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No Picture. When an octopus is blinded by having its optic nerves cut, it still has the delicate touch organs in its eight arms, but it cannot distinguish the shape or size of an object that it touches. All that it can feel is local roughness. The human brain gathers reports from many touch sensors, puts them together and builds up a picture of the object touched. The octopus brain cannot do this, even when several arms are touching the same object. Apparently its central intelligence does not even know clearly where its arms are. In other words, while the octopus is still likely to grab hold of anything that comes close, its brain may have only a vague notion about what that anything may be. This may be of small comfort to the victim.