The symptoms are quite non-specific. The initial symptoms could have been signs of stroke versus TIA, seizure, migraine variant, or even a problem in his cervical spine. Now with mixed symptoms, it makes it more difficult to be certain the cause. Without taking a history and examining your father I cannot narrow the possible causes. I would recommend having a consultation with a neurologist. Your father may need an EEG and perhaps a MRI of his cervical spine (neck). His blood pressure and cholesterol should be controlled. The aspirin is also a good starting point, until these are figured out. I wish I could be of more help, but without more information this is not possible. Good luck.
Forgot to mention my father has mild arthritis and recurrent back pain.