Annette Taylor asked:
>(1) Why is that a red light is often used in dark light
situations--
>how does it affect the adaptation of rods to low light?
The rods are not very sensitive to long-wavelength light, so they do
not adapt to it much. (This fact about rods also explains the
Purkinje Effect, that shorter wavelengths, such as blue and green,
appear brighter when we are dark adapted.)
>(2) Why is the particular symptom that comes from motion
sickness's
>root of a mismatch between visual and vestibular symptoms one
related
>to the gut primarily, i.e., nausea and vomiting?
Pinker, in "How the Mind Works," describes an interesting explanation
suggested by Michel Treisman. The suggestion is that our brains
evolved in an environment where gravity was very stable. Only with
historically recent things like roller coasters and space travel is
gravity unstable. When there is a mismatch between vision and what the
vestibular senses are saying about the direction of gravity, we
therefore conclude that something is wrong with our nervous system
rather than that gravity has become unstable. A common cause of
nervous system malfunction is poison. And, if you have been poisoned,
an adaptive response is to vomit.
David Kreiner
Professor of Psychology
Central Missouri State University
Warrensburg MO 64093
Email: [EMAIL PROTECTED]
Phone: 660 543-8076
Fax: 660 543-8505
