This anomaly emits radiation at the same freqencies as some brainwave patterns. The effect is that a mammal entering the anomaly loses all motor function and cannot move any of their muscles voluntarily. The person does not collapse so the muscles can be said to be following the last instructions received from the nervous system. This effect can be overridden by another person giving instructions to the paralysed person. The instructions must be clear and unambiguous, where multiple interpretations of an instruction exist the paralysed person simply doesn't respond.
Insect samples retrieved behaved perfectly normally and seemed unaffected.