What does the word cataleptical mean? How is it relevant to Madeline's situation?

Catalepsy

A condition characterized by lack of response to external stimuli and by muscular rigidity, so that the limbs remain in whatever position they are placed. It is known to occur in a variety of physical and psychological disorders, such as epilepsy and schizophrenia, and can be induced by hypnosis.

http://www.thefreedictionary.com/cataleptic

These symptoms are very similar to the ones exhibited by Madeline in the story.