The Status Difference And Neural Basis Of The Attentional Blink Task

The attentional blink(AB)effect is a kind of temporal attention impaired,which is the detection of the second target(T2)after the first one(T1)with an interval of 200~500 ms usually is impaired in a stream of rapid serial visual stimuli(RSVP).As a temporal recognition disability,the AB has been focusing by a lot of researchers in last 20 years.In the study processing of the AB effect,the effect of T1 and distraction stimulates on T2 process has been explained by many behavioral studies,and the theories about the AB usually divides to(1)capacity-based models and(2)distractor-based models.Some theoretical model based on the cognitive capacity such as two-stages model;interference theory;eSTST model.According to the view of the capacity-based models,the reason why T2 failed to be reported is that the capacity-limited central mechanisms are unavailable to consolidate T2.Since these mechanisms are engaged in consolidation of T1,consolidation of T2 has to wait,which makes the representation of T2 decays and become more susceptible,that result in the failure of report of T2.However,in accordance with distractor-based models,the AB as a result of distractors presented during the consolidation of T1,these models highlight the importance of the distraction in the AB,proposing that the sensory input filter is changed by distraction is the reason of the AB.However,in the research about the AB,researchers found that the extra task,such as listing music or paying attention to unrelated stimulus during the task,in the AB task could improve the performance.Based on these facts,researchers proposed the AB is due to the special attention state,rather the limitation of the cognitive capacity.Meanwhile,some researchers also pointed that although the difficulty of the T2 recognition in the AB task,the participator also report T2 correctly in some trails,it means that the reason of the AB is not a stable cognitive limitation,instead,participators could distribute attention more flexibly to process T2 if the participators in a better attention state.Besides,the research in the neuronal image also pointed,the correct T2 recognition need the transient and flexible connection between the different brain networks in the AB task.According these studies,we proposed that T2 recognition must rely on the special large-scan connectivity mode in the AB task.Benefiting by the development of the neuronal image and the research about the large-scan brain network,our research plan to explore the attention state and related neural activity in the T2 correct recognition in behavioral and brain network level,and more,we hope to investigate the important role of the attention state in the AB task.Study 1 adopted the simultaneous-cognitive-task paradigm to investigate the influence of the extra task in the AB.The participators were required to perform two different cognitive task simultaneously in one trail.Based on the capacity-limitation model,due to the existed of the extra task,the performance of the AB must be worse.But,if the AB performance rely on the diffused attentional state,the performance of the AB might be better because of the extra task.In study 1,we found no negative effect,instead,the better T2 performance was obtained when the participators complete the extra task correctly.The results pointed that the two different tasks were not limited by the cognition capacity in the same trail,the participators could obtain better AB task performance due to the more flexible attention state comes from the correct completion of extra task.Accordingly,in the AB task,the diffused and flexible attention state might play an important role in the T2 recognition.Based on the results in study 1,we plan to go further to investigate the brain connection mode in the correctly performed trails in the AB task.We have pointed in study 1,the better attention state could be advantage to T2 recognition.Accordingly,we use functional MRI to analysis the difference of the large-scan brain network connection mode between the correct trails and wrong trails,hope to find the relationship between the AB and specific brain state at large-scan level.In our results,we found theleft frontal pole,right mid cingulum,left supplemental motor area cortex,bilateral insula and middle frontal gyrus shown higher activation in the right trails.Then,we used these brain area as seed,compared the differences of the connectivity of seed to voxel of brain between the right and wrong trails.And the stronger connect between the left frontal pole and regions included bilateral temporal cortex and left occipital cortex shown in the right trail,and we also found the right middle cingulate cortex have stronger connect with occipital cortex.Besides,we found the left insula shown stronger connect with left precentral gyrus,postcentral gyrus and superior parietal lobule in wrong trails.Accordingly,we proposed that the activation of frontal pole implied the flexible change of attention orient,and the middle frontal gyrus and insula might relate with the bottom-up attention of T2.In the right trails,the participators have more flexible attention state which manifested as the activation in frontal pole to support more balance attention resource between T1 process and T2 detection.Because the attention orient could translate to outside stimulus when T1 processing,the T2 have the chance to be processed by saliency network and ventral attention network.While in the wrong trails,the connectivity between the insula and middle brain regions and parietal regions might implied that the insula engaged the working memory sustain of T1,influenced the bottom-up process of T2.Based on our results,we found the AB task would be influenced by attention state in behavioral level,we add extra task in the AB task,changed the attention state,enhanced of the performance of the AB.Then we used the fMRI to contrast the brain activity and the connection mode of key regions and all brain voxels.We found the activation at frontal pole which implied the more flexible attention orient in right trails,and the activation on insula and middle frontal gyrus implied the T2 might be processed by saliency network and ventral attention network.However,the insula shown stronger connectivity with middle brain regions and parietal regions,we proposed it's related with the T1 working memory.Concluding,based on our results and discussion,we proposed that the influence for T2 was not come from that limited process capacity engaged by T1,instead,the failed reported of T2 was due to the inner-stimulus attention orient.And more,the more flexible translation of attention orient could overcome the influence come from T1.