We took him to see the neurologist, and her analysis was that Bensen was showing symptoms of diffuse forebrain disease, and that there were a number of potential causes, including a developmental malformation resulting in hydrocephalus and/or hepatic encephalopathy. Bensen was put on the special diet for dogs with liver shunts and meds to see if he started to show any signs of improvement. Unfortunately his behavior was not changed at all, and the neurologist and vet both felt that even if there was a liver shunt, his behavioral issues were unlikely to clear up and his quality of life would not improve.
This was such a difficult decision but one that we made so that Bensen could finally rest and be at peace.