Carrasco Marisa, Loula Fani, Ho Yun-Xian
New York University, New York, New York, USA.
Percept Psychophys. 2006 Aug;68(6):1004-12. doi: 10.3758/bf03193361.
In this study, we investigated how spatial resolution and covert attention affect performance in a texture segmentation task in which performance peaks at midperiphery and drops at peripheral and central retinal locations. The central impairment is called the central performance drop (CPD; Kehrer, 1989). It has been established that attending to the target location improves performance in the periphery where resolution is too low for the task, but impairs it at central locations where resolution is too high. This is called the central attention impairment (CAI; Yeshurun & Carrasco, 1998, 2000). We employed a cuing procedure in conjunction with selective adaptation to explore (1) whether the CPD is due to the inhibition of low spatial frequency responses by high spatial frequency responses in central locations, and (2) whether the CAI is due to attention's shifting sensitivity to higher spatial frequencies. We found that adaptation to low spatial frequencies does not change performance in this texture segmentation task. However, adaptation to high spatial frequencies diminishes the CPD and eliminates the CAI. These results indicate that the CPD is primarily due to the dominance of high spatial frequency responses and that covert attention enhances spatial resolution by shifting sensitivity to higher spatial frequencies.
在本研究中，我们探究了空间分辨率和隐蔽注意如何影响纹理分割任务的表现，在该任务中，表现峰值出现在视网膜中周部，而在视网膜周边和中央位置下降。中央视力损伤被称为中央表现下降（CPD；Kehrer，1989）。已经证实，关注目标位置会提高周边区域的表现，在周边区域分辨率对于该任务来说过低，但在分辨率过高的中央位置则会损害表现。这被称为中央注意损伤（CAI；Yeshurun和Carrasco，1998年、2000年）。我们采用了一种提示程序并结合选择性适应，以探究（1）CPD是否是由于中央位置高空间频率反应对低空间频率反应的抑制，以及（2）CAI是否是由于注意对更高空间频率的转移敏感性。我们发现，对低空间频率的适应并不会改变此纹理分割任务中的表现。然而，对高空间频率的适应会减少CPD并消除CAI。这些结果表明，CPD主要是由于高空间频率反应的主导地位，并且隐蔽注意通过将敏感性转移到更高空间频率来提高空间分辨率。
