The author of the article assumes that the monocellular slime mold is not conscious? Why? Because the belief is that consciousness is not possible without neurons. But this belief is however only a belief.
By reading the article one learns that slime mold behaves very much like a conscious intelligent entity and is able to perform almost miracles. For instance, slime molds can communicate their memories (learned skills) to each other by fusing together and separating after that! This brings strongly in mind the theory of morphic fields by Rupert Sheldrake predicting that learning at the level of individual implies learning at the level of population.
No neurons, no brain! Where do the memories (learned behaviors) reside? Magnetic body is my bet. MB would be the intentional agent controlling the behavior of slime mold and even force it to split to pieces, which fuse together later. If this behavior is not intentional what then!
Maybe the fusion of slime molds induces the replication of MBs and thus behaviors. This mechanism would also explain why both pieces (also that without brain) of a split flat worm growing to full flat worm inherit the behaviors of the planaria. A possible test for MB is the existence of an analog of EEG in some frequency range making possible sensory communications to and control by MB.
For a summary of earlier postings see Latest progress in TGD.