Yes. Berries contain water-soluble vitamins (vitamins B and C), which are unstable when heated or when stored incorrectly. In that sense, refrigerating your berries is a better option if you want to preserve more of their micronutrients. However, if you leave your berries at room temperature for a few hours they will not lose 100% of their healthy properties. Only the concentration of vitamins B and C will be more likely to decrease.