Information that has just being introduced into the discourse is called ; whereas, information that is currently in the forefront of the addressee's mind due to the linguistic or situational context is .

1. New information

2. Given Information

Explanation:

New information is the information just being introduced into the discourse.

while given information is information that is on the addressee's mind and this information doesnt need to be introduced by a second speaker.

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

the answer to your question is,

old stone age.

-mabel < 3