What is the state of a Zen disciples mind prior to a Satori? I have almost finished reading D.T. Suzuki's 'Essay's in Zen Buddhism'. There are many stories of disciples attaining state of Satori (which according to book is akin to Nirvana) when the Zen master does something illogical like twisting the nose or giving an absurd answer to what is asked.

As I am thinking about this it must be that the disciples mind must be in certain state that when the push is given by master it attains Satori. 

Do we have any analytical understanding of this state? Its psychology? Is it a silent persent moment awareness for a long time? Is it something special to the culture and/or mind. Do we have any such examples of monks attaining Satori in present times?
It's a state known as Great Doubt, "dai-gidan" (Japanese) or "dayituan" (Chinese):


  In Ch'an and Zen practice, this represents a highly intense doubt about everything one thinks to be true, including the efficacy of Zen practice itself. (Oxfordreference.com)


For more information, please see the following question: How does the 'Great Doubt' compare to doubt.