• 【一种颜色或然棱镜位移后效应。】 复制标题 收藏 收藏
    DOI:10.1068/p140691 复制DOI
    作者列表:Donderi DC,Jolicoeur P,Berg I,Grimes R
    BACKGROUND & AIMS: :Observers were trained to point with feedback to red and blue dots whose images had been laterally displaced in opposite directions by a reversible prism. On pretraining and posttraining trials the red and blue dots were aligned vertically in the absence of visual orientation cues. The alignment was modified by the pointing training on the posttraining trials. The colors were aligned in the direction of their prior prismatic displacement. One control experiment showed that the alignment aftereffect requires feedback during the pointing task. Another experiment in which observers pointed to the red and blue dots with opposite arms showed that pointing to both dots with the same arm was necessary to produce the alignment aftereffect. Changes in the perceived position of objects in the visual field occur when changes in perceived limb position cannot compensate for a sensorimotor conflict. Eye torsion or fixation displacements are proposed as alternative mechanisms mediating the aftereffect.
    背景与目标: : 观察者经过训练,可以通过反馈指向红色和蓝色的点,这些点的图像已被可逆棱镜沿相反方向横向移位。在训练前和训练后试验中,在没有视觉方向提示的情况下,红色和蓝色点垂直对齐。通过训练后试验的定点训练修改了对齐方式。颜色在其先前的棱柱形位移方向上对齐。一个控制实验表明,对准后效应需要在指向任务期间进行反馈。观察者指向具有相反臂的红色和蓝色点的另一个实验表明,指向具有相同臂的两个点对于产生对齐后效是必要的。当感知到的肢体位置的变化不能补偿感觉运动冲突时,就会发生物体在视野中感知位置的变化。提出了眼扭转或固定位移作为介导后效的替代机制。
  • 【消除运动后效: 模式特异性的证据。】 复制标题 收藏 收藏
    DOI:10.1068/p030267 复制DOI
    作者列表:Mayhew JE
    BACKGROUND & AIMS: -2
    背景与目标: -2
  • 【人体运动后效反应的功能相关和描述的连通性模式证实了视觉-前庭的相互作用。】 复制标题 收藏 收藏
    DOI:10.1016/j.neuroimage.2018.02.057 复制DOI
    作者列表:Rühl RM,Bauermann T,Dieterich M,Zu Eulenburg P
    BACKGROUND & AIMS: :The visual motion aftereffect (MAE) is the most prominent aftereffect in the visual system. Regarding its function, psychophysical studies suggest its function to be a form of sensory error correction, possibly also triggered by incongruent visual-vestibular stimulation. Several observational imaging experiments have deducted an essential role for region MT+ in the perception of a visual MAE but not provided conclusive evidence. Potential confounders with the MAE such as ocular motor performance, attention, and vection sensations have also never been controlled for. Aim of this neuroimaging study was to delineate the neural correlates of MAE and its subjacent functional connectivity pattern. A rotational MAE (n = 22) was induced using differing visual stimuli whilst modulating ocular motor parameters in a 3T scanner. Data was analyzed with SPM12. Eye movements as a response to the same stimuli were studied by means of high-resolution videooculography. Analysis for all stimuli gave bilateral activations along the dorsal visual stream with an emphasis on area MT. The onset of a visual MAE revealed an additional response in the right medial superior temporal area (MST) and a concurrent deactivation of vestibular hub region OP2. There was no correlation for the BOLD effects during the MAE with either ocular motor or attention parameters. The functional correlate of a visual MAE in humans may be represented in the interaction between region MT and area MST. This MAE representation is independent of a potential afternystagmus, attention and the presence of egomotion sensations. Connectivity analyses showed that in the event of conflicting visual-vestibular motion information (here MAE) area MST and area OP2 may act as the relevant mediating network hubs.
    背景与目标: : 视觉运动后效 (MAE) 是视觉系统中最突出的后效。关于其功能,心理物理研究表明其功能是感觉错误校正的一种形式,也可能是由不一致的视觉前庭刺激触发的。几项观测成像实验已扣除了MT区域在视觉MAE感知中的重要作用,但未提供确凿的证据。与MAE的潜在混杂因素,例如眼部运动性能,注意力和视觉感觉,也从未得到控制。这项神经影像学研究的目的是描述MAE及其以下功能连接模式的神经相关性。在3t扫描仪中调节眼球运动参数的同时,使用不同的视觉刺激诱导旋转MAE (n   =   22)。数据用spm12进行分析。通过高分辨率视频眼电图研究了眼动作为对相同刺激的反应。对所有刺激的分析都沿背侧视觉流进行了双边激活,重点是MT区域。视觉MAE的发作揭示了右内侧上颞区 (MST) 的额外反应以及前庭中枢区op2的同时失活。MAE期间的BOLD效应与眼部运动或注意力参数均无相关性。人类视觉MAE的功能相关性可以在区域MT和区域MST之间的相互作用中表示。这种MAE表示与潜在的眼震,注意力和运动感觉的存在无关。连通性分析表明,如果视觉-前庭运动信息 (此处为MAE) 发生冲突,则MST和OP2区域可能充当相关的中介网络集线器。
  • 【刺激部位对触觉运动后效流行的影响。】 复制标题 收藏 收藏
    DOI:10.1007/s00221-009-2144-3 复制DOI
    作者列表:Planetta PJ,Servos P
    BACKGROUND & AIMS: :The motion aftereffect (MAE) refers to the apparent motion of a stationary stimulus following adaptation to a continuously moving stimulus. There is a growing consensus that the fast adapting (FA) rather than the slowly adapting (SA) afferent units mediate the tactile version of the MAE. The present study investigated which FA units underlie the tactile MAE by measuring its prevalence, duration, and vividness on different skin areas that vary in their composition of FA units. Specifically, the right cheek, volar surface of the forearm, and volar surface of the hand were adapted using a ridged cylindrical drum, which rotated at 60 rpm for 120 s. Although there was no difference in duration or vividness between the skin surfaces tested, the tactile MAE was reported twice as often on the hand compared to the cheek and forearm, which did not differ significantly from one another. This suggests that the FA I units in the glabrous skin and the hair follicle and/or the FA I and field units in the hairy skin contribute to the tactile MAE.
    背景与目标: : 运动后效 (MAE) 是指适应连续运动的刺激后的固定刺激的表观运动。越来越多的共识是,快速适应 (FA) 而不是缓慢适应 (SA) 传入单元介导了MAE的触觉版本。本研究通过测量触觉MAE的患病率,持续时间和在不同皮肤区域的生动性 (FA单位的组成不同),调查了哪些FA单位是触觉MAE的基础。具体地说,右脸颊、前臂的掌侧表面和手的掌侧表面使用脊状圆柱形鼓进行调整,该鼓以60 rpm旋转120 s。尽管所测试的皮肤表面之间的持续时间或生动性没有差异,但与脸颊和前臂相比,手部的触觉MAE被报告为两倍,彼此之间没有显着差异。这表明无毛皮肤和毛囊中的FA I单位和/或多毛皮肤中的FA I和field单位有助于触觉MAE。
  • 【倾斜后效应中对比极性选择性的测试。】 复制标题 收藏 收藏
    DOI:10.1068/p080523 复制DOI
    作者列表:Magnussen S,Kurtenbach W
    BACKGROUND & AIMS: :The tilt aftereffect (TAE) was studied with adapting and test stimuli consisting of black or white bars (experiment 1), and of luminance edges (experiment 2). Both experiments failed to demonstrate selectivity of the TAE to the polarity of luminance contrast.
    背景与目标: : 使用由黑色或白色条 (实验1) 和亮度边缘 (实验2) 组成的适应和测试刺激研究了倾斜后效 (TAE)。两个实验都未能证明TAE对亮度对比度极性的选择性。
  • 【主要视觉皮层中倾斜后效的可能机制: 借助简单的计算模型进行的批判性分析。】 复制标题 收藏 收藏
    DOI:10.1016/j.visres.2008.04.002 复制DOI
    作者列表:Ursino M,Magosso E,Cuppini C
    BACKGROUND & AIMS: :A mathematical model of orientation selectivity in a single hypercolumn of the primary visual cortex developed in a previous work [Ursino, M., & La Cara, G.-E. (2004). Comparison of different models of orientation selectivity based on distinct intracortical inhibition rules. Vision Research, 44, 1641-1658] was used to analyze the possible mechanisms underlying tilt aftereffect (TAE). Two alternative models are considered, based on a different arrangement of intracortical inhibition (an anti-phase model in which inhibition is in phase opposition with excitation, and an in-phase model in which inhibition has the same phase arrangement as excitation but wider orientation selectivity). Different combinations of parameter changes were tested to explain TAE: a threshold increase in excitatory and inhibitory cortical neurons (fatigue), a decrease in intracortical excitation, an increase or a decrease in intracortical inhibition, a decrease in thalamo-cortical synapses. All synaptic changes were calculated on the basis of Hebbian (or anti-Hebbian) rules. Results demonstrated that the in-phase model accounts for several literature results with different combinations of parameter changes requiring: (i) a depressive mechanism to neurons with preferred orientation close to the adaptation orientation (fatigue of excitatory cortical neurons, and/or depression of thalamo-cortical synapses directed to excitatory neurons, and/or depression of intracortical excitatory synapses); (ii) a facilitatory mechanism to neurons with preferred orientation far from the adaptation orientation (fatigue of inhibitory cortical neurons, and/or depression of thalamo-cortical synapses directed to inhibitory neurons, and/or depression of intracortical inhibitory synapses). By contrast, the anti-phase model appeared less suitable to explain experimental data.
    背景与目标: : 在先前的工作 [Ursino,M.和La Cara,G.-E] 中建立的初级视觉皮层的单个超列中定向选择性的数学模型。基于不同的皮质内抑制规则的不同定向选择性模型的比较。视觉研究,44,1641-1658] 用于分析倾斜后效 (TAE) 的可能机制。考虑了两种替代模型,基于皮质内抑制的不同排列 (反相模型,其中抑制与激发相反,而同相模型,其中抑制具有与激发相同的相位排列,但方向选择性较宽)。测试了参数变化的不同组合以解释TAE: 兴奋性和抑制性皮质神经元的阈值增加 (乏力),皮质内兴奋的减少,皮质内抑制的增加或减少,丘脑-皮质突触的减少。所有突触变化均根据Hebbian (或反Hebbian) 规则计算。结果表明,同相模型解释了几种文献结果,其参数变化的不同组合需要 :( i) 对具有接近适应方向的首选方向的神经元的抑制机制 (兴奋性皮质神经元乏力和/或丘脑-皮质突触的抑制针对兴奋性神经元,和/或皮质内兴奋性突触的抑制); (ii) 对神经元的促进机制,其优选的方向远离适应方向 (抑制性皮质神经元乏力,和/或针对抑制性神经元的丘脑-皮质突触的抑制,和/或皮质内抑制性突触的抑制)。相比之下,反相模型似乎不太适合解释实验数据。
  • 7 Storage of an oculomotor motion aftereffect. 复制标题 收藏 收藏

    【动眼运动后效的存储。】 复制标题 收藏 收藏
    DOI:10.1016/j.visres.2006.09.030 复制DOI
    作者列表:Watamaniuk SN,Heinen SJ
    BACKGROUND & AIMS: :Adaptation to motion produces a motion aftereffect (MAE), where illusory, oppositely-directed motion is perceived when viewing a stationary image. A common hypothesis for motion adaptation is that it reflects an imbalance of activity caused by neuronal fatigue. However, the perceptual MAE exhibits storage, in that the MAE appears even after a prolonged period of darkness is interposed between the adapting stimulus and the test, suggesting that fatigue cannot explain the perceptual MAE. We asked whether neural fatigue was a viable explanation for the oculomotor MAE (OMAE) by testing if the OMAE exhibits storage. Human observers were adapted with moving, random-dot cinematograms. Following adaptation, they generated an oculomotor MAE (OMAE), with both pursuit and saccadic components. The OMAE occurred in the presence of a visual test stimulus, but not in the dark. When the test stimulus was introduced after the dark period, the OMAE reappeared, analogous to perceptual MAE storage. The results suggest that fatigue cannot explain the OMAE, and that visual stimulation is necessary to elicit it. We propose a model in which adaptation recalibrates the motion-processing network by adjusting the weights of the inputs to neurons in the middle-temporal (MT) area.
    背景与目标: : 对运动的适应会产生运动后效 (MAE),在观看静止图像时会感觉到虚幻的,相反方向的运动。运动适应的一个常见假设是,它反映了神经元乏力引起的活动失衡。然而,知觉MAE表现出存储性,因为即使在适应刺激和测试之间插入了长时间的黑暗之后,MAE也会出现,这表明乏力无法解释知觉MAE。我们通过测试OMAE是否表现出储存来询问神经乏力是否是动眼MAE (OMAE) 的可行解释。人类观察者采用了移动的随机点电影图。适应后,他们产生了动眼运动MAE (OMAE),其中包括追求和扫视成分。OMAE发生在视觉测试刺激的情况下,但不是在黑暗中。当测试刺激在黑暗时期之后引入时,OMAE再次出现,类似于感知的MAE存储。结果表明乏力不能解释OMAE,并且视觉刺激是引起它的必要条件。我们提出了一个模型,在该模型中,自适应通过调整中时间 (MT) 区域神经元的输入权重来重新校准运动处理网络。
  • 【方向后效应由局部运动检测器的适应驱动。】 复制标题 收藏 收藏
    DOI:10.1016/j.visres.2006.08.026 复制DOI
    作者列表:Curran W,Clifford CW,Benton CP
    BACKGROUND & AIMS: :The processing of motion information by the visual system can be decomposed into two general stages; point-by-point local motion extraction, followed by global motion extraction through the pooling of the local motion signals. The direction aftereffect (DAE) is a well known phenomenon in which prior adaptation to a unidirectional moving pattern results in an exaggerated perceived direction difference between the adapted direction and a subsequently viewed stimulus moving in a different direction. The experiments in this paper sought to identify where the adaptation underlying the DAE occurs within the motion processing hierarchy. We found that the DAE exhibits interocular transfer, thus demonstrating that the underlying adapted neural mechanisms are binocularly driven and must, therefore, reside in the visual cortex. The remaining experiments measured the speed tuning of the DAE, and used the derived function to test a number of local and global models of the phenomenon. Our data provide compelling evidence that the DAE is driven by the adaptation of motion-sensitive neurons at the local-processing stage of motion encoding. This is in contrast to earlier research showing that direction repulsion, which can be viewed as a simultaneous presentation counterpart to the DAE, is a global motion process. This leads us to conclude that the DAE and direction repulsion reflect interactions between motion-sensitive neural mechanisms at different levels of the motion-processing hierarchy.
    背景与目标: : 视觉系统对运动信息的处理可以分解为两个一般阶段; 逐点本地运动提取,然后通过本地运动信号的汇集进行全局运动提取。方向后效 (DAE) 是一种众所周知的现象,其中先前对单向移动模式的适应导致在适应的方向和随后观察到的在不同方向上移动的刺激之间的放大的感知方向差。本文中的实验旨在确定DAE的适应在运动处理层次结构中发生的位置。我们发现DAE表现出眼间转移,因此表明潜在的适应神经机制是双眼驱动的,因此必须驻留在视觉皮层中。其余实验测量了DAE的速度调整,并使用派生函数测试了该现象的许多局部和全局模型。我们的数据提供了令人信服的证据,表明DAE是由运动编码的局部处理阶段的运动敏感神经元的适应驱动的。这与先前的研究相反,该研究表明,方向排斥 (可以被视为DAE的同时呈现对应物) 是一个全局运动过程。这使我们得出结论,DAE和方向排斥反映了运动处理层次结构不同级别的运动敏感神经机制之间的相互作用。
  • 9 Aftereffect of perceived regularity. 复制标题 收藏 收藏

    【感知规律性的后遗症。】 复制标题 收藏 收藏
    DOI:10.1167/13.8.18 复制DOI
    作者列表:Ouhnana M,Bell J,Solomon JA,Kingdom FA
    BACKGROUND & AIMS: :Regularity is a ubiquitous feature of the visual world. We demonstrate that regularity is an adaptable visual dimension: The perceived regularity of a pattern is reduced following adaptation to a pattern with a similar or greater degree of regularity. Stimuli consisted of 7×7 element arrays arranged on square grids presented in a circular aperture. The position of each element was randomly jittered from its baseline position by an amount that determined its degree of irregularity. The elements of the pattern consisted of dark Gaussian blobs (GBs), difference of Gaussians (DOGs), or random binary patterns (RBPs). Observers adapted for 60 s to either a single pattern or a pair of patterns with particular regularities, and the perceived regularities of subsequently presented test patterns were measured using a conventional staircase matching procedure. We found that the regularity aftereffect (RAE) was unidirectional: Adaptation only caused test patterns to appear less regular. We also found that RAEs transferred from GB adaptors to both DOG and RBP test patterns and from DOG and RBP adaptors to GB patterns. We suggest that regularity is coded by the peakedness in the distribution of spatial-frequency channel responses across scale, and that the RAE is a result of a flattening of this distribution by adaptation. Thus, the RAE may be a consequence of contrast normalization, and an example of norm-based coding where irregularity is the norm.
    背景与目标: : 规律性是视觉世界普遍存在的特征。我们证明了规律性是一种可适应的视觉维度: 随着适应具有相似或更大规律性的图案,图案的感知规律性会降低。刺激由排列在圆形孔径中呈现的方形网格上的7 × 7元素阵列组成。每个元素的位置从其基线位置随机抖动确定其不规则程度的量。模式的元素由暗高斯斑点 (gb),高斯差 (狗) 或随机二进制模式 (rbp) 组成。观察者适应了60 s的单个模式或一对具有特定规律性的模式,并使用常规的楼梯匹配程序测量了随后呈现的测试模式的感知规律性。我们发现规律性后效 (RAE) 是单向的: 适应只会导致测试模式显得不太规则。我们还发现rae从GB适配器转移到DOG和RBP测试模式,从DOG和RBP适配器转移到GB模式。我们建议,规则性是通过跨尺度的空间频率信道响应分布的峰度来编码的,并且RAE是通过适应使该分布变平的结果。因此,RAE可能是对比度归一化的结果,并且是基于规范的编码的示例,其中不规则性是规范。
  • 【抑制视动性眼球震颤后黑暗中的眼球震颤: 运动后效和视网膜余像的相互作用。】 复制标题 收藏 收藏
    DOI:10.1007/s00221-014-3971-4 复制DOI
    作者列表:Chen CC,Huang MY,Weber KP,Straumann D,Bockisch CJ
    BACKGROUND & AIMS: :The afternystagmus that occurs in the dark after gaze fixation during optokinetic stimulation is directed in the opposite direction relative to the previous optokinetic stimulus. The mechanism responsible for such afternystagmus after suppression of optokinetic nystagmus (ASOKN) is unclear. Several hypotheses have been put forward to explain it, but none is conclusive. We hypothesized that ASOKN is driven by the interaction of two mechanisms: (1) motion-aftereffect (MAE)-induced eye movements and (2) retinal afterimages (RAIs) produced by fixation during the suppression of optokinetic nystagmus (OKN). We examined the correlation among ASOKN, MAE-induced eye movements, and RAIs in healthy subjects. Adapting stimuli consisted of moving random dot patterns and a fixation spot and their brightness was adjusted to induce different RAI durations. Test patterns were a stationary random dot pattern (to test for the presence of a MAE), a dim homogeneous background (to test for MAE driven eye movements), and a black background (to test for ASOKN and RAIs). MAEs were reported by 16 out of 17 subjects, but only 7 out of 17 subjects demonstrated MAE-induced eye movements. Importantly, ASOKN was only found when these seven subjects reported a RAI after suppression of OKN. Moreover, the duration of ASOKN was longer for high-brightness stimuli compared with low-brightness stimuli, just as RAIs persist longer with increasing brightness. We conclude that ASOKN results from the interaction of MAE-induced eye movements and RAIs.
    背景与目标: : 视动刺激过程中注视固定后在黑暗中发生的眼球震颤相对于先前的视动刺激方向相反。抑制视动性眼球震颤 (ASOKN) 后引起这种眼球震颤的机制尚不清楚。已经提出了几个假设来解释它,但没有一个是决定性的。我们假设ASOKN是由两种机制的相互作用驱动的 :( 1) 运动后效 (MAE) 诱导的眼球运动和 (2) 在抑制视动性眼球震颤 (OKN) 期间通过固定产生的视网膜残像 (RAIs)。我们检查了健康受试者中ASOKN,MAE诱导的眼球运动和rai之间的相关性。适应刺激由移动的随机点图案和固定点组成,并调整其亮度以诱导不同的RAI持续时间。测试模式是固定的随机点模式 (测试MAE的存在),昏暗的均匀背景 (测试MAE驱动的眼球运动) 和黑色背景 (测试ASOKN和RAIs)。17名受试者中有16名报告了MAEs,但17名受试者中只有7名表现出MAE诱导的眼球运动。重要的是,只有当这七个受试者在抑制OKN后报告RAI时,才发现ASOKN。此外,与低亮度刺激相比,高亮度刺激的ASOKN持续时间更长,就像RAIs随着亮度增加而持续的时间更长一样。我们得出的结论是,ASOKN是由MAE引起的眼球运动和RAIs的相互作用引起的。
  • 【触觉手指间视在运动中的方向重映射: 运动后效研究。】 复制标题 收藏 收藏
    DOI:10.1007/s00221-011-2936-0 复制DOI
    作者列表:Kuroki S,Watanabe J,Mabuchi K,Tachi S,Nishida S
    BACKGROUND & AIMS: :Tactile motion provides critical information for perception and manipulation of objects in touch. Perceived directions of tactile motion are primarily defined in the environmental coordinate, which means they change drastically with body posture even when the same skin sensors are stimulated. Despite the ecological importance of this perceptual constancy, the sensory processing underlying tactile directional remapping remains poorly understood. The present study psychophysically investigated the mechanisms underlying directional remapping in human tactile motion processing by examining whether finger posture modulates the direction of the tactile motion aftereffect (MAE) induced by inter-finger apparent motions. We introduced conflicts in the adaptation direction between somatotopic and environmental spaces by having participants change their finger posture between adaptation and test phases. In a critical condition, they touched stimulators with crossed index and middle fingers during adaptation but with uncrossed fingers during tests. Since the adaptation effect was incongruent between the somatotopic and environmental spaces, the direction of the MAE reflects the coordinate of tactile motion processing. The results demonstrated that the tactile MAE was induced in accordance with the motion direction determined by the environmental rather than the somatotopic space. In addition, it was found that though the physical adaptation of the test fingers was not changed, the tactile MAE disappeared when the adaptation stimuli were vertically aligned or when subjective motion perception was suppressed during adaptation. We also found that the tactile MAE, measured with our procedure, did not transfer across different hands, which implies that the observed MAEs mainly reflect neural adaptations occurring within sensor-specific, tactile-specific processing. The present findings provide a novel behavioral method to analyze the neural representation for directional remapping of tactile motion within tactile sensory processing in the human brain.
    背景与目标: : 触觉运动为感知和操纵触摸物体提供了关键信息。触觉运动的感知方向主要是在环境坐标中定义的,这意味着即使在刺激相同的皮肤传感器时,它们也会随着身体姿势的变化而急剧变化。尽管这种感知恒定性具有生态重要性,但触觉方向重映射的感官处理仍知之甚少。本研究通过检查手指姿势是否调节手指间表观运动引起的触觉运动后效 (MAE) 的方向,从心理上研究了人类触觉运动处理中方向重映射的潜在机制。通过让参与者在适应阶段和测试阶段之间改变手指姿势,我们引入了躯体和环境空间之间适应方向上的冲突。在危急情况下,他们在适应过程中接触了食指和中指交叉的刺激器,但在测试过程中没有交叉的手指。由于适应效果在躯体和环境空间之间不一致,因此MAE的方向反映了触觉运动处理的坐标。结果表明,触觉MAE是根据环境而不是躯体空间确定的运动方向诱发的。此外,发现尽管没有改变测试手指的物理适应,但当适应刺激垂直对齐或在适应过程中抑制主观运动感知时,触觉MAE消失了。我们还发现,用我们的程序测量的触觉MAE不会跨不同的手转移,这意味着观察到的MAE主要反映了在特定于传感器,特定于触觉的处理中发生的神经适应。本发现提供了一种新颖的行为方法来分析神经表示,以在人脑的触觉感觉处理中进行触觉运动的方向重映射。
  • 【[周期性刺激后效应中兔感觉运动皮层神经元的微量节律再现特征]。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Kopytova FV
    BACKGROUND & AIMS: Trace rhythm recruitment (TRR)--CR analogue to time was studied appearing in response to prolonged electrocutaneous stimulation of the forelimb of the alert rabbit with the frequency 0.5-1-2 Hz. The activity was recorded of 180 cells of the sensorimotor cortex before (80) and after (100) periodical stimulation during 10-20 min. The first series of rhythmic stimulation led to a short-term TRR of the stimulation frequency, the following series formed a clear TRR, preserved for several days. The possibility was revealed of "relearning" of neurones at stimulation rhythm change. The ability of TRR phenomenon of extinguishment, prolonged preservation and reproduction of traces, "relearning" brings it nearer to the processes, analogous to the temporal connection. The ability to reveal distinctly and to quantitatively estimate the characteristics of the applied stimulus fixated by the neurones, makes this model perspective for comparable study of the memory traces at the neuronal level in the animals of various ages.

    背景与目标: 研究了对时间的痕量节律募集 (TRR)-CR类似物,以0.5-1-2Hz的频率对机敏兔前肢进行长时间的皮肤电刺激。在10-20分钟的周期性刺激之前 (80) 和之后 (100) 记录感觉运动皮层的180细胞的活性。第一系列有节奏的刺激导致了刺激频率的短期TRR,随后的一系列形成了清晰的TRR,保存了几天。揭示了在刺激节律改变时神经元 “重新学习” 的可能性。TRR现象的熄灭,长时间保存和复制痕迹的能力,“重新学习” 使其更接近过程,类似于时间连接。能够清晰地揭示并定量估计神经元固定的所施加刺激的特征,使该模型具有对不同年龄的动物在神经元水平上的记忆痕迹进行可比研究的观点。
  • 【多感官同时重新校准: 在没有反证的情况下储存后效。】 复制标题 收藏 收藏
    DOI:10.1007/s00221-011-2976-5 复制DOI
    作者列表:Machulla TK,Di Luca M,Froehlich E,Ernst MO
    BACKGROUND & AIMS: :Recent studies show that repeated exposure to an asynchrony between auditory and visual stimuli shifts the point of subjective simultaneity. Usually, the measurement stimuli used to assess this aftereffect are interleaved with short re-exposures to the asynchrony. In a first experiment, we show that the aftereffect declines during measurement in spite of the use of re-exposures. In a second experiment, we investigate whether the observed decline is either due to a dissipation of the aftereffect with the passage of time, or the result of using measurement stimuli with a distribution of asynchronies different from the exposure stimulus. To this end, we introduced a delay before measuring the aftereffects and we compared the magnitude of the aftereffect with and without delay. We find that the aftereffect does not dissipate during the delay but instead is stored until new sensory information in the form of measurement stimuli is presented as counterevidence (i.e., stimuli with an asynchrony that differs from the one used during exposure).
    背景与目标: : 最近的研究表明,反复暴露于听觉和视觉刺激之间的不同步状态会改变主观同时性。通常,用于评估这种后效的测量刺激与短暂的不同步再暴露交织在一起。在第一个实验中,我们表明尽管使用了再曝光,但在测量过程中后效会下降。在第二个实验中,我们研究观察到的下降是由于后效随着时间的流逝而消散,还是使用具有与暴露刺激不同的异步分布的测量刺激的结果。为此,我们在测量后效之前引入了一个延迟,并比较了有和没有延迟的后效的大小。我们发现,后效不会在延迟期间消散,而是被存储,直到以测量刺激形式的新感官信息被呈现为反证 (即,具有与暴露期间使用的不同步刺激不同的不同步刺激)。
  • 【1-硝基吖啶的细胞毒性和抗肿瘤活性是其链间DNA交联的后效。】 复制标题 收藏 收藏
    DOI: 复制DOI
    作者列表:Pawlak K,Pawlak JW,Konopa J
    BACKGROUND & AIMS: :To determine whether the toxic effects and changes in many cell functions caused by antitumor 1-nitroacridines are related to their enzymatically mediated covalent interstrand DNA cross-linking (J. Konopa, J. W. Pawlak, and K. Pawlak. Chem.-Biol. Interact., 43: 175-197, 1983), the cross-linking potency of the derivatives with structural modifications in position 9 of the acridine nucleus was estimated as their in vitro threshold concentrations (0.3 to 4.5 microM), beyond which the first interstrand DNA cross-links could be detected in DNA of cultured HeLa S3 cells with a polyethylene glycol 6000-Dextran T500 assay. Statistically significant (p less than 0.05) correlations exist between the cross-linking potency of 1-nitroacridines and their in vivo antitumor activity and toxicity against mice with Sarcoma 180 tumors in solid form (3 to 1065 mumol/kg of body weight), as well as their in vitro cytotoxicity against cultured HeLa or HeLa S3 cells (0.0005 to 7.2 microM), indicating that the interstrand DNA cross-linking potency might be one of primary determinants of in vivo and in vitro biological activity of 1-nitroacridine antineoplastic drugs. Susceptibility of the parent agents to reduction does not appear to be a rate-limiting factor of DNA cross-linking potency of 1-nitroacridines and their metabolic transformations (J. W. Pawlak, and J. Konopa. Biochem. Pharmacol., 28: 3391-3402, 1979), because no significant differences were observed among the agents with respect to their polarographic half-wave potentials estimated under anaerobic conditions.
    背景与目标: : 确定抗肿瘤1-硝基吖啶引起的毒性作用和许多细胞功能的变化是否与其酶介导的共价链间DNA交联有关 (J. Konopa,J. W. Pawlak和K. Pawlak. Chem.-Biol. Interact.,43: 175-197,1983),以其体外阈值浓度 (0.3至4.5微米) 估算了在吖啶核9位具有结构修饰的衍生物的交联效力,除此之外,可以用聚乙二醇6000-葡聚糖T500测定在培养的helas3细胞的DNA中检测到第一链间DNA交联。1-硝基吖啶的交联效力与其体内抗肿瘤活性和对实体形式 (3至1065 mumol/kg体重) 肉瘤180小鼠的毒性之间存在统计学意义 (p <0.05),以及它们对培养的HeLa或HeLa S3细胞的体外细胞毒性 (0.0005至7.2微米),表明链间DNA交联效力可能是1-硝基吖啶抗肿瘤药物的体内和体外生物活性的主要决定因素之一。亲本剂对还原的敏感性似乎不是1-硝基吖啶及其代谢转化的DNA交联效力的限速因素 (J. W. Pawlak和J. Konopa. Biochem. Pharmacol.,28: 3391-3402,1979),因为在厌氧条件下估计的极谱半波电势方面,在试剂之间未观察到显着差异。
  • 【一种基于识别对比度阈值的新型人脸后效】 复制标题 收藏 收藏
    DOI:10.1016/j.visres.2010.06.005 复制DOI
    作者列表:Oruç I,Barton JJ
    BACKGROUND & AIMS: :Previously, repulsive perceptual-shift face aftereffects have been reported. Here, we introduce a novel face adaptation method involving changes in contrast thresholds for face recognition. We find non-monotonic changes for adapted faces, with facilitation at short and suppression at long durations. Thresholds for unadapted faces were unaffected at short but elevated at long durations, more than those for the adapted face. A population-coding model showed that selective suppression of adapted representations cannot explain repulsive perceptual-bias aftereffects. The findings indicate greater complexity to adaptation, with facilitation, suppression, lateral inhibition of unadapted representations, and additional perceptual factors at long durations.
    背景与目标: : 以前,已经报道了令人厌恶的感知移位面部后效。在这里,我们介绍了一种新颖的人脸自适应方法,该方法涉及人脸识别对比度阈值的变化。我们发现适应的面孔具有非单调变化,在短时间内具有促进作用,在长时间内具有抑制作用。短时间不影响未适应面孔的阈值,但长时间不影响阈值,比适应面孔的阈值更大。人口编码模型表明,对适应性表示的选择性抑制不能解释令人反感的感知偏差后效。研究结果表明,适应的复杂性更高,包括促进,抑制,对不适应的表示的横向抑制以及长时间的其他感知因素。

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