Danger and usefulness are detected early in auditory lexical processing: evidence from electroencephalography

Visual emotionally charged stimuli have been shown to elicit early electrophysiological responses (e.g., Ihssen, Heim, & Keil, 2007; Schupp, Junghöfer, Weike, & Hamm, 2003; Stolarova, Keil, & Moratti, 2006). We presented isolated words to listeners, and observed, using generalized additive modeling, oscillations in the upper part of the delta range, the theta range (Bastiaansen & Hagoort, 2003), and the lower part of the alpha range related to degree of (rated) danger and usefulness (Wurm, 2007) starting around 150 ms and continuing to 350 ms post stimulus onset. A negative deflection in the oscillations tied to danger around 250-300 ms fits well with a similar negativity observed in the same time interval for visual emotion processing. Frequency and competitor effects emerged or reached maximal amplitude later, around or following the uniqueness point. The early effect of danger, long before the words' uniqueness points, is interpreted as evidence for the dual pathway theory of LeDoux (1996).