Like us, zebrafish get hungry. But unlike us they have to engage full-on hunting mode instead of just walking to the fridge to get a snack. By observing a fish brain while it hunts for dinner, Japanese scientists have seen exactly what thoughts look like on the scale of single neurons.
Zebrafish, a common model organism used in biology labs around the world, were held in place while a paramecium snack swam in front of their eye. The scientists were able to genetically engineer the fish’s neurons to glow green when activated, and because the fish are nearly transparent, they could use sophisticated microscopes to map which neurons were firing.
What you’re looking at is the thought pattern of a zebrafish tracking its prey! This is the “thought” that represents “yum yum dinner”. It’s super-important to know that no single neuron holds a thought. Anything that we think or feel exists as a network of neurons firing (or not firing) in a very particular pattern. Understanding that pattern can help us map how an abstract thought is written in “meatspace” so to speak.
The only catch is taking the pattern you see and making it understandable. That fish thought above? That’s the thought, but we have no clue what it means yet. Like following a road map without labels, this trip through the brain is still a confusing one.