& The functional equivalence of overt movements and dynamic imagery is of fundamental importance in neuroscience. Here, we investigated the participation of the neocortical motor areas in a classic task of dynamic imagery, Shepard and Metzler's mental rotation task, by time-resolved single-trial functional Magnetic Resonance Imaging (fMRI). The subjects performed the mental-rotation task 16 times, each time with different object pairs. Functional images were acquired for each pair separately, and the onset times and..

Is the assessment of motor milestones valid and scaled equivalently for all infants? It is not only important to understand if the way we use gross and fine motor scores are appropriate for monitoring motor milestones but also to determine if these scores are confounded by specific infant characteristics. Therefore, the aim of the study is to investigate the latent structure underlying motor milestone assessment in infancy and measurement invariance across sex, birth weight, and gestational age. (...) For this study, the birth cohort data from the United Kingdom Millennium Cohort Study was used, which includes the assessment of eight motor milestone tasks from the Denver Developmental Screening Test in 9-month-old infants, depicting early motor development of the first children of generation Z. Confirmatory factor analyses showed a better model fit for a two-factor structure compared to a one-factor structure, and multiple indicators multiple causes modeling revealed no differential item functioning related to sex, birth weight, and gestational age. The study provides support for the use of gross and fine motor scores when assessing motor milestones in infants—both boys and girls with different birth weights and of varying gestational ages. Further investigation into widely adopted assessment tools is recommended to support the use of valid composite scores in early childhood research and practice. (shrink)

First, I note three questions that need further exploration: how fast the emulator operates, compared to the real-time events it models; what exactly perceptual emulation, with no motor component, consists of; and whether images are equivalent to raw sensations. Next, I propose that Grush's framework can explain the role of motor activation in processing “imitable” stimuli.

This paper concerns how motor actions are neurally represented and coded. Action planning and motor preparation can be studied using a specific type of representational activity, motor imagery. A close functional equivalence between motor imagery and motor preparation is suggested by the positive effects of imagining movements on motor learning, the similarity between the neural structures involved, and the similar physiological correlates observed in both imaging and preparing. The content of motor representations (...) can be inferred from motor images at a macroscopic level, based on global aspects of the action and the motor rules and constraints which predict the spatial path and kinematics of movements. A more microscopic neural account calls for a representation of object-oriented action. Object attributes are processed in different neural pathways depending on the kind of task the subject is performing. During object-oriented action, a pragmatic representation is activated in which object affordances are transformed into specific motor schemas. Animal as well as human clinical data implicate the posterior parietal and premotor cortical areas in schema instantiation. A mechanism is proposed that is able to encode the desired goal of the action and is applicable to different levels of representational organization. (shrink)

Learning in intelligent systems is a result of direct or indirect interaction with the environment. Humans can learn by way of different states of (inter-)action such as the execution or the imagery of an action, but their unique potential to induce brain-related as well as mind-related changes in the motor action system is still being debated. The systematic repetition of different states of action (e.g., execution and imagery in terms of physical and mental practice) and their contribution to the (...) learning of complex motor actions has traditionally been approached by way of performance improvements. More recently, approaches highlighting the role of action representation in the learning of complex motor actions have evolved. In the present perspective paper, we build on brain-related findings and sketch recent research on learning by way of imagery and execution from a hierarchical, perceptual-cognitive approach to the motor action system. These findings provide valuable insights into the learning of intelligent systems from a perceptual-cognitive, representation-based perspective and as such add to our current understanding of action representation in memory and its changes with practice. Future research should build bridges between approaches in order to more thoroughly understand functional changes throughout the learning process, and to jointly contribute to developing intelligent cognitive systems and their application in robotics, rehabilitation, or sports. (shrink)

Jeannerod's target article describes support, through empirical and neurological findings, for the intriguing idea of motor imagery, a form of representation hypothesized to have levels of functional equivalence with motor preparation, while being consciously accessible. Jeannerod suggests that the subjectively accessible content of motor imagery allows it to be distinguished from motor preparation, which is unconscious. Motor imagery is distinguished from visual imagery in terms of content. Motor images are kinesthetic in nature; they (...) are parametrized by variables such as force and time and they are potentially governed by kinematic rules. Jeannerod acknowledges, however, that motor and visual imagery may not easily be separated, because actions take place in a spatial environment. I agree; in fact, I suggest here that visualization may generally be concomitant with, and may even subjectively dominate, motor imagery. (shrink)

IntroductionDeep brain stimulation is an effective treatment for advanced Parkinson’s disease with the targeting bilateral subthalamic nucleus or globus pallidus internus. So far, detailed studies on the efficacy of unilateral STN-DBS for motor symptoms have been reported, but few studies have been conducted on unilateral GPi-DBS.Materials and MethodsSeventeen patients with Parkinson’s disease who underwent unilateral GPi-DBS were selected. We conducted comparison analyses between scores obtained 6–42 months pre- and postoperatively using the following measurement tools: the Movement Disorder Society Unified (...) Parkinson’s Disease Rating Scale part III, the Hoehn and Yahr stage, the presence/absence of dyskinesia, Mini-Mental State Examination, Frontal Assessment Battery, Geriatric Depression Scale, levodopa equivalent dose, and cerebral blood flow by single photon emission computed tomography. Patient backgrounds were compared between four cohorts with favorable and unfavorable postoperative outcome.ResultsSignificant improvement was observed postoperatively in the following: total MDS-UPDRS Part III scores during the off period, contralateral scores, ipsilateral scores, and axial scores. Similarly, the Hoehn and Yahr stages during the off period, and GDS also showed significant decrease. In contrast, LED, MMSE, and FAB remained unchanged while the number of patients who scored positive for dyskinesia decreased by 40%. Abnormal cerebral blood flow preoperatively seen in the cerebral cortex had normalized in the total score-based good responder cohort. In the ipsilateral score-based good responder cohort, cerebral blood flow increased in the contralateral frontal lobe including in the premotor cortex, contralateral to the DBS. Compared to the poor responders, postoperative good responders demonstrated significantly higher preoperative MMSE scores.DiscussionUnilateral GPi-DBS therapy was effective in improving contralateral, ipsilateral, and axial motor symptoms of patients with advanced PD; in particular, it was found to be especially beneficial in PwPD whose cognitive function was unimpaired; the treatment efficacy rivaled that of bilateral counterparts up till at least 6 months postoperatively. Finally, normalization of preoperative abnormalities in cerebral blood flow and increased cerebral blood flow in the contralateral frontal lobe indicated the beneficial potential of this therapy on ipsilateral motor symptoms. (shrink)

In order to avoid the motor damage caused by excessive temperature rise of armature winding of the walking motor during braking of high-voltage inspection robot in complexity microgrid networks, an unpowered downhill speed and energy recovery optimization control strategy is proposed based on temperature rise characteristics of the walking motor. Firstly, the thermal equivalent circuit model of the walking motor is established, and the mapping relationship between the armature winding temperature of the walking motor and (...) ambient temperature is solved; secondly, the influence of armature winding temperature on unpowered downhill speed and energy recovery control strategy of robot is analyzed; thirdly, according to the temperature of front and rear wheel walking motors and the temperature difference between them, the optimal control strategy of unpowered downhill speed and energy recovery of robot is put forward; fourthly, by adjusting the duty ratio u of the energy consumption speed control system and the front wheel feedback brake distribution factor λ, the temperature difference between the front and rear wheel walking motors is reduced. Through the experimental analysis on the simulated line, it is verified that the unpowered downhill speed and energy recovery optimization control method based on the temperature rise characteristics of the walking motor can effectively reduce the temperature difference between the front and rear wheels. (shrink)

Ecological and sensorimotor theories of perception build on the notion of action-dependent invariants as the basic structures underlying perceptual capacities. In this paper we contrast the assumptions these theories make on the nature of perceptual information modulated by action. By focusing on the question, how movement specifies perceptual information, we show that ecological and sensorimotor theories endorse substantially different views about the role of action in perception. In particular we argue that ecological invariants are characterized with reference to transformations produced (...) in the sensory array by movement: such invariants are transformation-specific but do not imply motor-specificity. In contrast, sensorimotor theories assume that perceptual invariants are intrinsically tied to specific movements. We show that this difference leads to different empirical predictions and we submit that the distinction between motor equivalence and motor-specificity needs further clarification in order to provide a more constrained account of action/perception relations. (shrink)

Most conceptual models of the organization of the cardiovascular system begin with the premise that the nervous system regulates the metabolic and nonmetabolic reflex adjustments of the circulation. These models assume that all the neurally mediated responses of the circulation are reactive, i.e., reflexes elicited by adequate stimuli. This target article suggests that the responses of the circulation are conditional in three senses. First, as Sherrington argued, reflexes are conditional in that they never operate in a vacuum but in a (...) context together with other reflexes. Guided by functional utility, they interact rather than add. Second, as Pavlov argued, stimuli acquire meanings as a result of experience. This notion of stimulus effect plus the Sherringtonian notion of conditionality suggest that association is one of the ways stimuli eliciting cardiovascular reflexes acquire their meanings and thus their relative strengths. Finally, as Skinner and others have argued, operants are responses that act upon the environment to obtain consequences – that is, stimuli. As operants, cardiovascular responses fulfill a major biological need, functioning proactively. The cardiovascular response is an integral component of the animal's behavior regardless of whether it is an elicited reflex or the eliciting stimulus acquired its properties as a result of the genetic inheritance of the animal or through experience, or the cardiovascular response is emitted in anticipation of an environmental consequence. The main theses of this essay are: (1) behavior is an integrated set of responses and the circulation is one of the response systems comprising behavior; (2) behavior is, in part, determined by its functional significance within a context; (3) the contextual factors operative at the time of the behavior have a major role in determining which of the set of possible responses will determine the final act, that is, which behavior will be the effective response and which other behaviors will be concomitants. (shrink)

Merker's insightful broad review fertilely recasts the mind/brain issue, but the phenomenological appeals require additional considerations of behavioral and neural flexibility. Motor equivalences and perceptual constancies may be cortical contributions to a “robotic” tectal orientation mechanism. Intermediate “third layers” of associative neural networks, each with a few diffusely summing convergence-divergence modules, may be the economical expedient by which evolution has extended the limited unity-in-diversity of sensorimotor coordination to perception, action, thinking, and memory. (Published Online May 1 2007).

Spatial attention and eye-movements are tightly coupled, but the precise nature of this coupling is controversial. The influential but controversial Premotor theory of attention makes four specific predictions about the relationship between motor preparation and spatial attention. Firstly, spatial attention and motor preparation use the same neural substrates. Secondly, spatial attention is functionally equivalent to planning goal directed actions such as eye-movements (i.e. planning an action is both necessary and sufficient for a shift of spatial attention). Thirdly, planning (...) a goal directed action with any effector system is sufficient to trigger a shift of spatial attention. Fourthly, the eye-movement system has a privileged role in orienting visual spatial attention. This article reviews empirical studies that have tested these predictions. Contrary to predictions one and two there is evidence of anatomical and functional dissociations between endogenous spatial attention and motor preparation. However, there is compelling evidence that exogenous attention is reliant on activation of the oculomotor system. With respect to the third prediction, there is correlational evidence that spatial attention is directed to the endpoint of goal-directed actions but no direct evidence that this attention shift is dependent on motor preparation. The few studies to have directly tested the fourth prediction have produced conflicting results, so the extent to which the oculomotor system has a privileged role in spatial attention remains unclear. Overall, the evidence is not consistent with the view that spatial attention is functionally equivalent to motor preparation so the Premotor theory should be rejected, although a limited version of the Premotor theory in which only exogenous attention is dependent on motor preparation may still be tenable. A plausible alternative account is that activity in the motor system contributes to biased competition between different sensory representations with the winner of the competition becoming the attended item. (shrink)

BackgroundReflexive pitch perturbation experiments are commonly used to investigate the neural mechanisms underlying vocal motor control. In these experiments, the fundamental frequency–the acoustic correlate of pitch–of a speech signal is shifted unexpectedly and played back to the speaker via headphones in near real-time. In response to the shift, speakers increase or decrease their fundamental frequency in the direction opposing the shift so that their perceived pitch is closer to what they intended. The goal of the current work is to (...) develop a quantitative model of responses to reflexive perturbations that can be interpreted in terms of the physiological mechanisms underlying the response and that captures both group-mean data and individual subject responses.MethodsA model framework was established that allowed the specification of several models based on Proportional-Integral-Derivative and State-Space/Directions Into Velocities of Articulators (DIVA) model classes. The performance of 19 models was compared in fitting experimental data from two published studies. The models were evaluated in terms of their ability to capture both population-level responses and individual differences in sensorimotor control processes.ResultsA three-parameter DIVA model performed best when fitting group-mean data from both studies; this model is equivalent to a single-rate state-space model and a first-order low pass filter model. The same model also provided stable estimates of parameters across samples from individual subject data and performed among the best models to differentiate between subjects. The three parameters correspond to gains in the auditory feedback controller’s response to a perceived error, the delay of this response, and the gain of the somatosensory feedback controller’s “resistance” to this correction. Excellent fits were also obtained from a four-parameter model with an additional auditory velocity error term; this model was better able to capture multi-component reflexive responses seen in some individual subjects.ConclusionOur results demonstrate the stereotyped nature of an individual’s responses to pitch perturbations. Further, we identified a model that captures population responses to pitch perturbations and characterizes individual differences in a stable manner with parameters that relate to underlying motor control capabilities. Future work will evaluate the model in characterizing responses from individuals with communication disorders. (shrink)

Background: The new human coronavirus that leads to COVID-19 has spread rapidly around the world and has a high degree of lethality. In more severe cases, patients remain hospitalized for several days under treatment of the health team. Thus, it is important to develop and use technologies with the aim to strengthen conventional therapy by encouraging movement, physical activity, and improving cardiorespiratory fitness for patients. In this sense, therapies for exposure to virtual reality are promising and have been shown to (...) be an adequate and equivalent alternative to conventional exercise programs.Aim: This is a study protocol with the aim of comparing the conventional physical therapy intervention with the use of a non-immersive VR software during COVID-19 hospitalization.Methods: Fifty patients hospitalized with confirmed diagnosis of COVID-19 will be divided in two groups under physiotherapy treatment using conventional or VR intervention: Group A: participants with COVID-19 will start the first day of the protocol with VR tasks in the morning and then in the second period, in the afternoon, will perform the conventional exercises and Group B: participants with COVID-19 will start the first day with conventional exercises in the morning and in the second period, in the afternoon, will perform activity with VR. All participants will be evaluated with different motor and physiologic scales before and after the treatment to measure improvements.Conclusion: Considering the importance of benefits from physical activity during hospitalization, VR software shows promise as a potential mechanism for improving physical activity. The results of this study may provide new insights into hospital rehabilitation.Trial Registration:ClinicalTrials.gov, identifier: NCT04537858. Registered on 01 September 2020. (shrink)

I argue that the Aristotelian definition of motion,“the act of what exists potentially insofar as it exists potentially,” and the mover causality principle,“whatever is moved is moved by another,” are compatible with Newton’s First Law of Motion, which treats inertialmotion as a state equivalent to rest and which requires no sustaining mover for such motion. Both traditions treat motion as such as requiring an initial, generating mover but not necessarily a sustaining motor. Through examining examples of motion as treated (...) by Newtonian physics, and through arguing that potential energy is Aristotelian potentiality, I argue that the First Law is understandable according to the Aristotelian definition as an incomplete act with a twofold ordination of the same potentiality. I then propose that, through the notion of spacetime, Special and General Relativity instantiate motion as a unity of differentiated prior and posterior parts that do not coexist in reality. (shrink)

Negative compatibility effects in the masked-prime paradigm are usually obtained when primes are masked effectively. With ineffective masks—and primes above the perceptual threshold—positive compatibility effects occur. We investigated whether this pattern reflects a causal relationship between conscious awareness and low-level motor control, or whether it reflects the fact that both are affected in the same way by changes in physical stimulus attributes. In a 5-session perceptual learning task, participants learned to consciously identify masked primes. However, they showed unaltered NCEs (...) that were not different from those produced by participants in a control group without equivalent perceptual learning. A control experiment demonstrated that no NCEs occur when prime identification is made possible by ineffective masking. The results suggest that perceptual awareness and low-level motor control are affected by the same factors, but are fundamentally independent of each other. (shrink)

Playing with correct intonation is one of the major challenges for a string player. A player must learn how to physically reproduce a target pitch, but before that, the player must learn what correct intonation is. This requires audiation- the aural equivalent of visualization- of every note along with self-assessment whether the pitch played matches the target, and if not, what action should be taken to correct it. A challenge for successful learning is that much of it occurs during practice, (...) typically without outside supervision. A student who has not yet learned to hear correct intonation may repeatedly practice out of tune, blithely normalising bad habits and bad intonation. The real-time reflective nature of intonation and its consistent demand on attention make it a ripe target for technological intervention. Using a violin augmented to combine fingerboard sensors with audio analysis for real-time pitch detection, we examine the efficacy of three methods of real-time feedback for improving intonation and pitch learning. The first, aural feedback in the form of an in-tune guide pitch following the student in real-time, is inspired by the tradition of students playing along with teachers. The second is visual feedback on intonation correctness using an algorithm optimised for use throughout normal practice. The third is a combination of the two methods, simultaneously providing aural and visual feedback. Twelve beginning violinists, including children and adults, were given four in-situ 20-30 minute lessons. Each lesson used one of the intonation feedback methods, along with a control lesson using no feedback. We collected data on intonation accuracy and conducted interviews on student experience and preference. The results varied by player, with evidence of some players being helped by the feedback methods but also cases where the feedback was distracting and intonation suffered. However interviews suggested a high level of interest and potential in having such tools to help during practice, and results also suggested that it takes time to learn to use the real-time aural and visual feedback. Both methods of feedback demonstrate potential for assisting self-reflection during individual practice. (shrink)

Natural language meaning has properties of both (embodied) cognitive representations and formal/mathematical structures. But it is not clear how they actually relate to one another. This article argues that how properties of cognitive representations and formal/mathematical structures of natural language meaning can be united remains one of the puzzles in cognitive science. That is primarily because formal/mathematical structures of natural language meaning are abstract, logical, and truth‐conditional properties, whereas cognitive/conceptual representations are embodied and grounded in sensory‐motor systems. After reviewing (...) the current progress, this work offers, in outline, the general formulations that show how these two different kinds of representations for semantic structures can (potentially) be unified and also proposes three desiderata for testing, in brain dynamics, the mathematical equivalence between formal symbolic representations (and their transitions), and neuronal population codes (and their transitions). (shrink)

Based on evidence that learning new characters through handwriting leads to better recognition than learning through typing, some authors proposed that the graphic motor plans acquired through handwriting contribute to recognition. More recently two alternative explanations have been put forward. First, the advantage of handwriting could be due to the perceptual variability that it provides during learning. Second, a recent study suggests that detailed visual analysis might be the source of the advantage of handwriting over typing. Indeed, in that (...) study, handwriting and composition –a method requiring a detailed visual analysis but no specific graphomotor activity– led to equivalent recognition accuracy, both higher than typing. The aim of the present study was to assess whether the contribution of detailed visual analysis is observed in preschool children and to test the variability hypothesis. To that purpose, three groups of preschool children learned new symbols either by handwriting, typing, or composition. After learning, children performed first a four-alternative recognition task and then a categorization task. The same pattern of results as the one observed in adults emerged in the four-alternative recognition task, confirming the importance of the detailed visual analysis in letter-like shape learning. In addition, results failed to reveal any difference across learning methods in the categorization task. The latter results provide no evidence for the variability hypothesis which would predict better categorization after handwriting than after typing or composition. (shrink)

In keeping with recent views of consciousness of self as represented in the body in action, empirical studies are reviewed that demonstrate a bottlenose dolphin’s conscious awareness of its own body and body parts, implying a representational “body image” system. Additional work reviewed demonstrates an advanced capability of dolphins for motor imitation of self-produced behaviors and of behaviors of others, including imitation of human actions, supporting hypotheses that dolphins have a sense of agency and ownership of their actions and (...) may implicitly attribute those levels of self-awareness to others. Possibly, a mirror-neuron system, or its functional equivalent to that described in monkeys and humans, may mediate both self-awareness and awareness of others. (shrink)

I consider how we might begin to redress a cognitive model for thought experimental and other imagery-based scientific reasoning from an embodied cognition viewpoint. The paper gravitates on clarifying tour issues: (i) the danger of understanding the genuine novelty of thought-experimental reasoning and other imagery-based reasoning as a product of ‘quasi-perceiving’ new phenomenology with the ‘mind’s eye’ (as asserted by quasi-pictorialist theories of imagery); (ii) the erroneous choice of units of analysis that assume equivalence of external reports of visual (...) imagery with those internal structures that govern imagery-based reasoning, which are, as I will argue, largely linked to motor processes; (iii) the establishment of thought experimentation as imagery-based reasoning by providing evidence for the psychological necessity of imagistic simulation in thought experiments; (iv) a cognitive model for how learning via thought experimentation and other imagery-based reasoning takes place. The study was underpinned by constructivist assumptions. Case methodology was adopted, the case being a pair of final year A-level physics students. Data was collected through non-participant observation over two sessions of collaborative problem-solving. The tasks drew upon Newtonian mechanics. (shrink)

Riassunto: Le immagini mentali sono parte delle intenzioni comunicative veicolate negli scambi verbali, e dunque del significato inteso dal parlante? Questioni simili sono state dibattute con riferimento al paradigma dell’ embodiment. Qui intendiamo muoverci su un terreno differente: il dominio dei gesti, con particolare riferimento a quelli rappresentativi, caratterizzati dallo stretto rapporto con le rappresentazioni senso-motorie delle azioni. La linea argomentativa sarà dunque bipartita. Innanzitutto, intendiamo mostrare che i gesti contribuiscono a determinare l’intenzione comunicativa, come è evidente in casi nei (...) quali il parlante si impegna in modo manifesto a renderli salienti – ma qui sarà anche importante l’osservazione che l’intenzione comunicativa non va identificata con una preliminare pianificazione cosciente. In secondo luogo, argomenteremo che il contributo dei gesti all’intenzione comunicativa è genuinamente imagistic, non proposizionale. In particolare, esamineremo due argomenti solitamente presentati come a favore dell’ipotesi proposizionale: che le immagini non possono essere parte dell’intenzione comunicativa, rispettivamente, perché non portano un contenuto giudicabile in termini di vero/falso, e perché non consentono di effettuare inferenze. Vedremo che entrambe le argomentazioni sono discutibili. Parole chiave: Intenzione comunicativa; Gesti rappresentativi; Imagery; Significato del parlante Co-verbal Gestures and Mental Images: The Borders of Communicative Intentions: Do mental images form part of a speaker’s communicative intention? This and similar questions have usually been addressed within the framework of embodied cognition. Here, instead, we want to address the question from a different point of view, examining representational gestures, which are characterised by their strong relationship to sensory-motor representations. For this reason, our argument takes two directions. First, we show that representational gestures can form part of a speaker’s communicative intention as, for example, when the speaker overtly makes them salient. However, it is important to point out that being part of a communicative intention is not equivalent to being consciously planned. Secondly, we will argue that the meaning carried by gestures is actually imagistic, and not propositional. To this end, we provide a detailed discussion of two arguments favouring the propositional hypothesis: that images cannot be part of the speaker’s communicative intention because their content is not truth-conditional and because they do not allow us to make inferences. We will show that both these arguments are debatable. Keywords: Communicative Intentions; Representational Gestures; Imagery; Speaker’s Meaning. (shrink)

Dreyfus enlists the aid of Merleau-Ponty in his critique of representationalist theories of cognition. Such theories posit a representational element at some level of cognitive activity. The nature of the representation and how we think of it will depend upon the level at which one claims to find it. If we consider the case of perception, at one extreme it might be claimed that the representation is a conscious one, that is, that the perceiving subject is conscious of a representation, (...) a _Vorstellung_ in the Kantian sense. In this case, it would clearly come between the perceiving subject and the world and in that sense interfere with a direct perception of the world. This sort of representational theory would be equivalent to idealism, and for good phenomenological reasons it is rejected by Merleau-Ponty and Dreyfus. At the other extreme, it is possible to find cognitive scientists talking about representations at the level of brain activity. Neural representations, either firing patterns or the actual "hard wiring" of neuronal connections (as, for example, neural maps in the somatosensory and motor areas responsible for the experience of the subject's own body), in some way enable perception. At this level of description there are various debates about how these mechanisms can be called representational. If the concept of representation involves reference to the perceptual field, in what sense does a neuronal pattern refer? There are also the familiar debates about how such mechanisms actually function, as well as the difficult problem of how such functions actually translate into personal level experience. Before these debates get off the ground, however, Dreyfus wants to steal the ammunition. He denies that there are representations at the level of brain processes. (shrink)

Bu çalışma İstanbul’da faaliyette bulunan motor-kuryelerin çalışma koşulları, ücret düzeyleri, yasal hakları, iş kazası ve meslek hastalıkları ve karşılaşılan ayrımcılıkların araştırılması amaçlanmıştır. Bu amaçla, 20 motor-kurye ile yarı yapılandırılmış mülakat tekniğiyle görüşmeler gerçekleştirilmiştir. Yapılan görüşmeler sonucunda, motor-kuryelik mesleğinde esnaf ve bordrolu olmak üzere ikili bir yapı oluştuğu; katılımcıların %68’i esnaf, %37’si ise bordrolu olarak çalıştığı görülmektedir. Bordrolu çalışan motor-kuryelerin ücretli izin hakkı bulunurken; esnaf kuryelerin tamamının ücretli izin haklarının olmadığı, %61’ inin ise sosyal güvenceye sahip olmadığı (...) tespit edilmiştir. Katılımcıların %69’u haftada 6 gün çalışırken, %31’i haftada 7 gün çalışmaktadır. Katılımcıların %16’ısı haftalık 45-66 saat arası, %84’ü 67 saat ve üstü çalışmaktadır. Motor-kuryelikte ücretin belirlenmesinde kıdem ya da niteliğin etkili olmadığı, dağıtılan paket sayısının ücreti belirlediği tespit edilmiştir. Bordrolu çalışanların 8.500 TL ile 12.750 TL aralığında ücret kazandıkları, esnaf kurye modelinde ise çoğunluğun 12.750 TL ile 17.000 TL aralığında ücret kazandıkları Esnaf kuryelerin bordrolu kuryelere göre daha fazla gelir elde ettiği görülse de bunun hem daha fazla çalışmadan hem de sigorta primlerinin ödenmemesinden kaynaklandığı sonucuna ulaşılmıştır. Hızlı ve sıcak teslimata ilişkin reklamların kuryelik mesleğinin insani yönünü ortadan kaldırdığı ve kuryelerde dışlanma hissi oluşturduğu tespit edilmiştir. Son olarak, motor-kuryelerin; trafikte, teslimat sırasında ya da sitelerde en az bir kere ayrımcılığa maruz kaldıklarını belirtmektedir. (shrink)

I discuss the relationship between different versions of the equivalence principle in general relativity, among them Einstein's equivalence principle, the weak equivalence principle, and the strong equivalence principle. I show that Einstein's version of the equivalence principle is intimately linked to his idea that in GR gravity and inertia are unified to a single field, quite like the electric and magnetic field had been unified in special relativistic electrodynamics. At the same time, what is now (...) often called the strong equivalence principle, related to the local validity of special relativity, can also be found in Einstein's writings, albeit by a different name and clearly separated from what he calls the equivalence principle. I discuss both the development of Einstein's thoughts on the different versions of the equivalence principle, their relationship to the relativity principle, as well as later reflections and variants proposed. (shrink)

Using a new method, we examined whether incidental perception of need-rewarding (positive) objects unintentionally prepares motor action. Participants who varied in their level of need for water were presented with glasses of water (and control objects) that were accompanied by go and no-go cues that required a response (key-press) or withholding a response. Importantly, if need-rewarding objects unintentionally prepare action, presentation of no-go cues should lead to motor inhibition of these prepared motor impulses. Consistent with this hypothesis, (...) results showed that participants relatively high in need for water (and hence, who perceive water as a rewarding, positive object) were slower to react to a successive action probe after withholding a response during perception of water than during perception of the control object, suggesting motor inhibition of unintentionally prepared motor impulses. We propose that incidental perception of need-rewarding objects unintentionally potentiates preparation of motor action to these objects. (shrink)

To explain why, in scientific problem solving, a diagram can be “worth ten thousand words,” Jill Larkin and Herbert Simon (1987) relied on a computer model: two representations can be “informationally” equivalent but differ “computationally,” just as the same data can be encoded in a computer in multiple ways, more or less suited to different kinds of processing. The roots of this proposal lay in cognitive psychology, more precisely in the “imagery debate” of the 1970s on whether there are image-like (...) mental representations. Simon (1972, 1978) hoped to solve this debate by thoroughly reducing the differences between forms of mental representations (e.g., between images and sentences) to differences in computational efficiency; to carry out this reduction, he borrowed from computer science the concepts of data type and of data structure. I argue that, in the end, his account amounted to nothing more than characterizing representations by the fast operations on them. This analysis then allows me to assess what Simon’s approach actually achieves when transported from psychology to the study of scientific representations, as in Larkin and Simon (1987): it allows comparing, not representations in and of themselves, but rather the computational roles they play in particular problem-solving processes—that is, representations together with a particular way of using them. (shrink)

What are the most detailed descriptions under which subjects intend to perform bodily actions? According to Pacherie (2006), these descriptions may be found by looking into motor representations—action representations in the brain that determine the movements to be performed. Specifically, for any motor representation guiding an action, its subject has an M‐intention representing that action in as much detail. I show that some M‐intentions breach the constraints that intentions should meet. I then identify a set of intentions—motor (...) intentions—that represent actions in as much detail as some motor representations while meeting the constraints that intentions should meet. (shrink)

Abstract Theories are metaphysically equivalent just if there is no fact of the matter that could render one theory true and the other false. In this paper I argue that if we are judiciously to resolve disputes about whether theories are equivalent or not, we need to develop testable criteria that will give us epistemic access to the obtaining of the relation of metaphysical equivalence holding between those theories. I develop such ?diagnostic? criteria. I argue that correctly inter-translatable theories (...) are metaphysically equivalent, and what we need are ways of determining whether a putative translation is correct or not. To that end I develop a number of tools we can employ to discern whether a translation is a correct one. (shrink)

Our ability to acknowledge and recognise our own identity - our 'self' - is a characteristic doubtless unique to humans. Where does this feeling come from? How does the combination of neurophysiological processes coupled with our interaction with the outside world construct this coherent identity? We know that our social interactions contribute via the eyes, ears etc. However, our self is not only influenced by our senses. It is also influenced by the actions we perform and those we see others (...) perform. Our brain anticipates the effects of our own actions and simulates the actions of others. In this way, we become able to understand ourselves and to understand the actions and emotions of others. -/- This book is the first to describe the new field of 'Motor Cognition' - one to which the author's contribution has been seminal. Though motor actions have long been studied by neuroscientists and physiologists, it is only recently that scientists have considered the role of actions in building the self. How consciousness of action is part of self-consciousness, how one's own actions determine the sense of being an agent, how actions performed by others impact on ourselves for understanding others, differentiating ourselves from them and learning from them: these questions are raised and discussed throughout the book, drawing on experimental, clinical, and theoretical bases. -/- The advent of new neuroscience techniques, like neuroimaging and direct electrical brain stimulation, together with a renewal of behavioral methods in cognitive psychology, provide new insights into this area. Mental imagery of action, self-recognition, consciousness of actions, imitation can be objectively studied using these new tools. The results of these investigations shed light on clinical disorders in neurology, psychiatry and in neuro-development. -/- This is a major new work that will lay down the foundations for the field of motor cognition. (shrink)

I argue that Merleau-Ponty’s use of the case of Schneider in his arguments for the existence of non-conconceptual and non-representational motor intentionality contains a problematic methodological ambiguity. Motor intentionality is both to be revealed by its perspicuous preservation and by its contrastive impairment in one and the same case. To resolve the resulting contradiction I suggest we emphasize the second of Merleau-Ponty’s two lines of argument. I argue that this interpretation is the one in best accordance both with (...) Merleau-Ponty’s general methodology and with the empirical case of Schneider as it was described by Gelb and Goldstein. (shrink)

Maurice Merleau-Ponty is often interpreted as claiming that opportunities for action are directly present in perceptual experience. However, he does not provide much evidence for how or why this would occur, and one can doubt that this is an appropriate interpretation of his phenomenological descriptions. In particular, it could be argued the Merleau-Pontyian descriptions mistakenly attribute pre-perceptual or post-perceptual elements such as allocation of attention or judgment to the perceptual experience itself. This paper argues for the Merleau-Pontyian idea that opportunities (...) for action are present in perceptual experience. It further argues that the phenomenological descriptions can be supported and explained via reference to contemporary research on motor imagery. In particular, it will be argued that non-conscious, covert motor imagery is used to prepare for and regulate skilled actions, and that it is plausible that this imagery combines with perception (likely vision) to create a single experience of the environment as enabling action. The paper will also show that contemporary views on motor imagery are broadly compatible with Merleau-Ponty’s aims. (shrink)

What triggers the execution of actions? What happens in that moment when an action is triggered? What mental state is there at the moment of action-execution that was not there a second before? My aim is to highlight the importance of a thus far largely ignored kind of mental state in the discussion of these old and much-debated questions: motor imagery. While there have been a fair amount of research in psychology and neuroscience on motor imagery in the (...) last 30 years or so, it is only recently that we start to understand the important role motor imagery plays in action initiation. And if, as these findings suggest, motor imagery plays an important role in action initiation, we can make progress not only in understanding action initiation in general but also in understanding what goes wrong in akratic actions and in relapse actions. Finally, this new picture of action-initiation also has far-reaching consequences for the relation between motivation and causation in naturalistic action-explanations. (shrink)

The control of action has traditionally been described as "automatic". In particular, movement control may occur without conscious awareness, in contrast to normal visual perception. Studies on rapid visuomotor adjustment of reaching movements following a target shift have played a large part in introducing such distinctions. We suggest that previous studies of the relation between motor performance and perceptual awareness have confounded two separate dissociations. These are: (a) the distinction between motoric and perceptual representations, and (b) an orthogonal distinction (...) between conscious and unconscious processes. To articulate these differences more clearly, we propose a new measure of motor awareness, based on subjects' ability to reproduce the spatial details of reaching movements they have just made. Here we focus on the dissociation between motor awareness and perceptual awareness that may occur when subjects make rapid visuomotor adjustments to reaching movements following a target shift. In experiment 1, motor awareness was dissociated from perceptual awareness of a target shift during reaching movement. Participants' reproduction of movement endpoints following visuomotor adjustment was independent of whether they saw the target shift or not. Experiment 2 replicated this result, and further showed that neither motor awareness nor motor performance were disrupted by TMS over the parietal cortex. The neural mechanisms underlying motor awareness, and the implications for theories of consciousness, are discussed. (shrink)

Much indirect evidence supports the hypothesis that transformations of mental images are at least in part guided by motor processes, even in the case of images of abstract objects rather than of body parts. For example, rotation may be guided by processes that also prime one to see results of a specific motor action. We directly test the hypothesis by means of a dual-task paradigm in which subjects perform the Cooper-Shepard mental rotation task while executing an unseen (...) class='Hi'>motor rotation in a given direction and at a previously learned speed. Four results support the inference that mental rotation relies on motor processes. First, motor rotation that is compatible with mental rotation results in faster times and fewer errors in the imagery task than when the two rotations are incompatible. Second, the angle through which subjects rotate their mental images, and the angle through which they rotate a joystick handle are correlated, but only if the directions of the two rotations are compatible. Third, motor rotation modifies the classical inverted V-shaped mental rotation response time function, favoring the direction of the motor rotation; indeed, in some cases motor rotation even shifts the location of the minimum of this curve in the direction of the motor rotation. Fourth, the preceding effect is sensitive not only to the direction of the motor rotation, but also to the motor speed. A change in the speed of motor rotation can correspondingly slow down or speed up the mental rotation. (shrink)

There is a long‐standing project in psychology the goal of which is to explain our ability to perceive speech. The project is motivated by evidence that seems to indicate that the cognitive processing to which speech sounds are subjected is somehow different from the normal processing employed in hearing. The Motor Theory of speech perception was proposed in the 1960s as an attempt to explain this specialness. The first part of this essay is concerned with the Motor Theory's (...) explanandum. It shows that it is rather hard to give a precise account of what the Motor Theory is a theory of. The second part of the essay identifies problems with the theory's explanans: There are difficulties in finding a plausible account of what the content of the Motor Theory is supposed to be. (shrink)

The comparator-model, originally developed to explain motor action, has recently been invoked to explain several aspects of the self. However, in the first place it may not be used to explain a basic self-world distinction because it presupposes one. Our alternative account is based on specific systematic covariation between action and perception. Secondly, the comparator model cannot explain the feeling of ownership of thoughts. We argue—contra Frith and Campbell—that thoughts are not motor processes and therefore cannot be described (...) by the comparator-model. Rather, thoughts can be the triggering cause (intention) for actions. An alternative framework for the explanation of thought insertion in schizophrenics is presented. (shrink)

Merleau-Ponty’s explication of concrete or practical movement by way of the Schneider case could be read as ending up close to automatism, neglecting its flexibility and plasticity in the face of obstacles. It can be contended that he already goes off course in his explication of Schneider’s condition. Rasmus Jensen has argued that he assimilates a normal person’s motor intentionality to the patient’s, thereby generating a vacuity problem. I argue that Schneider’s difficulties with certain movements point to a means (...) of broadening Merleau-Ponty’s account of concrete movement, one that he broaches without exploiting. What could do more work is his recognition of a transposition capacity - and hence of a plasticity - in the healthy body’s skill schema. As well as avoiding vacuity, he could forestall the appearance of a dichotomy between practical coping and creativity. (shrink)