Anything that blocks dopamine receptors can prolong catatonia.

Flour beetles with low dopamine levels play dead more frequently than those with high levels, and anything blocking dopamine receptor sites can lengthen catatonia. But maintaining a death ruse isn’t easy. The performers are constantly gauging their surroundings for cues on when it’s safe to rise. Chickens, for instance, can sense when a predator’s eyes are upon them. Researchers know this because when they used a stuffed hawk in an experiment, their chicken subjects came out of their catatonia quicker when the hawk’s eyes were averted.