The activation of interactive attentional networks

Bin Xuan, Melissa-Ann Mackie, Alfredo Spagna, Tingting Wu, Yanghua Tian, Patrick R. Hof, Jin Fan
2016 NeuroImage  
Attention can be conceptualized as comprising the functions of alerting, orienting, and executive control. Although the independence of these functions has been demonstrated, the neural mechanisms underlying their interactions remain unclear. Using the revised attention network test and functional magnetic resonance imaging, we examined cortical and subcortical activity related to these attentional functions and their interactions. Results showed that areas in the extended frontoparietal
more » ... (FPN), including dorsolateral prefrontal cortex, frontal eye fields (FEF), areas near and along the intraparietal sulcus, anterior cingulate and anterior insular cortices, basal ganglia, and thalamus were activated across multiple attentional functions. Specifically, the alerting function was associated with activation in the locus coeruleus (LC) in addition to regions in the FPN. The orienting functions were associated with activation in the superior colliculus (SC) and the FEF. The executive control function was mainly associated with activation of the FPN and cerebellum. The interaction effect of alerting by executive control was also associated with activation of the FPN, while the interaction effect of validity by executive control was mainly associated with the activation in the pulvinar. The current findings demonstrate that cortical and specific subcortical areas play a pivotal role in the implementation of attentional functions and underlie their dynamic interactions. gyrus, left precentral gyrus, right precentral and postcentral gyri, right parahippocampal gyrus, left cuneus, right precuneus, right calcarine cortex, and subcortically in bilateral thalamus extending to SC and left caudate nucleus. Moving + engaging was only associated with left red nucleus. The validity effect was associated with activation in parahippocampal gyrus bilaterally, right lingual gyrus, right fusiform gyrus, and other frontal and parietal brain regions including both FEF, in addition to the thalamus bilaterally, right putamen, and left caudate nucleus. The correlation between SC activation and the behavioral disengaging effect was not significant (r = 0.05, p = 0.41, one-tailed). The localization of SC, as shown in the figure, is more toward the pretectal nucluei rather than the tectal nuclei. This may be due to inaccurate co-registration of some subjects resulting in cutting the activation in the tectal nuclei. It is also possible that the activation is in the pretectal nuclei that are related to gaze-shift and eye movement. Activation associated with the flanker conflict effect- Figure 5 shows FPN activation related to the executive control function, including ACC (peaked at right), AI, FEF, IPS, precentral gyrus bilaterally, and right middle and left inferior occipital cortex. Activation was also found in subcortical regions including bilateral thalamus (including pulvinar and extending to SC) and caudate nucleus, and regions in cerebellum including somatomotor regions of the cerebellum and the vermis (see the right bottom panel of Figure 5 ). We did not find activation specifically within the VTA, but in other nearby midbrain structures (see the enlarged section of the axial slice of Figure 5 ). Figure 6 and Table 5 show activity associated with the interaction and conjunction of the alerting and flanker conflict effects. The interaction of alerting by flanker conflict was related to the activation of bilateral inferior and middle frontal gyri, IPS bilaterally, right insula, and subcortical regions of right putamen and regions of the cerebellum ( Figure 6A ). Conjunction analysis revealed that alerting and flanker conflict shared activation in bilateral ACC, bilateral thalamus, right AI, bilateral FEF, bilateral IPS, and regions of the cerebellum ( Figure 6B ). Activation associated with the interaction and conjunction of alerting and flanker conflict effect- Activation associated with the interaction and conjunction of validity and flanker conflict effect-The interaction of validity by flanker conflict was related to the activation of the right AI, right superior frontal gyrus, right postcentral gyrus, and bilateral pulvinar (see Figure 7A and Table 6 ). The validity and flanker conflict conjunction was related to the activation of left thalamus (extending to pulvinar) ( Figure 7B and Table 6 ). Discussion In this study, beyond associating cortical activation with the independent alerting, orienting, and executive control functions as in our previous study (Fan et al., 2005) , we identified cortical and subcortical regions supporting the attentional functions and the interactions among them. These results expand upon previous knowledge about the brain networks involved in implementing attentional functions, and show that the recruitment of areas of the FPN together with subcortical brain regions underlies dynamic interactions of attentional functions to achieve cognitive/attentional control. Xuan et al.
doi:10.1016/j.neuroimage.2016.01.017 pmid:26794640 pmcid:PMC4803523 fatcat:o6i5xcerivfhfol2zobbs7yqli