不同时相日光下颜色的恒常性

一、前言 在光源光谱成份改变的条件下,我们周围物体的颜色在眼睛看来保持相对不变,称为颜色恒常性。1807年Thomas Young首先描述了颜色恒常性现象,他指出室内不管是由蜡烛的黄光或火焰的红光来照明的,书页纸仍然看来是白色的。Young认为,外界某一表面的颜色外观,并不完全决定于网膜的红、绿、蓝三种感受器的吸收特性,而也依赖于周围其它物体射入眼睛的光通量。此后,E.Hering对颜色恒常性做了实验表演。一般认为颜色恒常性是对环境照明感受性的降低。视觉通道只传递由物体表面所反射的光谱成     

Effects of Refutational Messages,Thought Provocation,and Decision Deadlines on Signing to Donate Organs1

Across three experiments college students were given refutational messages or other treatments encouraging signing drivers' licenses to donate bodily organs in case of accidental death. An attitudinal measure (willingness to sign) predicted observed signing behavior, but relatively weakly. A measure of behavioral expectation to sign or not to sign predicted more strongly. A discussion with family was encouraged, the impact of that discussion also predicted signing but less strongly so. In Study 1 groups given a refutational message signed at no greater rates than a group given a control message. In Study 2 a refutational message group and a group asked to think about donating for 2 min signed at higher rates than a true control group. In Study 3 groups asked to decide whether or not to sign by a certain date and time signed at a higher rate than a refutational message group as in earlier studies. These procedures are recommended for organ donation signing campaigns.