Abstract: Depression is characterized by a negativity bias which is a stable factor of it. The bias reflects enhanced bottom-up responses to affective stimuli, linked to deficits in amygdala and fusiform gyrus function. Alternatively, the bias also reflects impaired top-down cognitive control, linked to deficits in dorsolateral prefrontal cortex and anterior cingulate function. A new hypothesis that the occurrence of depression is caused by interaction of increased activity in affective brain regions and deficits in cognitive-control brain regions was brought forward. To prove the hypothesis, there are still some important questions to be answered, which might be the direction of future studies.

Key words: affective processing, cognitive control, interaction, depression