Electrolytes

I am currently working on a PhD in psychology and I am about 4 classes in. I have always wanted to do neuroscience and, while in my current program, I applied to a neuroscience program and I got in. I was actually surprised. Neuroscience was why I majored in psychology to begin with. The neuroscience program is a Master's program. Everyone in my family is supportive of me getting the PhD but at the same time I feel pulled to the neuroscience program. It would be a second Master's degree for me. At this moment I can only afford to go to one program. I do not know which way to go.