Psychologists Karen Gasper and Jerry Clore tested people in good and bad moods on their ability to recreate a drawing from memory. They found that happy people concentrated on the general effect, while sad people went for the detail.

When they were shown an ambiguous drawing, happy people were also more likely to remember and redraw it as a familiar object such as a face. Reproductions by unhappy people were less recognisable and less like the original drawing ( Psychological Science, vol 13, p 34).

The results suggest that mood can affect the way people process information—we think globally when we are happy and get hung up on details when we are sad, says Gasper.