brain "buzz" leads to falls

About my father, age 90

Occasionally, without notice, a "buzz" in the brain.  From his description, it sounds "electrical."  If on his feet when this occurs, all muscle control in legs is lost ("they just give out") leading to a fall.  

History:
artery disease, carotid, 20-25 years ago.  has PAD in legs.  Cholesterol now perfect without meds
early stage ALZ diagnosis several years ago, but you would never know it talking to him, uses galantamine
uses a 'blood thinner' phentermine(sp?)
blood pressure is normal 120-135 / 65-80, with a heart rate of 72 bpm, no meds.

Can you provide a range of possible explanations?

So sorry about earlier MULTIPLE posts with this title.  Cat stepped on keyboard return button.

1st_Son

[Abhijeet Deshmukh, MD]

Hello.

The buzz in the brain could be a momentary reduction of blood supply to specific areas of brain, leading to the fall. I would advice an MRA (Magnetic Resonance Angiography) to find out the area.

How is his Alzheimer's now ? Or has the diagnosis been revised ?

Regards