Occipital alpha subharmonics are a normal EEG variant. Unilateral occipital
slowing, however, is associated with focal dysfunction of that particular
side. We report a 10-year-old girl with the incidental EEG finding of unila
teral occipital slowing. MRI of her brain was completely normal and on long
term follow up she remained healthy. Based on her clinical history, normal
MRI of brain, and the character of the slow posterior rhythms, we conclude
that unilateral slow alpha rhythm can be a normal variant akin to alpha sub
harmonics.