Université de Fribourg

Cutaneous mechanisms of isometric ankle force control

Choi, Julia T. ; Lundbye-Jensen, Jesper ; Leukel, Christian ; Nielsen, Jens Bo

In: Experimental Brain Research, 2013, p. 1–8

The sense of force is critical in the control of movement and posture. Multiple factors influence our perception of exerted force, including inputs from cutaneous afferents, muscle afferents and central commands. Here, we studied the influence of cutaneous feedback on the control of ankle force output. We used repetitive electrical stimulation of the superficial peroneal (foot dorsum) and medial...

Université de Fribourg

Cross-limb interference during motor learning

Lauber, Benedikt ; Lundbye-Jensen, Jesper ; Keller, Martin ; Gollhofer, Albert ; Taube, Wolfgang ; Leukel, Christian

In: PLoS ONE, 2013, vol. 8, no. 12, p. e81038

It is well known that following skill learning, improvements in motor performance may transfer to the untrained contralateral limb. It is also well known that retention of a newly learned task A can be degraded when learning a competing task B that takes place directly after learning A. Here we investigate if this interference effect can also be observed in the limb contralateral to the trained...

Université de Fribourg

Changes in corticospinal transmission following 8 weeks of ankle joint immobilization

Leukel, Christian ; Taube, Wolfgang ; Rittweger, Jörn ; Gollhofer, Albert ; Ducos, Michel ; Weber, Tobias ; Lundbye-Jensen, Jesper

In: Clinical Neurophysiology, 2015, vol. 126, no. 1, p. 131–139

Joint immobilization has previously been shown to modulate corticospinal excitability. The present study investigated changes in the excitability of distinct fractions of the corticospinal pathway by means of conditioning the H-reflex with transcranial magnetic stimulation (TMS) of the primary motor cortex (Hcond). This method allows assessment of transmission in fast (monosynaptic) and slow(er)...

Université de Fribourg

Short-term pressure induced suppression of the short latency response - a new methodology for investigating stretch reflexes

Leukel, Christian ; Lundbye-Jensen, Jesper ; Gruber, Markus ; Zuur, Abraham T. ; Gollhofer, Albert ; Taube, Wolfgang

In: Journal of Applied Physiology, 2009///doi:10.1152/japplphysiol.00301.2009

During experiments involving ischemic nerve block we noticed that the short latency response (SLR) of evoked stretches in m. soleus decreased immediately following inflation of a pneumatic cuff surrounding the lower leg. The present study aimed to investigate this short-term effect of pressure application in more detail. 58 healthy subjects were divided into 7 protocols. Unilateral stretches were...

Université de Fribourg

Subconscious visual cues during movement execution allow correct online choice reactions

Leukel, Christian ; Lundbye-Jensen, Jesper ; Christensen, Mark Schram ; Gollhofer, Albert ; Nielsen, Jens Bo ; Taube, Wolfgang

In: PLoS ONE, 2012, vol. 7, no. 9, p. e44496

Part of the sensory information is processed by our central nervous system without conscious perception. Subconscious processing has been shown to be capable of triggering motor reactions. In the present study, we asked the question whether visual information, which is not consciously perceived, could influence decision-making in a choice reaction task. Ten healthy subjects (28±5 years) executed...

Université de Fribourg

Surround inhibition in the primary motor cortex is task-specifically modulated in non-professional musicians but not in healthy controls during real piano playing

Márquez, Gonzalo ; Keller, Martin ; Lundbye-Jensen, Jesper ; Taube, Wolfgang

In: Neuroscience, 2018, vol. 373, p. 106–112

Research has indicated that at the onset of a finger movement, unwanted contractions of adjacent muscles are prevented by inhibiting the cortical areas representing these muscles. This so-called surround inhibition (SI) seems relevant for the performance of selective finger movements but may not be necessary for tasks involving functional coupling between different finger muscles. Therefore,...

Université de Fribourg

Repetitive activation of the corticospinal pathway by means of rTMS may reduce the efficiency of corticomotoneuronal synapses

Taube, Wolfgang ; Leukel, Christian ; Nielsen, Jens Bo ; Lundbye-Jensen, Jesper

In: Cerebral Cortex, 2014, p. -

Low-frequency rTMS applied to the primary motor cortex (M1) may produce depression of motor-evoked potentials (MEPs). This depression is commonly assumed to reflect changes in cortical circuits. However, little is known about rTMS-induced effects on subcortical circuits. Therefore, the present study aimed to clarify whether rTMS influences corticospinal transmission by altering the efficiency of...

Université de Fribourg

Evidence that the cortical motor command for the initiation of dynamic plantarflexion consists of excitation followed by inhibition

Taube, Wolfgang ; Lundbye-Jensen, Jesper ; Schubert, Martin ; Gollhofer, Albert ; Leukel, Christian

In: PLoS ONE, 2011, vol. 6, no. 10, p. e25657

At the onset of dynamic movements excitation of the motor cortex (M1) is spatially restricted to areas representing the involved muscles whereas adjacent areas are inhibited. The current study elucidates whether the cortical motor command for dynamic contractions is also restricted to a certain population of cortical neurons responsible for the fast corticospinal projections. Therefore,...