The paper presents research into the effects of the use of negations in directives. Three experiments are described that tested the effects of instructions formulated in various ways: direct and negated commands to focus the attention. Indicators of attention focusing that were used include: the correctness of answers to questions about a selection of comic book pages ; the time needed to name the colours of stimulus words and the level of recall of these words after completion of the colour (...) naming task. The results showed that a direct command influenced all indicators of attention focusing. However, a negated command increased the level of recall of details about the comic book pages, as well as the level of key word recall. Both the automatic process that generates the paradoxical effects of negated commands, as well as the controlled process of reasoning, may be responsible for the results of the memory task. (shrink)