Abstract：
:The ability to locomote is a defining characteristic of all animals. Yet, all but the most trivial forms of navigation are poorly understood. Here we report and discuss the analytical results of an in-depth study of a simple navigation problem. In principle, there are two strategies for navigating a straight course. One is to use an external directional reference and to continually reorient with reference to it. The other is to monitor body rotations from internal sensory information only. We showed previously that, at least for simple representations of locomotion, the first strategy will enable an animal or mobile agent to move arbitrarily far away from its starting point, but the second strategy will not do so, even after an infinite number of steps. This paper extends and generalizes the earlier results by demonstrating that these findings are true even when a very general model of locomotion is used. In this general model, error components within individual steps are not independent, and directional errors may be biased. In the absence of a compass, the expected path of a directed walk in general approximates a logarithmic spiral. Some examples are given to illustrate potential applications of the quantitative results derived here. Motivated by the analytical results developed in this work, a nomenclature for directed walks is proposed and discussed. Issues related to path integration in mammals and robots, and measuring the curvature of a noisy path are also addressed using directed walk theory.
journal_name
Biol Cybernjournal_title
Biological cyberneticsauthors
Cheung A,Zhang S,Stricker C,Srinivasan MVdoi
10.1007/s00422-008-0251-zsubject
Has Abstractpub_date
2008-09-01 00:00:00pages
197-217issue
3eissn
0340-1200issn
1432-0770journal_volume
99pub_type
杂志文章abstract：:Motion repulsion is the perceived enlargement of the angle between the directions of motion of two transparently moving patterns. An explanation of this illusion has long been sought for in the neural circuitry of the brain. We show that motion repulsion already arises from the statistical properties of the motion tra...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-005-0556-0
更新日期：2005-04-01 00:00:00
abstract：:It has been suggested that the mammalian memory system has both familiarity and recollection components. Recently, a high-capacity network to store familiarity has been proposed. Here we derive analytically the optimal learning rule for such a familiarity memory using a signal- to-noise ratio analysis. We find that in...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-008-0275-4
更新日期：2009-01-01 00:00:00
abstract：:Neurons transmit information as action potentials or spikes. Due to the inherent randomness of the inter-spike intervals (ISIs), probabilistic models are often used for their description. Cumulative damage (CD) distributions are a family of probabilistic models that has been widely considered for describing time-relat...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-015-0651-9
更新日期：2015-10-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00337450
更新日期：1979-02-02 00:00:00
abstract：:In this article, we present a neurologically motivated computational architecture for visual information processing. The computational architecture's focus lies in multiple strategies: hierarchical processing, parallel and concurrent processing, and modularity. The architecture is modular and expandable in both hardwa...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0597-3
更新日期：2014-06-01 00:00:00
abstract：:The previous companion paper describes the initial (seed) schema architecture that gives rise to the observed prey-catching behavior. In this second paper in the series we describe the fundamental adaptive processes required during learning after lesioning. Following bilateral transections of the hypoglossal nerve, an...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-005-0014-z
更新日期：2005-12-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-001-0298-6
更新日期：2002-04-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-012-0530-6
更新日期：2012-11-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00202449
更新日期：1990-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-014-0621-7
更新日期：2014-12-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-003-0422-x
更新日期：2003-09-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050362
更新日期：1997-07-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/BF00201441
更新日期：1990-01-01 00:00:00
abstract：:A fundamental problem in neuroscience, to which Prof. Segundo has made seminal contributions, is to understand how action potentials represent events in the external world. The aim of this paper is to review the issue of neural coding in the context of the rodent whiskers, an increasingly popular model system. Key iss...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-008-0290-5
更新日期：2009-06-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00202455
更新日期：1990-01-01 00:00:00
abstract：:According to modern views of the cerebellum in motor control, each cerebellar functional unit, or microzone, learns how to execute predictive and coordinative control, based on long-term depression of the granule cell-Purkinje cell synapses. In the present paper, in light of recent experimental and theoretical studies...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050462
更新日期：1998-08-01 00:00:00
abstract：:The conductance-based refractory density (CBRD) approach is an efficient tool for modeling interacting neuronal populations. The model describes the firing activity of a statistical ensemble of uncoupled Hodgkin-Huxley-like neurons, each receiving individual Gaussian noise and a common time-varying deterministic input...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-017-0727-9
更新日期：2017-12-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220170005
更新日期：2001-01-01 00:00:00
abstract：:We develop a novel optimal control algorithm to change the phase of an oscillator using a minimum energy input, which also minimizes the oscillator's transversal distance to the uncontrolled periodic orbit. Our algorithm uses a two-dimensional reduction technique based on both isochrons and isostables. We develop a no...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-018-0764-z
更新日期：2019-04-01 00:00:00
abstract：:The present paper considers the relation between the shape of a triangle and probability of its recognition. An effect of triangle size on perception of its shape is examined in the first experiment. In the second the loci of eye fixations during triangle recognition task are recorded and analysed. A simulation model ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00363955
更新日期：1988-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050435
更新日期：1998-04-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00453373
更新日期：1981-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00201489
更新日期：1995-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00198768
更新日期：1989-01-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/BF00387211
更新日期：1982-01-01 00:00:00
abstract：:The generation of informational sequences and their reorganization or reshaping is one of the most intriguing subjects for both neuroscience and the theory of autonomous intelligent systems. In spite of the diversity of sequential activities of sensory, motor, and cognitive neural systems, they have many similarities ...
journal_title：Biological cybernetics
pub_type： 杂志文章,评审
doi：10.1007/s00422-006-0121-5
更新日期：2006-12-01 00:00:00
abstract：:Spike-timing-dependent plasticity (STDP) determines the evolution of the synaptic weights according to their pre- and post-synaptic activity, which in turn changes the neuronal activity. In this paper, we extend previous studies of input selectivity induced by (STDP) for single neurons to the biologically interesting ...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-009-0319-4
更新日期：2009-08-01 00:00:00
abstract：:Simulation results of bistable perception due to ambiguous visual stimuli are presented which are obtained with a behavioral nonlinear dynamics model using perception-attention-memory coupling. This model provides an explanation of recent experimental results of Gao et al. (Cogn Process 7:105-112, 2006a) and it suppor...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s00422-010-0388-4
更新日期：2010-09-01 00:00:00
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journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220050561
更新日期：1999-09-01 00:00:00
abstract：:Based on a complexity analysis of mutual information transmission of EEG developed by us [Xu J, Liu Z, Liu R, Yang Q (1997) Physica D 106: 363-374], dynamic processes of the complexity of mutual information transmission in human brains were studied. To diminish possible problems due to coarse graining preprocessing, s...
journal_title：Biological cybernetics
pub_type： 杂志文章
doi：10.1007/s004220000158
更新日期：2000-10-01 00:00:00
