On Cognitive Characteristics And Neural Mechanisms Of Verbal Fluency In Normal Chinese Children

Objective: The purpose of our research is to study processing brain areas of verbal fluency in Chinese children , to know its neural mechanism, to discuss its realated cognitive characteristics and to analyze the effect of age and gender on verbal fluency in Chinese children and their corresponding neural activities. On this basis, the research futher examines the influence of motor skill training on vebal fluency. The study will enrich the cognitive processing theory, provide the theoretical evidence for the later Chinese neural mechanisms research and be conducive to new means for children's verbal fluency with a very practical value.Methods: Based on the theories of child cognitive development, information processing and cognitive neuroscience, taking Chinese semantic verbal fluency test as a speech task, by means of functional magnetic resonance imaging and other research tools, using Siemens 3T magnetic resonance imaging system as the test equipment , the research selected normal Chinese children from Shanghai and Changzhou, processed the data with the platform of Matlab 2009 through statistical parameter mapping software (SPM8) and acquired the related fMRI data and behavioral data. The study examined neural mechanisms and cognitive characteristics of verbal fluency in Chinese children's , revealed its internal rules.Results and Conclusions: 1. The processing pattern of verbal fluency in Chinese children showed the bilateral brain activation. Implementation of semantic verbal fluency task significantly activated the following brain regions: left inferior frontal gyrus, left superior frontal gyrus, left globus pallidus, left sub-lobar, left thalamus, left parietal lobe precuneus, right posterior lobe of cerebellum, right inferior frontal gyrus, which were related with the processing of working memory, long-term memory, selective attention and slection - inhibition of executive function; 2. The activation pattern of children under the age of 11 years old was of the basic characteristics of Chinese language processing while children over the age of 12 activated more brain regions of the right side. There were significant differences of acivation areas between children with different age, which may demonstrate that older children have better serach strategies and selection capability. The developmental age difference of speech processing reflects the characteristics of transformation of shape and pronunciation of chinese character and strengthening verbal working memory; 3. The right inferior frontal gyrus played an important role in chinese children, while women more strongly activated the left inferior frontal gyrus, which confirmed the point that the advantage showed by women in the language task related with executive function may attribute to more flexible Search strategies; 4. Long-term motor-skill training will change the individual's neural processing of speech patterns. The activation of speech area and motor area showed the characteristics of mutual activation. Processing machanism of Chinese differed from that of alphabetic language and its activation area mainly concentrated in the bilateral inferior frontal cortex, which was the Broca's area. Since the regions of activation are close to the premotor and motor cortex, motor skill training may show more apparent effect on the Chinese processing.