is the sensation of motion around a stationary person. Most often, these attacks of vertigo are due to a benign cause, usually a process called benign paroxysmal positional vertigo (BPPV). In BPPV, a patient experiences short-lived dizziness
(usually seconds) that is brought on by certain changes in the position of the head, which cause movements of small stones in the inner ear which alter our perception of movement. These episodes may be accompanied by nausea related to the dizziness.
The same sensation of vertigo can also be due to changes within the brain, rather than in the ear. Migraines, infection, inflammation and stroke are all capable of causing such symptoms. Difficulty with speaking is a symptom that should be taken very seriously, as this is not typically associated with repeated episodes of benign vertigo (such as BPPV). Most concerning is that the slurring of words could be a sign of a stroke or a transient ischemic attack (essentially a mini-stroke that doesn't leave permanent damage). Because it is impossible to tell without further testing, your mother should get in touch with her physician as soon as possible to assess her risk factors for stroke and make sure that a more severe cause of her dizzy episodes is not at play.