The visual cortex has arrays of neurons (or neuronal columns?) which detect specific orientations of objects in the visual field.
Scientists could see this because they could push this electrode into the tissue while showing the live animal subject lines of various orientation. What's unclear in the lecture and in this image is whether what they're measuring was a single neuron or the spikes from a handful. Is each of these vertical slices a cortical column?
This pertains to feasibility of bio-based AI/ML modelling because there are many fewer cortical columns (150k) than neurons (20b) in the brain. Still more interested in developing a small component with feedback loops, etc but thought this was interesting.