bluuebunny/crossref_metadata_2025 huggingface dataset:
Serial plasma fibronectin levels in pre‐eclamptic and normotensive women
Authors: Sud S.S. , Gupta I. , Dhaliwal L.K. , Kaur B. , Ganguly N.K.
Published: February 2003

Objective: Endothelial cell damage has been put forward as an underlying factor for development of pre‐eclampsia. This study was carried out to see if fibronectin, which is a marker of endothelial damage, could be used as a marker of pre‐eclampsia. Methods: A longitudinal study was conducted on 100 normotensive primigravidae registered before 20 weeks of gestation. These subjects were followed until delivery and three blood samples were collected, first at registration, i.e. before 20 weeks, second around 28 weeks and third at 36 weeks or later till delivery. Fibronectin levels were assayed by ELISA and women observed for any signs of pre‐eclampsia. Results: Fourteen subjects developed pre‐eclampsia. Fibronectin levels were observed to rise as pregnancy advanced but the rise was significantly higher in subjects who developed pre‐eclampsia. The fibronectin levels were also significantly higher in these 14 subjects even in the first sample, i.e. before 20 weeks of gestation when compared with normotensive subjects (P<0.01). Conclusions: Fibronectin levels could be used as an early valuable biomarker for the development of pre‐eclampsia.
Low‐dose diclofenac potassium in the treatment of episodic tension‐type headache
Authors: Kubitzek Florian , Ziegler Gabrielle , Gold Morris S. , Liu Jiun‐Min H. , Ionescu Elisabeta
Published: February 2003

Background. Several clinical trials have demonstrated that low doses of non‐steroidal anti‐inflammatory drugs relieve episodic tension‐type headache (ETH).

Aims. The aims of this placebo‐controlled study were to determine whether single doses of diclofenac‐K 12.5 and 25 mg effectively relieve ETH in adults and to compare it to ibuprofen 400 mg.

Methods. A single‐dose multicentre, randomised, double‐blind, double‐dummy, clinical trial was conducted at 22 primary care centres in Germany. All subjects had a history of ETH according to the classification of the International Headache Society. Of 684 subjects randomised, 620 used the study drugs for an episode of tension headache occurring within one month after enrolment: diclofenac‐K 12.5 mg (n=160), diclofenac‐K 25 mg (n=156), ibuprofen 400 mg (n=151) and placebo (n=153). The primary efficacy variable was total pain relief, calculated as the time‐weighted sum of the pain relief assessments from baseline to the 3 h evaluation time (TOTPAR‐3).

Results. For TOTPAR‐3, all active treatments were superior to placebo; no statistically significant difference between the three active treatments could be detected. A similar pattern was also observed with regard to TOTPAR‐6 (6 h evaluation time), ≥50%maxTOTPAR at 3 and 6 h, weighted pain intensity difference at 3 and 6 h (SPID‐3; SPID‐6), percentage of patients with complete headache relief at 2 h, end of study global evaluation and time to rescue medication. The number‐needed‐to‐treat (NNT) at 6 h was 4.5 (2.9–9.2) in the ibuprofen 400 mg group, 4.0 (2.8–7.3) in the diclofenac‐K 12.5 mg group and 3.9 (2.7–7.1) in the diclofenac‐K 25 mg group. These differences were not statistically significant.

Conclusion. Diclofenac‐K, administered as single doses of 12.5 and 25 mg effectively relieves ETH and is comparable to ibuprofen 400 mg.
Therapeutic approaches to fibromyalgia syndrome in the United Kingdom: a survey of occupational therapists and physical therapists
Authors: Sim Julius , Adams Nicola
Published: February 2003

Background and purpose. This study sought information from occupational therapists (OTs) and physical therapists (PTs) working in rheumatology in the UK on their usual methods of treatment and management of patients with fibromyalgia syndrome (FMS).

Methods. Data were gathered by self‐completion questionnaire on: work setting; referrals of FMS patients; usual treatment objectives; assessment and treatment approaches; perceived responsiveness of patients; and other perceptions of the management of FMS. Most data were in the form of frequency counts, with some ordinal scales and open responses.

Results. Responses were obtained from 142 therapists (71% response rate), of whom 47 OTs and 39 PTs managed patients with FMS. The foremost therapeutic objective was increased functional ability for OTs, and increased exercise tolerance and general fitness for PTs. Pain reduction or management was rated as the second objective for both groups. An endurance‐based exercise program and energy conservation techniques were the most frequently utilized interventions. Patients with FMS were thought to be ‘moderately responsive’ to physical management. Predictors of outcome were considered to be largely psychosocial, rather than physical, in nature.

Conclusion. These data provide a preliminary profile of current practice in the management of FMS among UK therapists and indicate certain differences in approach between OTs and PTs.
Transcutaneous electrical nerve stimulation (TENS) can reduce postoperative analgesic consumption. A meta‐analysis with assessment of optimal treatment parameters for postoperative pain
Authors: Bjordal Jan Magnus , Johnson Mark I. , Ljunggreen Anne Elisabeth
Published: February 2003

Aim. We investigated the literature of randomised placebo‐controlled trials to find out if transcutaneous electrical nerve stimulation (TENS) or acupuncture‐like transcutaneous electrical nerve stimulation (ALTENS) can reduce analgesic consumption after surgery.

Results. Subgroup analysis for adequate treatment (pulse frequency: 1–8 Hz [ALTENS] or 25–150 Hz [TENS], current intensity: “strong, definite, subnoxious, maximal tolerable” or above 15 mA, and electrode placement in the incision area) were performed. Twenty‐one randomised, placebo‐controlled trials with a total of 1350 patients were identified. For all trials, the mean reduction in analgesic consumption after TENS/ALTENS was 26.5% (range −6 to +51%) better than placebo. Eleven of the trials compromising 964 patients, had reports which stated that a strong, subnoxious electrical stimulation with adequate frequency was administered. They reported a mean weighted reduction in analgesic consumption of 35.5% (range 14–51%) better than placebo. In nine trials without explicit confirmation of sufficient current intensity and adequate frequency, the mean weighted analgesic consumption was 4.1% (range −10 to +29%) in favour of active treatment. The difference in analgesic consumption was significantly (p=0.0002) in favour of adequate stimulation. The median frequencies used in trials with optimal treatment was 85 Hz for TENS and 2 Hz in the only trial that investigated ALTENS.

Conclusion. TENS, administered with a strong, subnoxious intensity at an adequate frequency in the wound area, can significantly reduce analgesic consumption for postoperative pain.
The Red Queen and the Hard Reds: Productivity Growth in American Wheat, 1800–1940
Authors: Olmstead Alan L. , Rhode Paul W.
Published: February 2003

Standard treatments of U.S. agriculture assert that, before the 1930s, productivity growth was almost exclusively the result of mechanization rather than biological innovations. This article shows that U.S. wheat production witnessed wholesale changes in varieties and cultural practices during the nineteenth and early twentieth centuries. Without these changes, vast expanses of the wheat belt could not have sustained commercial production and yields everywhere would have plummeted due to the increasing severity of insects, diseases, and weeds. Revised estimates of Parker and Klein’s productivity calculations indicate that biological innovations contributed roughly half of labor-productivity growth between 1839 and 1909.
From the Counting House to the Modern Office: Explaining Anglo-American Productivity Differences in Services, 1870–1990
Authors: Broadberry Stephen , Ghosal Sayantan
Published: February 2003

The United States overtook Britain in comparative aggregate productivity levels primarily as a result of trends in services rather than trends in industry. This occurred during the transition from customized, low-volume, high-margin business organized on the basis of networks to standardized, high-volume, low-margin business with hierarchical management from the 1870s. This transformation from the counting house to the modern office was dependent on technologies that improved communications and information processing. The technologies were slower to diffuse in Britain as a result of lower levels of education and stronger labor-force resistance to intensification.
Strategic Behavior in Whiskey Distilling, 1887–1895
Authors: Clay Karen , Troesken Werner
Published: February 2003

This article shows that the Whiskey Trust used exclusive dealing and unusually low prices to deter entry and competition. Evidence of this is based on a unique dataset that allows us to estimate a firm-level demand curve for the trust, and to construct direct estimates of marginal cost. This article also shows that the strategies employed by the trust failed to deter entry. Market structure and state-level antitrust enforcement account for the failure of these strategies.
The Development of Intermediation in French Credit Markets: Evidence from the Estates of Burgundy
Authors: Potter Mark , Rosenthal Jean-Laurent
Published: February 2003

We document how intermediaries shaped markets or, conversely, how market institutions constrained intermediaries. In Dijon, where the Estates of Burgundy’s debt amounted to nearly half of all bonds in that small market, there was limited need for intermediaries. In the 1740s the borrowing needs of the province expanded, and the estates began to borrow in Paris, where their debt remained a small fraction of the market, and where they relied on notaries to place their bonds and to create a secondary market. These developments assured the estates’ capacity to borrow and thus Burgundian autonomy from the French Crown.
Boom-or-Bust Commodities and Industrialization in Pre–World War II Malaya
Authors: Huff W. G.
Published: February 2003

This article links the terms of trade, money supply, labor market, and money and credit markets to explore a puzzle in Malayan economic history: why, despite rapid growth and high per capita income, did pre–World War II Malaya industrialize so little? A range of data is drawn together to show how for Malayan manufacturers economic boom was accompanied by precipitate deterioration in the real exchange rate, while in a slump credit contracted sharply and with it the size of the Malayan market for manufactures. Analysis of Malayan experience may be relevant for understanding slight industrialization elsewhere in Southeast Asia.
Empathy: Its ultimate and proximate bases
Authors: Preston Stephanie D. , de Waal Frans B. M.
Published: February 2003

There is disagreement in the literature about the exact nature of the phenomenon of empathy. There are emotional, cognitive, and conditioning views, applying in varying degrees across species. An adequate description of the ultimate and proximate mechanism can integrate these views. Proximately, the perception of an object's state activates the subject's corresponding representations, which in turn activate somatic and autonomic responses. This mechanism supports basic behaviors (e.g., alarm, social facilitation, vicariousness of emotions, mother-infant responsiveness, and the modeling of competitors and predators) that are crucial for the reproductive success of animals living in groups. The Perception-Action Model (PAM), together with an understanding of how representations change with experience, can explain the major empirical effects in the literature (similarity, familiarity, past experience, explicit teaching, and salience). It can also predict a variety of empathy disorders. The interaction between the PAM and prefrontal functioning can also explain different levels of empathy across species and age groups. This view can advance our evolutionary understanding of empathy beyond inclusive fitness and reciprocal altruism and can explain different levels of empathy across individuals, species, stages of development, and situations.
The relationship between object manipulation and language development in Broca's area: A connectionist simulation of Greenfield's hypothesis
Authors: Reilly Ronan G.
Published: February 2003

In her Behavioral and Brain Sciences target article, Greenfield (1991) proposed that early in a child's development Broca's area may serve the dual function of coordinating object assembly and organizing the production of structured utterances. As development progresses, the upper and lower regions of Broca's area become increasingly specialized for motor coordination and speech, respectively. This commentary presents a connectionist simulation of aspects of this proposal. The results of the simulation confirm the main thrust of Greenfield's argument and suggest that an important impetus for the developmental differentiation in Broca's area may be the increasing complexity of the computational demands made upon it.
Hyperbolic discounting lets empathy be a motivated process
Authors: Ainslie George , Monterosso John
Published: February 2003

The Perception-Action Model (PAM) is a cogent theory of how organisms get information about others' experiences. However, such a stimulus-driven mechanism does not handle well the complex choices that humans face about how to respond to this information. Hyperbolic reward discounting permits a reward-driven mechanism for both how aversive empathic experiences can compete for attention and how pleasurable empathic experiences are constrained.
Are the dorsal/ventral pathways sufficiently distinct to resolve perceptual theory?
Authors: Andersen George J.
Published: February 2003

The author argues that the theory of a dorsal/ventral stream for visual processing can be used to reconcile the constructivist and direct perception theories. My commentary discusses neurophysiological and psychophysical studies that run counter to the view. In addition, the central issue of debate between the constructionist and direct perception approaches regarding what is visual information is discussed.
Author's Response
Authors: Greenfield Patricia M.
Published: February 2003

Ronan Reilly's connectionist simulation both strengthens and advances the theoretical model presented in my 1991 target article, “Language, Tools, and Brain: The Ontogeny and Phylogeny of Hierarchically Organized Sequential Behavior.” Reilly has tested the whole ontogenetic model with a single simulation study explicitly planned for this purpose. His methodology has established that the various components of the theoretical model imply and are compatible with one another. It has also indicated how learning can actualize a pre-established ontogenetic sequence of combining lingusitic symbols and objects. His simulation suggests that the acquisition of linguistic speech may be facilitated by experience with object manipulation, but not vice versa. This hypothesis can and should be empirically tested through research on behavioral development in the two domains. Finally, Reilly has simulated brain architecture, as well as neural learning. His simulation therefore shows how the development of language and object manipulation can result from an interaction between preprogrammed neural architecture (analogous to network architecture) and experience (analogous to the network's training cycles).
The role of empathy in the formation and maintenance of social bonds
Authors: Anderson Cameron , Keltner Dacher
Published: February 2003

A primary function of empathy is to help individuals form and maintain social bonds. Empathy should thus occur only when individuals seek to solidify social bonds, and not in response to any opportunity to process others' emotions. Empathy should also involve only certain types of emotion – specifically, emotions that facilitate social bonds – and not any and all types of emotion.
When is movement controlled by the dorsal stream?
Authors: Binsted Gordon , Carlton Les G.
Published: February 2003

Our commentary focuses on the functional link between the ventral and dorsal systems implied by Norman, as they relate to overt movement. While issues relating to space perception and size constancy are the primary justification for this dual-process theory, the philosophical extensions of this approach are less consistent with examination of motor control and, in particular, motor learning.
Emotion-specific clues to the neural substrate of empathy
Authors: Atkinson Anthony P.
Published: February 2003

Research only alluded to by Preston & de Waal (P&deW) indicates the disproportionate involvement of some brain regions in the perception and experience of certain emotions. This suggests that the neural substrate of primitive emotional contagion has some emotion-specific aspects, even if cognitively sophisticated forms of empathy do not. Goals for future research include determining the ways in which empathy is emotion-specific and dependent on overt or covert perception.
A better understanding of inference can reconcile constructivist and direct theories
Authors: Braunstein Myron L.
Published: February 2003

The attempt to relate distinctions in perceptual theory to different physiological systems leads to numerous exceptions and inconsistencies. A more promising approach to the reconciliation of constructivist theory and direct perception is to recognize that perception does involve inference, as the constructivists insist, but that inference is a process in logic that does not require unconscious reasoning and need be no more thought-like than resonance.
Empathy as a special case of emotional mediation of social behavior
Authors: Aureli Filippo , Schaffner Colleen M.
Published: February 2003

Empathy can be viewed as an intervening variable to explain complex webs of causation between multiple factors and the resulting responses. The mediating role of emotion, implicit in the concept of an intervening variable, can be at the basis of the flexibility of empathic responses. Knowledge of the underlying neurophysiological mechanisms is needed for empathy to be considered as a biologically functional intervening variable.
Two visual systems but only one theory of perception
Authors: Burke Darren , Hayward William G.
Published: February 2003

The parallel drawn by Norman between the dorsal and ventral systems and direct and indirect approaches is based on two misrepresentations of the direct approach – that it is concerned only with the unconscious control of action, and that it cannot explain learning. We propose a way of understanding the visual system differences from within the direct approach.
Conceptual space as a connection between the constructivist and the ecological approaches in a robot vision system
Authors: Chella Antonio
Published: February 2003

The conceptual space< (Gärdenfors 2000) is discussed as a representation structure that connects the constructivist and the ecological vision subsystems in an operating autonomous robot based on computer vision.
Developmental processes in empathy
Authors: Bard Kim A.
Published: February 2003

In recent years, explanations of primate cognition highlighted clever arguments, rather than different ability. In the target article, definitions unify, explanations rely on basic nervous system functioning, theory is built on data that fit, and the emphasis is on evolutionary continuities. This commentary describes complexities inherent in the development of empathy that are not accounted for in Preston & de Waal's theory.
Perception, learning, and judgment in ecological psychology: Who needs a constructivist ventral system?
Authors: Cooper Clinton , Michaels Claire F.
Published: February 2003

Norman's identification of a ventral system embodying a constructivist theory of perception is rejected in favor of an ecological theory of perception and perceptual learning. We summarize research showing that a key motivation for the ventral-constructivist connection, percept-percept coupling, confuses perceptual and post-perceptual processes
Empathy: Common sense, science sense, wolves, and well-being
Authors: Bekoff Marc
Published: February 2003

Empathy is likely more widely distributed among animals than many researchers realize or perhaps are willing to admit. Studies of social carnivores, other group-living animals, and communication via different modalities will help us learn more about the evolutionary roots and behavioral, sensory, and cognitive underpinnings of empathy, including what it means to have a sense of self. There are also important implications for debates about animal well-being.
Invariants and cues
Authors: Cutting James E.
Published: February 2003

The concepts of invariants and cues are useful, as are those of dorsal and ventral streams, but Norman overgeneralizes when interweaving them. Cues are not confined to identification tasks, invariants not to action, and both can be learned.
Empathy: A unitary circuit or a set of dissociable neuro-cognitive systems?
Authors: Blair James R. , Perschardt Karina S.
Published: February 2003

We question whether empathy is mediated by a unitary circuit. We argue that recent neuroimaging data indicate dissociable neural responses for different facial expressions as well as for representing others' mental states (Theory of Mind, TOM). We also argue that the general empathy disorder considered characteristic of autism and psychopathy is not general but specific for each disorder.
Ecological and constructivist approaches and the influence of illusions
Authors: de Grave Denise D. J. , Smeets Jeroen B. J. , Brenner Eli
Published: February 2003

Norman tries to link the ecological and constructivist approaches to the dorsal and ventral pathways of the visual system. Such a link implies that the distinction is not only one of approach, but that different issues are studied. Norman identifies these issues as perception and action. The influence of contextual illusions is critical for Norman's arguments. We point out that fast (dorsal) actions can be fooled by contextual illusions while (ventral) perceptual judgements can be insensitive to them. We conclude that both approaches can, in principle, be used to study visual information processing in both pathways.
Peers, cooperative play, and the development of empathy in children
Authors: Brownell Celia A. , Zerwas Stephanie , Balaram Geetha
Published: February 2003

Cooperative peer play emerges in the second year of life. How applicable is Preston & de Waal's (P&deW's) model to the empathic processes in cooperative play? Empathic responses during peer play are more general than they propose, and more dependent on mental state understanding. Moreover, peer play forces children to reason about others' feelings, possibly serving as a unique mechanism for empathy development.
Evolutionary and intellectual antecedents of primate visual processing streams
Authors: Ellard Colin G.
Published: February 2003

The main function of vision in many animals is to control movement. In rodents, some visuomotor acts require the construction of models of the external world while others rely on Gibsonian invariants. Such findings support Norman's dual processing approach but it is not clear that the two types of processing rely on homologs of visual processing streams described in primates.
A fast ventral stream or early dorsal-ventral interactions?
Authors: Elliott Digby , Tremblay Luc , Welsh Timothy N.
Published: February 2003

Several lines of evidence indicate that rapid target-aiming movements, involving both the eyes and hand, can be biased by the visual context in which the movements are performed. Some of these contextual influences carry-over from trial to trial. This research indicates that dissociation between the dorsal and ventral systems based on speed, conscious awareness, and frame of reference is far from clear.
A complete theory of empathy must consider stage changes
Authors: Commons Michael Lamport , Wolfsont Chester Arnold
Published: February 2003

A sequential, hierarchical stage model of empathy can account for a comprehensive range of empathic behaviors. We provide an illustrative table, “Stages of Empathy,” to demonstrate how increasingly complex empathic behaviors emerge at each stage, beginning with the infant's “automatic empathy” and ending with the advanced adult's “coconstruction of empathetic reality.”
Constructivist and ecological approaches in tactual perception
Authors: Gentaz Edouard , Hatwell Yvette , Streri Arlette
Published: February 2003

Constructivist and ecological approaches are also observed in tactile perception studies. The question is whether identification and localization are dissociated in the tactile modality as well, and whether Norman's conception may be generalized to the field of touch. An analogue to blindsight was evidenced in passive touch, but no such dissociation was observed in active touch. A study is in progress in this domain.
Deconstructing empathy
Authors: Constantino John N.
Published: February 2003

Under Preston & de Waal's proposed model, empathy might be regarded as everything that determines the quality of a social relationship. Although the authors provide a useful heuristic for understanding relationships, clinical research efforts with a somewhat narrower focus have provided some additional insights into this topic, which might lead to testable hypotheses regarding the neurobiology of empathy.
Recognising actions
Authors: Green Patrick R. , Pollick Frank E.
Published: February 2003

The ability to recognise the actions of conspecifics from displays of biological motion is an essential perceptual capacity. Physiological and psychological evidence suggest that the visual processing of biological motion involves close interaction between the dorsal and ventral systems. Norman's strong emphasis on the functional differences between these systems may impede understanding of their interactions.
Too early for a neuropsychology of empathy
Authors: Davis Hank
Published: February 2003

To date, a wide range of interdisciplinary scholarship has done little to clarify either the why or the how of empathy. Preston & de Waal (P&deW) attempt to remedy this, although it remains unclear whether empathy consists of two discrete processes, or whether a perceptual and motor component are joined in some sort of behavioral inevitability. Although it is appealing to offer a neuroanatomy of empathy, the present level of neuropsychology may not support such reductionism.
Direct information on the cutting room floor
Authors: Hochberg Julian
Published: February 2003

Norman's assigning of the constructivist percept-percept coupling approach and the ecological affordances approach to the ventral and dorsal visual systems, respectively, makes a more workable metatheory than each taken separately, but brings both under closer inspection.
Distinctions among various modes of empathy-related reactions: A matter of importance in humans
Authors: Eisenberg Nancy
Published: February 2003

Preston & de Waal minimized differences among constructs such as empathy, sympathy, and personal distress. However, such distinctions have been shown to relate differently to altruistic behavior. Moreover, although the authors discussed the role of regulation in empathy, they did not consider the possibility that sometimes empathy is not well-regulated and likely leads to personal distress rather than sympathy.
A wider view of the spatial mode of vision
Authors: Ingle David
Published: February 2003

The two modes of visual processing “localizing” versus “identifying” as expressed by four authors in 1967 are more encompassing than the “two visual systems” dichotomies posed by later theorists. Norman's view of parietal cortex functions of vision seems much too narrow.
Emotional and cognitive processing in empathy and moral behavior
Authors: Eslinger Paul J. , Moll Jorge , de Oliveira-Souza Ricardo
Published: February 2003

Within the perception-action framework, the underlying mechanisms of empathy and its related processes of moral behavior need to be investigated. fMRI studies have shown different frontal cortex activation patterns during automatic processing and judgment tasks when stimuli have moral content. Clinical neuropsychological studies reveal different patterns of empathic alterations after dorsolateral versus orbital frontal cortex damage, related to deficient cognitive and emotional processing. These processing streams represent different neural levels and mechanisms underlying empathy.
On invariant-sensitive graspers and cue-sensitive perceivers
Authors: Kingdom Frederick A. A.
Published: February 2003

I argue that Norman's thesis works in sofaras one is prepared to be lax about the alleged congruency between “ecological” and “dorsal,” and unconcerned by the results of recent studies showing that grasping movements are subject to the same geometric distortion illusions as perceptual judgements.
The mirror matching system: A shared manifold for intersubjectivity
Authors: Gallese Vittorio , Ferrari Pier Francesco , Umiltà Maria Alessandra
Published: February 2003

Empathy is the phenomenal experience of mirroring ourselves into others. It can be explained in terms of simulations of actions, sensations, and emotions which constitute a shared manifold for intersubjectivity. Simulation, in turn, can be sustained at the subpersonal level by a series of neural mirror matching systems.
Cognitive empathy presupposes self-awareness: Evidence from phylogeny, ontogeny, neuropsychology, and mental illness
Authors: Gallup Gordon G. , Platek Steven M.
Published: February 2003

We argue that cognitive empathy and other instances of mental state attribution are a byproduct of self-awareness. Evidence is brought to bear on this proposition from comparative psychology, early child development, neuropsychology, and abnormal behavior.
The dual route hypothesis in visual cognition: Why a developmental approach is necessary
Authors: Mareschal Denis , Kaufman Jordy
Published: February 2003

Norman presents intriguing arguments in support of a mapping between ecological and constructivist visual cognition, on the one hand, onto the dorsal ventral dual route processing hypothesis, on the other hand. Unfortunately, his account is incompatible with developmental data on the functional emergence of the dorsal and ventral routes. We argue that it is essential for theories of adult visual cognition to take constraints from development seriously.
Empathy, simulation, and PAM
Authors: Gordon Robert M.
Published: February 2003

The wealth of important and convergent evidence discussed in the target article contrasts with the poorly conceived theory put forward to explain it. The simulation theory does a better job of explaining how automatic “mirroring” mechanisms might work together with high-level cognitive processes. It also explains what the authors' PAM theory merely stipulates.
One visual system with two interacting visual streams
Authors: McCarley Jason S. , DiGirolamo Gregory J.
Published: February 2003

Norman's aim to reconcile two longstanding and seemingly opposed philosophies of perception, the constructivist and the ecological, by casting them as approaches to complementary subsystems within the visual brain is laudable. Unfortunately, Norman overreaches in attempting to equate direct perception with dorsal/unconscious visual processing and indirect perception with ventral/conscious visual processing. Even a cursory review suggests that the functional and neural segregation of direct and indirect perception is not as clear as the target article would suggest.
Emotion: The relation between breadth of definition and explanatory power
Authors: Hinde Robert A.
Published: February 2003

Attempts to integrate diverse phenomena in terms of common processes are much needed in psychology, but definitional precision is a necessary preliminary to explanation. It is also preferable to use caution in juxtaposing concepts from different realms of discourse.
Where does perception end and when does action start?
Authors: McFarland Dennis J.
Published: February 2003

Currently there is considerable interest in the notion that dorsal and ventral visual systems might differ in their specializations for thought and action. Behavior invariably involves multiple processes such as perception, judgment, and response execution. It is not clear that characteristics of the dorsal and ventral processing streams, as described by Norman, are entirely of a perceptual nature.
How automatic and representational is empathy, and why
Authors: Hoffman Martin L.
Published: February 2003

The claim that empathy is both automatic and representational is criticized as follows: (a) five empathy-arousing processes ranging from conditioning and mimicry to prospective-taking show that empathy can be either automatic or representational, and only under certain circumstances, both; (b) although automaticity decreases, empathy increases with age and cognitive development; (c) observers' causal attributions can shift rapidly and produce more complex empathic responses than the theory allows.
The dorsal system and the ecological self
Authors: Neisser Ulric
Published: February 2003

Perception, as Gibson described it – picking up information that specifies the real local situation – includes not only perceiving affordances and controlling small movements, but also seeing the large-scale environmental layout and the position/movement of the “ecological self.” If the dorsal cortical system is also responsible for that very significant achievement, its activity must be at least partly conscious.
Mirror neurons, the insula, and empathy
Authors: Iacoboni Marco , Lenzi Gian Luigi
Published: February 2003

Neurophysiological studies in monkeys and neuroimaging studies in humans support a model of empathy according to which there exists a shared code between perception and production of emotion. The neural circuitry critical to this mechanism is composed of frontal and parietal areas matching the observation and execution of action, and interacting heavily with the superior temporal cortex. Further, this cortical system is linked to the limbic system by means of an anterior sector of the human insular lobe.
Elucidation of the brain correlates of cognitive empathy and self-awareness
Authors: Keenan Julian Paul , Wheeler Mark A.
Published: February 2003

Self-awareness is thought to be tied to processes of higher-order perspective taking including empathy. These abilities appear to be reserved for humans, great apes, and possibly, dolphins. Recent examinations reveal that both self-awareness and empathy may have origins in the right hemisphere. It is possible that, as in language, lateralization plays a key role in the development of higher-order perspective taking and self-awareness.
The ventral stream offers more affordance and the dorsal stream more memory than believed
Authors: Postma Albert , van der Lubbe Rob , Zuidhoek Sander
Published: February 2003

Opposed to Norman's proposal, processing of affordance is likely to occur not solely in the dorsal stream but also in the ventral stream. Moreover, the dorsal stream might do more than just serve an important role in motor actions. It supports egocentric location coding as well. As such, it would possess a form of representational memory, contrary to Norman's proposal.
Similarity versus familiarity: When empathy becomes selfish
Authors: Khalil Elias L.
Published: February 2003

Preston & de Waal conflate familiarity with similarity in their attempt to account for empathy. If distinguished, we may have at hand two different kinds of empathy: egocentric empathy and empathy proper.
Berkeley, Helmholtz, the moon illusion, and two visual systems
Authors: Ross Helen E.
Published: February 2003

Berkeley and Helmholtz proposed different indirect mechanisms for size perception: Berkeley, that size was conditioned to various cues, independently of perceived distance; Helmholtz, that it was unconsciously calculated from angular size and perceived distance. The geometrical approach cannot explain size-distance paradoxes (e.g., moon illusion). The dorsal/ventral solution is dubious for close displays and untestable for far displays.
Empathy requires the development of the self
Authors: Lewis Michael
Published: February 2003

Two major problems exist in studying development: Similar behaviors do not need to reflect the same underlying process, different behaviors can reflect the same process; earlier behaviors do not necessarily lead to later behaviors. Empathy, rather than social contagion, is supported by different processes; contagion supported by prewired species behavior, empathy by cognitions, in particular, the cognitions about the self – a meta-representation.
Integrating constructivist and ecological approaches
Authors: Shebilske Wayne
Published: February 2003

Norman relates two theoretical approaches, the constructivist and ecological, to two cortical visual streams, the ventral and dorsal systems, respectively. This commentary reviews a similar approach in order to increase our understanding of complex skill development and to advance Norman's goal of stimulating and guiding research on the two theoretical approaches and the two visual systems.
The Perception-Action Model of empathy and psychopathic “cold-heartedness”
Authors: Mealey Linda , Kinner Stuart
Published: February 2003

The Perception-Action Model of empathy (PAM) is both sufficiently broad and sufficiently detailed to be able to describe and accommodate a wide range of phenomena – including the apparent “cold-heartedness” or lack of empathy of psychopaths. We show how the physiological, cognitive, and emotional elements of the PAM map onto known and hypothesized attributes of the psychopathic personality.
Two visual systems must still perceive events
Authors: Shull J. Alex , Bingham Geoffrey P.
Published: February 2003

Perception of (and during) events is a necessary feature of any perceptual theory. Norman's dual-process approach cannot account for the perception of events without substantial interactions between the dorsal and ventral systems. These interactions, as outlined by Norman, are highly problematical. The necessity for interactions between the two systems makes the distinction useless.
Norman's dual model in a broader context
Authors: Toates Frederick
Published: February 2003

This commentary suggests how Norman's dual control model of vision can be fitted into a broader general model of the control of behaviour by direct (on-line) and indirect (off-line) processes. Some general principles of behavioural organization, development, and competition are described and their specific application to vision is noted.
Understanding other's emotions: From affective resonance to empathic action
Authors: Parr Lisa A.
Published: February 2003

Empathy is a developmental process whereby individuals come to understand the emotional states of others. While the exact nature of this process remains unknown, PAM's utility is that it establishes empathy along a continuum of behavior ranging from emotional contagion to cognitive forms, a very useful distinction for understanding the phylogeny and ontogeny of this important process. The model will undoubtedly fuel future research, especially from comparative domains where data are most problematic.
On the development of the two visual systems
Authors: van der Kamp John , Savelsbergh Geert J. P.
Published: February 2003

Norman's reconciliation of the two theories of perception is challenged because it directly leads to the nature-nurture dichotomy in the development of the two visual systems. In contrast, the proposition of a separate development of the two visual systems may be better understood as involving different types of information that follow a distinct temporal sequence.
Various kinds of empathy as revealed by the developing child, not the monkey's brain
Authors: Rochat Philippe
Published: February 2003

The comparative study of empathy should be based on the developmental taxonomy of vicarious experiences offered by the abundant literature on infants and children's cognitive, social, and emotional development. Comparative research on the topic should refer to the various kinds of empathy emerging in an orderly fashion early in human development.
Adequacy and utility of the dual-process approach to perception: Time (and research) will tell
Authors: Norman Joel
Published: February 2003

My response and reactions to the quite diverse commentaries are presented. Among the topics covered are a response to holders of the ecological viewpoint; memory and learning in the two perceptual systems; development of the two systems; biological motion; size and distance perception; illusion and the two systems; and several others. It is suggested that the dual-process approach is a viable working theory of space perception and, perhaps, of other types of perception as well. Hopefully, future research will enhance it with added refinements and variations on the original theme.
Psychobiological basis of empathy
Authors: Schulkin Jay
Published: February 2003

Empathy represents one of the basic forms of human expression. Empathy evolved to facilitate social behavior. The perception action model, extended to empathy, is an exciting paradigm in which to undertake contemporary cognitive and comparative neuroscience. It renders the perception of events as an active affair, both when watching others, and when performing actions.
Perception-action links and the evolution of human speech exchange
Authors: Wilson Thomas P. , Wilson Margaret
Published: February 2003

A perception-action system may underlie the mechanisms by which human speech exchange in social interaction is managed, as well as the evolutionary precursors of these mechanisms in closely related species. Some phenomena of interaction well-studied by sociologists are suggested as a point of departure for further research.
Empathy: Each is in the right – hopefully, not all in the wrong
Authors: Preston Stephanie D. , de Waal Frans B. M.
Published: February 2003

Only a broad theory that looks across levels of analysis can encompass the many perspectives on the phenomenon of empathy. We address the major points of our commentators by emphasizing that the basic perception-action process, while automatic, is subject to control and modulation, and is greatly affected by experience and context because of the role of representations. The model can explain why empathy seems phenomenologically more effortful than reflexive, and why there are different levels of empathy across individuals, ages, and species.
Molecules and Clusters in Intense Laser Fields
Authors: Bauer Dieter
Published: February 2003

The interaction of intense laser light with molecules and clusters
is a rapidly evolving research area. Its attraction lies in both the
underlying fundamental physics and the prospects for applications. The
interaction of intense laser light with rare-gas clusters, for instance,
leads to megaelectron volt electrons, multikiloelectron volt ions, and
bright X-ray emission. In laser-irradiated D2 clusters,
thermonuclear fusion has been achieved.
Experimental investigations of multiple weak shock waves
induced by intense heavy ion beams in solid matter
Authors: CONSTANTIN C. , DEWALD E. , NIEMANN C. , TAHIR N.A. , SHUTOV A. , KOZYREVA A. , SCHLEGEL T. , UDREA S. , VARENTSOV D. , JACOBY J. , TAUSCHWITZ A. , FUNK U.N. , NEUNER U. , SPILLER P. , HOFFMANN D.H.H
Published: February 2003

The dynamics of low entropy weak shock waves induced by heavy
ion beams in solid targets was investigated by means of a schlieren
technique. The targets consist of a metallic absorber for the
beam energy deposition followed by a plexiglass block for optical
observations. Multiple waves propagating with supersonic velocities
at 15 kbar pressures were observed in the plexiglass, for pressures
of up to 70 kbar numerically calculated in the absorbers. Pressures
in the megabar ranges are predicted for a near future beam upgrade,
enabling studies of phase transition to metallic states of H,
Kr, and Xe.
Plasma-based studies with intense X-ray and particle beam
sources
Authors: LEE R.W. , BALDIS H.A. , CAUBLE R.C. , LANDEN O.L. , WARK J.S. , NG A. , ROSE S.J. , LEWIS C. , RILEY D. , GAUTHIER J.-C. , AUDEBERT P.
Published: February 2003

The construction of short pulse (<200 fs) tunable X-ray
laser sources based on the X-ray free electron laser (XFEL)
concept will be a watershed for plasma-based and warm dense
matter research. These new fourth generation light sources will
have extremely high fields and short wavelengths (∼0.1 nm)
with peak spectral brightnesses 1010 greater than
third generation sources. Further, the high intensity upgrade
of the GSI accelerator facilities will lead to specific energy
depositions up to 200 kJ/g and temperatures between 1 and
10 eV at almost solid-state densities, enabling interesting
experiments in the regime of nonideal plasmas, such as the
evolution of intense ion beams in the interior of a Jovian planet.
Below we discuss several applications: the creation of warm dense
matter (WDM) research, probing of near solid density plasmas, and
laser–plasma spectroscopy of ions in plasmas. The study of
dense plasmas has been severely hampered by the fact that laser-based
methods have been unavailable and these new fourth generation sources
will remove these restrictions.
Guest Editor's Preface: International Heavy Ion Inertial
Fusion 2002 Special Issue
Authors: Sharkov Boris
Published: February 2003

This issue of Laser and Particle Beams contains the papers
submitted for publication by participants of the 14th International Heavy
Ion Inertial Fusion (HIF) Symposium held in Moscow, May 26–31, 2002.
This conference was organized by State Research Center of Russian Federation,
Institute for Theoretical and Experimental Physics, Moscow, under the auspices
of the International Atomic Energy Agency, Beam Plasma and Inertial Fusion
Section of the European Physical Society, and Accelerator Council of Russian
Academy of Science. The symposium was supported by the Ministry of Atomic
Energy of Russian Federation, Russian Academy of Science, Russian Foundation
for Basic Research, International Science, and Technology Center, and by GSI
Darmstadt.
Overview of virtual national laboratory objectives, plans,
and projects
Authors: LOGAN B.G. , CELATA C.M. , KWAN J.W. , LEE E.P. , LEITNER M. , SEIDL P.A. , YU S.S. , BARNARD J.J. , FRIEDMAN A. , MEIER W.R. , DAVIDSON R.C.
Published: February 2003

Significant experimental and theoretical progress has been
made in the U.S. heavy ion fusion program on high-current sources,
transport, and focusing. Currents over 200 mA have been transported
through a matching section and 10 half-lattice periods with
electric quadrupoles. An experiment shows control of high-beam
current with an aperture, while avoiding secondary electrons.
New theory and simulations of the neutralization of intense
beam space charge with plasma in various focusing chamber
configurations predict that near-emittance-limited beam focal
spot sizes can be obtained even with beam perveance (ratio of
beam space potential to ion energy) >10× higher than
in earlier HIF focusing experiments. Progress in a new focusing
experiment with plasma neutralization up to 10−3
perveance, and designs for a next-step experiment to study beam
brightness evolution from source to target are described.