射水魚看上去能注意到與背景排列方向不同的物體，科學(xué)家在傳統(tǒng)上把這種特點(diǎn)與哺乳動(dòng)物的大腦聯(lián)系起來,。射水魚是老練的獵手,，具有噴水擊落昆蟲獵物的不尋常的能力。為了確定射水魚是否具有通常與哺乳動(dòng)物視覺皮層有聯(lián)系的視覺選擇性行為,，Ohad Ben-Shahar及其同事首先訓(xùn)練了5條射水魚射擊這些魚的水缸上方顯示昆蟲圖像的液晶顯示器屏幕,。然后，這組科學(xué)家把昆蟲的圖像替換成了有方向或無方向性的背景上的各種位置和方向的黑條,。
通過幾百次試驗(yàn)中的精心控制的一系列實(shí)驗(yàn),，這組科學(xué)家確定了這種魚更多地射擊與背景方向不同的目標(biāo)，而非那些與背景方向類似的物體以及那些在無方向性背景上的物體,。讓人類受試者接受類似刺激的試驗(yàn)提示,，這種魚的“方向性選擇”行為不是依賴于刺激的。這組作者提出,，不論這種魚和人類進(jìn)化出的這種能力來自一個(gè)共同祖先還是各自獨(dú)立進(jìn)化出來的,，該研究顯示了基于方向性的視覺選擇對于高效視覺處理具有普遍性和基礎(chǔ)性。（生物谷Bioon.com）
生物谷推薦英文摘要：
PNAS doi: 10.1073/pnas.1005446107
Orientation saliency without visual cortex and target selection in archer fish
Alik Mokeicheva,b, Ronen Segevb,c,1, and Ohad Ben-Shahara,b,1,2
Our visual attention is attracted by salient stimuli in our environment and affected by primitive features such as orientation, color, and motion. Perceptual saliency due to orientation contrast has been extensively demonstrated in behavioral experiments with humans and other primates and is believed to be facilitated by the functional organization of the primary visual cortex. In behavioral experiments with the archer fish, a proficient hunter with remarkable visual abilities, we found an orientation saliency effect similar to that observed in human subjects. Given the enormous evolutionary distance between humans and archer fish, our findings suggest that orientation-based saliency constitutes a fundamental building block for efficient visual information processing.
