Pot-head with brain cactus

Pothead with brain cactus, 4

A new take on my old sight gag, that would’ve worked better if I could’ve found a better specimen of (what I believe to be) Mammillaria elongata monstrosus. Mom’s got one, too, and both hers and mine have, for whatever reasons, stopped growing in their curlicue “brain” fashion and started sending out straight tubercles. I don’t know if that’s a normal part of the plant’s life cycle and/or if there’s something we could be doing to prevent it, but whatever the cause, as you can see, it rather spoils the “brain” effect.