Drives are chemicals too. Let's see...The ChemicalNames.catalogue wrote:
"Hunger for protein"
# chemical 150
"Hunger for carbohydrate"
"Hunger for fat"
"Coldness"
"Hotness"
"Tiredness"
"Sleepiness"
"Loneliness"
"Crowded"
"Fear"
"Boredom"
# chemical 160
"Anger"
"Sex drive"
"Comfort"
Chems 149 to 162 as it seems. "Comfort" is home sickness in this case. Just use an agent that CHEMS these to the right values. CHEM has no learning effect, so they will not associate the in- or decreasing drives with random actions they do when you manipulate them.
EDIT: Got ninja'd by Malkin. Better do not go for DRIV in this specific case. DRIV does have a learning effect of sorts, so whatever your norn is doing in the moment you change the drives, they will associate it with their action, which might cause into pretty funny (though unwanted) cases of EES.
Also, chemical numbers and drive numbers are different, so the list I posted would not apply either.