A hypothesis about sensorimotor integration (the λ model) is described and applied to movement control and kinesthesia. The central idea is that the nervous system organizes positional frames of reference for the sensorimotor apparatus and produces active movements by shifting the frames in terms of spatial coordinates. Kinematic and electromyographic patterns are not programmed, but emerge from the dynamic interaction among the system s components, including external forces within the designated frame of reference. Motoneuronal threshold properties and proprioceptive inputs to (...) motoneurons may be cardinal components of the physiological mechanism that produces positional frames of reference. The hypothesis that intentional movements are produced by shifting the frame of reference is extended to multi-muscle and multi-degrees-of-freedom systems with a solution of the redundancy problem that allows the control of a joint alone or in combination with other joints to produce any desired limb configuration and movement trajectory. The model also implies that for each motor behavior, the nervous system uses a strategy that minimizes the number of changeable control variables and keeps the parameters of these changes invariant. Examples are provided of simulated kinematic and electromyographic signals from single- and multi-joint arm movements produced by suggested patterns of control variables. Empirical support is provided and additional tests of the model are suggested. The model is contrasted with others based on the ideas of programming of motoneuronal activity, muscle forces, stiffness, or movement kinematics. (shrink)

The basic concepts of motor control formulated in our target article were derived from specific experiments, a fact which is disregarded in Dalenoort's comments. A purely academic approach to motor control may not result in a clearer understanding of control concepts.

The cerebellum probably obeys the rules of sensorimotor integration common in the nervous system. One such a rule is formulated: the nervous system organizes spatial frames of reference for the sensorimotor apparatus and produces voluntary movements by shifting their origin points. We give examples of spatial frames of reference for different single- and multi-joint movements including locomotion and also illustrate that the process of motor development and learning may depend critically on the formation of appropriate frames of reference and the (...) organism's ability to manage them. We suggest that a solution to the problem of sensorimotor integration may not be trivial and may actually change the mental and experimental paradigms used in the understanding of the cerebellum and other brain structures, [HOUK et al.; SIMPSON et al.; SMITH; TIIACH]. (shrink)

The information required for perception may be available in the energy arrays that stimulate sensory organs but in a form not directly suitable for the planning and execution of the organism's actions in the environment. The requisite form of information is obtained, with no loss of adequate perception, by representation of sensory stimuli in frames of reference determined by internal control signals producing actions. This process seems evolutionarily advantageous but makes perception essentially non-direct, regardless of the degree of intra- or (...) inter-modal sensory integration. (shrink)

Exclusively focused on data that are consistent with the proposed ideas, the target article misses an opportunity to review data that are inconsistent with them. Weaknesses of the emulation theory become especially evident when one tries to incorporate physiologically realistic muscle and reflex mechanisms into it. In particular, it fails to resolve the basic posture-movement controversy.

Understanding of the λ model has greatly increased in recent years as evidenced by most of the commentaries. Some commentators underscored the potential of the model to integrate aspects of different sensorimotor systems in the production of movement. Other commentators focused on not-yet-fully-developed parts of the model. A few persisted in misunderstanding some of its basic concepts, and on these grounds they reject it. In responding to commentaries we continue to elaborate on some fundamental points of the model, especially control (...) variables, the idea of movement production by shifting the positional frame of reference and the hypothesis of biomechanical correspondence in motor control. We also continue to develop our ideas on the intrinsic generation of the frame of reference associated with external space and utilized for the control of arm movement and locomotion. The dynamic principles underlying the model are discussed in light of the dynamical systems approach. (shrink)

It is proposed here that Webb's ideas about robots as possible models of animals need some rethinking. In our view, even though widely used biorobotics strategies are fairly successful at reproducing the macroscopic behavior of biological systems, there are still several problems unresolved on the side of robotics as well as biology. Both mathematical and hardware-like robotics models should be feasible physiologically. Control principles elaborated in robotics are not necessarily applied to biological control systems. Although observations of flying birds inspired (...) aerodynamics and thus modern airplanes, little knowledge has been added to the neurophysiological principles underlying flight in birds. Chess playing computers might outperform most chess players, but they cannot be considered as physiologically feasible models of human thinking. (shrink)

Little is known about the mechanisms by which psychology graduate programs transmit responsible conduct of research (RCR) values. A national sample of 968 current students and recent graduates of mission-diverse doctoral psychology programs completed a Web-based survey on their research ethics challenges, perceptions of RCR mentoring and department climate, whether they were prepared to conduct research responsibly, and whether they believed psychology as a discipline promotes scientific integrity. Research experience, mentor RCR instruction and modeling, and department RCR policies predicted student (...) RCR preparedness. Mentor RCR instruction, department RCR policies, and faculty modeling of RCR behaviors predicted confidence in the RCR integrity of the discipline. Implications for training are discussed. (shrink)

Theories of emotion have often maintained artificial boundaries: for instance, that cognition and emotion are separable, and that an emotion concept is separable from the emotional events that comprise its category (e.g. “fear” is distinct from instances of fear). Over the past several years, research has dissolved these artificial boundaries, suggesting instead that conceptual construction is a domain-general process—a process by which the brain makes meaning of the world. The brain constructs emotion concepts, but also cognitions and perceptions, all in (...) the service of guiding action. In this view, concepts are multimodal constructions, dynamically prepared from a set of highly variable instances. This approach obviates old questions (e.g. how does cognition regulate emotion?) but generates new ones (e.g. how does a brain learn emotion concepts?). In this paper, we review this constructionist, predictive coding account of emotion, considering its implications for health and well-being, culture and development. (shrink)

Fred Feldman's fascinating new book sets out to defend hedonism as a theory about the Good Life. He tries to show that, when carefully and charitably interpreted, certain forms of hedonism yield plausible evaluations of human lives. Feldman begins by explaining the question about the Good Life. As he understands it, the question is not about the morally good life or about the beneficial life. Rather, the question concerns the general features of the life that is good in (...) itself for the one who lives it. Hedonism says (roughly) that the Good Life is the pleasant life. After showing that received formulations of hedonism are often confused or incoherent, Feldman presents a simple, clear, coherent form of sensory hedonism that provides a starting point for discussion. He then presents a catalogue of classic objections to hedonism, coming from sources as diverse as Plato, Aristotle, Brentano, Ross, Moore, Rawls, Kagan, Nozick, Brandt, and others. One of Feldman's central themes is that there is an important distinction between the forms of hedonism that emphasize sensory pleasure and those that emphasize attitudinal pleasure. Feldman formulates several kinds of hedonism based on the idea that attitudinal pleasure is the Good. He claims that attitudinal forms of hedonism - which have often been ignored in the literature -- are worthy of more careful attention. Another main theme of the book is the plasticity of hedonism. Hedonism comes in many forms. Attitudinal hedonism is especially receptive to variations and modifications. Feldman illustrates this plasticity by formulating several variants of attitudinal hedonism and showing how they evade some of the objections. He also shows how it is possible to develop forms of hedonism that are equivalent to the allegedly anti-hedonistic theory of G. E. Moore and the Aristotelian theory according to which the Good Life is the life of virtue, or flourishing. He also formulates hedonisms relevantly like the ones defended by Aristippus and Mill. Feldman argues that a carefully developed form of attitudinal hedonism is not refuted by objections concerning 'the shape of a life'. He also defends the claim that all of the alleged forms of hedonism discussed in the book genuinely deserve to be called 'hedonism'. Finally, after dealing with the last of the objections, he gives a sketch of his hedonistic vision of the Good Life. (shrink)

This text presents a clear and philosophically sound method for identifying, interpreting, and evaluating arguments as they appear in non-technical sources. It focuses on a more functional, real-world goal of argument analysis as a tool for figuring out what is reasonable to believe rather than as an instrument of persuasion. Methods are illustrated by applying them to arguments about different topics as they appear in a variety of contexts - e.g., newspaper editorials and columns, short essays, informal reports of scientific (...) results, etc. (shrink)

Face perception is a highly conserved process that directs our attention from infancy and is supported by specialized neural circuitry. Oxytocin can increase accuracy and detection of emotional faces, but these effects are mediated by valence, individual differences, and context. We investigated the temporal dynamics of oxytocin’s influence on the neural substrates of face perception using event related potentials (ERP). In a double blind, placebo controlled within-subject design, 21 healthy male adults inhaled oxytocin or placebo and underwent ERP imaging during (...) two face processing tasks. Experiment 1 investigated effects of oxytocin on neural correlates of fearful versus neutral facial expressions, and Experiment 2 manipulated point-of-gaze to neutral faces. In Experiment 1, we found that oxytocin reduced N170 latency to fearful faces. In Experiment 2, N170 latency was decreased when participant gaze was directed to the eyes of neutral faces; however, there were no oxytocin-associated effects in response to different facial features. Findings suggest oxytocin modulates early stages of social perception for socially complex information such as emotional faces relative to neutral. These results are consistent with models suggesting oxytocin impacts the salience of socially informative cues during processing, which leads to downstream effects in behavior. Future work should examine how oxytocin affects neural processes underlying basic components of social behavior (such as, face perception) while varying emotional expression of stimuli or comparing different characteristics of participants (e.g., gender, personality traits). (shrink)

In ‘Why not NIMBY?’, Simon Feldman and Derek Turner mount a compelling case that NIMBY claims are not intrinsically morally unjustified, despite the fact that NIMBY-claimants...

Abstract. Richard Feldman’s Uniqueness Thesis holds that “a body of evidence justifies at most one proposition out of a competing set of proposi- tions”. The opposing position, permissivism, allows distinct rational agents to adopt differing attitudes towards a proposition given the same body of evidence. We assess various motivations that have been offered for Uniqueness, including: concerns about achieving consensus, a strong form of evidentialism, worries about epistemically arbitrary influences on belief, a focus on truth-conduciveness, and consequences for peer (...) disagreement. We argue that each of these motivations either misunderstands the commitments of permissivism or is question-begging. Better understanding permissivism makes it a much more plausible position. (shrink)

Deontological evidentialism is the claim that we ought to form and maintain our beliefs in accordance with our evidence. In this paper, I criticize two arguments in its defense. I begin by discussing Berit Broogard’s use of the distinction between narrow-scope and wide-scope requirements against W.K. Clifford’s moral defense of. I then use this very distinction against a defense of inspired by Stephen Grimm’s more recent claims about the moral source of epistemic normativity. I use this distinction once again to (...) argue that Hilary Kornblith’s criticism of Richard Feldman’s defense of is incomplete. Finally, I argue that Feldman’s defense is insensitive to the relation between normative requirements and privileged values: values that have normative authority over us. (shrink)

What do we mean when we say we "know" something? What is this knowledge and how do we come by it? What exactly counts as an object of knowledge? And on what basis do we defend our claims to know against thosethe skepticswho deny that knowledge is possible or that our criteria for knowing can ever be satisfied? These questions and many others are addressed in this fascinating collection of essays by leading philosophers, who discuss the nature, meaning, and extent (...) of human knowledge. Included are works by Robert Almeder, William P. Alston, Robert P. Amico, Roderick M. Chisholm, Edmund L. Gettier, Richard Feldman, Peter D. Klein, Keith Lehrer, Kenneth G. Lucey, John Pollock, and others. Several essays are original to this collection and break new ground on such issues as the Problem of the Criterion. (shrink)

We affirm the dynamical systems approach taken by Feldman and Levin, but argue that a more mathematically rigorous and standard exposition of the model according to dynamical systems theory would greatly increase readability and testability. Such an explication would also have heuristic value, suggesting new variations of the model. We present one such variant, a new solution to the redundancy problem.

We argue that the concept of a control variable (CV) as described by Feldman and Levin needs to be revised because it does not account for the influence of sensory feedback from the periphery. We provide evidence from the realm of rhythmic movements that sensory feedback can permanently alter the frequency and phase of a centrally generated rhythm.

À partir de l’observatoire d’une « consultation antialcoolique » ouverte en 1954 dans le 13e arrondissement de Paris, cet article étudie la manière dont le travail social a investi le nouveau champ d’action du suivi psychiatrique de l’alcoolisme, dans un contexte de mutations de la prise en charge médicale de cette maladie. Le contenu autant que la structure des dossiers de patients de la consultation, que nous mettons en regard avec des publications issues de revues médicales et de travail social, (...) permettent d’approcher le travail quotidien des assistantes sociales, au plus près des alcooliques et de leurs familles. Nous montrons que l’action de l’assistante sociale, devenue centrale bien que subordonnée à celle du médecin psychiatre, s’enrichit d’une dimension psychothérapique et se caractérise par la recherche de la confiance du malade et de son adhésion au traitement, marquant ainsi une inflexion nette dans le rapport aux populations assistées. Cependant, ces évolutions ne suffisent pas à débarrasser le travail social de ses ambiguïtés constitutives et notamment de ses fonctions de contrôle et de surveillance, sources de difficultés, de malentendus et de conflits avec les malades et leurs proches. (shrink)

The seeming absence of negative evidence in the input that children receive during language acquisition has long been regarded as a serious problem for non-nativist linguistic theories. Among the solutions that have been suggested for this problem, preemption by competing structures is doubtless the most intensively researched and widely accepted. However, while preemption works well in the domain of morphology, it cannot apply categorically in the domain of syntax, as this would preclude the existence of semantically overlapping constructions, such as (...) the ditransitive and the prepositional dative, which can be used alternatively with many, but not all, verbs of literal or metaphorical transfer. This paper investigates one specific version of preemption briefly entertained by Pinker (Language learnability and language development, Harvard University Pressm, 1984), which would account both for the existence of semantically overlapping constructions and for the fact that these constructions may preempt each other in the case of individual verbs. Typically, such pairs of grammatical constructions differ in their information-structural restrictions and speakers tend to choose the construction that best fits a given discourse context; when speakers use a construction even though there is an alternative that fits the discourse context better, children may take this as evidence that the alternative is not available for the specific verb in question. Two corpus studies are presented, comparing the information-structural profile of prepositional dative constructions containing verbs that may alternate between the dative and the ditransitive with the information structural profile of verbs that are restricted to the prepositional dative. For Pinker's preemptive mechanism to be feasible, there should be a clear and systematic difference in the information-structural profile of these two classes of verbs. However, no such difference can be found in actual usage. (shrink)

At the end of the first book of Apollonius' Argonautica, Telamon accuses Jason of plotting to leave Heracles behind, an insult for which Telamon later apologizes. This article suggests that their reconciliation unites the Alexandrian interest in what is appropriate for epic with Aristotelian views on anger and political friendship, two themes that resonate throughout the poem. While Telamon's apology and Jason's moderate response revise the structure of traditional epic quarrels, the portrayal of self-control in this episode constitutes a moral (...) exemplar in keeping with those Homeric scenes that were admired by ancient philosophers. (shrink)