Department of Psychology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USAUnited States
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With the ravaging effects of glucose related diseases (such as diabetes) on the rise, an increased understanding of the central mechanisms involved in glucose mobilization and absorption, and the potential development of the metabolic syndrome, is becoming increasingly important. Although, substantive efforts have been expended to better understand the peripheral mechanisms involved with the systemic processing of glucose, there remains a paucity of research dedicated to the central neural aspects largely involved in the mobilization and absorption of blood glucose. Despite this lack of research, the relationship between emotional states of anger or fear and those oppositional processes associated with quiescent states or digestive uptake have been clearly related to blood glucose levels.1-3 Moreover, and perhaps most relevant here, is that the differential emotional states just described have been established with origins in cerebral laterality and with regulatory control mechanisms largely relegated to the frontal lobes and executive brain systems.
DIABETES RESEARCH Mini Review Brain Mechanisms in Blood Glucose * *Corresponding author Mobilization and Absorption: The Role of David W. Harrison, PhD Director the Left and the Right Frontal Regions in Behavioral Neuroscience Laboratory Psychology Department College of Science the Regulatory Control of Blood Glucose Virginia Polytechnic Institute Blacksburg, VA 24061-0436, USA Levels Tel. (540) 231-4422 E-mail: dwh@vt.edu * Benjamin B. DeVore, MS; David W. Harrison, PhD* Volume 3 : Issue 2 Article Ref. #: 1000DROJ3131 Department of Psychology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA Article History th Received: February 15th, 2017 th With the ravaging effects of glucose related diseases (such as diabetes) on the rise, Accepted: April 17 , 2017 th an increased understanding of the central mechanisms involved in glucose mobilization and Published: April 19 , 2017 absorption, and the potential development of the metabolic syndrome, is becoming increas- ingly important. Although, substantive efforts have been expended to better understand the Citation peripheral mechanisms involved with the systemic processing of glucose, there remains a pau- DeVore BB, Harrison DW. Brain mech- city of research dedicated to the central neural aspects largely involved in the mobilization and anisms in blood glucose mobilization and absorption: The role of the left and absorption of blood glucose. Despite this lack of research, the relationship between emotional the right frontal regions in the regula- states of anger or fear and those oppositional processes associated with quiescent states or di- tory control of blood glucose levels.
1-3 gestive uptake have been clearly related to blood glucose levels. Moreover, and perhaps most Diabetes Res Open J. 2017; 3(2): 17- relevant here, is that the differential emotional states just described have been established with 19. doi: 10.17140/DROJ-3-131 origins in cerebral laterality and with regulatory control mechanisms largely relegated to the 4-6 frontal lobes and executive brain systems.4-6 We have provided evidence with the potential to bridge this gap between brain the- ory and research on peripheral mechanisms with specializations of the right brain for intense 7-10 emotional states and sympathetic drive7-10 and with somewhat oppositional specializations of the left brain for quiescent states and perhaps parasympathetic drive. Functional cerebral sys- 11-14 tems theory demonstrates the regulatory control over sympathetic drive by the frontal lobe executive regions, where incremental blood pressure, heart rate, sweating, cholesterol levels, and blood glucose levels may provide the biological resources and reserves for the fight with relevance to insure success in meeting the potentially coercive threat or challenge. Further- more, cerebral balance theory7 supports oppositional mechanisms with quiescent states and the establishment of resource reserves largely by left cerebral systems. This brief review of current neuropsychological research will present a theoretical foundation, based upon Alexander Lu- ria’s functional cerebral systems theory, for the preferential activation of glucose metabolism by the right cerebral hemisphere (Figure 1).
Fundamental to the presented argument is the theoretical construct, that the majority of emotional processing, particularly intense emotions such as anger or fear, are lateralized to the right hemisphere.15 Research in our lab looking at violent-prone individuals has consistently supported this theory by showing decreased frontal lobe regulation of right posterior anger and 4,16 negative emotionally responsive brain regions.4,16 Of further import to the theory of right hemi- Copyright spheric glucose mobilization is evidence showing sympathetic response is substantially under ©2017 Harrison DW. This is an open access article distributed un- right hemispheric control and that overall cardiovascular recruitment is driven by right hemi- der the Creative Commons Attribu- spheric activation. Current research efforts,17 comparison studies of the left-versus-right sided tion 4.0 International License (CC 18 cerebrovascular accidents, and unilateral intracarotid sodium amobarbital injections (UISAI) BY 4.0), which permits unrestricted 18 [Wada technique] all support the relative role of the right hemisphere in sympathetic response. use, distribution, and reproduction in any medium, provided the origi- nal work is properly cited. Given the integral role of blood glucose as the major fuel source for the brain, it follows
that processes such as intense emotion or increased sympathetic idence for the role of the right hemisphere in glucose mobiliza- drive would require increase levels of glucose for mobilization tion and the potentially opposition role of the left hemisphere in of action.2 To help illustrate how glucose may be regulated (or glucose absorption, digestive advance, and quiescent emotional deregulated in certain cases), our lab has proposed the quadrant states cannot be ignored. With the increasing costs and health theory of neural functioning. Anatomically, the anterior and pos- risks associated with glucose related diseases, efforts must con- terior “quadrants” of the brain communicate within each hemi- tinue to be made to both determine the specific role of the right sphere via the longitudinal tract. Similarly, the anterior and pos- hemisphere in both glucose mobilization and gluconeogenesis.
terior regions of each hemisphere communicate with the parallel With greater understanding of these processes within lateralized region across the corpus callosum.19 Given this general wiring of brain regions, cause specific treatment methodologies can be the various regions, each quadrant appears to compete for cere- identified and utilized.
bral resources, specifically glucose, for a given function. Due to the overall regulatory role of the frontal lobe, if the right frontal CONFLICTS OF INTEREST region were to exhaust the general supply of glucose available, posteriorly there would be an “unbridling” or cortical release of The authors declare that they have no conflicts of interest.
processes typically under frontal control. Right posterior release or activation has been shown to result in increased sympathetic