María Guadalupe García-Gomar1,2
1Escuela Nacional de Estudios Superiores unidad Juriquilla, Universidad Nacional Autónoma de México, Querétaro, Mexico, 2Department of Radiology, Brainstem Imaging Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
Synopsis
Keywords: Neuro: Brain connectivity, Neuro: Brain, Neuro: Brain function
Understanding how different structures of our brain are interconnected allows us to better understand their function. Here we explore two main structures: the brainstem and cerebellum. The brainstem contains respiratory and cardiovascular control centers. Despite its fundamental role in survival, the brainstem has been studied less than other areas, in part due to several challenges in its imaging. Nonetheless, recent techniques are now allowing us a better understanding of its structure and connectivity. The cerebellum is known to have an important role in motor control and, more recently, its role in nonmotor cognitive and affective functions is being increasingly recognized.
Introduction
Knowing the basics of the anatomy and physiology of the CNS is critical for an appropriate understanding for those interested in working in neuroscience and related fields. Knowledge of the structure, connectivity, and function of different areas of the brain can play an important role in studying and understanding the brain, in both healthy and disease states. Here, two important structures will be explored in this regard: the brainstem and cerebellum.The brainstem
The brainstem lies in the lower part of our brain, and it is critical for survival since respiratory and cardiovascular control centers are found in this region1. In general, it is well accepted that the brainstem is the most evolutionarily conserved structure within the brain across species. Despite its fundamental role in different essential functions, the study of the brainstem has been neglected compared with research on other brain structures. This is likely due to several challenges, including its deep localization, the great number of compact nuclei that it contains within densely grouped white matter, its propensity for physiological noise, its very small size, and its complex anatomy2. Nonetheless, recent techniques and methodological advances (e.g. ultrahigh field MRI) are allowing us to have a better understanding of the brainstem structure and its anatomical and functional connectivity3–5. The cerebellum
The cerebellum (from the Latin for “little brain”) has been known to have an important role in motor control, motor learning and balance. It is being increasingly recognized as well for its role in nonmotor cognitive, emotional and affective functions6,7. This structure is connected by direct or indirect synapsis with different areas of the brainstem, spinal cord and different cortical and subcortical regions8. The cerebellum receives information from the cerebral cortex, muscles, tendons, joints and from vestibular nuclei. This area receives input from regions that plan and initiate complex movements and also receive afferent information from sensory systems (i.e. muscles and joints) that monitor the course of movements. The cerebellum enables a comparison of an intended movement with the actual movement9. Therefore, this region is responsible of corrections of motor errors and it is involved in motor learning10. Acknowledgements
National Institute on Aging, NIH: R01-AG063982References
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