<p>A focal slowing, if seen in the EEG, can indicate trauma, tumor, a lesion, or a healing grey matter injury. If delta is showing it can indicate an injury where the white matter is damaged and myelination is affected, if theta is showing it could indicate a grey matter injury (such as we would see in whiplash or a concussive injury). If the focus is at the posterior temporal lobes, good chance it is a cerebral vascular issue.</p><p><br></p><p></p>