//set everything to one diameter:
forsec wholeaxon diam = isegdiam

//corticofugal axon
forsec binzeggerCorticofugal diam = isegdiam*0.9

//first order:
forsec firstOrder diam = isegdiam*0.5

//second order:
forsec secondOrder diam = isegdiam*0.4

//third order:
forsec thirdOrder diam = isegdiam*0.35