CAMK4 and Menkes disease: Using conditional CaMKIV knock-down, we found that decreasing CaMKIV protein levels during the critical period did not alter intrinsic excitability or mEPSC amplitude or frequency in excitatory neurons in layer (L)2/3 or L4 of monocular V1 (V1m), nor did it affect the homeostatic response of pyramidal neurons in V1m or binocular V1 (V1b) to MD.