Neural activation in humans during a simple motor task differs between BDNF polymorphisms.
The BDNF Val66Met polymorphism has been linked to decreased synaptic plasticity involved in motor learning tasks. We investigated whether individual differences in this polymorphism may promote differences in neural activity during a two-alternative forced-choice motor performance. In two separate sessions, the BOLD signal from 22 right-handed healthy men was measured during button presses with the left and right index finger upon visual presentation of an arrow. 11 men were Val66Val carriers (ValVal group), the other 11 men carried either the Val66Met or the Met66Met polymorphism (Non-ValVal group). Reaction times, resting and active motor thresholds did not differ between ValVal and Non-ValVal groups. Compared to the ValVal group the Non-ValVal group showed significantly higher BOLD signals in the right SMA and motor cingulate cortex during motor performance. This difference was highly consistent for both hands and across all four sessions. Our finding suggests that this BDNF polymorphism may not only influence complex performance during motor learning but is already associated with activation differences during rather simple motor tasks. The higher BOLD signal observed in Non-ValVal subjects suggests the presence of cumulative effects of the polymorphism on the motor system, and may reflect compensatory functional activation mediating equal behavioral performance between groups.
Department of Psychiatry, University of Ulm, Ulm, Germany; Max Planck Institute for Neurological Research, Cologne, Germany; Neurological Department, University of Cologne, Cologne, Germany.
Lizbeth
L
Cárdenas-Morales
Department of Psychiatry, University of Ulm, Ulm, Germany.
Georg
G
Grön
Department of Psychiatry, University of Ulm, Ulm, Germany.
Eun-Jin
EJ
Sim
Institute of Pharmacology of Natural Products and Clinical Pharmacology, University of Ulm, Ulm, Germany; Research Department, Federal Institute for Drugs and Medical Devices, Bonn, Germany.
Julia C
JC
Stingl
Department of Psychiatry, University of Ulm, Ulm, Germany.
Thomas
T
Kammer
D000328:Adult; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D002755:Choice Behavior / Q000502:physiology; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex / Q000033:anatomy & histology / Q000502:physiology*; D009473:Neuronal Plasticity; D020641:Polymorphism, Single Nucleotide; D011597:Psychomotor Performance; D011930:Reaction Time; D013647:Task Performance and Analysis
D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human