Search results for " Imagery"

Does Observation of Postural Imbalance Induce a Postural Reaction?

2011

Import JabRef | WosArea Life Sciences and Biomedicine - Other Topics; International audience; Background: Several studies bring evidence that action observation elicits contagious responses during social interactions. However automatic imitative tendencies are generally inhibited and it remains unclear in which conditions mere action observation triggers motor behaviours. In this study, we addressed the question of contagious postural responses when observing human imbalance. Methodology/Principal Findings: We recorded participants' body sway while they observed a fixation cross (control condition), an upright point-light display of a gymnast balancing on a rope, and the same point-light di…

Discrete and effortful imagined movements do not specifically activate the autonomic nervous system.

2009

International audience; BACKGROUND: The autonomic nervous system (ANS) is activated in parallel with the motor system during cyclical and effortful imagined actions. However, it is not clear whether the ANS is activated during motor imagery of discrete movements and whether this activation is specific to the movement being imagined. Here, we explored these topics by studying the baroreflex control of the cardiovascular system. METHODOLOGY/PRINCIPAL FINDINGS: Arterial pressure and heart rate were recorded in ten subjects who executed or imagined trunk or leg movements against gravity. Trunk and leg movements result in different physiological reactions (orthostatic hypotension phenomenon) whe…

Pupil Diameter May Reflect Motor Control and Learning

2017

International audience; Non–luminance-mediated changes in pupil diameter have been used since the first studies by Darwin in 1872 as indicators of clinical, cognitive, and arousal states. However, the relation between processes involved in motor control and changes in pupil diameter remains largely unknown. Twenty participants attempted to compensate random walks of a cursor with a computer mouse to restrain its trajectory within a target circle while the authors recorded their pupil diameters. Two conditions allowed the authors to experimentally manipulate the motor and cognitive components of the task. First, the step size of the cursor's random walk was either large or small leading to 2…

Comparison of actual and imagined execution of whole-body movements after a long exposure to microgravity

2003

Five cosmonauts were tested 30 days before a six-month space flight and also on the 2nd and the 6th day after their return to Earth. Cosmonauts performed and imagined a task that involved climbing two stairs to step onto a platform, jumping down with both feet and walking normally for a distance of 4 m. Durations of actual and imagined movements were measured by an electronic stopwatch. Results indicated that cosmonauts performed actual and imagined movements with similar durations before and after the space flight. However, the 2nd day after their return to Earth, cosmonauts significantly increased the durations of both actual and imagined movements. The durations of the imagined and actua…

Mentally Simulated Motor Actions in Children

2009

The present study investigated the effects of age and arm preference on motor imagery ability. Children (groups: 6.5, 8.3, and 10.1 years) and young adults (22.4 years) physically or mentally performed a drawing motor task with the right or the left arm. Imagery ability, accessed by the timing correspondence between executed and imagined movements, was poor at 6 and 8 years but improved at age 10, and was robust in adults. The arm condition had no influence on imagery ability. We suggest that maturation of parietal and prefrontal cortices during development may contribute to improvement of action representation.

Corticospinal Modulations during Motor Imagery of Concentric, Eccentric, and Isometric Actions

2019

PURPOSE It is not known yet whether the neurophysiological specificity of eccentric, concentric, and isometric contractions can also be observed when these are mentally simulated. Therefore, our aim was to assess corticospinal excitability during motor imagery (MI) of different contraction types and to test whether a passive movement during MI could have additional effects. METHODS Twelve young participants imagined contractions of the wrist flexors, firstly with the arm motionless (static mode) and second, with a congruent passive movement (wrist extension during eccentric MI and wrist flexion during concentric MI). Motor-evoked potentials (MEP) and H-reflexes were elicited in flexor carpi…

The unnecessary image

2014

Mapping wild pear trees (Pyrus bourgaeana) in Mediterranean forest using high-resolution QuickBird satellite imagery

2012

Recent advances in spatial and spectral resolution of satellite imagery as well as in processing techniques are opening new possibilities of fine-scale vegetation analysis with interesting applications in natural resource management. Here we present the main results of a study carried out in Sierra Morena, Cordoba southern Spain, aimed at assessing the potential of remote-sensing techniques to discriminate and map individual wild pear trees Pyrus bourgaeana in Mediterranean open woodland dominated by Quercus ilex . We used high spatial resolution 2.4 m multispectral/0.6 m panchromatic QuickBird satellite imagery obtained during the summer of 2008. Given the size and features of wild pear tr…

Tra metaforizzazione e simbolizzazione: la metafora come dispositivo linguistico di visualizzazione?

2023

In this paper we will consider metaphor as a phenomenon that lies at the interface between language and imagination. By focusing on how this phenomenon works, we will attempt to shed light on how symbols work. After analyzing the relationship between metaphor and sym bol to highlight the main similarities and differences, we will examine the functions of metaphor with particular reference to the thought of Paul Ricœur. In particular, we will highlight the role that the French thinker attributes to the imagination in constructing the meaning of a metaphor. Finally, after highlighting the relationship between images and words, between the linguistic dimension and the dimension of aisthesis in…

Il triangolo non l'avevo considerato. Metafora, immagini mentali proposizioni tra Relevance Theory e Perceptual Symbol Theory.

2020

In this paper we will show the need for a multimodal approach to the study of metaphorical utterances. We will discuss this hypothesis showing potentials and limits of the metaphor studies conducted within Relevance Theory, which has represented the most authoritative and radical theoretical framework based on the propositional character of metaphorical utterances. In particular, we will focus on the last papers by Carston (2010, 2018), in which it is recognized that the comprehension of complex and poetic metaphors could involve the activation of mental images. We will discuss the problem that the notion of mental imagery poses to Relevance Theory and we will try to overcome these problems…