The "emotional Stroop task" is the most-used psychological test in evaluating our emotional state. Participants are shown a number of words and asked to name the colors in which they are printed. In general, it takes people longer to identify the colors of negative words like "terrorism" than of neutral words like "table." The trend is particularly pronounced in people with emotional disorders, like depression or anxiety.
There are two general explanations offered. One is that negative words are more distracting, and the other is that they are more threatening. According to both theories, the result is that fewer mental resources are available to identify the ink colors.