Feeling sort of confident about this but would appreciate feedback criticism –
The dorsal stream evaluates stimuli response in a primarily subtractive manner, but builds information in an additive manner. That is, when “learning” it creates maps of information then generates the proper data by subtracting the difference between maps.
The ventral stream evaluates stimuli in a primarily additive manner, but stores information in a primarily subtractive manner. Compared to the dorsal stream it starts comparison from a single well defined engram and finds and matches engrams against data globally rather.
Examples of this are in the dorsal stream, a “ball” is a map of many type of balls, and it requires additional maps “Red”, “bouncy” to refine to a specific ball. In the ventral stream, it starts with a specific representation of a ball “My football” and finds things similar to “my football” with a small amount of variance.
When working together, our fast ventral stream can offer up a very dense “map” to search our dorsal stream with, and the dorsal stream offers up a way to inject similarity to ventral stream results.
Research point – Can stimulating dorsal stream structures increase associative flexibility? Can stimulating subcortical ventral stream structures decrease recall speed?