A parallel neural circuit model for bimodal distribution of reaction time in a predictive saccade task
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摘要: 在执行精确时间内产生预期眼动的任务时,猕猴的反应时间呈现双峰分布.对这一现象,本文设计了包含大脑皮层的顶内沟外侧区(lateral intraparietal area ,LIP)和辅助眼区(supplementary eye fields,SEF)、基底节(basal ganglia,BG)与上丘脑(superior colliculus,SC)在内的并行神经环路模型,通过计算模拟复现出双峰分布.本文探究了该分布的神经机制,发现SEF和LIP神经元群体之间的竞争过程导致了2个峰的出现,并且SEF脑区主要负责预期性眼动,主导了第1个峰的出现,LIP脑区主要负责由视觉刺激引发的反应性眼动,主导了第2个峰的出现.本文进一步地讨论了影响双峰分布形态的关键参数,从计算神经科学的角度探索了时间预期执行的过程.Abstract: In predictive saccade tasks within precise time intervals, the reaction time of macaque exhibits a bimodal distribution. To investigate this phenomenon further, a parallel neural circuit model that includes the lateral intraparietal area (LIP), supplementary eye fields (SEF) in the cerebral cortex, the basal ganglia (BG) and superior colliculus (SC) is proposed in this study. Model simulations successfully reproduced a bimodal distribution. Competitive interaction among neuronal populations in SEF and LIP regions was found to give rise to two peaks. SEF region primarily was found to handle predictive saccades and dominated the first peak, while LIP region was found to be responsible for visually evoked reactive saccades and dominated the second peak. Key parameters that influence morphology of bimodal distribution are discussed. The process of time expectation from the perspective of computational neuroscience is explored.
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Key words:
- predictive saccade /
- reaction time /
- bimodal distribution /
- parallel neural circuit /
- neurodynamics
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图 1 并行神经回路模型(a)与模拟实验流程(b)
a. 彩色实心圆代表神经元群体;橙色表示兴奋性神经元(E),蓝色为抑制性神经元(Ⅰ);带有箭头的线段表示神经元的突触投射与投射的起始、终点所在;线段的颜色与箭头形状表明突触的性质,红色、三角形为兴奋性,蓝色、圆形为抑制性;神经元群体之间或之内的连接方式皆为全连接.b. 0~1 000 ms,神经元群体始终接收背景噪声;250~260 ms,SEF的E神经元接收编码了cue的神经输入input Ⅰ;而在0~600 ms中,LIP的Ⅰ神经元始终接收编码注视点信息的神经输入input Ⅱ;在600 ms处撤销input Ⅱ以模拟撤去注视点,系统继续演化至1 000 ms.
图 3 模型引起眼动时各区域内神经元群体活动情况
a1~a3. 由SEF兴奋性神经元(SEFE)首先到达放电阈值,引起眼动;b1~b3. 由LIP的兴奋性神经元(LIPE)抑制SEFE后到达放电阈值引起眼动;c1~c3,由LIPE首先达到放电阈值引发眼动.所有子图的横坐标为模拟时间,单位为ms,坐标零点对齐至撤去注视点的600 ms处;纵坐标为放电频率,单位为Hz.图3编号为1的第1行子图中,黑、绿、红线依次表示SEFE神经元、SEF内第2群抑制性神经元(SEFⅡ)和LIPE神经元的放电活动;第2行子图中,黑、红、绿线依次表示BG内CDⅠ神经元,CDⅡ神经元和SNr神经元的放电活动;第3行子图中,黑、红线依次表示SC的兴奋性神经元(SCE)和抑制性神经元(SCI).图3中各参数与图2-a1中一致.
表 1 图2-a1与图2-a2中电导G区别
突触连接最大
电导名称图2-a1中
G/nS图2-a2中
G/nS$ {G}_{{\rm{Sef{\text{Ⅱ}}2Sef}}{\text{Ⅱ}}}^{{\rm{GABAb}}} $ 0.110 0.250 $ {G}_{{\rm{LipE2Sef}}\text{Ⅱ}}^{{\rm{AMPA}}} $ 0.135 0.300 $ {G}_{{\rm{LipE2LipE}}}^{{\rm{AMPA}}} $ 0.050 0.030 $ {G}_{{\rm{LipE2LipE}}}^{{\rm{NMDA}}} $ 0.170 0.200 $ {G}_{{\rm{ext,AMPA}}}^{{\rm{MT2LipI}}} $ 4.200 6.200 $ {G}_{{\rm{LipE2CD}}\text{Ⅱ}}^{{\rm{AMPA}}} $ 0.075 0.140 $ {G}_{{\rm{LipE2ScE}}}^{{\rm{AMPA}}} $ 0.500 1.000 -
[1] BADLER J B,HEINEN S J. Anticipatory movement timing using prediction and external cues[J]. The Journal of Neuroscience,2006,26(17):4519 doi: 10.1523/JNEUROSCI.3739-05.2006 [2] BUBIC A,VON CRAMON D Y,SCHUBOTZ R I. Prediction,cognition and the brain[J]. Frontiers in Human Neuroscience,2010,4:25 [3] MISSAL M,HEINEN S J. Facilitation of smooth pursuit initiation by electrical stimulation in the supplementary eye fields[J]. Journal of Neurophysiology,2001,86(5):2413 doi: 10.1152/jn.2001.86.5.2413 [4] MISSAL M,HEINEN S J. Supplementary eye fields stimulation facilitates anticipatory pursuit[J]. Journal of Neurophysiology,2004,92(2):1257 doi: 10.1152/jn.01255.2003 [5] OHMAE S,LU X F,TAKAHASHI T,et al. Neuronal activity related to anticipated and elapsed time in macaque supplementary eye field[J]. Experimental Brain Research,2008,184(4):593 doi: 10.1007/s00221-007-1234-3 [6] DE HEMPTINNE C,NOZARADAN S,DUVIVIER Q,et al. How do primates anticipate uncertain future events?[J]. The Journal of Neuroscience,2007,27(16):4334 doi: 10.1523/JNEUROSCI.0388-07.2007 [7] DE HEMPTINNE C,LEFÈVRE P,MISSAL M. Influence of cognitive expectation on the initiation of anticipatory and visual pursuit eye movements in the rhesus monkey[J]. Journal of Neurophysiology,2006,95(6):3770 doi: 10.1152/jn.00007.2006 [8] AMEQRANE I,POUGET P,WATTIEZ N,et al. Implicit and explicit timing in oculomotor control[J]. PLoS One,2014,9(4):e93958 doi: 10.1371/journal.pone.0093958 [9] 韩志会. 时间精确的预测性眼动的灵长类模型建立及影响因素的研究[D]. 北京:北京师范大学,2016 [10] REDDI B A J,ASRRESS K N,CARPENTER R H S. Accuracy,information,and response time in a saccadic decision task[J]. Journal of Neurophysiology,2003,90(5):3538 doi: 10.1152/jn.00689.2002 [11] WONG K F,WANG X J. A recurrent network mechanism of time integration in perceptual decisions[J]. The Journal of Neuroscience,2006,26(4):1314 doi: 10.1523/JNEUROSCI.3733-05.2006 [12] SHICHINOHE N,AKAO T,KURKIN S,et al. Supplementary eye fields (SEF) and memory-based smooth pursuit eye movements:working memory and decision processes[J]. Neuroscience Research,2009,65:S170 [13] MARTINEZ-TRUJILLO J C,WANG H Y,CRAWFORD J D. Electrical stimulation of the supplementary eye fields in the head-free macaque evokes kinematically normal gaze shifts[J]. Journal of Neurophysiology,2003,89(6):2961 doi: 10.1152/jn.01065.2002 [14] TOBLER P N,MÜRI R M. Role of human frontal and supplementary eye fields in double step saccades[J]. Neuroreport,2002,13(2):253 doi: 10.1097/00001756-200202110-00016 [15] RUSSO G S,BRUCE C J. Supplementary eye field:representation of saccades and relationship between neural response fields and elicited eye movements[J]. Journal of Neurophysiology,2000,84(5):2605 doi: 10.1152/jn.2000.84.5.2605 [16] PARENT A,HAZRATI L N. Functional anatomy of the basal ganglia: I. The cortico-basal ganglia-thalamo-cortical loop[J]. Brain Research Reviews,1995,20(1):91 doi: 10.1016/0165-0173(94)00007-C [17] GOFFART L,CECALA A,GANDHI N. Does the saccade-related burst in the superior colliculus convey commands related to the future location of a moving target?[J]. Journal of Vision,2016,16(12):98 doi: 10.1167/16.12.98 [18] HANES D P,WURTZ R H. Interaction of the frontal eye field and superior colliculus for saccade generation[J]. Journal of Neurophysiology,2001,85(2):804 doi: 10.1152/jn.2001.85.2.804 [19] 陈宜张. 突触[M]. 上海:上海科学技术出版社,2014 [20] ADESNIK H,BRUNS W,TANIGUCHI H,et al. A neural circuit for spatial summation in visual cortex[J]. Nature,2012,490(7419):226 doi: 10.1038/nature11526 [21] BOUSSAOUD D,BARTH T M,WISE S P. Effects of gaze on apparent visual responses of frontal cortex neurons[J]. Experimental Brain Research,1993,93(3):423 [22] BISCALDI M,WEBER H,FISCHER B,et al. Mechanisms for fixation in man:evidence from saccadic reaction times[J]. Studies in Visual Information Processing,1995,6:145 [23] FRISCHEN A,SMILEK D,EASTWOOD J D,et al. Inhibition of return in response to gaze cues:the roles of time course and fixation cue[J]. Visual Cognition,2007,15(8):881 doi: 10.1080/13506280601112493 [24] WANG X J. Synaptic basis of cortical persistent activity:the importance of NMDA receptors to working memory[J]. The Journal of Neuroscience,1999,19(21):9587 doi: 10.1523/JNEUROSCI.19-21-09587.1999 -