In total ≈640 papers (including book chapters, commentaries, reviews etc), concerning monoamine neurons, development, growth factors, regeneration, aging, transplantation in the central nervous system, models for Parkinson's disease and its treatment, models for spinal cord injury and treatment strategies, the roles of tran- scription factors in the nervous system, genetic risk factors for Parkinson's disease, the Nogo signaling system, structural synaptic plasticity and the formation of lasting memories. H-index 99. Since 2000 original member of "Highly Cited Reseachers Database", ISI. Research has been taken all the way from animal studies to clinical trials. We published the first evidence that transplantation of embryonic dopamine neurons can counteract Parkinson's disease in an animal model (Perlow et al Science 1979), the first transplantation trials in patients with Parkinson's disease (Backlund et al J Neurosurg 1985) and the first delivery of NGF to the human brain (Olson et al Arch Neurol 1991). Independent discovery of the NGF-family member NT3 (Ernfors et al PNAS 1990). We demonstrated protection and repair of the dopamine system by GDNF (Tomac et al Nature 1995). First demonstration of functional effects of a repair strategy for complete spinal cord injury in an adult mammal (Cheng et al Science 1996). We discovered dopamine neuron agenesis in Nurr1-deficient mice (Zetterström et al Science 1997). With NG Larsson we generated the MitoPark mouse, first genetic model of Parkinson's disease (Ekstrand et al PNAS 2007). We generated the MemoFlex mouse that demonstrates the need to down-regulate NgR1 in forebrain neurons in order to form lasting memories (Karlén et al PNAS 2009). We used the mtDNA mutator mouse to demonstrate that germline mitochondrial DNA mutations aggravate ageing and can impair brain development (Ross et al Nature 2013). Current focus is role of the Nogo signaling system and structural synaptic plasticity for the formation of lasting memories. Recent papers: Karlsson et al NgR1: a tunable sensor regulating memory formation, synaptic and dendritic plasticity. Cerebral cortex 2016, Karlsson et al Front Mol Neurosci 2017, Lai et al J Neurotrauma 2018, Chen et al J Neurochem 2019.