Jim "The Anvil" Neidhart's wife told emergency personnel the ex-WWE superstar collapsed while appearing to have a seizure early Monday morning ... and slammed his head when he fell to the ground.
Elizabeth Neidhart told investigators Jim was having difficulty sleeping and got out of bed to change the thermostat. But, when Jim went to touch it, he "turned weirdly as if he were about to dance."
"He then fell towards the wall and ground," the investigation report says.
Elizabeth called 911 thinking he was having a seizure since he "suffers from seizures and takes medication for it.