The credits spell Miss Voyich's name "Vohich", although the name appears in print as "Voyich" several times during the film.
In one scene he and his wife are having a candle light dinner and the lighting shows the candles flickering, but the flames on the candles never move.
After the lecture ends at the beginning of the film, Professor Austin is shown erasing the same section of the chalkboard three times.
At one point in the film Professor Austin installs and locks a dead-bolt lock on his door. But when Professor Wilson is shown later touching it, there is no bolt or even a hole for one on the side of the door.