Assessing the simulation of chaotic systems

Three commercially available software packages—BrainMaker, MicroSaint, and Extend—that simulate the function and operation of neural networks were compared on 11 dimensions. Also, a task-oriented analysis was done on the ability of the programs to use a neural network to output a chaotic array generated by the logistic equation. There were differences in the amount of operator overhead among the programs, but the differences in the simulation performance were not considered to be appreciable.     

WITHIN‐SESSION TRANSITIONS IN CHOICE: A STRUCTURAL AND QUANTITATIVE ANALYSIS

The present study used within‐session transitions between two concurrent schedules to evaluate choice in transition. Eight female Long‐Evans rats were trained to respond under concurrent schedules of reinforcement during experimental sessions that lasted 22 hr. The generalized matching equation was used to model steady‐state behavior at the end of each session, while transitional behavior that emerged following the change in reinforcement schedules was modeled using a logistic equation. The generalized matching and logistic equations were appropriate models for behavior generated during single‐session transitions. A local analysis of behavior on the two response alternatives during acquisition was used to determine the source of preference as revealed in response ratios. The number of “low‐response” visits, those containing three to five responses, remained stable. Preference ratios largely reflected a sharp increase in the number of visits with long response bouts on the rich alternative and a decrease in the number of such visits to the leaner alternative.     

APPROXIMATING CHAOTIC BEHAVIOR

Abstract— Human subjects received feedback showing how closely their responses approximated the chaotic output of the logistic difference function. In Experiment 1, subjects generated analog responses by placing a pointer along a line. In Experiment 2, they generated digital responses in the form of three-digit numbers. In Experiment 3, feedback was sometimes provided and other times withheld. Responses came to approximate three defining characteristics of logistic chaos: Sequences were "noisy," they were extremely sensitive 10 initial conditions, and lag I autocorrelation functions were parabolic in form. Chaos theory may describe some highly variable although precisely determined human behaviors.     

Increasing the variability of response sequences in pigeons by adjusting the frequency of switching between two keys.

Three experiments compared the amounts of behavioral variability generated with two reinforcement rules. In Experiments 1 and 2 pigeons received food whenever they generated a sequence of eight pecks, distributed over two keys, provided that the sequence contained a certain number of change-overs between the keys. Although no variability was required-the birds could obtain all reinforcers by repeating the same sequence-the pigeons emitted a large number of different sequences. In Experiment 3 pigeons received food whenever they generated a sequence that had not occurred during the last 25 trials. After prolonged training, the birds showed more sequence variability than in the first two experiments. The analysis of the internal structure of the response sequences revealed that, in general, (a) the location of the first peck was highly stereotyped; (b) as the trial advanced, the probability of switching to the initially preferred key decreased whereas the probability of switching to the other key increased; and (c) a first-order Markov chain model with transition probabilities given by a logistic function accounted well for the internal structure of the birds' response sequences. These findings suggest that, to a large extent, the variability of response sequences is an indirect effect of adjustments in changeover frequency.     

Behavioral stereotypy and the generalized matching equation

The development of behavioral stereotypy is a common result of exposure to both response-dependent and response-independent reinforcement procedures. The generalized matching equation and two dynamic versions of that equation, which take into account the time differential between reinforcements and their effect on behavior, predict this outcome of many procedures involving reinforcement. Following from the assumption that distinct response topographies, distinct response sequences, or orientations to distinct stimuli can be treated in the equations as distinct classes of behavior, the equations predict that-at least for matching and undermatching-the behavior class that is most biased relative to other behavior classes of the same type will tend to predominate to the exclusion or near exclusion of those behavior classes.     

Similarities of low-dimensional chaotic auditory attractor sequences to quasirandom noise.

The production of sequences of sounds of various pitch levels from the algebra of chaotic attractors' trajectories is relatively straightforward. Meyer-Kress (cited in Kaneko, 1986) suggested that such sequences would be distinguishable from random independent identically distributed sequences. In psychophysical terms, this is a pattern-discrimination or pattern-similarity perception task, but these two tasks are not exactly the same thing. Nine attractors from the algebras of Henon, Zaslavskii (1978), Kaplan and Yorke (1979), Lorenz, and Gregson, and the logistic and Baker transformations, were paired with 10 realizations of a random series. The identification of the random member in each pair, the confidence of identification, and the perceived pairwise similarity were recorded by 65 subjects without initial feedback and by 76 subjects with initial feedback on five trials only, for each of 20 such pairs. The results indicate varying degrees of discriminability; they can be expressed in an analog of the receiver-operating characteristics of the attractors. There is no evidence of any homogeneous basis for the discrimination, and subjects who perform better are apparently not using the same bases as those who perform poorly. The fractal dimensionality of attractors may furnish a basis for their recognition, or the consequent autoregressive spectra induced in finite (short) samples, but recent work suggests the latter spectra can be insensitive to low-dimensional attractor dynamics.     

Informal Drunk Driving Intervention: Psychosocial Correlates Among Young Adult Women and Men1

Based on experimental research on helping and survey findings on drunk driving intervention, we selected 28 variables for study that might relate to informal intervention in a drunk driving situation. We tested six hypotheses by categorizing the 28 variables into personal (12), relationship (4), situational (5), and individual response (7) aspects. Bivariate correlations and multivariate logistic regression analyses were performed between these 28 predictor variables and intervention for 303 college students (192 females and 111 males). Three personal, one relationship, three situational, and four individual responses in situation variables were correlated significantly with intervention. Four significant predictors emerged in the stepwise logistic regression equation: knowing the driver well; having a conversation that encouraged the respondent to intervene; perceiving the driver as needing help; and the respondent's feeling able to intervene. All hypotheses received at least some confirmation in these results, but noteworthy discrepancies from expectations emphasize the need to appreciate differences between studies of helping behavior in the laboratory and this natural form of helping behavior.     

Development of hierarchical structures for actions and motor imagery: a constructivist view from synthetic neuro-robotics study

The current paper shows a neuro-robotics experiment on developmental learning of goal-directed actions. The robot was trained to predict visuo-proprioceptive flow of achieving a set of goal-directed behaviors through iterative tutor training processes. The learning was conducted by employing a dynamic neural network model which is characterized by their multiple time-scale dynamics. The experimental results showed that functional hierarchical structures emerge through stages of developments where behavior primitives are generated in earlier stages and their sequences of achieving goals appear in later stages. It was also observed that motor imagery is generated in earlier stages compared to actual behaviors. Our claim that manipulatable inner representation should emerge through the sensory–motor interactions is corresponded to Piaget’s constructivist view.     

Interpersonal Pattern Dynamics and Adaptive Behavior in Multiagent Neurobiological Systems: Conceptual Model and Data

ABSTRACT

Ecological dynamics characterizes adaptive behavior as an emergent, self-organizing property of interpersonal interactions in complex social systems. The authors conceptualize and investigate constraints on dynamics of decisions and actions in the multiagent system of team sports. They studied coadaptive interpersonal dynamics in rugby union to model potential control parameter and collective variable relations in attacker–defender dyads. A videogrammetry analysis revealed how some agents generated fluctuations by adapting displacement velocity to create phase transitions and destabilize dyadic subsystems near the try line. Agent interpersonal dynamics exhibited characteristics of chaotic attractors and informational constraints of rugby union boxed dyadic systems into a low dimensional attractor. Data suggests that decisions and actions of agents in sports teams may be characterized as emergent, self-organizing properties, governed by laws of dynamical systems at the ecological scale. Further research needs to generalize this conceptual model of adaptive behavior in performance to other multiagent populations.     

Noogenesis—the fundamental problem of our time

The possibility of long wave economic cycles are considered under both market capitalism and command socialism. Capitalist long waves can be generated by a two‐stage multiplier‐accelerator model and socialist long waves can be generated by an equivalent model strictly for investment cycles. Under certain conditions chaotic dynamics can occur at turning points in both cases. It is argued that a systemic crisis leading to a systemic transformation is most likely to occur at such a point.     

Toward an interpretation of dynamic neural activity in terms of chaotic dynamical systems

Using the concepts of chaotic dynamical systems, we present an interpretation of dynamic neural activity found in cortical and subcortical areas. The discovery of chaotic itinerancy in high-dimensional dynamical systems with and without a noise term has motivated a new interpretation of this dynamic neural activity, cast in terms of the high-dimensional transitory dynamics among "exotic" attractors. This interpretation is quite different from the conventional one, cast in terms of simple behavior on low-dimensional attractors. Skarda and Freeman (1987) presented evidence in support of the conclusion that animals cannot memorize odor without chaotic activity of neuron populations. Following their work, we study the role of chaotic dynamics in biological information processing, perception, and memory. We propose a new coding scheme of information in chaos-driven contracting systems we refer to as Cantor coding. Since these systems are found in the hippocampal formation and also in the olfactory system, the proposed coding scheme should be of biological significance. Based on these intensive studies, a hypothesis regarding the formation of episodic memory is given.     

Unemployment and Mental Health: A Longitudinal Perspective

Using longitudinal data, the current study examined the relation between mental health and unemployment. It was assumed that these concepts would mutually influence each other—that is, while the perceived characteristics of the situation of being unemployed affect mental health, mental health may also influence the intention to look for a job, amount and type of job-searching behavior, and the chances of finding a job. Drawing on partly longitudinal data from 229 unemployed Dutch youth, a model relating mental health, perceptions of the unemployment situation, job-searching behaviors, and employment status was tested using structural equation modeling and logistic regression analysis. While the expectations were largely supported, there were also several unexpected results, most notably that participants who felt powerless were more likely to be active job seekers, while only mental health (and not job-seeking behavior) was (weakly) related to the likelihood of finding a job.     

Investigation of drivers’ thresholds of a subjectively accepted driving performance with a focus on automated driving

Lately, the development and implementation of automated driving moved to the center of interest in the automotive industry. In this context, one of the central issues – the configuration of adequate trajectories – is mainly tackled using a technical approach. However, it appears that a technically ideal driving performance does not necessarily coincide with the drivers’ subjective preferences. This study strives to determine thresholds of a subjectively accepted driving performance regarding lateral vehicle control. A second objective is to analyze the influence of selected personal and situational factors on these thresholds. An empirical online survey with 161 participants rating video sequences of driving performances was conducted. The video sequences differed not only with regard to the lateral offset of the ego-vehicle but also concerning the weather (sun/rain) and traffic conditions (existence/driving behavior of oncoming traffic). Additionally, the participants’ driving experience and sensation seeking were considered in the data evaluation. To analyze the data, binary logistic regression analyses were calculated. They revealed that the subjective evaluation of driving performances varies primarily depending on the lateral offset of both the ego-vehicle and the oncoming traffic. The results indicate that regarding the lateral offset certain thresholds of subjectively accepted driving performances do exist. Regarding the development of automated driving systems, two issues need to be considered in order to ultimately guarantee user acceptance. First, the subjective thresholds need to be integrated into the systems’ trajectory planning. Second, the oncoming traffic’s driving behavior has to be considered.     

Sign-tracking with an interfood clock

Food was presented to pigeons, irrespective of their behavior. The fixed 60-s interfood interval was segmented into ten 6-s periods, each signaled by a distinctive stimulus color, ordered by wavelength. This “interfood clock” reliably generated and maintained successively higher rates of key pecking at stimuli successively closer to food. Under extinction, key pecking ceased. When the standard stimulus sequence was changed to a different sequence for each bird, accelerated responding again emerged and was sustained under each of the new color sequences. However, responding was neither maintained nor acquired when each successive interfood interval provided a different random sequence of the ten stimuli. Thus, the interfood clock generated and maintained sign-tracking under stimulus control, and the resulting behavior was attributable neither to stimulus generalization nor to a simple temporal gradient.     

What is chaos and how is it relevant for philosophy of mind?

This paper argues, in agreement with Neuringer, Beggs and others, that if we wish to scientifically characterise human choice, we have to work with a probabilistic or chaos-derived model. This has a number of implications for philosophy of mind. Firstly, it is in theory possible to describe human behaviour with some form of law-like equation; it is just a matter of figuring out what equation best captures the states of our central nervous system. Secondly, it means that our choices are not random but are chaotic: deterministic, but just hard to predict due to internal complexity. According to the current research, our actions are most likely caused by ‘precipitated avalanches’ of neural activity, which are difficult to predict due to chaos.     

Alternative Lens Model Equations for Dichotomous Judgments about Dichotomous Criteria

The Brunswik lens model typically represents a judge's accuracy using parameters derived from linear regression. This is not optimal if the judgment or the ecological criterion is dichotomous. Alternative approaches, modeling dichotomies using logistic regression, or linearizing judgments with confidence ratings, have not been compared with the same data. Four techniques for deriving lens model equation parameters were compared: (i) linear and (ii) logistic regression applied to dichotomous patient outcomes and judgments; (iii) linear regression with confidence‐adjusted judgments but dichotomous patient outcomes; and (iv) a hybrid with a linear model of the confidence‐adjusted judgments and a logistic model of the patient outcomes. Judgment accuracy (r_a) was slightly higher with confidence adjustment of the categorical judgments. The logistic lens model accounted for a higher proportion of r_a than the linear lens model; the confident‐linear and hybrid lens models were intermediate. For up to a quarter of participants, different methods identified different cues as most important. Display condition differences in achievement r_a and in lens model components are similar with all lens model methods. Each of the three alternative lens model equation methods improves on the linear lens model equation's decomposition of the accuracy of dichotomous judgments. Confidence adjustment improves achievement although it requires additional work from the subjects. The logistic lens model equation explains the highest proportion of achievement, but with a small stimulus set, it is more vulnerable to cue intercorrelations than either the linear or the confident linear lens model equation. Copyright © 2016 John Wiley & Sons, Ltd.     

Empirical Support for an Evolutionary Model of Self‐Destructive Motivation

We tested predictions generated from an evolutionary account of self‐destructive motivation in two survey studies of 18–24‐year‐old university students. As hypothesized, hierarchical regressions showed that the positive relationship between perceived burden to family and suicide ideation was amplified for participants with low measured health and romantic relationship satisfaction, and for participants with relatively young mothers. The moderating effect of maternal age was also observed in logistic regressions of suicide attempts. These effects occurred independently of depression, hopelessness, and other relevant extraneous variables. Results have implications for understanding self‐destructive motivation, assessing suicide risk, and preventing suicidal thinking and behavior.     

Should metacognition be measured by logistic regression?

Are logistic regression slopes suitable to quantify metacognitive sensitivity, i.e. the efficiency with which subjective reports differentiate between correct and incorrect task responses? We analytically show that logistic regression slopes are independent from rating criteria in one specific model of metacognition, which assumes (i) that rating decisions are based on sensory evidence generated independently of the sensory evidence used for primary task responses and (ii) that the distributions of evidence are logistic. Given a hierarchical model of metacognition, logistic regression slopes depend on rating criteria. According to all considered models, regression slopes depend on the primary task criterion. A reanalysis of previous data revealed that massive numbers of trials are required to distinguish between hierarchical and independent models with tolerable accuracy. It is argued that researchers who wish to use logistic regression as measure of metacognitive sensitivity need to control the primary task criterion and rating criteria.     

Information‐Theoretic Measures Predict the Human Judgment of Rhythm Complexity

To formalize the human judgment of rhythm complexity, we used five measures from information theory and algorithmic complexity to measure the complexity of 48 artificially generated rhythmic sequences. We compared these measurements to human prediction accuracy and easiness judgments obtained from a listening experiment, in which 32 participants guessed the last beat of each sequence. We also investigated the modulating effects of musical expertise and general pattern identification ability. Entropy rate and Kolmogorov complexity were correlated with prediction accuracy, and highly correlated with easiness judgments. A logistic regression showed main effects of musical training, entropy rate, and Kolmogorov complexity, and an interaction between musical training and both entropy rate and Kolmogorov complexity. These results indicate that information‐theoretic concepts capture some salient features of the human judgment of rhythm complexity, and they confirm the influence of musical expertise on complexity judgments.     

Choice in transition: Replication and extension to preschool children in a naturalistic setting

This study replicated previous basic research into the dynamics of choice and extended this analysis to children's behavior in a naturalistic setting. Two preschoolers with disabilities were observed interacting with their teachers at baseline and during an experimental analysis involving four pairs of concurrent variable‐interval schedules of adult attention implemented by an experimenter. Each child was exposed to four experimental phases in which the relative reinforcer rates for on‐ and off‐task behavior were 10:1, 1:1, 1:10, and reversed back to 10:1. The 10:1 phase was designed to mimic the same schedules and types of adult attention observed at baseline. We used the generalized matching equation to model steady‐state behavior at the end of the transition phases and to evaluate changes in sensitivity at various points throughout the phases. Choice in transition was evaluated by plotting log behavior ratios by session, cumulated time on‐ and off‐task and cumulated attention for on‐ and off‐task behavior by session, and interreinforcer behavior ratios following different sequences of the first four reinforcer deliveries. The generalized matching equation accounted for a large proportion of variance in steady‐state responding, sensitivity values increased steadily throughout the phases, patterns of choice in transition were similar to those reported in basic research, and interreinforcer preference generally shifted toward the just‐reinforced alternative. These findings are consistent with previous basic research and support the generality of the dynamics of choice to children's on‐ and off‐task behavior reinforced by adult attention.