Valence and arousal norms for Swedish affective words

Valence and arousal has been found to influence memory performance, both independently and in interaction with each other. In order to conduct studies measuring the effect of valence on memory while controlling for arousal, we aimed to develop a validated list of Swedish words that were all rated medium on arousal, while rated neutral or negative on valence. 131 participants rated 50 words each for valence and arousal. In total, 100 words were rated and are presented here together with two measures of how frequently they appear on blogs and newspapers respectively. Emotional events are often better remembered than neutral ones. Emotional events however often differ from neutral ones in many ways and thus it is hard to determine what is the exact mechanism involved in this enhanced memory effect. Compared to neutral events, emotional events are often more unusual, distinctive, arousing and related to important life goals or events. This means that more attention is paid to them at encoding, and that they are thought about and rehearsed in a higher degree than neutral ones (Fox, 2008, pp.195). The emotional value of an item is commonly classified along two dimensions: valence and arousal. An item that is high on valence is positive, pleasant or appetitive, while an item that is low on valence is negative, aversive and results in a defensive response. The arousal dimension describes the intensity of the activation that an item results in (Lang, 2010). Both valence and arousal seem to have independently enhancing effects on memory with a greater effect of arousal (Kensinger & Corkin, 2003). There are also interaction effects between arousal and valence, where the items that are best remembered are those that are both unpleasant and highly arousing (Kaestner & Polich, 2011). The enhanced memory effect of valence and arousal also seem to be based on distinct neural processes (Kensinger, Corkin & Raichle, 2004; Mickley Steinmetz & Kensinger, 2009). Valence and arousal have for example been showed to have different effects on the role of sleep in emotional memory (Kaestner, Wixted & Mednick, 2013) and to affect intentional memory suppression differently in a Think/No Think task (Marx, Marshall & Castro, 2008). Emotional items often differ from neutral ones in both valence and arousal. This present study was conducted in order to create a validated list of Swedish words that were similar in arousal and differed only in valence. The purpose of this was to have a word list to be used in studies measuring the effect of valence on memory while controlling for the effect of arousal. The aim of the study was to create two sets, one with words that were low on valence and medium in arousal, and one with words that were neutral both in valence and arousal.