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BackgroundTo investigate hedonic reactivity and the influence of unconscious emotional processes on the low sensitivity to positive reinforcement of food in anorexia nervosa (AN).MethodAN and healthy women were exposed to palatable food pictures just after a subliminal exposure to facial expressions (happy, disgust, fear and neutral faces), either while fasting or after a standardized meal (hungerversussatiety). Both implicit [facial electromyographic (EMG) activity from zygomatic and corrugator muscles, skin conductance, heart rate, and videotaped facial behavior] and explicit (self-reported pleasure and desire) measures of affective processes were recorded.ResultsIn contrast to healthy women, the AN patients did not display objective and subjective indices of pleasure to food pictures when they were in the hunger states. Pleasure to food cues (liking) was more affected than the desire to eat (wanting) in AN patients. Subliminal ‘fear faces’ increased corrugator muscle reactivity to food stimuli in fasting AN patients, as compared to controls.ConclusionsThe results suggest that unconscious fear cues increase the negative appraisal of alimentary stimuli in AN patients and thus contribute to decreased energy intake.

Recent evidence has suggested that the human occipito-temporal region comprises several subregions, each sensitive to a distinct processing level of visual words. To further explore the functional architecture of visual word recognition, we employed a subliminal priming method with functional magnetic resonance imaging (fMRI) during semantic judgments of words presented in two different Japanese scripts, Kanji and Kana. Each target word was preceded by a subliminal presentation of either the same or a different word, and in the same or a different script. Behaviorally, word repetition produced significant priming regardless of whether the words were presented in the same or different script. At the neural level, this cross-script priming was associated with repetition suppression in the left inferior temporal cortex anterior and dorsal to the visual word form area hypothesized for alphabetical writing systems, suggesting that cross-script convergence occurred at a semantic level. fMRI also evidenced a shared visual occipito-temporal activation for words in the two scripts, with slightly more mesial and right-predominant activation for Kanji and with greater occipital activation for Kana. These results thus allow us to separate script-specific and script-independent regions in the posterior temporal lobe, while demonstrating that both can be activated subliminally.

International audience; Lateral shifts in overt attention have been previously shown to modulate reaction times to lateral electrocutaneous stimuli, as well as perception or unpleasantness thresholds. A response bias can play a role in the elicitation of these lateral differences. Therefore, the present experiment aimed at investigating whether eye orientation induces a decision bias in favour of the ipsilateral hemispace. Participants were asked whether or not they suspected subliminal electrocutaneous shocks, whereas no subliminal stimulation was actually delivered. A secondary visual task led participants to direct their eyes ipsi- or contralateral to the stimulated area. Differences between experimental conditions in the amount of subliminal shocks participants acknowledge to receive (number of positive responses) are thought to reflect decision biases. Low and high trait anxiety participants were involved. Results showed an interaction between the eye orientation and the tested hand. The number of positive responses was smaller in right-hand tests with contralateral eye orienting. This effect fits those described previously with real electrocutaneous stimuli. This interaction is related to hemispheric differences in spatial attention. In contrast to thresholds studies, this study failed to replicate that a lateral difference arises in the low but not in the high trait anxiety individuals, suggesting that this interaction was mostly due to the neurosensory processing of the electrocutaneous stimuli.