Final answer:
Mr. Garcia's symptoms are consistent with Parkinson's disease, a degenerative disorder of the central nervous system that affects movement and muscular control. Medication has not significantly improved his symptoms.
Step-by-step explanation:
Mr. Garcia's symptoms are consistent with Parkinson's disease, which is a degenerative disorder of the central nervous system that affects movement and muscular control. The symptoms described, such as hand tremors, slowness of movement, stiffness, and a hunched posture, are all characteristic of this condition. It is important to note that Mr. Garcia's medication, which is dopamine-related, has not significantly improved his symptoms. In advanced stages of the disease, dementia and depression can also occur.