Depression. Whom should we consult?

My father had a long 2 months of hospitalization after a bypass surgery, where he developed sternal infection and later developed hyponatremia (low sodium). A neurologist was consulted and he was diagnosed with a probable case of extrapontine demyelination. Although over time, he showed better signs and within next 15 days went from being bed ridden to doing everything by himself after some physiotherapy. Although after he realized he spent almost 3 months in hospital, he started getting depressed. Now a days he stays in a kind of crying mode (no tears), doesnt' talk properly (talks in a weepy tone), has no confidence in himself and says he can't even move by himself (although he can). He even doesn't want to go out anywhere. At times he blabbers weird things e.g. before holi, called the electrician for fitting lightings, also at times doesn't realize the nature calls. What kind of treatment do we seek for him? Neuro? pyschiatric? Whom should we consult?