The Relationship Between Creative Thinking And Inter-hemispheric Structural And Functional Connectivity:A Multimodal Brain Imaging Research

Creativity is a uniquely human advanced cognitive function,which usually refers to the ability to create novel and useful products.The relationship between the function of cerebral hemisphere and creativity has long been guessed,and around which there exists lots of"neuromyth?.One of the most famous myth is that the right hemisphere is the"creating brain"-director of art experience and creative thinking-and the left brain is the"brain"of analytical thinking.Recently,accompanied with the development of cognitive neuroscience,a lot of empirical studies have shown that creativity is not the function of a single hemisphere,but involves coordination and cooperation among multiple functional networks at both sides of cerebrum.Under the influence of these evidence,more and more researchers begin to argue that informational communication flexibly and effectively between the two hemispheres plays a significant role in creative activities,and puts forward some hemisphere interaction theory of creativity.Nevertheless,these theories are still largely hypothetical and based on behavioral researches,insight on the relationship between cerebral hemispheric communication and the creativity is still less relatively.There have been some brain imaging studies focusing on it,but the paradigms which adopted were not unified,and sample size is not enough,so that there is lack of consensus about the problem in academic circles.This study pay attention to the influence of information communication between two cerebral hemispheres to the level of individual creativity,both in structural and functional level,and attempts to explain our results in a unified framework.In order to avoid the problem of sample size and different paradigm,study 1 used a large sample multimodal brain image data,concentrated on the neural structure of information exchange between hemispheres-the corpus callosum.Multiply neural characteristics of different callosum sub-areas were extracted and calculated correlation coefficients with measures of creativity in different areas.The results of study 1 show that:there exist significant and robust positive correlation between the verbal creativity and the white matter volume microstructural integrity of white matter and fiber length of body and genu parts of corpus callosum,and this effect on the body is the most significant.For visual creativity,white matter attribute of the corpus callosum have nothing to do with it.This effect shows that visual creativity may need effective communication between both hemispheres,while the visual creativity may prefer to rely on processing of unilateral hemisphere.Fiber tracking analysis proves that the corpus callosum is mainly responsible for both sides of the genu callosum take charge of intermediate the information communication between bilateral medial prefrontal cortex,the hub of the default mode network,and body part of corpus callosum is mainly responsible for connecting bilateral dorsal frontal lobe,sensorimotor area and part of the parietal lobe.In addition,the positive effect between neural attribution of white matter within the scope affected by corpus callosum and verbal creativity has been relatively stable.Study 2 examined when engaged in creative activities,do the exchange of information between two hemispheres has a promoting effect on creativity.In order to achieve this goal,we adopted the classic divergent thinking task?AUT?,presented participants with some common items in scanner and asked them to think about the innovative uses,and recording their brain activity when conceiving novel ideas.Task-based functional connection method was used to build two kinds of measure of the information exchange between two hemispheres-Mirrored Homotopic Connectivity?MHC?and interhemispheric integration.In results,we found that in subjects thinking creatively,MHC of all brain networks is associated significantly with originality of divergent thinking insight task?IT?in addition to the visual network,and the effects for the limbic system and the ventral attention network is the highest and most stable,whereas hemisphere integration index show more average results,where integration of all networks of bilateral hemispheres and originality of IT exists significant correlation.Study 2 further confirm the research hypothesis,and deepen our knowledge of the relationship between creativity and hemispheric communication.Combined the two sub-study we can draw a conclusion that,informational communication between bilateral hemispheres is associated with creative cognitive processing,and this effect is not just limited to the individual function network,but involves the efficient interaction between multiple functional networks between both sides of brain.Using multi-modal brain image data,this study explored on brain structure and brain function level individual the relationship between creativity and cerebral inter-hemispheric communication.Summarizing our results,we can draw the following conclusions:?1?The white matter measures of genu?Genu CC?and the body of corpus callosum?Body CC?were associated with verbal creativity,and this association was different in each mode:the greater the volume,the higher the white matter fiber integrity and the longer the fiber of the Body CC,the higher the verbal creativity of individual,and this correlation might be driven by the degree of fiber myelination of corpus callosum;the greater the volume of the Genu CC,the higher the verbal creativity,which might be driven by low-myelination crisscross fibers,rather than the degree of myelination.?2?The relationship between creativity in different fields and corpus callosum was different.While closely tied to corpus callosum and verbal creativity,the relationship between corpus callosum with figural creativity weakened even disappeared.^[156]When occupying on creative activity,inter-hemispheric synchronicity of all functional networks?except visual network?and inter-hemispheric integration of all networks was positively correlated with originality score of IT,in which the inter-hemispheric synchronicity of the limbic system and the ventral attention network had the most stable effect.Our research made up for some deficiencies of previous researches,proved the association between inter-hemispheric information exchange and creativity,and might help the future exploration to improve individual creativity based on inter-hemispheric communication.