From 1995 to 2000, he was employed as a Hallas Møller Research Fellow at Department of Physiology, University of Copenhagen, and in 1997 he became associate professor at the same place, a position that he held until he was recruited to Karolinska Institute in Sweden in 2001.

In his initial work he showed that vertebrate motor neurons can express transmitter-modulated plateau potentials.

[7] His continued work has shown an involvement of plateaux in disturbed motor symptoms seen after spinal cord injury.

[8] Using molecular mouse genetic, electrophysiology and behavioral studies he has revealed the key cellular organization of spinal locomotor networks and was able to functionally discover and link specific neuronal populations in the spinal cord to the ability to produce the alternating movements between limbs during locomotion[9][10][11][12] and to set the rhythm of locomotion.

[13][15][16] These studies unravel the communication pathway between the brain and the spinal cord needed to control the expression of locomotion.