The Neural Mechanism Between Remote Association And Close Assocition

Association has been regarded as one of the most complex cognitive processes, and the ability to select the new associations among previously unrelated items is crucial for creative process. Psychological research on association mainly concentrated in the areas of associative priming, Implicit Association Test and Remote associative Test. Developed brain imaging techniques such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) have made it possible for us to record the precise brain activity associated with remote associative processes. However, the aforementioned studies designed the associate task which was suit to long-time brain reach technique. It is undoubtedly an innovation to adopt RAT and TAR-like experimental materials to reveal the activity of the brain. But to reveal the epoch change of remote association within brain in ERP research, the previous paradigm seemed imperfect. Unfortunately, few attempts have been made to link both remote and close association to the underlying brain structures and neural activities up to now.According to Mednick's theory, concepts were associated with differing strengths to one another within a semantic net-work, the level to which a certain concept activates another concept reflected the remoteness of the two conceptual representations. So we introduce a novel task to investigate the time course of remote association processing. Meanwhile, we introduced restrictions association task and open association task to reveal the epoch change of remote association and close association within brain in ERP research.In experiment 1, we employed xiehouyu as experimental materials, which was a traditional form of language. Subjects were presented a series of xiehouyu and were asked to make a choice between "right" and "wrong" of the xiehouyu. For the close association condition the xiehouyu is a metaphor and for the remote association condition the xiehouyu is a pun. The spatiotemporal analysis of brain activation during the execution of remote association task and close association task was investigated by using high-density event-related brain potentials (ERPs). The results revealed that RAT elicited more negative ERP deflections N270 than CAT in the 250-350 time window, possibly reflected that remote association need more attention resources and work harder to integrate the semantic information. Furthermore, in compare with close association task, a greater negativity in the remote association task was induced during 400-800ms, which was possibly related to the storage of information temporarily and the quantity of the information.In experiment 2, Subjects were presented a series of word pairs and asked to think up a new word which belonged to the category of the second word and could be contacted with the first word. For the close association condition, the first word belonged to the category of the second word (e.g., bread-food, a participant's solution: milk), for the remote association condition, the first word did not belong to the category of the second word (e.g., ring-plant, a participant's solution:watermelon). The spatiotemporal analysis of brain activation during the execution of remote association (RA) task and close association (CA) task was investigated by using high-density event-related brain potentials (ERPs). The results revealed that RAT elicited more negative ERP deflections N370 than CAT in the 250-500 time window. Dipole source analysis of difference waves (RA-CA) indicated that the negative components were localized near left prefrontal lobe (BA 6), possibly associated with the integration of semantic information and priming the novel association information. Furthermore, in compare with CA task, a greater negativity in the RA task was induced during 500-900ms, which was possibly related to the controlled association and the establishment of novel association.