Pleasant to aversive: brainwave response to eating chocolate past satiation

Recent neurobiological research has distinguished between the experience of wanting and liking pleasurable or rewarding stimuli, and these differences have been especially helpful in psychopathology research. However, the self-reported discrimination of wanting and liking has been difficult to reliably measure. We sought to examine this distinction using frontal asymmetry with electroencephalography (EEG). We hypothesized that since EEG can reliably measure approach-withdrawal behaviors, it should also measure changes in "wanting" of pleasurable stimuli (Davidson et al., 1990). EEG was recorded while hungry participants ate chocolate until they were past satiation. Participants also reported subjective ratings of: a) how much they liked the current piece (i.e. liking), and b) how much they wanted the next piece (i.e. wanting). No significant EEG difference was found between participants' first and last piece of chocolate for either the wanting or liking conditions.