Abstract: Methods and compositions comprising isothiocyanates or derivatives or metabolites thereof, for attenuating or preventing central nervous system tissue damage, and/or improving cognitive function, are disclosed. Treatment of head trauma, spinal cord injury, stroke, aging, neurological diseases, and other insults to the central nervous system that compromise the blood-brain barrier, cause brain swelling, central nervous system cell death, or cognitive or motor dysfunction, by administering an isothiocyanate such as sulforaphane, allyl isothiocyanate, phenylethyl isothiocyanate, or a related compound, is also disclosed.