The importance of subdimensions in SPA memories

[Seanny123]

As @xchoo explained it, integrators work by finding fixed points in the representation space. Neural noise means it's possible to escape these fixed points. This escape/drift is easier in higher dimensions. Consequently, if you want a non-drifty memory in high dimensions, you should use one ensemble per dimension:

    mem = spa.State(vocab, subdimensions=1,
        represent_identity=False, feedback=1, label="mem")