In Fitzgerald and Hallpike differential caloric test, cold water irrigation at 30deg centigrade in the left ear in a normal person will produce:

(a) Nystagmus to the right side(Ref. Scott Brown, 8th ed., Vol 2; page 796)If the same is done with warm water the nystagmus will be towards the same side, i.e. left side.Direction changing nystagmus is seen in central lesions.Positional nystagmus is seen in BPPV.