early. It is also known as transit tetany, railroad disease, railroad sickness, or staggers.
   Generally, when adverse symptoms are associated with the condition, however, there may be loss of appetite, heartburn, nervous indigestion, constipation, diarrhea, abdominal distention, headache, vertigo, emaciation, and loss of sleep. Any or all of these symptoms may be present. 
   Air sickness is a kind of terrestrial motion sickness induced by certain sensations of air travel. It is a specific form of motion sickness and is considered a normal response in healthy individuals. It is essentially the same as carsickness but occurs in an airplane. An airplane may bank and tilt sharply, and unless passengers are sitting by a window, they are likely to see only the stationary interior of the plane due to the small window sizes and during flights at night. Another factor is that while in flight, the view out of windows may be blocked by clouds, preventing passengers from seeing the moving ground or passing clouds.
   The manufacture of vehicles is resource intensive, and many manufacturers now report on the environmental performance of their factories, including energy usage, waste and water consumption.
  
  The growth in popularity of the car allowed cities to sprawl, therefore encouraging more travel by car resulting in inactivity and obesity, which in turn can lead to increased risk of a variety of diseases.
   BULLET::::- Fatigue, stress and anxiety are some factors that can increase susceptibility to motion sickness of any type.
  
  BULLET::::- The use of alcohol, drugs, and medications may also contribute to airsickness.
  
  BULLET::::- Additionally, airsickness is more common in women (especially during menstruation or pregnancy), young children, and individuals prone to other types of motion sickness.
  
  BULLET::::- Although airsickness is uncommon among experienced pilots, it does occur with some frequency in student pilots.
  
  Section::::Prevention.
  
  Travelers who are susceptible to motion sickness can minimize symptoms by:
   Section::::Types.:Motion that is seen and felt but whose visual and bodily perception is incongruous.
  
  When moving within a rotating reference frame such as in a centrifuge or environment where gravity is simulated with centrifugal force, the coriolis effect causes a sense of motion in the vestibular system that does not match the motion that is seen.
  
  Section::::Treatment.
  
  Many cures and preventatives for motion sickness have been proposed.
  
  Section::::Treatment.:Devices.
   BULLET::::- Magnetotaxis is, strictly speaking, the ability to sense a magnetic field and coordinate movement in response. However, the term is commonly applied to bacteria that contain magnets and are physically rotated by the force of the earth's magnetic field. In this case, the "behaviour" has nothing to do with sensation and the bacteria are more accurately described as "magnetic bacteria".
  
  BULLET::::- Pharotaxis is the movement to a specific location in response to learned or conditioned stimuli, or navigation by means of landmarks.
  
  BULLET::::- Phonotaxis is the movement of an organism in response to sound.
   There are many speculations as to what is the main cause of astasis. A combination of weakness of the triceps surae muscle, peripheral neuropathy, and irregular postural movements are the leading theories thus far. Diabetes, spinal root or spinal cord lesions, and traumas or injuries to the motor cortex of the brain can also cause similar symptoms that are seen in patients with astasis. However, none of these have been proven definite. Many scientists also believe that this is a conversion disorder, in which patients exhibit symptoms without any neurological cause.
  
  Section::::Causes.:Peripheral neuropathy.
   Section::::Types.:Motion is felt but not seen.:Seasickness.
  