Self-organisation in dynamical systems: a limiting result

There is presently considerable interest in the phenomenon of “self-organisation” in dynamical systems. The rough idea of self-organisation is that a structure appears “by itself” in a dynamical system, with reasonably high probability, in a reasonably short time, with no help from a special initial state, or interaction with an external system. What is often missed, however, is that the standard evolutionary account of the origin of multi-cellular life fits this definition, so that higher living organisms are also products of self-organisation. Very few kinds of object can self-organise, and the question of what such objects are like is a suitable mathematical problem. Extending the familiar notion of algorithmic complexity into the context of dynamical systems, we obtain a notion of “dynamical complexity”. A simple theorem then shows that only objects of very low dynamical complexity can self organise, so that living organisms must be of low dynamical complexity. On the other hand, symmetry considerations suggest that living organisms are highly complex, relative to the dynamical laws, due to their large size and high degree of irregularity. In particular, it is shown that since dynamical laws operate locally, and do not vary across space and time, they cannot produce any specific large and irregular structure with high probability in a short time. These arguments suggest that standard evolutionary theories of the origin of higher organisms are incomplete.     

Timing, clocks, and dynamical systems.

Theoretical and experimental issues for our understanding of the timing of motor acts are reviewed, contrasting stochastic and dynamic timing models. It is argued that the theory of dynamical systems and, in particular, of limit cycle attractors, provides a unified framework within which these issues can be appreciated. The strength of stochastic timing models in the domain of absolute timing is contrasted with the strength of dynamic timing models in the domain of relative timing, the unification of the two domains being currently under way. It is further argued that accounts of timing must examine the interrelation between timing and other levels of processing involved in movement generation, in particular, the representation of spatial aspects of movement and the control of movement. The emergence of discrete event structure in timing skills is discussed from a dynamical systems perspective. Finally, the understanding of the timing structure of discrete movement is raised as a further challenge for future work.     

A dynamical systems approach to manual tracking performance

Manual tracking performance was investigated from the perspective of dynamical systems theory. The authors manipulated the type of visual display, the control system dynamics, and the frequency of the sinusoidal input signal to examine couplings with various phases between the visual signal and control movements. Analyses of the system output amplitude ratio and relative phase showed that participants (N = 24) performed poorly with 90 degrees relative phase coupling. All the couplings became less stable as the movement frequency increased. The authors developed an adaptive oscillator model with linear damping to describe the coupled system consisting of the human performer, the visual display, and the control system dynamics. A geometric account of the stability of performance at different relative phases is also presented.     

Cognitive control of real-time event-driven systems

The paper discusses the development of cognitive skills in control of real-time, event-driven systems with long time lag. Using simulators of ship steering, and based on thinking-aloud protocol experiments, it is shown that unskilled persons may devote most of the initial period of learning control skills to understanding the causal behavior of the human-machine interface. Experts employ goal-oriented strategies, planning from a relatively global view-point. A possible explanation for the development of cognitive strategies is presented to account for the gathering of information about the control interface, the acquisition of various kinds of strategies, and the learning of control skills for real-time, event-driven systems with long time lag. A computer simulation model is presented that merges cognitive and control theory models, and that simulates the process of strategy development.     

Cognitive systems struggling for word order

We argue that the grammatical diversity observed among the world’s languages emerges from the struggle between individual cognitive systems trying to impose their preferred structure on human language. We investigate the cognitive bases of the two most common word orders in the world’s languages: SOV (Subject–Object–Verb) and SVO. Evidence from language change, grammaticalization, stability of order, and theoretical arguments, indicates a syntactic preference for SVO. The reason for the prominence of SOV languages is not as clear. In two gesture-production experiments and one gesture comprehension experiment, we show that SOV emerges as the preferred constituent configuration in participants whose native languages (Italian and Turkish) have different word orders. We propose that improvised communication does not rely on the computational system of grammar. The results of a fourth experiment, where participants comprehended strings of prosodically flat words in their native language, shows that the computational system of grammar prefers the orthogonal Verb–Object orders.     

Learning the cascade juggle: a dynamical systems analysis

How beginning jugglers discover the temporal constraints governing the juggling workspace while learning to juggle three balls in a cascade pattern was the subject of this investigation. On the basis of previous theoretical and experimental work on expert jugglers, we proposed a three-stage model of the learning process, for which objective evidence was sought. The first stage consists of learning to accommodate the real-time requirements of juggling, as expressed in Shannon's equation of juggling, which states that, averaged over time, the cycle time of the hands should be a fixed proportion of the cycle time of the balls. The second stage of learning consists of discovering the primary frequency lock of.75 between the shorter term dynamical regime underlying the repetitive subtask of transporting a ball and the longer term dynamical regime underlying the total hand loop cycle. The third and last stage of learning consists of discovering the principles of frequency modulation from.75 to lower (averaged) values of the proportion of time that a hand carries a ball during the total hand cycle time. Twenty subjects were taught to juggle three balls in a cascade pattern. Ten subjects were trained with the aid of an instructor and a metronome, and 10 with the instructor only. The metronome proved to be of no particular additional help, but the timing results obtained were in agreement with the proposed three stages of learning. The picture that emerged from this study was that learning a new motor skill involves the discovery of invariance's or fixed points in the perceptual-motor workspace associated with that skill, from which excursions can be made and the skill further refined. Because these fixed points afford stability of operation, discovering them logically and factually precedes the acquisition of the functional adaptability and flexibility of operation ("flair") inherent to frequency modulation.     

Tools for connectionist modeling: The dynamical systems methodology

Some understanding of dynamical systems is essential to achieving competency in connectionist models. This mathematical background can be acquired either through a rigorous set of upper undergraduate and/or graduate formal courses or via disciplined self-teaching. As part of developing a course in connectionism, we feel that although certain very basic mathematical tools are most appropriately learned in their “pure” form (i.e., from mathematics textbooks and courses), more advanced exposure to dynamical systems theory can be given in the context of an introduction to connectionism. Students thus learn to write connectionist simulations by first writing programs for simulating arbitrary dynamical systems, then using them to learn some aspects of dynamical systems in general by simulating some special cases, and finally applying this technique to connectionist models of increasing complexity.     

Propositions as Cognitive Acts

Synthese - The paper reviews the central components of the cognitive theory of propositions and explains both its empirical advantages for theories of language and mind and its foundational...     

A dynamical systems analysis of spontaneous movements in newborn infants

The authors evaluated the characteristics of infants' spontaneous movements by using dynamical systems analysis. Participants were 6 healthy 1-month-old full-term newborn infants (3 males, 3 females). They used a triaxial accelerometer to measure limb acceleration in 3-dimensional space. Acceleration signals were recorded during 200 s from the right wrist when the infant was in an active alert state and lying supine (sampling rate 200 Hz). and was stored in the system's memory. Digitized data were transferred to a PC for subsequent processing with analysis software. The acceleration time series data were analyzed linearly and nonlinearly. Nonlinear time series analysis suggested that the infants' spontaneous movements are characterized by a nonlinear chaotic dynamics with 5 or 6 embedding dimensions. The production of infants'spontaneous movements involves chaotic dynamic systems that are capable of generating voluntary skill movements.     

A dynamical systems interpretation of a dimensional model of emotion

The dimensional structure of emotion was investigated using self reports of induced mood and idiographic and nomothetic analyses. Subjects attended four experimental sessions during which an array of affective states was induced via auditory, visual, and imaginal channels. For each of 118 stimulus events, subjects self-rated their response. Factor analysis yielded the predicted bipolar factors of valence and arousal: these were obtained in group-aggregated analysis and subsequently confirmed as change dimensions at the intraindividual level. Controversy over the fundamental dimensions of affective space was considered with respect to methodological issues such as factor rotation and sampling of data space. Valence and arousal are discussed as motivational, driving parameters of affective experience and a dynamical systems conceptualization of emotion is proposed.     

The Internet as Cognitive Enhancement

Science and Engineering Ethics - The Internet has been identified in human enhancement scholarship as a powerful cognitive enhancement technology. It offers instant access to almost any type of...     

Cognitive maps as orienting schemata

A "point-to-unseen-targets" task was used to test two theories about the nature of cognitive mapping. The hypothesis that a cognitive map is like a "picture in the head" predicts that (a) the cognitive map should have a preferred orientation and (b) all coded locations should be equally available. These predictions were confirmed in Experiments 1 and 3 when targets were cities in the northeastern United States and learning was from a map. The theory that a cognitive map is an orienting schema predicts that the cognitive map should have no preferred orientation and that targets in front of the body should be localized faster than targets behind the body. These predictions were confirmed in Experiments 1 and 2 when targets were local landmarks that had been learned via direct experience. In Experiment 3, when cities in the Northeast were targets and geographical knowledge had been acquired, in part, by traveling in the Northeast, the observed latency profiles were not as predicted by either theory of cognitive mapping. The results suggest that orienting schemata direct orientation with respect to local environments, but that orientation with respect to large geographical regions is supported by a different type of cognitive structure.     

哲学作为一项认知事业

哲学是一项认知事业,在多重意义上,它与其他各门科学(包括自然科学、社会科学和人文科学)都是连续的:(1)就其研究对象而言,像其他各门科学一样,哲学也是探究我们生活于其中的这个世界,它是人类认知这个世界的总体努力的一部分。(2)就其研究方法而言,哲学与常识和科学之间没有实质性区别。正像科学方法是常识方法的精致化一样,哲学方法也是对常识方法和科学方法的提炼和总结。(3)就其效用而言,哲学和科学都是为了帮助人们更好地生活在这个世界上,过一种体面而有尊严的生活,特别是过一种有价值和有意义的生活。(4)通过哲学史来学习哲学和进入哲学,通过批判地反思先前的哲学理论,开拓新的领域、使用新的方法、提出新的理论来发展哲学,这才是看待哲学与哲学史之间关系的正确态度和做法。(5)关于哲学与科学的如下两个说法只是想当然,似是而非:科学依赖观察和实验,哲学诉诸诠释和理解;科学重点关注实然(事情实际上怎么样),哲学重点关注应然(事情应该怎么样)。     

Cognitive Appraisal as a Predictor of Cognitive Emotion Regulation Choice

More attention has recently been focused on how a person may choose their emotion regulation strategies depending on the situation. The present research examined how people cognitively appraised a situation that they had actually encountered in their life and how this appraisal affected their subsequent cognitive emotion regulation strategies. Three hundred and twenty‐four participants were instructed to recall the most stressful situation in the last month, and to rate how they cognitively appraised the situation (threat, centrality, controllability, commitment, injustice/unfairness, expectedness, expectancy) and how they cognitively regulated their emotion (self‐blame, blaming others, acceptance, refocus on planning, positive refocusing, rumination, positive reappraisal, putting into perspective, catastrophizing). Multiple regression analysis revealed that even after control for other variables, such as age, sex, personality, the time when the situation occurred and the intensity of negative emotion, all criteria of cognitive appraisal except for expectedness predicted cognitive emotion regulation choice. Implications and limitations of this research are discussed.     

Cognitive Effects as Distribution Rescaling

A reanalysis of lexical decision response time distributions from Holden (2002) Holden, J. G. 2002. Fractal characteristics of response time variability. Ecological Psychology, 14: 53–86. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar] reveals a self-similar rescaling of response time distributions in the effect of inconsistency in word's pronunciation-to-spelling relationships. Scaling arises in a wide array of neurophysiological and behavioral systems. A general basis for the emergence of these patterns in biological systems remains under debate. However, biological processes that themselves unfold on timescales ranging from fast to slow often express fractal scaling. One possible basis for self-similar fractal distributions arising for cognitive activity is the fundamental mismatch between relative biological time and absolute clock time.