 Taken together, the three cases provide examples of detailed manipulations in different sensory modalities, animals, and contents that test for causal sufficiency and necessity across different levels of the sensory processing hierarchy, from early levels (e.g., S1) to mid-levels (MT) and finally to higher levels (lmFG or FFA). Working backwards, the experimental strategy is as follows: Given a perceptual experience with a specific content, one identifies neural correlates that carry equivalent content, say one’s seeing motion, feeling vibration, or parsing words linked to neural correlates processing information about motion, vibrational frequency and word forms. Next, fine-grained manipulations of the neural content are then correlated with related effects on perceptual experience. One issue that remains open is whether in tapping into neural processing by microstimulation, one has simply identified an earlier causal node in the neural processes that generate perceptual experience, there being more informative neural correlates later in the causal pathway. An important question is how one might identify the neural basis of the experience as opposed to its cause.