GCA error

老師:
我在跑gca時跳出下列視窗 
Error using=>rest_gca_coefficient at 63
REST doesn’t support the selected ROI definition now,

matlab中出現以下訊息:
Error using ==> rest_gca_coefficient at 63
REST doesn't support the selected ROI definition now, Please check:
D:\CO_3group\smooth\CBVmask_Resliced\Resliced_caudate.nii
63#line,           rest_gca_coefficient,      in "C:\Program Files\MATLAB\R2008b\REST_V1.8_121225\REST_V1.8_121225\rest_gca_coefficient.m"
957#line,         btnComputeGCA_Callback,    in "C:\Program Files\MATLAB\R2008b\REST_V1.8_121225\REST_V1.8_121225\rest_gca_gui.m"
96#line,           gui_mainfcn,   in "C:\Program Files\MATLAB\R2008b\toolbox\matlab\guide\gui_mainfcn.m"
39#line,           rest_gca_gui,  in "C:\Program Files\MATLAB\R2008b\REST_V1.8_121225\REST_V1.8_121225\rest_gca_gui.m"
0#line,             @(hObject,eventdata)rest_gca_gui('btnComputeGCA_Callback',hObject,eventdata,guidata(hObject)),   in ""
我的mask是用vox 3x3x3的, 且有和smooth後的data對位一致的
不知道是哪裡出了問題,請老師指導一下,謝謝!!