Figure 6.

Preferred direction distributions for simulated and actual CN neurons. A: polar histogram of active PDs combined across monkeys (N = 75 neurons). Outer circle represents 15 neurons with PDs in that bin. All subsequent plots in this figure have the same layout as A. Neurons included in this figure were sinusoidally tuned in both active and passive conditions, from CN regions of the array, and appeared to receive inputs from the upper trunk, shoulder, or proximal arm. B: passive PD distribution for CN neurons. C: PD distribution for all 1,000 simulated CN neurons receiving input from a muscle spindle of a single randomly chosen muscle in the proximal arm. D: PD distribution for simulated CN neurons, having inputs corresponding to those actually mapped for recorded neurons. E: actual PD distribution of the same spindle-receiving neurons in D (n = 52). CN, cuneate nucleus; PD, preferred direction; RF, receptive field.