Biomedical subjects

Franz Mechsner

Publications and source records attributed to Franz Mechsner.

5 recordsLinked to original sources

PubMed2006

Target-related coupling in bimanual reaching movements.

While bimanual interference effects can be observed when symbolic cues indicate the parameter values of simultaneous reaching movements, these effects disappear under conditions in which the target locations of two movements are cued directly. The present study investigates the generalizability of these target-location cuing benefits to conditions in which symbolic cues are used to indicate target locations (i.e., the end points of bimanual movements). Participants were asked to move to two of four possible target locations, being located either at the same and different distances (Experiment 1), or in the same and different directions (Experiment 2). Circles and crosses served as symbolic target-location cues and were arranged in a symmetric or non-symmetric fashion over the four target locations. Each trial was preceded by a variable precuing interval. Results revealed faster initiation times for equivalent as compared to non-equivalent target locations (same vs. different cues). Moreover, the time course of prepartion suggests that this effect is in fact due to target-equivalence and not to cue-similarity. Bimanual interference relative to movement parameter values was not observed. These findings suggest that cuing target locations can dominate potential intermanual interference effects during the concurrent programming of different movement parameter values.

Adult↗

PubMed2005

Representation of motor skills in human long-term memory.

This study uses the example of the tennis serve to investigate the nature and role of long-term memory in skilled athletic performance. Information processing linked with complex movements has always been notoriously difficult to investigate. However, a new experimental method revealed that athletic expertise was characterized by well-integrated networks of so-called basic action concepts (BACs) that each corresponded to functionally meaningful submovements. In high-level experts, these representational frameworks were organized in a distinctive hierarchical tree-like structure, were remarkably similar between individuals and were well matched with the functional and biomechanical demands of the task. In comparison, action representations in low-level players and nonplayers were organized less hierarchically, were more variable between persons and were less well matched with functional and biomechanical demands. It is concluded that, in concert with situational goals and constraints, movement representations of this kind in long-term memory might provide the basis for action control in skilled voluntary movements in the form of suitably organized perceptual-cognitive reference structures.

Adult↗

PubMed2004

Making sense.

Explore the source record for details and available documents.

Adult↗

PubMed2004

Do muscles matter for coordinated action?

This article investigates coordination stability when 2 fingers of each hand periodically tap together. The main question concerns the functional origin of the symmetry tendency, which has widely been conceived as a bias toward coactivation of homologous fingers and homologous muscular portions. In Experiment 1, the symmetry tendency was independent of finger combination. In Experiment 2, virtually identical stability characteristics were revealed under full vision and no vision. In Experiment 3, symmetrical and parallel visual labels on the fingers neither stabilized nor destabilized symmetrical and parallel tapping patterns. In Experiment 4, in which the relative position of the hands was varied, it revealed that the observed stability characteristics are to be defined in a hand-centered reference frame. Because the symmetry tendency was always independent of finger combination, the authors suggest that it is not a bias toward coactivation of homologous muscle portions but instead originates on a more abstract, functional level.

Adolescent↗

PubMed2004

A psychological approach to human voluntary movement.

The author argues that movements are planned, executed, and stored in memory as perceptible events, without regard to efferent patterns. Spontaneous bimanual coordination phenomena are hypothesized to originate on a perceptual-cognitive level, with the muscles automatically tuned in service to preferred perceptible movement properties. The perceptual-cognitive system is hypothesized to control skilled complex movements as well. In perceptual-cognitive control, the full potential of the perceptual-cognitive system could be exploited. Thus, movements could be enormously flexible, with a strong potential for improvisation and creativity. An effective representation might be organized in a surprisingly sparse and economic way. In sum, the author argues that a psychological approach is most promising as a possible unifying perspective for understanding human voluntary movements.

Brain↗