Writer's cramp: restoration of striatal D2-binding after successful biofeedback-based sensorimotor training.
BACKGROUND
Previous studies of writer's cramp have detected cerebral sensorimotor abnormalities in this disorder and, more specifically, a reduced striatal D2-binding as assessed by [(123)I]IBZM SPECT. However, empirical data were lacking about the influence of effective biofeedback-based sensorimotor training on D2 receptor binding.


METHODS
To determine whether there is a restoration of D2-binding after successful sensorimotor treatment, pre- and posttreatment SPECTs were compared in five patients with writer's cramp and correlated with improvement in handwriting.


RESULTS
After treatment, the clinical and electromyographic picture appeared substantially improved connected with a significant increase in D2-binding to nearly normal levels similar to normative data in age/sex-matched healthy subjects.


CONCLUSIONS
The current study supported the view that writer's cramp results from a plastic adaptation of a rectifiable nigrostriatal dopaminergic system and that effective sensorimotor training leads to increased efficacy of striatal dopaminergic transmission.
Berger
Hans J
HJ
Department of Medical Psychology, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands. h.berger@neuro.umcn.nl
van der Werf
Sieberen P
SP
Horstink
Casper A
CA
Cools
Alexander R
AR
Oyen
Wim J
WJ
Horstink
Martin W
MW
D000328:Adult; D001549:Benzamides / Q000493:pharmacokinetics; D001676:Biofeedback, Psychology / Q000379:methods*; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000187:drug effects*; D018492:Dopamine Antagonists / Q000493:pharmacokinetics; D020821:Dystonic Disorders / Q000000981:diagnostic imaging / Q000378:metabolism / Q000628:therapy*; D004576:Electromyography / Q000379:methods; D006236:Handwriting; D006801:Humans; D008297:Male; D008875:Middle Aged; D011759:Pyrrolidines / Q000493:pharmacokinetics; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D001549:Benzamides; D018492:Dopamine Antagonists; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; C055743:3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide