At the beginning of the play, both Betty Parris and Ruth Putnam are believed to be under spells as they lie incapacitated in their beds. The Salem doctors do not know the cause of their mysterious illnesses and believe that they have been bewitched, which is why Reverand Parris ends up having Reverend Hale from Beverly to investigate. In court, Abigail and her followers scream, faint, and howl in order to convince the court officials that they are being attacked by the accused person's malevolent spirit.

In act two, Abigail stabs herself in the stomach with a needle and accuses Elizabeth Proctor of attempting to murder her. When Ezekiel Cheever arrives with a warrant for Elizabeth's arrest, they discover a poppet with a needle in its stomach in John's home. The poppet being used as evidence against Elizabeth indicates that the citizens of Salem believe that witches are capable of using voodoo dolls to harm others. Martha Corey is also accused of casting a spell on Walcott's pigs and Rebecca Nurse is charged with murdering Mrs. Putnam's infants. In act three, Abigail and her followers act like Mary Warren's spirit, which is in the form of a bird, is going to attack them and the officials believe the girls. Overall, the symptoms of witchcraft depicted throughout the play involve people being incapacitated, physically harmed, and suffering from audible and visible hallucinations.

In Act I, Scene i, Betty Parris and Ruth Putnam are both unable to wake: 

ABIGAIL: Yes, Uncle. (He goes out with Putnam.) How is Ruth sick?
MERCY: It’s weirdish, I know not—she seems to walk like a dead one since last night.

Abigail attributes their inability to wake to excessive fright as a result of Reverend Parris catching them dancing in the woods around a pot with frogs in it.  They had convinced the Parris' slave, Tituba, to help them cast a spell on Elizabeth Proctor so that John Proctor would leave her for Abigail. 

In Act I, Scene i Betty also tries to fly out the window and she screams when she hears people praying in the Parris home.