Read the following article and select the best answer. Article: Research at the University of Liverpool, UK, has found that Shakespeare's language stimulates positive brain activity. Shakespeare uses a linguistic technique known as functional change that involves, for example, using a noun to serve as a verb.Researchers found that this technique allows the brain to understand what a word means before it understands the function of the word within a sentence.This process causes a sudden peak in brain activity and forces the brain to work backwards in order to fully understand what Shakespeare is trying to say. Professor Philip Davis, from the university's School of English, said: "The brain reacts to reading a phrase such as 'he godded me' from the tragedy of Coriolanus, in a similar way to putting a jigsaw puzzle together.If it is easy to see which pieces fit together you become bored of the game.But if the pieces don't appear to fit, when we know they should, the brain becomes excited.By throwing irregular words into seemingly normal sentences, Shakespeare surprises the brain in a manner that produces a sudden burst of activity -- a sense of drama created out of the simplest of things." Experts believe that this heightened brain activity may be one of the reasons why Shakespeare's plays have such a dramatic impact on their readers. Professor Neil Roberts, from the university's Magnetic Resonance and Image Analysis Research Center, and Professor Davis, together with Dr Guillaune Thierry, from the University of Wales, UK, monitored 20 participants using an electroencephalogram (EEG) as they read selected lines from Shakespeare's plays. "The brain signal is relatively stable when we understand the meaning of a word but when the word changes the grammar of the whole sentence, brain readings suddenly peak.The brain is then forced to retrace its thinking process in order to understand what it is supposed to make of this unusual word," explains Professor Roberts. Question: Based on the research, Shakespeare's plays have a great effect on their reader lies in _ . - language used in plays - characters showed in works - brain activity increased in reading - thinking process when writing
A:
brain activity increased in reading