TIA (limb-shaking) or seizure in elderly

The following paragraph was taken from UpToDate on 2011/12/07:
Transient ischemic attacks (TIAs) may be mistaken for seizures, but they may also induce seizures.

Brain ischemia produces reduced neural activity and "negative" symptoms such as hemiparesis or hemisensory loss. In contrast, seizures usually cause "positive" symptoms from neural overactivity. So called "limb-shaking" TIAs may represent a source of diagnostic confusion in this regard. This somewhat unusual manifestation of cerebral ischemia typically occurs in the setting of high-grade carotid stenosis.

Certain symptoms, such as aphasia, can occur in TIA or seizure. While an isolated episode of aphasia is more likely to be a TIA than a seizure, aphasic seizures are well described. In general, ictal aphasia is progressive, developing over minutes from dysphasia to paraphasic errors, and culminating in a global aphasia. In contrast, TIA symptoms develop abruptly and typically do not evolve. Although TIA is commonly considered as a cause for confusional episodes, confusion is rarely a manifestation of TIA.

Chronic, recurrent stereotyped events are much more likely to be seizure than TIA. Transient loss of consciousness only should not be diagnoed as TIA. However, since syncope can rarely occur in association stroke, care should be exercised in the evaluation of patients with syncope and limb weakness which can actually be Todd's paralysis after a seizure of no witness.