What resolves this contention: Whether persistent task-relevant cortical activi…

What resolves this contention: Whether persistent task-relevant cortical activity is held by reciprocal cortico-thalamic excitation or by thalamic gain modulation of intrinsic cortical recurrent dynamics. / Persistent activity is maintained by reciprocal excitation in a closed thalamocortical loop (ALM↔VM/VAL); thalamic inhibition produces near-complete collapse of cortical persistent activity. / Persistent rule representation in PFC is supported not by reciprocal cortico-thalamic excitation per se but by MD-driven amplification of intrinsic PFC connectivity that lets the representation emerge cortically.