Showing papers on "Motor imagery published in 1994"

The representing brain: Neural correlates of motor intention and imagery

Abstract: 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 (the duration and amount of effort involved) 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 (independently of other tasks such as object recognition). 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.

Mapping motor representations with positron emission tomography

Abstract: Brain activity was mapped in normal subjects during passive observation of the movements of an 'alien' hand and while imagining grasping objects with their own hand. None of the tasks required actual movement. Shifting from one mental task to the other greatly changed the pattern of brain activation. During observation of hand movements, activation was mainly found in visual cortical areas, but also in subcortical areas involved in motor behaviour, such as the basal ganglia and the cerebellum. During motor imagery, cortical and subcortical areas related to motor preparation and programming were strongly activated. These data support the notion that motor learning during observation of movements and mental practice involves rehearsal of neural pathways related to cognitive stages of motor control.

The learning of motor skills: sports science and ergonomics perspectives

Abstract: The paper describes some of the common origins of ergonomics and sports science in the UK with particular reference to research on motor learning. Attention is drawn to the value of analytical methods developed by ergonomists in deriving training prescriptions and their relationship with conventional learning theory is discussed. The cognitive revolution, which in the last 25 years has changed the face of psychology, has also had its impact on ergonomics and basic research on motor skills. The role of cognitive processes in motor learning is being reassessed and there is a renewed interest in topics such as verbal instruction, imitation, imagery, and mental practice which to earlier generations of behavioural scientists appeared beyond the scope of scientific investigation. The paper outlines some recent research into the role of imagery in motor learning illustrating these new approaches.

Controllability of motor imagery and transformation of visual imagery

Abstract: This study examined the relation between control of motor imagery and generation and transformation of visual imagery by testing 54 subjects. We used two measures of the Controllability of Motor Imagery test to evaluate the ability to control motor imagery. One was a recognition test on which the subject imagines as if one sees another's movement, and the other was a regeneration test on which one imagines as if one moves one's own body. The former test score was related to processing time of a mental rotation task and the latter one was not but would reflect sport experience. It was concluded that two meanings of the test could reflect different aspects such as observational motor imagery and body-centered motor imagery.

On the relation between motor imagery and visual imagery

Abstract: 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.