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Action Potential of Lateral Geniculate Neurons at Low Threshold Currents: Simulation Study
Abstract:Lateral Geniculate Nucleus (LGN) is the relay center in the visual pathway as it receives most of the input information from retinal ganglion cells (RGC) and sends to visual cortex. Low threshold calcium currents (IT) at the membrane are the unique indicator to characterize this firing functionality of the LGN neurons gained by the RGC input. According to the LGN functional requirements such as functional mapping of RGC to LGN, the morphologies of the LGN neurons were developed. During the neurological disorders like glaucoma, the mapping between RGC and LGN is disconnected and hence stimulating LGN electrically using deep brain electrodes can restore the functionalities of LGN. A computational model was developed for simulating the LGN neurons with three predominant morphologies each representing different functional mapping of RGC to LGN. The firings of action potentials at LGN neuron due to IT were characterized by varying the stimulation parameters, morphological parameters and orientation. A wide range of stimulation parameters (stimulus amplitude, duration and frequency) represents the various strengths of the electrical stimulation with different morphological parameters (soma size, dendrites size and structure). The orientation (0-1800) of LGN neuron with respect to the stimulating electrode represents the angle at which the extracellular deep brain stimulation towards LGN neuron is performed. A reduced dendrite structure was used in the model using Bush–Sejnowski algorithm to decrease the computational time while conserving its input resistance and total surface area. The major finding is that an input potential of 0.4 V is required to produce the action potential in the LGN neuron which is placed at 100 μm distance from the electrode. From this study, it can be concluded that the neuroprostheses under design would need to consider the capability of inducing at least 0.4V to produce action potentials in LGN.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1110193Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1645
 K. A. Schneider, M. C. Richter, and S. Kastner, “Retinotopic organization and functional subdivisions of the human lateral geniculate nucleus: a high-resolution functional magnetic resonance imaging study.,” J. Neurosci., vol. 24, no. 41, pp. 8975–85, Oct. 2004.
 T. L. Hickey and R. W. Guillery, “A study of Golgi preparations from the human lateral geniculate nucleus.,” J. Comp. Neurol., vol. 200, no. 4, pp. 545–77, Aug. 1981.
 R. Zomorrodi, A. S. Ferecskó, K. Kovács, H. Kröger, and I. Timofeev, “Analysis of morphological features of thalamocortical neurons from the ventroposterolateral nucleus of the cat,” J. Comp. Neurol., vol. 518, no. 17, pp. 3541–3556, 2010.
 R. W. Guillery, “A study of Golgi preparations from the dorsal lateral geniculate nucleus of the adult cat.,” J. Comp. Neurol., vol. 128, no. 1, pp. 21–50, 1966.
 S. LeVay and D. Ferster, “Relay cell classes in the lateral geniculate nucleus of the cat and the effects of visual deprivation.,” J. Comp. Neurol., vol. 172, no. 4, pp. 563–84, Apr. 1977.
 L. Stanford, M. Friedlander, and S. Sherman, “Morphology of physiologically identified W-cells in the C laminae of the cat’s lateral geniculate nucleus,” J. Neurosci., vol. 1, no. 6, pp. 578–584, Jun. 1981.
 B. Dreher, Y. Fukada, and R. W. Rodieck, “Identification, classification and anatomical segregation of cells with X-like and Y-like properties in the lateral geniculate nucleus of old-world primates.,” J. Physiol., vol. 258, no. 2, pp. 433–452, Jun. 1976.
 V. Crunelli, S. Lightowler, and C. E. Pollard, “A T-type Ca2+ current underlies low-threshold Ca2+ potentials in cells of the cat and rat lateral geniculate nucleus.,” J. Physiol., vol. 413, no. 1, pp. 543–561, Jun. 1989.
 H. Jahnsen and R. Llinás, “Electrophysiological properties of guinea-pig thalamic neurones: an in vitro study.,” J. Physiol., vol. 349, pp. 205–26, Apr. 1984.
 H. Jahnsen and R. Llinás, “Ionic basis for the electro-responsiveness and oscillatory properties of guinea-pig thalamic neurones in vitro.,” J. Physiol., vol. 349, no. 1, pp. 227–247, Apr. 1984.
 Y. Amarillo, G. Mato, and M. S. Nadal, “Analysis of the role of the low threshold currents IT and Ih in intrinsic delta oscillations of thalamocortical neurons,” Front. Comput. Neurosci., vol. 9, no. May, pp. 1–9, 2015.
 C. C. McIntyre, W. M. Grill, D. L. Sherman, and N. V Thakor, “Cellular effects of deep brain stimulation: model-based analysis of activation and inhibition.” J. Neurophysiol., vol. 91, no. 4, pp. 1457–1469, 2004.
 Destexhe, M. Neubig, D. Ulrich, and J. Huguenard, “Dendritic lowthreshold calcium currents in thalamic relay cells.,” J. Neurosci., vol. 18, no. 10, pp. 3574–3588, 1998.