Shiu L P, Pashler H
University of California, San Diego, La Jolla.
Percept Psychophys. 1992 Nov;52(5):582-8. doi: 10.3758/bf03206720.
The ability of human observers to discriminate the orientation of a pair of straight lines differing by 3 degrees improved with practice. The improvement did not transfer across hemifield or across quadrants within the same hemifield. The practice effect occurred whether or not observers were given feedback. However, orientation discrimination did not improve when observers attended to brightness rather than orientation of the lines. This suggests that cognitive set affects tuning in retinally local orientation channels (perhaps by guiding some form of unsupervised learning mechanism) and that retinotopic feature extraction may not be wholly preattentive.
人类观察者辨别相差3度的一对直线方向的能力会随着练习而提高。这种提高不会在半视野之间转移，也不会在同一半视野内的象限之间转移。无论是否给予观察者反馈，都会出现练习效应。然而，当观察者关注线条的亮度而非方向时，方向辨别能力并未提高。这表明认知定势会影响视网膜局部方向通道的调谐（可能是通过引导某种形式的无监督学习机制），并且视网膜定位特征提取可能并非完全是前注意的。
