Consciousness and cognition
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In the present study, we examined the impact of verbal instruction during extinction of human fear-conditioning. We extended the study of Raes, De Houwer, Verschuere, and De Raedt (2011) by controlling for context conditioning and recording unconditioned stimulus expectancy online in a within-subject design. ⋯ The results demonstrated that both the expectancy of an aversive outcome and conditioned skin conductance were significantly increased for the conditioned stimulus targeted by the instruction. Thus extinction was reversed by the concurrent presence of an alternative cause for the absence of the unconditioned stimulus.
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The ability to select, within the complexity of sensory input, the information most relevant for our purposes is influenced by both internal settings (i.e., top-down control) and salient features of external stimuli (i.e., bottom-up control). We here investigated using fMRI the neural underpinning of the interaction of top-down and bottom-up processes, as well as their effects on extrastriate areas processing visual stimuli in a category-selective fashion. We presented photos of bodies or buildings embedded into frequency-matched visual noise to the subjects. ⋯ Furthermore, the extrastriate body area (EBA) exhibited increased neural activity when attention was directed to bodies. However, the latter effect was found only when stimuli were presented at intermediate saliency levels, thus suggesting a top-down modulation of this region only in the presence of weak bottom-up signals. Taken together, our results highlight the role of the inferior frontal junction and posterior parietal regions in integrating bottom-up and top-down attentional control signals.