Sensorimotor maps can be dynamically calibrated using an adaptive-filter model of the cerebellum
Fig 2
Recalibration of a single target map with curvilinear distortion.
a) The left hand panel shows an initially accurate map (green line) in the superior colliculus (SC), with artificially induced curvilinear distortion (red line) (details in Methods). The shifts in the map to correct for the distortion are dependent on the location in the map, and are indicated by black arrows. The learnt cerebellar recalibration of the distorted grid (teal line) is shown in the middle panel. The right hand panel shows the combined learnt weights in the x- and y-directions corresponding to each coarse coded parallel fibre signal (weights initially zero). b) Time course of recalibration, showing how RMS errors in orienting responses change with number of target presentations. c) Example of learnt dynamic cerebellar recalibration. The left-hand panel shows the shift in the map (red arrow) required to produce an accurate orienting response to the inaccurate target location provided by the distorted map. The centre panel shows the coarse-coded, normalised parallel fibre signals produced by the inaccurate target location. The right hand panel shows that after learning the parallel fibre signals now shift the map by just the required amount to produce an accurate response.