Identifying a subset of fear-evoking pictures from the IAPS on the basis of dimensional and categorical ratings for a German sample

Background and objectives: The International Affective Picture System (IAPS) is a set of colour photographs depicting a wide range of subject matters. The pictures, which are widely used in research on emotions, are commonly described in terms of the dimensions of valence, arousal and dominance. Little is known, however, about discrete emotions that the pictures evoke. Our aim was to collect dimensional and categorical ratings from a German sample for a subset of IAPS pictures and to identify a set of fear-evoking pictures. Methods: 191 participants (95 female, 96 male, mean age 23.6 years) rated 298 IAPS pictures regarding valence, arousal and the evoked emotion. Results: 64 fear-evoking pictures were identified. Sex differences for categorical and dimensional ratings were found for a considerable number of pictures, as well as differences from the US norms. Conclusions: These differences underscore the necessity of using country-specific and sex-specific norms when selecting stimuli. A detailed table with categorical and dimensional ratings for each picture is provided. (C) 2011 Elsevier Ltd. All rights reserved.