Hey Larry,
The plant pictured looks like a very old, etiolated Dieffenbachia (a.k.a. dumb cane). Even with a healthy plant, Dieffenbachia are not allowed to grow so large because they don't retain the "full" appearance of a young plant. You may want to propagate it and start over.
If not, could you move the plant to a spot with stronger light? Bright light shaded by a curtain, that is. Maybe supplement it's light with fluorescent growlights suspended above it? Also, the pot looks too small for a plant so large...gently pull the stem of the plant out of the pot, including all the potting mix. It the rootball appears to be tightly wound around the inside of the pot, the plant's health is being affected, so repot.
Additional questions are welcome.
Chris