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1.
The role of probability forecasting in the purposive behavior under conditions of subjective uncertainty is considered in terms of the theory of functional systems. Participation of the probability forecasting in the afferent synthesis, goal formation, formation of the acceptor of action result and action program, and, finally, in the action program actualization is substantiated. The model of behavior under conditions of subjective uncertainty is advanced. It includes all the classical elements of the model of behavioral act developed by P.K. Anokhin. In order to take into account the probability aspects of behavior, the role of probability forecasting is emphasized at every stage of the system functioning. In addition to the classical elements, two novel components are introduced. These are the "memory buffer" (results of searching reactions) and the apparatus of probability decisions about changes in the action program. By the memory buffer an apparatus is meant, which gathers and stores the information about the results of many behavioral acts performed during the actualization of the action program. This information is used in the process of making a probability decision as whether to alter or not the action program after each specific behavioral act. Such an approach integrates the probability forecasting and the theory of functional systems. The theory becomes universal, i.e., applicable not only to deterministic but also to probabilistic environments. 相似文献
2.
Sudakov KV 《Uspekhi fiziologicheskikh nauk》2000,31(1):81-96
On the basis of the theory of functional systems, suggested by P. K. Anokhin, leading principals of system organization of human functions are regarded. General characteristics of functional systems are stated. Some peculiarities of intrasystem and intersystem organization of functional systems of human organism are discovered. The role of functional systems in organization of normal human live activity as well as under psychoemotional stress and pathology is shown. System principals of compensation of disordered functions during rehabilitation of persons undergone stresses and ecologically unfavorable loads are considered. 相似文献
3.
4.
A method is presented which renders parameter estimation possible in systems of non-linear differential equations where normally no solution exists in terms of analytic functions and which have to be solved numerically. The method uses the concept of sensitivity equations. Two examples are given, taking mathematical models for membrane action potentials in nerve and heart muscle by Hodgkin and Huxley and by Beeler and Reuter. The model equations together with the corresponding system of sensitivity equations are given, which are necessary to estimate maximum conductivity coefficients defining the interactions of different ionic current components. A computer program is described and results of action potential numerical analysis are presented using simulated data. It can be seen, that even with superimposed simulated noise the real parameter values are estimated in an excellent manner. The method can be used to interpret observed changes in action potential time courses under physiological and pharmacological conditions. 相似文献
5.
Shimansky YP 《Biological cybernetics》2011,104(4-5):225-233
It is well known from numerous studies that perception can be significantly affected by intended action in many everyday situations, indicating that perception and related decision-making is not a simple, one-way sequence, but a complex iterative cognitive process. However, the underlying functional mechanisms are yet unclear. Based on an optimality approach, a quantitative computational model of one such mechanism has been developed in this study. It is assumed in the model that significant uncertainty about task-related parameters of the environment results in parameter estimation errors and an optimal control system should minimize the cost of such errors in terms of the optimality criterion. It is demonstrated that, if the cost of a parameter estimation error is significantly asymmetrical with respect to error direction, the tendency to minimize error cost creates a systematic deviation of the optimal parameter estimate from its maximum likelihood value. Consequently, optimization of parameter estimate and optimization of control action cannot be performed separately from each other under parameter uncertainty combined with asymmetry of estimation error cost, thus making the certainty equivalence principle non-applicable under those conditions. A hypothesis that not only the action, but also perception itself is biased by the above deviation of parameter estimate is supported by ample experimental evidence. The results provide important insights into the cognitive mechanisms of interaction between sensory perception and planning an action under realistic conditions. Implications for understanding related functional mechanisms of optimal control in the CNS are discussed. 相似文献
6.
K. V. Sudakov 《Biology Bulletin》2012,39(1):51-59
The theoretical concept concerning informational aspects of systemic cerebration was proved based on the theory of functional
systems formulated by P.K. Anokhin. It has been postulated that informational models of discrete informational systemoquantum
in the form of holographic images of mentality were constructed. They are constructed for the dynamics of formation of functional
systems of cerebral architectonics, which determine behavior and mentality on morphofunctional structures of acceptors of
the outcome of action. The leading role of the dominant motivations in building and rapid retrieval of informational systemoquamtums
of mentality from the memory was underlined. The role of emotions in subjective informational estimation of system cerebration
was analyzed. It has been suggested that the parameters of achievements of subjects’ adaptive results by means of reverse
sensory input are left on the action outcome acceptor structures in the form of specific informational holographic images. 相似文献
7.
Daniel D. Wiegmann Kelly L. Weinersmith Steven M. Seubert 《Journal of mathematical biology》2010,60(4):543-572
The behavior of females in search of a mate determines the likelihood that high quality males are encountered and adaptive
search strategies rely on the effective use of available information on the quality of prospective mates. The sequential search strategy was formulated, like most models of search behavior, on the assumption that females obtain perfect information on the quality
of encountered males. In this paper, we modify the strategy to allow for uncertainty of male quality and we determine how
the magnitude of this uncertainty and the ability of females to inspect multiple male attributes to reduce uncertainty influence
mate choice decisions. In general, searchers are sensitive to search costs and higher costs lower acceptance criteria under
all versions of the model. The choosiness of searchers increases with the variability of the quality of prospective mates
under conditions of the original model, but under conditions of uncertainty the choosiness of searchers may increase or decrease with the variability of inspected male attributes. The behavioral response depends on the functional relationship between
observed male attributes and the fitness return to searchers and on costs associated with the search process. Higher uncertainty
often induces searchers to pay more for information and under conditions of uncertainty the fitness return to searchers is
never higher than under conditions of the original model. Further studies of the performance of alternative search strategies
under conditions of uncertainty may consequently be necessary to identify search strategies likely to be used under natural
conditions. 相似文献
8.
We monitored chimpanzee welfare during the introduction of on-exhibit cognitive research training and testing, as measured by behavior and interest in such training, and related individual variation to personality assessments. We observed 11 chimpanzees (six males; five females) over a 16-month period and compared their behavior across three conditions: (1) Baseline (nontraining/research situations) and (2) an on-going, off-exhibit program of Husbandry Training and (3) Research Pod Activities, on-exhibit, group training for cognitive testing. There was considerable individual variation in their interest levels during research sessions; females and those scoring higher for Openness were present more frequently (including those who actively participated and those who observed others participating), but interest did not vary in relation to rates of self-directed behaviors (SDBs), rank, or the level of social disruptions within the group (i.e. large-scale displays or fights). The frequency of SDBs was predicted by the Neuroticism personality factor, but did not differ across baseline and training contexts, indicating that these activities do not negatively impact welfare. We also explored vigilance as an indicator of social uncertainty, but social monitoring did not differ in relation to either social context or rank. Finally, we explored how the specific characteristics of the research context impacted on SDBs; namely, social context, reward contingency, and visual access to keepers. SDBs increased only when visual access to keepers was restricted, suggesting that visual contact reduced uncertainty in novel training contexts. Overall, the introduction of a cognitive research program did not compromise welfare, and the chimpanzees' repeated interest and willingness to participate suggests that the research was enriching. 相似文献
9.
The spontaneous and light-evoked firing patterns of the compound action potentials (CAPs) in the isolated eye of Aplysia are experimentally observed from a control systems viewpoint. The eye, exhibiting an endogenous bursting activity and a marked circadian rhythm in darkness, is a self-excited system and responds to illumination with a controlled electrical activity. It is represented by the nonlinear systems model predicting the firing-rate variation of the CAPs. Construction of the model is based on the eye's biological model reported in the literature, and involves an experimental analysis of the system characteristics using linear approximation and conventional control systems techniques. The model is simulated and found to adequately conform to the observed behavior of the eye under various experimental conditions. 相似文献
10.
Sudakov KV 《Uspekhi fiziologicheskikh nauk》2001,32(3):79-86
New trends in the development of the theory of functional systems proposed by P.K. Anokhin in the scientific complex P.K. Anokhin Institute--Department of Normal Physiology during the last twenty five years are regarded. It has been shown that the functional systems represent an objective reality. Holographic and informational properties of the functional systems and general principles of their interrelations in the whole organism i.e. hierarchic domination, multiparametric and successive interaction have been disclosed. Some notions about "systemo-quanta" of vital activity as discrete units of dynamic activity of functional systems have been formulated. Further developments in the systemogenesis of behavioral acts also are presented. New ideas about pacemaker mechanism of dominant biological motivations, the role of oligopeptides in the system organization of behavioral acts have been formulated. The role of early genes in formation of behavioral reactions of animals and in the mechanisms of emotional stress is shown. The role of some oligopeptides in the mechanisms of resistance to emotional stress is stated. Some devices modeling the properties of functional systems and able to assess different organism's functional systems have been developed. Practical application of the theory of functional systems is also shown in the paper. 相似文献
11.
AM Jefcoat 《Lab animal》2012,41(9):260-263
In an animal care and use program in a research setting, events that have a negative impact on animal well-being do not typically occur spontaneously and arbitrarily. It takes the convergence of multiple missteps, miscalculations and misinterpretations of conditions for a serious accident to take place. Two concepts drawn from wilderness survival training can be applied to any research animal care and use program to reduce adverse events. The first, derived from the accident matrix model, is the concept of 'problem vectors,' or conditions, behaviors and policies that increase the likelihood of an adverse event. Identifying problem vectors and diverting them before they intersect to create an adverse event can considerably improve animal well-being and reduce the number of protocol violations and reportable events. The second concept is that of doing the 'next right thing' when an adverse event does occur in an animal program. The next right thing is a response characterized by unified directed action toward fixing problems without engaging in behaviors that might worsen the situation. Adopting an institution-wide approach of diverting problem vectors and pursuing the next right thing can result in better prevention and management of adverse events. 相似文献
12.
代谢组学是功能基因组学和系统生物学研究不可或缺的重要组成部分,是通过考察生物体系受刺激或扰动前后代谢产物的动态变化,研究生物体系的代谢网络的一种技术。应用代谢组学高通量、整体性的研究思路来理解中药的作用过程,与中医药的整体、辩证观点是一致的。代谢组学已成为中药研发的一个重要途径和手段,为中药现代化在技术上提供巨大支持,有助于为中药现代化研究寻找更多有效的突破口。本文在前人综述的基础上,着重概括了中药代谢组学研究方法近3年来在中药有效物质基础和作用机制、药物作用模型的鉴别和确证、毒性研究和中药安全性评价等方面的应用情况,同时展望了代谢组学方法所面临的机遇和挑战。 相似文献
13.
Sequences of behavior are highly predictable (stereotyped) during some segments and less predictable during transitions between those segments. Statistical characterization of behavior must involve observation of the behavior under different stimulus conditions, which includes how stimuli associated with behavioral releasers come to trigger behavior during learning. For example, the feeding motor program (FMP) of the honey bee Apis mellifera (Hymenoptera: Apidae) during proboscis extension can be divided into three response phases (Rehder 1987). We conditioned honey bees in an olfactory conditioning paradigm with one or several rewarded trials during which an odorant was paired with the sugar-water unconditioned stimulus (US); the latter elicits proboscis extension and feeding in properly motivated bees. By recording electromyogram activity from one of the muscles that move the proboscis during feeding, we quantified the bees' responses during an unrewarded test with either the conditioned odorant, a different (novel) odorant, or the sugar-water US. Various parameters of the response phases of the FMP varied in a consistent manner across these experimental treatments, with certain stimuli eliciting stronger, more consistent responses. The different response phases followed one another in time with some variability and statistical uncertainty. For example, the length of an individual licking movement with the glossa was relatively invariant, and may indicate that this parameter can be used to differentiate the FMP into more basic, independent units. Our work shows how learned information may release action patterns in ways slightly different from traditional sign-stimuli releasers. 相似文献
14.
We have studied the kinetics of the conservative behavior of systems which are subject to the dual action of an external effector or a negative feedback. Conditions have been found under which the dual-action mechanism produces conservative behavior. Negative feedback alone was shown not to produce the conservative behavior of an enzyme-receptor system. 相似文献
15.
Seth J. Wenger Nicholas A. Som Daniel C. Dauwalter Daniel J. Isaak Helen M. Neville Charles H. Luce Jason B. Dunham Michael K. Young Kurt D. Fausch Bruce E. Rieman 《Global Change Biology》2013,19(11):3343-3354
Forecasts of species distributions under future climates are inherently uncertain, but there have been few attempts to describe this uncertainty comprehensively in a probabilistic manner. We developed a Monte Carlo approach that accounts for uncertainty within generalized linear regression models (parameter uncertainty and residual error), uncertainty among competing models (model uncertainty), and uncertainty in future climate conditions (climate uncertainty) to produce site‐specific frequency distributions of occurrence probabilities across a species' range. We illustrated the method by forecasting suitable habitat for bull trout (Salvelinus confluentus) in the Interior Columbia River Basin, USA, under recent and projected 2040s and 2080s climate conditions. The 95% interval of total suitable habitat under recent conditions was estimated at 30.1–42.5 thousand km; this was predicted to decline to 0.5–7.9 thousand km by the 2080s. Projections for the 2080s showed that the great majority of stream segments would be unsuitable with high certainty, regardless of the climate data set or bull trout model employed. The largest contributor to uncertainty in total suitable habitat was climate uncertainty, followed by parameter uncertainty and model uncertainty. Our approach makes it possible to calculate a full distribution of possible outcomes for a species, and permits ready graphical display of uncertainty for individual locations and of total habitat. 相似文献
16.
This paper presents a model describing how the uncertainty due to influential exogenous processes combines with stochasticity intrinsic to physiological aging processes and propagates through time to generate uncertainty about the future physiological state of the population. Variance expressions are derived for (a) the future values of the physiological variables under the assumption that external factors evolve under a linear stochastic diffusion process, and (b) the cohort survival functions and cohort life expectancies which reflect the uncertainty in the future values of the physiological variables. The model implies that a major component of uncertainty in forecasts of the physiological characteristics of a closed cohort is due to differential rates of survival associated with different realizations of the external process. This suggests that the limits to forecasting may be different in physiological systems subject to systematic mortality than in physical systems such as weather where the concepts of closed cohorts and of mortality selection have no simple analog. 相似文献
17.
Gerhard Roth 《当今生物学》2016,46(3):177-183
Guilt and responsibility In criminal law, the notion of guilt is based on the metaphysical principle of free will implying the ability to “do otherwise” under identical physico‐psychical conditions. This stands in contradition to scientific thinking as well as psychological and neurobiological insight into the development of personality and motive structures. It is proposed to replace the notion of free will by that of formation of will in private law. This implies the ability to adequately deliberate the conditions and possible consequences of one's own actions. This ability is understood as the result of normal development of the brain and its cognitive, emotional and executive functions. From this derives the responsibility of a person for his or her actions. 相似文献
18.
Wildes D Anderson LM Sabogal A Marqusee S 《Protein science : a publication of the Protein Society》2006,15(7):1769-1779
We have defined the free-energy profile of the Src SH2 domain using a variety of biophysical techniques. Equilibrium and kinetic experiments monitored by tryptophan fluorescence show that Src SH2 is quite stable and folds rapidly by a two-state mechanism, without populating any intermediates. Native state hydrogen-deuterium exchange confirms this two-state behavior; we detect no cooperative partially unfolded forms in equilibrium with the native conformation under any conditions. Interestingly, the apparent stability of the protein from hydrogen exchange is 2 kcal/mol greater than the stability determined by both equilibrium and kinetic studies followed by fluorescence. Native-state proteolysis demonstrates that this "super protection" does not result from a deviation from the linear extrapolation model used to fit the fluorescence data. Instead, it likely arises from a notable compaction in the unfolded state under native conditions, resulting in an ensemble of conformations with substantial solvent exposure of side chains and flexible regions sensitive to proteolysis, but backbone amides that exchange with solvent approximately 30-fold slower than would be expected for a random coil. The apparently simple behavior of Src SH2 in traditional unfolding studies masks the significant complexity present in the denatured-state ensemble. 相似文献
19.
A generic mechanism - networked buffering - is proposed for the generation of robust traits in complex systems. It requires two basic conditions to be satisfied: 1) agents are versatile enough to perform more than one single functional role within a system and 2) agents are degenerate, i.e. there exists partial overlap in the functional capabilities of agents. Given these prerequisites, degenerate systems can readily produce a distributed systemic response to local perturbations. Reciprocally, excess resources related to a single function can indirectly support multiple unrelated functions within a degenerate system. In models of genome:proteome mappings for which localized decision-making and modularity of genetic functions are assumed, we verify that such distributed compensatory effects cause enhanced robustness of system traits. The conditions needed for networked buffering to occur are neither demanding nor rare, supporting the conjecture that degeneracy may fundamentally underpin distributed robustness within several biotic and abiotic systems. For instance, networked buffering offers new insights into systems engineering and planning activities that occur under high uncertainty. It may also help explain recent developments in understanding the origins of resilience within complex ecosystems. 相似文献
20.
M. K. Zhemchuzhnikov A. N. Knyazev 《Journal of Evolutionary Biochemistry and Physiology》2011,47(6):571-577
The character of motor activity of female crickets Gryllus argentinus Sauss. executing reproductive and defense behavior was studied under normal conditions and under conditions of inactivation
of the cercal organ at different stages of imaginal ontogeny (on day 2, 7 and 12). Various forms of motor reactions of females
placed on a movable spherical support to models of intraspecies calling and aggressive male signals were described and analyzed.
Reversible inactivation of cercal receptors was shown to result in disturbance of the mechanisms of realization of normal
reproductive behavior at the end of pre-reproductive and in the beginning of reproductive periods of imaginal ontogeny. It
is manifested as statistically significant reduction of the proportion of positive phonotactic reactions in response to a
model of the male calling song in animals with experimental sensory pathology as compared to control groups of crickets (the
norm). No significant differences in proportions of typical directional motor reactions to presentation of the aggressive
signal under normal conditions and under conditions of sensory pathology were found. Thus preservation of the tympanic organ
was demonstrated to be a necessary but not sufficient condition for realization of adequate acoustic reproductive behavior.
Only working together, distant mechanoreceptor systems (the cercal and tympanic ones) are able to provide adequacy of behavior.
This conclusion confirmed the proposed earlier hypothesis about interaction of distant mechanoreceptor systems and about existence
of an integrated sensory complex necessary for realization of adequate behavior of insects. 相似文献