A Common Parieto-Frontal Network Is Recruited Under Both Low Visibility and High Perceptual Interference Conditions

Abstract

A fundamental property of visual attention is to select targets from interfering distractors. However, attention can also facilitate the detectability of near-threshold items presented in isolation. The extent to which these two perceptually challenging conditions are resolved by the same neural mechanisms is not well known. In the present event-related fMRI experiment, subjects performed a letter identification task under two perceptually challenging conditions; when the luminance contrast of a target letter was reduced (perceptual visibility manipulation) and when the target letter was flanked by distractors (perceptual interference manipulation). Perceptual interference recruited the right parietal and mid-lateral frontal cortex, while perceptual visibility activated these regions bilaterally. The overlap of activated areas between the two perceptual manipulations suggests that a single parieto-frontal network is summoned under both perceptual visibility and interference conditions.

Emotional Automaticity Is a Matter of Timing

“…We hypothesize that this interaction reflects the impact of top-down attentional mechanisms. Specifically, stronger representation of task-relevant information during high-load trials via top-down attention should result in reduced representation of emotional distracter information caused by representational competition (Desimone and Duncan, 1995;Kastner and Ungerleider, 2000;Marois et al, 2004). We believe that the limited temporal resolution of BOLD data results in the contamination of the rapid, automatic amygdala response to emotional stimuli by the slower, attentionally modulated response.…”

Common regions of dorsal anterior cingulate and prefrontal–parietal cortices provide attentional control of distracters varying in emotionality and visibility

“…The control of task-irrelevant distracters on target processing has been consistently associated with the fronto-parietal network (Kastner & Ungerleider, 2000;Marois et al, 2004;Moran & Desimone, 1985) as well as the ACC (Botvinick et al, 2004;Cohen et al, 2000;Kastner & Ungerleider, 2000;Marois et al, 2000;). Previous studies investigating the response to emotional distraction have also identified the recruitment of frontal, parietal and cingulate cortex (Bishop et al, 2004;Blair et al, 2007;Etkin et al, 2006;Mitchell et al 2007;Vuilleumier, et al, 2001).…”

“…It has been suggested that such top-down control is mediated by prefrontal-parietal attention network (Hopfinger et al, 2000;Kastner & Ungerleider, 2000;Luck et al, 1997;Marois et al, 2000Marois et al, ,2004Moran & Desimone, 1985;Reynolds et al, 1999) as well as the anterior cingulate cortex (ACC) (Gitelman et al, 1999;Kastner & Ungerleider, 2000;Marois et al, 2000;Posner & Petersen, 1990). But are these attentional areas engaged independent of distracter type?…”

Functional Magnetic Resonance Imaging Investigation of Overlapping Lateral Occipitotemporal Activations Using Multi-Voxel Pattern Analysis

“…For example, this interpretation has been the favored account of prefrontal brain areas activated by both observed and performed manual actions and, in this case, has been taken as evidence for a "mirror neuron" system in the human brain (Iacoboni et al, 1999). fMRI studies of phonological retrieval (Price and Friston, 1997), multiple-task performance (Jiang and Kanwisher, 2003), empathy (Singer et al, 2004), and visual attention (Wojciulik and Kanwisher, 1999;Marois et al, 2004) have followed similar logic to make claims about cognitive/ neural mechanisms shared across multiple tasks or stimuli. However, a plausible alternative account of the overlap between hMT, LO, and EBA (and perhaps also for overlapping activations in other brain areas) is that commonly activated voxels contain independent neural systems, each coding for a stimulus or task dimension but intermixed at a resolution below that of individual fMRI voxels.…”