On and off head numbness past few days and 1 occurrence of right thumb paralysis temporarily whilst weakness in index and middle finger causes?

Head numbness? The differential includes cerebral vasospasm, TIA due to hypotrension or cardiac arrhythmia with a fixed stenotic lesion, acephalgic migraine and focal seizure. Focal seizure is less likely because of the absence of initial "positive symptoms" (Parasthesias) If the head numbness and hand symptoms are unrelated think CTS. If deficits last 24 hours or greater think MS or ICS (not quite MS)