The emergence of personality: Dynamic foundations of individual variation

We conceptualize personality and individual variation from the perspective of dynamical systems. People’s thoughts, feelings, and predispositions for action are inherently dynamic, displaying constant change due to internal mechanisms and external forces, but over time the flow of thought and action converges on a narrow range of states—a fixed-point attractor—that provides cognitive, affective, and behavioral stability. An attractor for personal dynamics develops through two mechanisms: the synchronization of individuals’ internal states in social interaction, and the self-organization of thoughts and feelings with respect to a higher-order property (e.g., goal, self-concept). We present formal models of both processes and instantiate each in computer simulations. Discussion centers on the implications of interpersonal synchronization and self-organization dynamics for issues in personality psychology, including shared vs. non-shared environmental influences on personality development, the expression of personality in social interaction, personal stability vs. change, personal vs. situational causation, and the emergence of self-concept.     

Developmental emergence of self-referential and inhibition mechanisms of body movements underling felicitous behaviors

In young infants, activation or inhibition of body movements on perception of environmental events is important to enable them to act on the world or understand the world. To reveal the development of this ability, we observed movement patterns in all four limbs under the two experimental conditions. Infants assigned to the interaction condition were provided a connection between their arm and a toy, which allowed movements of the critical arm to produce movements in the overhead mobile. Infants assigned to the stimulation condition were presented with similar movements of the toy emulated by the experimenter. In 3-month-old infants, the arm movements increased under the interaction condition, whereas they decreased under the stimulation condition. Such condition-dependent behavior dissociation was not observed in 2-month-old infants. These results suggest that the distinct behavior of an "observer" of environmental events was differentiated from that of a "player" interacting with the surroundings between 2 and 3 months of age. The emergence of differentiation of behaviors points toward the development of self-referential and inhibition mechanisms in the perceptual-motor and attention/evaluation system in the cortico-subcortical network.     

A model to investigate the mechanisms underlying the emergence and development of independent sitting

When infants first begin to sit independently, they are highly unstable and unable to maintain upright sitting posture for more than a few seconds. Over the course of 3 months, the sitting ability of infants drastically improves. To investigate the mechanisms controlling the development of sitting posture, a single‐degree‐of‐freedom inverted pendulum model was developed. Passive muscle properties were modeled with a stiffness and damping term, while active neurological control was modeled with a time‐delayed proportional‐integral‐derivative (PID) controller. The findings of the simulations suggest that infants primarily utilize passive muscle stiffness to remain upright when they first begin to sit. This passive control mechanism allows the infant to remain upright so that active feedback control mechanisms can develop. The emergence of active control mechanisms allows infants to integrate sensory information into their movements so that they can exhibit more adaptive sitting.     

Dynamic systems as tools for analysing human judgement

With the advent of computers in the experimental labs, dynamic systems have become a new tool for research on problem solving and decision making. A short review of this research is given and the main features of these systems (connectivity and dynamics) are illustrated. To allow systematic approaches to the influential variables in this area, two formal frameworks (linear structural equations and finite state automata) are presented. Besides the formal background, the article sets out how the task demands of system identification and system control can be realised in these environments, and how psychometrically acceptable dependent variables can be derived.     

Accountability as a deterrent to self-enhancement: the search for mechanisms

Although self-enhancement is linked to psychological benefits, it is also associated with personal and interpersonal liabilities (e.g., excessive risk taking, social exclusion). Hence, structuring social situations that prompt people to keep their self-enhancing beliefs in check can confer personal and interpersonal advantages. The authors examined whether accountability can serve this purpose. Accountability was defined as the expectation to explain, justify, and defend one's self-evaluations (grades on an essay) to another person ("audience"). Experiment 1 showed that accountability curtails self-enhancement. Experiment 2 ruled out audience concreteness and status as explanations for this effect. Experiment 3 demonstrated that accountability-induced self-enhancement reduction is due to identifiability. Experiment 4 documented that identifiability decreases self-enhancement because of evaluation expectancy and an accompanying focus on one's weaknesses.     

Dynamic aspects of stimulus-response correspondence: evidence for two mechanisms involved in the Simon effect

It has been recently proposed that the time course of the Simon effect may vary across tasks, which might reflect different types of stimulus-response (S-R) transmissions (E. Wascher, U. Schatz, T. Kuder, & R. Verleger, 2001). The authors tested this notion in 4 experiments by comparing Simon effects evoked by horizontal and vertical S-R arrangements. The temporal properties of the effect, as well as lateralized readiness potential-difference waves, indicated a fast and transient influence of the horizontal, but a slow and sustained influence of the vertical spatial stimulus feature on performance. Additional evidence for this temporal dissociation was obtained in experiments that induced a shortening or lengthening of the mean response time. Thus, the data strongly indicate that there are 2 temporally dissociable mechanisms involved in generating the Simon effect for horizontal and vertical S-R relations.     

Two-bubble instabilities in quasi-two-dimensional foams

We study the effect of the experimental set-up on the structure and rheology of two-dimensional foams. We perform the same experiment, in which a sequence of topological instabilities is realized, in three different set-ups, allowing the relative merits of each system to be discussed. The experiment consists of an in-plane deformation of two bubbles which are confined laterally by bars and wholly or partially confined above and below by glass plates and liquid surfaces. An instability of the bubbles occurs when the bar spacing is increased or decreased (traction or compression) beyond a critical value. The critical values depend strongly on the experimental set-up used, and, because of the finite liquid fraction of the system, do not always agree with predictions based upon a two-dimensional analysis of a dry foam. This behaviour gives information about the discrepancies between reported experimental results on macroscopic two-dimensional foams under shear.     

The natural emergence of reasoning about the afterlife as a developmental regularity

Participants were interviewed about the biological and psychological functioning of a dead agent. In Experiment 1, even 4- to 6-year-olds stated that biological processes ceased at death, although this trend was more apparent among 6- to 8-year-olds. In Experiment 2, 4- to 12-year-olds were asked about psychological functioning. The youngest children were equally likely to state that both cognitive and psychobiological states continued at death, whereas the oldest children were more likely to state that cognitive states continued. In Experiment 3, children and adults were asked about an array of psychological states. With the exception of preschoolers, who did not differentiate most of the psychological states, older children and adults were likely to attribute epistemic, emotional, and desire states to dead agents. These findings suggest that developmental mechanisms underlie intuitive accounts of dead agents' minds.     

Beyond androgyny: The emergence of sex-role transcendence as a theoretical construct

Recent trends in sex-role research are reviewed with the purpose of showing a paradigm shift in the kinds of issues and questions thought to be important for an understanding of sex-role development. Two recent advances, conceptualizations of androgyny and sex-role transcendence are described with particular emphasis on the emergence of sex-role transcendence as a new theoretical construct. It is argued that while personality, social-learning, and structural-developmental theories account for sex-role identity and androgyny, only structural-developmental theory provides an adequate conceptual framework for the construct of sex-role transcendence. Questions are raised concerning the empirical demonstration of the concept.     

A bifurcation theory for the instabilities of optimization and design

The world I grew up in believed that change and development in life are part of a continuous process of cause and effect, minutely and patiently sustained throughout the millenniums. With the exception of the initial act of creation ..., the evolution of life on earth was considered to be a slow, steady and ultimately demonstrable process. No sooner did I begin to read history, however, than I began to have my doubts. Human society and living beings, it seemed to me, ought to be excluded from so calm and rational a view. The whole of human development, far from having been a product of steady evolution, seemed subject to only partially explicable and almost invariably violent mutations. Entire cultures and groups of individuals appeared imprisoned for centuries in a static shape which they endured with long-suffering indifference, and then suddenly, for no demonstrable cause, became susceptible to drastic changes and wild surges of development. It was as if the movement of life throughout the ages was not a Darwinian caterpillar but a startled kangaroo, going out towards the future in a series of unpredictable hops, stops, skips and bounds. Indeed, when I came to study physics I had a feeling that the modern concept of energy could perhaps throw more light on the process than any of the more conventional approaches to the subject. It seemed that species, society and individuals behaved more like thunder-clouds than scrubbed, neatly clothed and well-behaved children of reason. Throughout the ages life appeared to build up great invisible charges, like clouds and earth of electricity, until suddenly in a sultry hour the spirit moved, the wind rose, a drop of rain fell acid in the dust, fire flared in the nerve, and drums rolled to produce what we call thunder and lightening in the heavens and chance and change in human society and personality.LAURENS VAN DER POST, The Lost World of the Kalahari     

Time-Limited Dynamic Psychotherapy as a Model for Short-Term Inpatient Groups

The present article proposes a method, practiced by the author, to adapt time-limited dynamic psychotherapy (TLDP), a short-term individual psychodynamic therapy, for use with inpatient psychotherapy groups. Characteristics of TLDP which suggest the usefulness of such an adaptation, including short-term duration, specific treatment focus, rapid conceptualizations and broad selection of patients, and emphasis on the here-and-now in therapy, are discussed. The general approach to treatment, a supportive stance that involves an identification of maladaptive interpersonal issues, and then working on these issues without directly confronting the patients, is described. Specific therapeutic techniques for common inpatient group situations are also discussed.     

Preschoolers' understanding of germs as invisible mechanisms

Recent studies have presented conflicting claims regarding whether young children's reasoning about biological content involves a unique set of causal mechanisms and theoretical entities. Three studies examined preschoolers' understanding of nonobservable causal mechanisms in causes of illness. According to traditional accounts, these children know that certain behaviors lead to illness but have no idea why or how. Many of the behaviors children cite as causes are actually mediated by the action of germs (e.g., contamination and contagion). Do children recognize that germs (nonobvious, invisible particles) are the mechanisms involved in some cases of illness causation? Study 1 demonstrates that 4- and 5-year-olds' predictions of who will get sick in cases of contamination and contagion are based on the presence or absence of germs. Study 2 serves as a control and further tests how children generalize this mechanism: Which causes do children think are mediated by germs? Data suggest that preschoolers understand but undergeneralize the role of germs. A final study indicates that younger preschoolers (3-year-olds) recognize that appearances may be deceiving when it comes to judging causes of illness. This understanding would seem to be a precursor to beliefs about specific mechanisms. Results are discussed in terms of commonsense theories and early conceptions of biology.     

Social roles as mechanisms for psychological need satisfaction within social groups.

The authors explored ways in which needs for autonomy and relatedness can be simultaneously met within the context of group life. Specifically, it was hypothesized that social role performances provide means of both expressing the self and connecting with group members. Consistent with the assumption that autonomy and relatedness are complementary rather than conflictual, these needs were positively correlated in all 5 studies. Consistent with the authors' assumption that these needs are both important, feelings of autonomy and relatedness in social roles independently predicted subjective well-being, as measured by concurrent (Studies I and 3), peer-report (Study 2). and longitudinal (Studies 4 and 5) methodologies. Study 5 showed that participants whose characteristics matched an assigned role experienced more autonomy and relatedness and thus more positive mood during a group task. Implications for optimal functioning in group contexts are discussed.     

Temporalizing ontology: a case for pragmatic emergence

Synthese - Despite an attempt to break with the hierarchical picture in traditional emergentist thought, non-standard accounts of emergence are often still committed to a premise that ontology is...     

Shoemaker on emergence

Sydney Shoemaker has recently given an account of emergent properties according to which emergent properties are a special type of structural property and the determination relation holding between emergent properties and their base properties is one of “mere nomological supervenience.” According to Shoemaker, emergent properties are what he calls type-2 microstructural properties, whereas physical properties are type-1 microstructural properties. After highlighting the advantages of viewing emergent properties as a special class of microstructural properties, I show how according to his own causal theory of properties type-2 microstructural properties actually reduce to type-1 microstructural properties, and thus do not truly count as emergent. I then suggest an alternative view according to which emergent properties are actually a third type of microstructural property, one not considered by Shoemaker. I conclude with reflections why we might view the dependence relation between emergent properties and their physical base properties as a causal relation rather than one of mere supervenience.     

Default Logic as Dynamic Doxastic Logic

Dynamic doxastic logic (DDL) is used in connexion with theories of belief revision. Here we try to show that languages of DDL are suitable also for discussing aspects of default logic. One ingredient of our analysis is a concept of coherence-as-ratifiability.     

Iontophoretically applied potassium ions as an experimental pain stimulus for investigating pain mechanisms

The present study investigated the psychophysical characteristics of potassium iontophoresis and its suitability as an experimental pain stimulus. Experiment 1 investigated the optimal duration of the pain stimulus for reliable reporting across repeated trials and whether the relationship between stimulus and subject response was linear, logarithmic, or a power function. In Experiment 2, the optimal interstimulus interval (ISI) was determined for reliable pain reporting, and stimulus history effects, both in terms of session effects and the effects of immediately preceding stimuli, were evaluated. In Experiment 3, potassium iontophoresis was compared with a sodium iontophoresis control. Linear functions described the stimulus-pain relationship best. No significant differences in the goodness-of-fit coefficients of determination, correlations, or coefficients of variation were found for the stimulus durations of 1, 2, and 4 sec. Significant stimulus history effects were found across a session, with adaptation and enhancement of responding for low- and moderate-intensity stimuli, respectively. The effects of the immediately preceding stimuli were suppression or enhancement of pain response, depending on the ISI, the preceding stimulus intensity, and the present stimulus intensity. Potassium iontophoresis was a significantly more effective pain stimulus than was sodium iontophoresis. It was concluded that potassium iontophoresis is a convenient and reliable experimental pain stimulus, which can be presented rapidly and repeatedly with minimal loss in consistency of subject pain report. Potassium iontophoresis provides a tool for investigating the neural modulation of pain in the relative absence of inflammation processes and tissue damage.     

The emergence of representation in search: Understanding the hider as an independent agent

Corrigan's results point the way toward a reconceptualization of how the development of representation affects search. The child does not cognitively recreate the invisible displacements of the object. Instead she seems to understand that the hider is an independent agent who can use simple hiding strategies that the child does not directly perceive. This representational skill for search, we propose, is one realization of a general representational capacity that emerges late in the second year. The general capacity is defined structurally as the ability to coordinate two sensorimotor systems into a single skill. Although there seem to be some discontinuities in the emergence of the representational capacity, its development is mostly gradual and continuous.