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disintegration of a body part. Rarely the eyes are the only affected body part, and in those
cases the discharge is thought to involve the rostral occipital cortex. Illusion of distorted or
changed body shape is another phenomenon, in which a body part may be felt to be swollen
or shrunken (macro- and microsomatognosia), or elongated or shortened (hyper- and
hyposchematica). The peripheral parts of the extremities and tongue are most commonly
affected. Other described disturbances are unilateral asomatognosia  where absence of a
body part, limb or the hemibody is experienced  and sensation of a supernumerary or
phantom limb. Some parietal seizures may resemble panic attacks.

It is important to note that there is also sensory representation in the posterior insula and in
the supplementary motor area, so seizures involving these parts may have prominent sensory
symptoms4. Awareness of this is crucial when surgical treatment is being considered.

Seizures with visual symptomatology1,3

Seizures from the occipital lobes and the parieto-occipital junction are characterised by visual
phenomena, but visual auras may occur in epilepsy affecting any part of the visual pathways.
Elementary visual hallucinations are most common, especially crude sensations of light or
colours, which may take various shapes, be continuous, steady or moving, or be interrupted
flashes of light. Visual loss, either total or partial, may also occur and is especially common
in children. Transient amaurosis as an ictal phenomenon lasts seconds to minutes, but visual
loss may also occur as a post-ictal deficit. Amaurosis is usually bilateral and may take the
form of a blackout or whiteout.

Formed visual hallucinations are experienced fairly often in epilepsy. Pictures of people,
animals or scenes may be perceived, either static or moving. One subtype is epileptic
autoscopia, where the subjects see mirror images of themselves, sometimes in long-lived
situations. Formed hallucinations are usually brief, and may be associated with slow head and
eye turning, with the gaze towards the direction of the moving images perceived. They may
be associated with various types of visual illusions. Usually, patients are aware of the
unreality of the experience. In comparison with migraine, that is usually associated with sharp
lines and fortification spectra, the visual hallucinations of occipital seizures commonly
comprise coloured blobs of light. As a further distinction, the visual aura of migraine usually
evolves much more slowly, over several minutes.

Visual illusions also occur as a seizure phenomenon, and visuo-spatial perceptions and
topographical sense have been located to the non-dominant parietal lobe. The simplest types
mainly involve visual illusion of spatial interpretation, illumination or colouring of vision, or
movement in space. Perceived objects may appear diminished or enlarged (micro- or
macropsia), altered in shape, squeezed or compressed from above, downwards or sideways,
vertical and horizontal components may be oblique and lines wavy. Lines may be defective
or fragmented, stationary objects seen as moving, or motion appears too slow or too fast. In
some cases, such experiences may be difficult to distinguish from the characteristic illusion
of movement in vertigo. More complex forms include inappropriate orientation of objects in
space, like teleopsia, where objects appear both small and at a distance, or enhanced
stereoscopic vision, in which near subjects seem very close and more distant objects located
very far away. Palinopsia, or visual perseveration, in which visual images recur or persist
after removal of the stimuli, may also occur as a seizure.

Other seizure phenomena from occipital and parietal regions1,3

Ictal anosognosia, apraxia, acalculia, alexia and aphemia may occur in epilepsy from the
posterior brain regions, often presenting as confusional states. Gustatory seizures sometimes
have their origin on the suprasylvian border close to the sensory region for the mouth and