— 1. Provide a concise overview of the normal asymmetry of human brain — 2. Review the leading mechanisms of the laterality brain process in order to facilitate the radiologic approach, with emphasis in an anatomic review —3. Illustrate and discuss the main MRI findings of these asymmetries

The human brain hemispheres display important anatomical differences, despite their exceptional correspondence. Distinct functions tend to be localized in the left or right hemisphere, demonstrating a marked lateralization. The early mechanism that underlies this process remains poorly understood. The handedness is considered the major example of hemispheric specialization, but recent advances in neuroimaging go beyond, providing a novel tool to document variation in symmetry and asymmetry, correlating age, gender, brain region and pathological state. After reviewing this exhibit, radiologists should be able to recognize the...

Introduction Brain laterality refers to the capability of human brain hemispheres to execute different functions, which is relatedtotheir anatomical asymmetries. The left hemisphere, for example, is normally dominant for language and logical processing, whereas the right hemisphere isdominant for spatial recognition. Some authors believe these anatomical differences, and therefore the lateralization, might be an evolutionary advantage. There are many theories, some of them based in anthropological studies, trying to explain the mechanisms involved in these cerebral specializations. Fig. 1Superior view of a 3D-reconstruction derived from...

We reviewed a variety of studies assessing asymmetries in brain structure and function. The gross anatomy and functional layout of the brain are organized asymmetrically, with hemispheric specializations for key aspects of language and motor function.The early mechanism that underlies this process remains poorly understood. The Yakovlevian anticlockwise torque and petalia showa geometric distortion of the brain hemispheres. The perisylvian region and language area display pronounced leftward asymmetry in most humans. Preferential use of right handis associatedwith greater cortical folding and gyrification within the motor-hand...

Department of Radiology Oswaldo Cruz German Hospital- Fleury Group Adress: João Julião, 331 Bela Vista - Sao Paulo, 01323-020, Brazil E-mail: [email protected]

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