These aren't "histological details". Histology is done on dead tissue, whereas these researchers are imaging neurons in living animals and are seeing cells sprout new connections when animals learn. This was suspected, but it's quite another thing to see it happening before your eyes. The whole point of science is to test things you suspect; I don't understand your problem with this notion.
It's quite possible and very productive to study "complex mind processes" using in vivo imaging and elecrophysiology techniques. These approaches won't tell you what it feels like for the subject to perceive the world, for that you need literature, poetry, and art, but it's doing a pretty good job in helping us understand the mechanics through which the brain deconstructs sensory information and how it uses this information to make decisions and create memories.
If all else fails, lower your standards.