Attentional biases are typically measured by reaction time to or time spent looking at an emotional stimulus. Stroop task studies revealed that attentional deficits in depression extend beyond emotional biases. Eye-tracking studies show that depressed individuals spend more time attending to negative stimuli than healthy controls. Conflicting evidence has been found for if attentional tasks are independent of mood state. Despite this promising support, evidence for state-independence is mixed, heritability is mostly unknown, and cosegregation was not supported in relevant studies.