Figure 3.

Effect of the sight of the monkey’s own arm and of a detached, stuffed monkey arm on responses of premotor neurons. For each neuron, three SIs were calculated. SI_{visual+proprioceptive} indicates the amount that the visual RF moved with the monkey’s arm, when the arm was uncovered and within view. SI_{proprioceptive} indicates the amount that the visual RF moved with the arm, when the arm was covered from view. SI_visual indicates the amount that the visual RF moved when the monkey’s arm was blocked from view and a stuffed arm was placed in view and moved to different positions. SI_{visual+proprioceptive} − SI_{proprioceptive} provides an estimate of the amount that the sight of the arm influences the neuron. SI_visual provides an independent measure of the same property. These two measures were highly correlated. The line at slope = 1 is also plotted.