The Neural Tract Between the Hypothalamus and Basal Forebrain in the Ascending Reticular Activating System: A Diffusion Tensor Tractography Study

Page: [369 - 372] Pages: 4

  • * (Excluding Mailing and Handling)

Abstract

Objective: Ascending Reticular Activating System (ARAS) has a key role in consciousness. The ARAS is a complex network consisting of a portion of the brainstem reticular formation, nonspecific thalamic nuclei, hypothalamus, Basal Forebrain (BF), and cerebral cortex. We examined the reconstruction method and features of the neural tract between the hypothalamus and the BF in normal subjects, using Diffusion Tensor Tractography (DTT).

Methods: Twenty-three healthy subjects were recruited. The ARAS between the hypothalamus and the BF was reconstructed by two Regions of Interest (ROIs): 1) seed ROI - the isolated green portion for the BF on the color map, 2) target ROI - the hypothalamus on the axial image. DTT parameters of the ARAS between the hypothalamus and the BF were examined.

Results: Among 46 hemispheres in 23 normal subjects, 24 hemispheres (52.2 %) were identified in the ARAS between the hypothalamus and the BF. The reconstructed ARAS between the hypothalamus and the BF connected from the hypothalamus to the commissural level and anteriorly through the anterior commissure and then reached the BF.

Conclusion: Using DTT, the ARAS between the hypothalamus and the BF was identified in normal subjects. Because the hypothalamus and BF are related to the regulation of wakefulness and sleep, our reconstruction method and results would be useful in the research on sleep and wakefulness aspects of consciousness.

Keywords: Ascending reticular activating system, basal forebrain, hypothalamus, consciousness, DTT, basal forebrain.

Graphical Abstract

[1]
Paus T. Functional anatomy of arousal and attention systems in the human brain. Prog Brain Res 2000; 126: 65-77.
[2]
Zeman A. Consciousness. Brain 2001; 124(Pt 7): 1263-89.
[3]
Daube JR. Medical neurosciences: An approach to anatomy, pathology, and physiology by systems and levels. 2nd ed. Boston: Little, Brown and Co. 1986.
[4]
Weiss N, Galanaud D, Carpentier A, Naccache L, Puybasset L. Clinical review: Prognostic value of magnetic resonance imaging in acute brain injury and coma. Crit Care 2007; 11(5): 230.
[5]
Jang SH, Kwon HG. The direct pathway from the brainstem reticular formation to the cerebral cortex in the ascending reticular activating system: A diffusion tensor imaging study. Neurosci Lett 2015; 606: 200-3.
[6]
Basser PJ, Pierpaoli C. Microstructural and physiological features of tissues elucidated by quantitative-diffusion-tensor MRI. J Magn Reson B 1996; 111(3): 209-19.
[7]
Mori S, Crain BJ, Chacko VP, van Zijl PC. Three-dimensional tracking of axonal projections in the brain by magnetic resonance imaging. Ann Neurol 1999; 45(2): 265-9.
[8]
Yang HS, Kwon HG, Hong JH, Hong CP, Jang SH. The rubrospinal tract in the human brain: Diffusion tensor imaging study. Neurosci Lett 2011; 504(1): 45-8.
[9]
Jang SH, Kwon HG. Connectivity of inferior cerebellar peduncle in the human brain: A diffusion tensor imaging study. Neural Netw World 2016; 5: 439-47.
[10]
Edlow BL, Takahashi E, Wu O, et al. Neuroanatomic connectivity of the human ascending arousal system critical to consciousness and its disorders. J Neuropathol Exp Neurol 2012; 71(6): 531-46.
[11]
Yeo SS, Chang PH, Jang SH. The ascending reticular activating system from pontine reticular formation to the thalamus in the human brain. Front Hum Neurosci 2013; 7: 416.
[12]
Jang SH, Lim HW, Yeo SS. The neural connectivity of the intralaminar thalamic nuclei in the human brain: A diffusion tensor tractography study. Neurosci Lett 2014; 579: 140-4.
[13]
Jang SH, Kwon HG. The ascending reticular activating system from pontine reticular formation to the hypothalamus in the human brain: A diffusion tensor imaging study. Neurosci Lett 2015; 590: 58-61.
[14]
Jang SH, Kwon HG. The direct pathway from the brainstem reticular formation to the cerebral cortex in the ascending reticular activating system: A diffusion tensor imaging study. Neurosci Lett 2015; 606: 200-3.
[15]
Jang SH, Kim SH, Lim HW, Yeo SS. Injury of the lower ascending reticular activating system in patients with hypoxic-ischemic brain injury: Diffusion tensor imaging study. Neuroradiology 2014; 56(11): 965-70.
[16]
Smith SM, Jenkinson M, Woolrich MW, et al. Advances in functional and structural MR image analysis and implementation as FSL. Neuroimage 2004; 23: S208-19.
[17]
Duvernoy HM, Bourgouin P. The human brain: Surface, three-dimensional sectional anatomy with MRI, and blood supply. 2nd ed. Wien, New York: Springer 1999.
[18]
Oishi K, Faria AV, van Zijl PCM, Mori S. MRI Atlas of Human white matter. Elsevier Science 2010.
[19]
Wedeen VJ, Wang RP, Schmahmann JD, et al. Diffusion spectrum magnetic resonance imaging (DSI) tractography of crossing fibers. Neuroimage 2008; 41(4): 1267-77.
[20]
Parker GJ, Alexander DC. Probabilistic anatomical connectivity derived from the microscopic persistent angular structure of cerebral tissue. Philos Trans R Soc Lond B Biol Sci 2005; 360(1457): 893-902.
[21]
Edlow BL, Haynes RL, Takahashi E, et al. Disconnection of the ascending arousal system in traumatic coma. J Neuropathol Exp Neurol 2013; 72(6): 505-23.
[22]
Yamada K, Sakai K, Akazawa K, Yuen S, Nishimura T. MR tractography: A review of its clinical applications. Magn Reson Med Sci 2009; 8(4): 165-74.
[23]
You ZB, Chen YQ, Wise RA. Dopamine and glutamate release in the nucleus accumbens and ventral tegmental area of rat following lateral hypothalamic self-stimulation. Neuroscience 2001; 107(4): 629-39.
[24]
Szymusiak R, McGinty D. Hypothalamic regulation of sleep and arousal. Ann N Y Acad Sci 2008; 1129: 275-86.
[25]
Newcombe VF, Williams GB, Scoffings D, et al. Aetiological differences in neuroanatomy of the vegetative state: Insights from diffusion tensor imaging and functional implications. J Neurol Neurosurg Psychiatry 2010; 81(5): 552-61.
[26]
Lin JS, Anaclet C, Sergeeva OA, Haas HL. The waking brain: An update. Cell Mol Life Sci 2011; 68(15): 2499-512.