Hi Rod! I believe your plant is Schefflera, aka Umbrella Tree. Could your plant been subjected to a cold draft or blasts of hot air from heating vents? They may shed their leaves for that reason, or if they are moved about( they don't like that). You also have to be careful with watering; they do not like to be overwatered. Make sure the top inch of the soil is dry, use your finger as a gauge, before watering thoroughly. They appreciate some humidity in the winter months and be sure to check for pests. Good luck!