Chinese gender differences in the cerebral cortex imaging study

　　Title: Chinese gender differences in the cerebral cortex imaging study
　　Authors: Bo Sun
　　Degree-granting units: Shandong University
　　Key words: cerebral cortex;; gender differences;; side of the resistance difference;; magnetic resonance imaging
　　Abstract:
　　The brain is the most important and complex human organ, which dominates the body movement and coordination, and mental activities, maintain and regulate the body's homeostasis (such as breathing, heart rate, endocrine, etc.). Gender differences in brain structure determine its behavior on different: men are good in space and abstract capabilities, while women are Neodymium Magnet more adept at language and memory. Since gender differences in brain structure has been found, has been a hot issue of Brain Research.
　　Some scholars of early application of an autopsy study method first discovered more than the female brain male brain size of about 10%. Since then, studies have found that men and women in the brain gray matter and white matter volume, surface area and thickness of gray matter and the local structure (such as the hippocampus, etc.) vary. However, the methods used or the Institute for the selection of subjects is different, so the results also have contradictory. In addition, a number of specimens studied has its own deficiencies, such as the source of specimen difficult, time consuming, which makes the study of specimens in general is not the number of sample cases; In addition, samples of the measurement error and subjectivity is also larger, which also restricted the sample anatomical research.
　　As the imaging technology and the rapid development of computer technology, application methods of neuroanatomy imaging studies have gradually replaced the traditional autopsy study methods. Neuroimaging anatomy more readily available a large number of clinical image data, and by advanced computer software technology for data processing and analysis, measurement error is small and the artificially high repeatability. However, previous imaging research data, mostly from Western populations, lack of Chinese people's data. About one-fifth of the world's population of ethnic Chinese are a typical representative of the East, the urgent need for the Chinese people the system data collation and analysis, with a view to our neurological research, and the cause of nervous system disorders has laid morphology basis.
　　In this study, the age and gender-matched healthy Chinese young people 3.0T MR image data, through advanced computer software technology and local structure of the whole brain sex differences and differences in analysis of lateral resistance.
　　The study is divided into three parts, summarized as follows:
　　The first part of the Chinese people study gender differences in brain size
　　Chapter: the overall volume of the Chinese gender differences in brain research
　　Objective: Voxel-based methods using high-resolution structural MRI image analysis to examine the overall volume of the Chinese brain sex differences and lateral resistance.
　　Materials and Methods: 69 cases of age-and sex-matched normal right-Chinese young people (male 30, female 39, mean age 23.9 ± 3.4 years), the http://www.everbeenmagnet.com/ application 3.0T GE MRI scanner to scan for AC-PC line baseline scan, using axial 3D T1-weighted fast spoiled gradient echo sequence (Fast Spoiled Gradient-echo, FSPGR), to obtain high-resolution structural MRI brain data. First, the application of FSL software BET (Brain Extraction Tool) Tools to remove the skull and the surrounding non-brain tissue. Then, the application BrainSuite software Partial Volume Classify instruments according to the image signal strength to the brain is divided into gray matter, white matter and cerebrospinal fluid, and then apply FreeSurfer software Compute Volume tools were used to measure gray and white matter voxel number, to obtain the cerebral hemispheres in the original space gray matter and white matter volume. FreeSurfer software using three-dimensional reconstruction of the surface of the brain hemispheres, and then apply ShapeReport tools to measure the surface of the cerebral hemispheres in the original space of the surface area and degree of folding. Through the establishment of minimum deformation target brain model (MDT_69) and the application of the original image to 12-parameter linear affine transformation MDT_69 space, access to each individual's proportion of the value of Space Standardization (Jacobian Value). Then, according to the value of this Jacobian to obtain space for each individual normalized brain hemisphere volume and surface area value value. Finally, the use of standard statistical methods were analyzed before and after the gray and white matter volume, surface area of ​​the cerebral hemispheres and gender differences in the degree of folding and lateral resistance differences.
　　Results:
　　1 Gender differences: the former for Space Standardization, and the whole cerebral hemispheres male gray and white matter volume were significantly larger than females (P <0.05). Space Standardization, men significantly larger than females (P <0.05) for the right side of the gray matter volume, cortical folding degree of the left hemisphere; women was significantly larger than males (P <0.05) for the overall volume of the left hemisphere, the overall volume of the right hemisphere, right side of the white matter volume, surface area of ​​the left hemisphere, right hemisphere surface area.
　　2 side resistance difference: the former for Space Standardization, male and female overall and the left hemisphere gray matter volume was significantly greater than the right (P <0.05), while the female right hemisphere white matter volume was significantly larger than the left (P <0.05). Standardized space, the left was significantly larger than the right (P <0.05) the overall volume of a male hemisphere, male gray matter volume, the overall volume of female hemispheres, women gray matter volume; right side was significantly larger than the left (P <0.05) are female white matter volume; male and female brain hemisphere surface area and degree of folding was no significant difference in lateral resistance (P> 0.05).
　　Conclusion: the whole brain volume, gray and white matter and gray matter volume and surface area are folded there is a certain degree of gender differences, and differences in lateral resistance was seen only in brain volume parameters, these differences may be male and female brain differences in function morphological basis.
　　Chapter II: Chinese, local gray matter volume of brain research on gender differences
　　Objective: Voxel-based approach of the Chinese brain localized gray matter volume differences between gender and side resistance.
　　Materials and Methods: from 69 age-and sex-matched normal right-Chinese young people's high-resolution 3D FSPGR 3.0T MRI sequence data. The use of LONI Brain Parser software structure of the brain of the 54 automatic segmentation of gray matter, and then apply the Compute Volume FreeSurfer software tools were used to measure the number of voxels for each structure, resulting in 54 brain structures and six brain regions (frontal, top lobe, temporal lobe, occipital lobe, insula and cingulate gyrus) gray matter volume in the original space. Then, according to the value of the Jacobian has been obtained for each brain region in the space structure and the gray matter volume normalized value. Finally, the use of statistical methods to analyze brain were gender differences in local gray matter volume differences and lateral resistance.
　　Results:
　　1. The brain gray matter volume analysis:
　　1.1 gender differences: men was significantly larger than females (P <0.05) of brain regions for the left insula, right insula; women was significantly larger than males (P <0.05) of brain regions for the left frontal lobe, right frontal leaves, the left parietal lobe, right parietal lobe.
　　1.2 Side resistance differences: men was significantly greater than the right side of the left (P <0.05) for the temporal lobe of the brain regions and insular cortex; the right side was significantly larger than the left (P <0.05) and parietal brain regions are occipital lobe. Women was significantly greater than the left side of the right (P <0.05) for the temporal lobe of the brain regions and insular cortex; the right side was significantly larger than the left (P <0.05) of the brain are the frontal, parietal, occipital and cingulate gyrus.
　　2.54 Structure of the analysis results
　　2.1 Gender differences: the left was significantly larger than male female (P <0.05) of the structure outside the orbitofrontal gyrus; right side of the men was significantly larger than females (P <0.05) the structure of the suboccipital back. Women than men left significantly (P <0.05) the structure of superior frontal gyrus, middle frontal gyrus, the orbitofrontal back, pillow back, pillow in the back, parahippocampal gyrus, hippocampus, caudate nucleus, shell; the right of women significantly larger than males (P <0.05) the structure of superior frontal gyrus, middle frontal gyrus, precentral gyrus, the orbitofrontal back, top back, precuneus, pillow back wedge leaves, parahippocampal gyrus, caudate nucleus.
　　2.2 Side resistance differences: men was significantly greater than the right side of the left (P <0.05) the structure of the superior frontal gyrus, straight back, precuneus, parahippocampal gyrus, fusiform gyrus; men was significantly greater than the right side of the left side (P <0.05) the structure of the middle frontal gyrus, precentral gyrus, the orbitofrontal back, top back, angular gyrus, occipital gyrus, suboccipital back wedge lobe, caudate nucleus. Women was significantly greater than the left side of the right (P <0.05) the structure of the superior frontal gyrus, straight back, after the central back, precuneus, superior temporal gyrus, inferior temporal gyrus, parahippocampal gyrus, hippocampus, fusiform gyrus, shell; women was significantly greater than the right side of the left (P <0.05) the structure of the middle frontal gyrus, precentral gyrus, the orbitofrontal back, outside the orbitofrontal back, top back, angular gyrus, occipital gyrus, suboccipital back , wedge leaves, lingual gyrus, temporal gyrus, caudate nucleus.
　　Conclusion: Bilateral gray matter volume of the local structure of the female than male-dominated; male and female gray matter volume of the local structure of the resistance to the right side into the more common, and women have significant side of the resistance of the structure than men.
　　Part II: Chinese, gender differences in the thickness of the cerebral cortex of
　　Objective: MRI data using high-resolution three-dimensional structure of the Chinese side of cortical thickness and resistance of gender differences.
　　Materials and Methods: 69 cases of age-and sex-matched normal right-Chinese young people, applications 3.0T GE MRI scanner to scan for high-resolution axial 3D FSPGR serial brain MRI data. Application of Partial Volume Classify BrainSuite software tools based on image signal strength will be divided into the brain gray matter and white matter and cerebrospinal fluid. On the surface by measuring the cortical gray matter of 65 538 points / white matter boundary and the gray matter / CSF boundary between the shortest of the three-dimensional Euclidean distance, access to each individual at every point in the original space mapping of cortical thickness and thickness distribution. The thickness of the original space and then maps affine MDT_69 space to remove the whole brain size differences of cortical thickness. Finally, the application of statistical methods to compare the surface of each cerebral hemisphere that gender differences in thickness and lateral resistance differences.
　　Results:
　　1. Gender differences: men left hemisphere cortical thickness was significantly larger than females (P <0.01) of the area mainly frontal gyrus rear, the rear middle frontal gyrus, inferior frontal gyrus, the lower part of the central gyrus, straight gyrus, orbital back back, after the central lower back, anterior cingulate gyrus, anterior superior temporal gyrus, anterior temporal gyrus, inferior temporal gyrus, parahippocampal gyrus, near the central lobule, precuneus, wedge leaves, occipital pole; left hemisphere female cortical thickness was significantly greater than males (P <0.01) of the region's main front for the superior frontal gyrus, anterior middle frontal gyrus, anterior inferior frontal gyrus, the upper back after the central, straight back to the front of the orbit back to the front, top on the back, the upper part of the top next time.
　　Right hemisphere cortical thickness was significantly greater than men women (P <0.01) of the area mainly frontal gyrus rear, the rear middle frontal gyrus, inferior frontal gyrus rear, lower part of the central gyrus, straight gyrus, orbital gyrus, After the return to the lower part of the central, superior temporal gyrus, the upper temporal gyrus, hippocampus, parahippocampal gyrus, the central lobule near the front, precuneus rear wedge leaf; right hemisphere cortical thickness was significantly larger than females males (P <0.01) of the region's main the superior frontal gyrus anterior, middle frontal gyrus anterior, inferior frontal gyrus front, straight back to the front, back to the front of the orbit, the upper part of the central gyrus, the upper back after the central, top back, bottom top next time.
　　2 side resistance differences: men left cortical thickness was significantly greater than the right (P <0.01) of the region anterior frontal gyrus, anterior inferior frontal gyrus, anterior leaflet near the central, upper middle temporal gyrus, temporal next time the middle; male right cortex was significantly greater than the thickness of the left (P <0.01) superior temporal gyrus of the upper region, parahippocampal gyrus lower part of the wedge leaves the front.
　　Women left cortical thickness was significantly greater than the right (P <0.01) of the superior temporal gyrus region the upper and lower back; women the right cortical thickness was significantly greater than the left (P <0.01) of the region under the superior temporal gyrus back, back before the middle of the central, middle temporal gyrus, inferior temporal gyrus rear, parahippocampal gyrus, back to back on top.
　　Conclusion: The thickness of the cerebral cortex were significantly related to gender differences in the regional wide frontal lobe, parietal lobe, temporal lobe and occipital lobe, and a significant difference involved the side resistance is less than the gender differences involved in the regional area.
　　Part III: The Chinese central sulcus of the gender differences in brain research
　　Objective: three-dimensional reconstruction of the central sulcus morphology and lateral resistance of gender differences.
　　Materials and Methods: 60 patients age-and sex-matched normal right-Chinese young people (male 30, female 30; average age of 23.3 ± 2.9), the application 3.0T GE MRI scanner to scan the sequence for high axial 3D FSPGR resolution brain MRI data. The establishment of the central sulcus using BrainVisa software three-dimensional model, and then measure the length of the central sulcus, width and depth. According to the central sulcus and lateral sulcus and the lateral position within the relationship will be divided into three types. Application of statistical methods to analyze the central sulcus of the morphological parameters and classification rules of gender differences and lateral resistance.
　　Results:
　　1 Morphological parameters of the central sulcus
　　1.1 Gender differences: Space Standardization ago, men left and right hemispheres of the central sulcus top long end of a long, Goushen and groove width were significantly larger than females (P <0.05). Standardized space, the men left and right sides of the central sulcus top long end of a long, wide trench Goushen and still are larger than females, but were not statistically significant (P> 0.05).
　　1.2 side of the resistance difference: male and female top left central sulcus long end of a long, Goushen and groove width were significantly greater than the right (P <0.05). Standardized space, the men left central sulcus of Goushen and groove width was significantly larger than the right (P <0.05); women left central sulcus was significantly greater than the right side of Goushen (P <0.05).
　　Central sulcus type 2
　　Men, mostly in central groove type b (connected with the inner side of the ditch, but not connected with the outside; left 63.33%, right 60%), while women are mostly in a type (not with the side or within the lateral sulcus connected; left 63.33%, 46.67% right). Central sulcus in the left side of the sub-type has a significant gender difference (P <0.05); its type in men and women there was no significant difference in side resistance (P> 0.05).
　　Conclusion: the central sulcus of the morphological parameters there are some differences between gender and side of the resistance, standardization can reduce the space the extent of their differences.
　　Conclusion and significance
　　The first time three-dimensional high-field MRI Morphometric data and computer methods of a more systematic study of the living human brain cortex of Chinese Sex and the side of the gender differences, the system to measure the volume of China's young cerebral cortex, cortical thickness, cortical surface area, degree of cortical folding and sulci of the normal morphological parameters, revealing the cerebral cortex of young Chinese men and women have differences in the heterogeneity of the law, the Chinese people to further explore the function of the brain and lateral resistance on the gender differences provide a basis for clinical neurological imaging diagnosis and treatment, and neuropsychological studies provide a reliable morphological basis.
　　Degree Year: 2010