Modern flat outline characters brain neurology psychology concept.Hand drawn Flat little people work-make DNA chain,brain works,idea birth,spin gears in human head.Mind activity-curiosity,study,decide 现代扁平轮廓人物脑神经病学心理学概念。手绘扁平的小人物工作, 制造 dna 链, 大脑工作, 想法诞生, 旋转齿轮在人头上。健康的思想活动思维