I suppose it's possible that this is meant to be, but when I've been affected by neurotoxin (dune scorpion), attacks from already played creatures are no longer being registered. There is no shield, they are not frozen -- even new creatures created by mitosis will not produce successful attacks. *New* creatures, played from the hand after the initial infection, will attack.
I read the explanation of neurotoxin, and this effect was not mentioned.