Shared attentional resources for processing visual and chemosensory information

For many years, researchers have argued that we have separate attentional r esources for the processing of information impinging on each of our sensory receptor systems. However, a number of recent studies have demonstrated th e existence of shared attentional resources for the processing of auditory, visual and tactile stimuli. In the present study, we examined whether ther e are also common attentional resources for the processing of chemosensory stimuli. Participants made speeded (left vs. right) footpedal discriminatio n responses to an unpredictable sequence of visual and chemosensory stimuli presented to either nostril. The participants' attention was directed to o ne or the other modality by means of a symbolic auditory cue (high or low t one) at the start of each trial, which predicted the likely modality for th e upcoming target on the majority (80%) of trials. Participants responded m ore rapidly when the target occurred in the expected modality than when it occurred in the unexpected modality, implying the existence of shared atten tional resources for the processing of chemosensory and visual stimuli.