“…The IAPS emotional categories were neutral (objects, people, animals and plants), pleasant (from low to high arousal: happy families, babies and puppies, nature scenes, sports and erotica) and unpleasant (from low to high arousal: pollution, loss, disgusting, disease, violence and mutilated bodies). The use of different IAPS pictures as backgrounds, varying in valence and arousal, served as the affective bases of comparison during the evaluation of the target pictures, thus anchoring the emotional rating scales ( 20 , 24 , 25 ) . This standard procedure provides valid between-group ratings, as previously noted ( 20 , 25 , 26 , 48 ) .…”