In The Crucible, how do suspicion and name-calling among the Salemites contribute to a growing sense of hysteria?

If a person is already suspicious of something or someone, then they are a great deal more willing to respond emotionally and not logically to any news of that event or person.  For example, Mrs. Putnam is already emotional about the deaths of seven of her eight children, and she desperately wants to know the cause.  Despite the fact that some of the children seemed very healthy, they died quickly.  Because she cannot imagine why...

If a person is already suspicious of something or someone, then they are a great deal more willing to respond emotionally and not logically to any news of that event or person.  For example, Mrs. Putnam is already emotional about the deaths of seven of her eight children, and she desperately wants to know the cause.  Despite the fact that some of the children seemed very healthy, they died quickly.  Because she cannot imagine why God would inflict such misfortune on her, she assumes that it must be the work of the Devil, and so she sends her daughter to Tituba to conjure the dead babies' spirits and find out "what person murdered" them.  She is already suspicious of those women who were midwives to her, and so when Tituba accuses one of them, it is all too easy for Mrs. Putnam to believe.  She says, "I knew it!  Goody Osburn were midwife to me three times [....].  My babies always shriveled in her hands!"  In this way, suspicion can lead quickly to hysteria; Mrs. Putnam is too ready to believe the worst, and so she allows her emotions to rule her.

Further, name-calling and accusations heighten emotions and tension among the townspeople and lead to hysteria.  When Giles Corey barges into the court and declares that "Thomas Putnam is reaching out for land," he is essentially calling him a liar.  Immediately, the response is great: "A roaring goes up from the people."  The typically-subdued Puritans seem to lose control.  

Once accusations begin to fly, people have a tendency to fear that they, too, will be accused.  This could lead them to first accuse those people who they suspect might accuse them.  This is what happens with Reverend Parris.  He is so concerned that his enemies will find out that his daughter and niece conjured spirits in the woods, and so he tries to draw attention to qualities that might make others seem suspicious.  Before Giles and John Proctor have a chance to make their case to Danforth, Parris calls them "contentious" and "mischief," respectively.  He accuses them of having ulterior motives when it is really he who does.  All of this only leads to more confusion and heightened emotion.