查看文章

The cholinergic neurotransmitter system has been proposed to be involved in the processing of probabilistic top-down information provided by endogenous cues in location-cueing paradigms. It has been shown that the behavioral and neural effects of a nicotinic cholinergic stimulation resemble the effects obtained by manipulating the validity of the spatial cues: enhancing cortical nicotine levels and decreasing cue validity both reduce the reaction time difference between invalidly and validly cued targets (ie, the ‘validity effect’) as well as neural activity related to attentional reorienting in parietal brain regions. In the present study, we investigated whether the behavioral and neural effects of nicotine in location-cueing paradigms are dependent upon different a priori cue validities. Twenty-four subjects were investigated in a double-blind placebo-controlled between-subject design with functional magnetic resonance …