Table 2.

Neuron types in recording sample

Area	Movement related				Cancelation related
	Increased		Decreased	All
Regular	Early onset	CT before SSRT			CT after SSRT	All
Pre-SMA	73	31	13	117	5	17	22
SMA	111	22	17	150	2	16	18

Movement-related neurons have activity that is significantly different from baseline during the movement period. Cancelation-related neurons have higher activity during canceled trials than noncanceled trials. We divided them by whether their cancelation time (CT) was before or after the SSRT. Some movement-related neurons with decreasing activity were also classified as cancelation related.