Consultation regarding speech problem.

My father is 75 year old retired teacher and he started facing difficulty while speeking. Its like some time he wont get words when involved in not very lengthy conversation or sometime words wont be clearly pronounced. This is occassional and some cases he speeks perfectly. Also he has developed a kind of shivering of fingers while holding papers and some time wont be able to write properly or even to sign. Lastly when he had a consultation with a gastroendocrinologist , Dr adviced to take a neuro consulatation when he noticed my fathers fingers were shivering. I would like to know if you have any specific treatment for these kinds of problems mainly speech related which is bothering him alot and also along with that would like to consult for the shivering which he developed recently. I just thought of confirming with you in advance as i need to bring my dad from Kerala for consultation. waiting for your response and to meet you soon based on that. Thanks!!