Components of the neural signal underlying congenital nystagmus

被引：0
作者：
Ozgur E. Akman
David S. Broomhead
Richard V. Abadi
Richard A. Clement
机构：
[1] University of Exeter,Centre for Systems, Dynamics and Control, College of Engineering, Mathematics and Physical Sciences
[2] University of Manchester,School of Mathematics
[3] University of Manchester,Faculty of Life Sciences
[4] National University of Ireland,Department of Psychology
[5] University College London,Institute of Child Health
[6] University of Exeter,Centre for Systems, Dynamics and Control, College of Engineering, Mathematics and Physical Sciences
来源：
Experimental Brain Research | 2012年 / 220卷
关键词：
Nystagmus; Muscle plant; Time constant; Time series analysis; Nonlinear dynamics;
D O I：
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中图分类号：
学科分类号：
摘要：
Congenital nystagmus is an involuntary bilateral horizontal oscillation of the eyes that develops soon after birth. In this study, the time constants of each of the components of the neural signal underlying congenital nystagmus were obtained by time series analysis and interpreted by comparison with those of the normal oculomotor system. In the neighbourhood of the fixation position, the system generating the neural signal is approximately linear with 3 degrees of freedom. The shortest time constant was in the range of 7–9 ms and corresponds to a normal saccadic burst signal. The other stable time constant was in the range of 22–70 ms and corresponds to the slide signal. The final time constant characterises the unidentified neural mechanism underlying the unstable drift component of the oscillation cycle and ranges between 31 and 32 ms across waveforms. The characterisation of this unstable time constant poses a challenge for the modelling of both the normal and abnormal oculomotor control system. We tentatively identify the unstable component with the eye position signal supplied to the superior colliculus in the normal eye movement system and explore some of the implications of this hypothesis.
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页码：213 / 221
页数：8
相关论文
共 85 条
[1]  
Abadi RV(2002)Motor and sensory characteristics of infantile nystagmus Br J Ophthalmol 86 1152-1160
[2]  
Bjerre A(1986)Waveform characteristics in congenital nystagmus Doc Ophthalmol 64 153-167
[3]  
Abadi RV(1997)Dynamical systems analysis: a new method of analysing congenital nystagmus waveforms Exp Brain Res 117 355-361
[4]  
Dickinson CM(2005)Eye movement instabilities and congenital nystagmus can be predicted by a nonlinear dynamics model of the saccadic system J Math Biol 51 661-694
[5]  
Abadi RV(2006)Nonlinear time series analysis of jerk congenital nystagmus J Comput Neurosci 21 153-170
[6]  
Broomhead DS(2009)Bifurcation theory explains waveform variability in a congenital eye movement disorder J Comput Neurosci 26 321-329
[7]  
Clement RA(1972)Accuracy of saccadic eye movements and maintenance of eccentric eye positions in the dark Vision Res 13 1021-1034
[8]  
Whittle JP(1989)Time series analysis Proc R Soc Lond A 423 103-121
[9]  
Worfolk R(1975)Congenital nystagmus waveforms and foveation strategy Doc Ophthalmol 39 155-182
[10]  
Akman OE(2011)Motor functions of the superior colliculus Annu Rev Neurosci 34 205-231
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