See me Turn on the ball notice that brush shaped discharges and lightning like streamers of light connect the inside sphere and the outside surface of the ball. At low currents the discharge spreads wide, at higher currents it collects into streamers. A flowing electric current makes magnetic fields. The magnetic fields in turn exert forces on the current pushing it together. Touch me Touch the ball with your hand, notice that your hand influences the pattern of the discharge.
Different people have different sensitivities for detecting current.
However if you cannot feel the current it is probably less than 10 microamps. Place a coin on top of the ball, or a piece of aluminum foil. Bring your hand near the coin. Notice the short blue sparks between your finger and the coin. If you cannot feel the current with your fingertip, there are two places on your body that are most sensitive to electric current, your eyeball and the tip of your tongue.