Hang on there, are you two talking about SPK the band or SPK the terrorist group/ patients' collective? Or did the terrorist group make records as well? I don't know much about SPK the band, but I'm not sure they had any mental patients involved. It's possible they did, of course, but there are two SPKs. Checking wikipedia it transpires that SPK band
worked in a mental home. Well, there you go then, that doesn't make anything clearer.
In fact, more than two -
wiki 1
SPK 'patients' collective' &
SPK band