How can cortical neurons looks like rainbow?

What’s the first thing that comes to your mind when talking about cortical neurons? 

I guess anything but an impressionist painting. But looking at colored cortical neurons under a laser scanning confocal microscope (LSCM), you might think what you see a Claude Monet masterpiece that abstractly renders something. 

Credit: Zhao Jinyue, Institute of Zoology, Chinese Academy of Sciences http://english.rpb.ioz.cas.cn

Equipment: Laser scanning confocal microscope (LSCM)

Subject: Colored cortical neurons

Read more: http://english.ioz.cas.cn/rh/rd/200907/t20090713_23065.html