This document discusses seizure semiology and classification. It begins with an overview of seizure types including motor, aura, dialeptic, autonomic, and special seizures. Motor seizures are further divided into simple and complex seizures. Aura symptoms are described and their localizing value discussed. Dialeptic seizures include absence and complex partial seizures. Autonomic seizures must have objective evidence of autonomic changes. Special seizures include atonic, astatic, negative myoclonic, akinetic, aphasic, and hypomotor seizures. Lateralizing signs and their localizing value are then reviewed. Finally, generalized and focal epilepsies are contrasted, and features of frontal lobe seizures are outlined.

1. Seizure Semiology
localisation and lateralisation
Dr. Vinayak Rodge
DM Neurology

2. Semiology
 That branches of linguistics concerned with
signs and symptoms
Ictus
 A sudden neurologic occurrence such as a
stroke or an epileptic seizure
Glossary of 2001 ILAE report
Epilepsia 42(9):1212-8, 2001

3. Detailed Analysis of Seizure
Semiology
 Seizure - main symptom of epilepsy
 Seizure control - target of treatment
 Presurgical workup
 Differentiate between epileptic and nonepileptic
seizures

4. Seizure Semiology
 1998, Lüders et al.
Semiological seizure classification
 2001, ILAE Commission Report
Glossary of descriptive terminology for
ictal semiology

5.  Motor seizure
Epileptic Seizure
 Motor sphere
Prominent
Features
Semiological Seizure Classification
Lüders et al. (1998)
 Aura
 Dialeptic seizure
 (Autonomic aura)
Autonomic seizure
 Sensorial sphere
 Consciousness
 Autonomic sphere

6. Auras
 Somatosensory
 Auditory
 Olfactory
 Abdominal
 Visual
 Gustatory
 Autonomic
 Psychic
 Unclassifiable

7. Aura features Lateralising and localising value
Visual Flashing light of different colour ,circular, crossing
midline
Contalateral to area 17 and 18,
v illusion- v. association cortex parito-
temporal
Auditory Positive-“buzz”, noise : Negative-loss hearing. Heschells gurus in STG, LTLE
Olfactory Unpleasant smells Mesial temporal lobe epilepsy (high %
have amygdala neoplasm)
Gustatory Unpleasant taste insula
Somato-
sensory
Tingling, numbness, unpleasant heat and pain If u/l –c/l prim. Sensory cortex
If b/l-supplementary sensory motor area,
second sensory-motor area(superior
sylvian or posterior to insula)
Autonomic
aura
Subjective sensation of palpitation, sweating,
goose bumps
insula
Abdominal Nausea, tenseness, knot rolling, butterfly .
Mainly localise to epigastriam . Sensation of
increase peristalsis (van buren assesed same with
gastric balloon during aura )
Temporal (mc) frontal ,insula
Psychic Fear, elation ,déjà vu (inappropriate feeling of
familiarity ) ,jamais vu .
No lateralising value , localise to mesial
temporal lobe (right )

8. Dialeptic Seizures
“Dialeptic”, old Greek, means “to interrupt, stand
still, or pass out”
Alteration of consciousness
Episodes of unresponsiveness or decreased
responsiveness.
 Associated with complete or at least partial
amnesia for the episode
• it can be absence seizures (dialeptic seizures with
a generalized ictal EEG) and complex partial seizures
(dialeptic seizures with a focal ictal EEG).

9. Generalized absence seizures
seizuresuspension of awareness and arrest of activity
Typical absence-
•sudden onset without any aura ,
•brief duration, typically less than 15 seconds,
•sudden termination without any postictal state.
•Generalized 2.5 to 4 hz spike and wave activity.
Atypical absence-
•Slower loss of awareness and more gradual recovery
as well as more prominent motor manifestations.
•Slower frequency less than 2.5 hz

10. Dialeptic seizures
features Absence Complex partial
Frequency Frequent many per day Less frequent
Onset and progression Abrupt and minimal slow
Aura ,automatism None or rare common
Motor signs Rare or minimal common
duration Brief ,<15 sec minutes
Postical confusion None common
Postictal dysphasia none Common if originating from
dominant lobe
Hyperventilation Induce the seizure No effect
Sleep activation none common

11. Autonomic Seizures
 Objective proof of the autonomic
alteration (i.e., tachycardia documented
by EKG monitoring)
vs Autonomic Aura

12. Autonimic seizures Lateralising and localising value
Pilomotor seizure- May spread in
jacksonian march (spread unilaterally to
adjacent body part )
Ipsilateral to seizure onset zone. Localisation
poor
Ictal vomiting /retching Temporal (mainly) ,insula
Ictal spitting Right temporal lobe
Ictal hyper salivation Mesial temporal , lateralise to non dominant
hemisphere
Autonomic seizure (must have objective
evidence )
Must be documented , for example – ictal
tachycardia must be documented with ECG

13. Motor Seizures
 2 major subgroups
Simple : “Simple”, unnatural
Reproducible by direct stimulation of the
primary motor cortex
Complex : Complexity of movement
Generated by widespread neuronal
matrices, natural but Inappropriate for the
situation

14. Simple Complex
Myoclonic
Tonic
Epilepticspasm
Clonic
Tonic-clonic
Versive
Hypermotor
Automotor
Gelastic
Subtypes
- duration of the muscle contraction
- rhythmicity of movement repetition
- muscles involved

15. Simple
motor
seizure
features Lateralising and localising value
Clonic Series of recurrent regular myoclonic
contractions at rate of 0.2-5/sec
Contralateral to primary motor cortex.
In- frontal involve earlier .
Secondary generalisation started on
contralateral side and ends on ipsilateral (“end of
seizure paradoxical clonus” ).
Asymmetric seizure termination rare in prim.
GTCS
Myoclonic Short muscle contractions lasting <400ms Generalized epilepsy
Epileptic
spasm ( few
sec. to min )
Symmetric Muscle contraction either tonic
or myoclonic predominantly affect trunk
and proximal axial muscles followed by
extension and abduction of the arms in a
“salaam position”. , usually appear in
clusters . ,variable duration .
Generalized .
focal –parieto-occipital
Mechanism -not been clearly determined
but involvement of the brainstem raphe nuclei
and spinal pathways has been suggested
Versive
seizure
forced and involuntary turning of the head
and eyes in one direction with neck
extension resulting in a sustained
unnatural position .
Symptomatic zone- frontal eye field.
Versive seizures appear earlier in- frontal lobe
origin than TLE (can be the first sign in FLE ).
Versive seizures – lateralized to contralateral
hemisphere, specially when within 10 seconds
before secondary generalization.

16. Simple motor
seizures
Features Lateralizing and localizing value
Tonic •Sustained muscle contractions >3 s that leads
to  tonic posturing
•Tonic contraction of chest and abdominal
muscle- “tonic epileptic cry”
Secondarily generaliztion -
have a typical “motor sequence-
1. The tonic face seizure and the versive
seizure lateralize contralateral side.
2. The fencing position lateralizes
contralateral to the raised arm .
3. The asymmetric tonic limb posturing “sign
of four” lateralizescontralateral to the
extended arm
Most commonly- frontal lobe epilepsy
(62.2%) mainly bilateral and
rarely temporal lobe epilepsy (1.7%)
(only unilateral tonic seizures ).
if clearly unilateral lateralize to
contralateral
Tonic clonic •Generalized epilepsy - start with symmetrical
tonic posturing of all the limbs followed by a
“jittery” phase  clonic activity of all four
extremities.
• Focal epilepsies – seconadary generalization
almost always preceded by other seizure types
and the tonic phase is usually asymmetric.

17. Complex
motor seizure
Features Localising and lateralizing value
Hypermotor movements involve more than one articulation and
resemble normal movements mainly the trunk and
proximal segments of the limbs.
Ex. peddling movements, running, etc.
May resembles sexual activity, like violent writhing,
thrusting and rhythmic movements of the pelvis,
arms and legs, picking and rhythmic manipulation of
the groin or genitalia.
Consciousness may be preserved.
Mostly during sleep
Most originate from the orbital or
mesial frontal regions.
may be from temporal lobe and
insula.
Automotor Mainly involves distal segments of the hands, feet,
mouth and tongue.
Automotors can be unilateral or bilateral . Unilateral
automotors is likely a manifestation of limb
dystonia in the contralateral limb.
95% are associated with altered consciousness.
Typical of TLE but occasionally
with FLE.
Frontal automotor are shorter .
Unilateral automatisms are more
frequently lateralize to ipsilateral .
Gelastic main motor manifestation is “laughing” .
In 50% of the cases hypothalamic hamartomas were
detected by MRI.
However extrahypothalamic
structures are anterior cingulate
region- frontal, parietal and
temporal lobes

18. AUTOMATISM
•Natural ,repetitive coordinated motor activity that is
inappropriate to the situation .
•Automatism are usually associated with altered
sensorium and amnesia.
 Oro-alimentary- lip smacking/ licking, chewing,
swallowing.
 Manual automatism- involving hand.
manipulative ( imply interaction with nearby objects). and
non manipulative
 Pedal automatisms-involving feet.
 Hyperkinetic- bicycling, pelvic thrusting.
 Gelastic-involuntary laughter.
 Dyscrystic -involuntary crying

19. Special Seizures
All seizures are negative or inhibitory motor seizures
except the aphasic seizures that mostly represent negative
cognitive seizures
 Atonic seizures
 Astatic seizures
 Negative myoclonic seizures
 Akinetic seizures
 Aphasic seizures
 Hypomotor seizures

20. Special
seizure
Features Localization and
lateralization
Atonic
seizures
loss of postural tone with falls or head drop.
Most frequently in -symptomatic generalized epilepsies (Lennox-
Gastaut syndrome) and are usually preceded by a generalized,
proximal myoclonic seizure resulting in an abrupt fall.
Generalized. (LGS )
Focal - seen in FLE and TLE.
these are slower falls and
rarely  significant injuries.
Astatic
seizures
It consist of epileptic falls.
Most commonly are due to a myoclonic seizure f/ b an atonic . But
it can be due to atonic seizures .
Hypomotor
seizures
Decrease or total absence of motor activity.
Only used in whom consciousness cannot be tested during or after
the seizure (newborns, infants ,children < 3 yr mentally retarded)
In focal epilepsy- temporal
and parietal lobe epilepsy.
Akinetic
seizures
Inability to perform voluntary movements.
The diagnosis only be made in patients who are conscious and
cooperative, i.e. they try to perform a movement but are unable to
do so (apraxia).
Localization -negative
motor areas in the mesial
and inferior frontal gyri.
Negative
myoclonic
seizures
A very brief loss of muscle tone of (<400 ms ) which is appreciated
when the affected extremities are elevated or engaged in other
activity. The movement observed are similar to observed in
asterixis.
U/L lateralise to the post-
central
cerebral cortex .
Aphasic
seizures
Patient is aphasic despite preserved awareness and memory.
Can also present as status epilepticus.
Lateralize to the dominant
hemisphere

21. I. EPILEPTIC SEIZURE
1. Motor seizure
Simplea
Complexb
Tonica
Versivea
Hypermotorb
Clonica
Tonic-clonic
Automotorb
Myoclonica
Epileptic spasma
Gelastic
2. Aura Somatosensorya
Auditory Olfactory Gustatory
Summary of Lüders Classification
Psychic
Visuala
Autonomica
Abdominal
3. Dialeptic seizureb
4. Autonomic seizurea
5. Special seizure Atonica
Akinetica
Astatic
Aphasicb
Hypomotorb
Negative myoclonica
II. PAROXYSMAL EVENT Organic Psychogenic
a: Localizing modifiers (L, R, axial, gen, bilat, asymm; hand,etc)
b: Lateralizing modifiers (left hemispheric or righthemispheric)

22. SEMIOLOGY :LATERALIZATION
AND LOCALIZATION
LATERALIZATION LOCALIZATION
HEMISPHERICAL
RIGHT
LEFT
DOMINANT
NON DOMINANT
LOBAR
TEMPORAL
EXTRATEMPORAL
(FRONTAL PARIETAL OCCIPITAL)
SUBLOBAR
MESIAL TEMPOTAL/LATERAL TLE
SMA/ MOTOR AREA
MESIAL /LATERAL OLE

23. LATERALIZATIONIPSILATERAL CONTRALATERAL
U/I limb automatism U/L clonic movement
Early head deviation U/L dystonia
u/l blinking Late head or eye turning
Post ictal nose wiping Ictal akinesis
Asymmetrical termination of clonic jerks
followed by GTCS
Post ictal paresis
Whole body turning
ATLP
DOMINANT NON-DOMINANT
Ictal aphasia Ictal speech
Post ictal dysphasia b/l automatism with preserved
consciousness
Ictal smile. Spitting, vomiting

24. Hippocampus Arrest
Insula/ Amygdala Epigastric aura , salivation
Operculam Oro-alimentary automatism
Basal ganglia Limb dystonia
SMA ATLP (asymmetric tonic limb movement)

25. Lateralising sign Lateralizing value Symptomatogenic zone
Unilateral dystonic posturing contra lateral Activation of BG , TLE
Hemi field visual aura contra lateral Broadman area 17-19 and
adjacent area of OLE
version contra lateral Broadman area 6 and 8
Ictal aphasia and dysphasia dominant Impairment of language
areas
Automatisms and preserved
consciousness
Non dominant , Unknown , left or bilateral
hippocampal impairment,
TLE

26. Lateralising sign Lateralising value Symptomatogenic zone
Post-ictal palsy 93 % contra lateral Area 4 and 6
Post-ictal nose wiping 92% ipsilateral Unknown , TLE
Figure of 4 sign 89% contra lateral SMA , prefrontal area , TLE,
ETLE
Unilateral sensory aura 89 % contra lateral Area 1,2,3
Tonic activity 89% contra lateral SMA , also possibility of
broadman area 6, , anterior
cingulate gyrus and
subcortical structures FLE

27. Lateralising sign Lateralising value Symptomatogenic zone
Ictal speech 83 % non dominant Areas other than those
involved language
production
Clonic activity 83% contra lateral Area 4 and 6 .FLE
Unilateral ictal eye blinking 83% ipsilateral unknown
Ictal vomiting 81 % non dominant Medial ,lateral superior and
inferior structure of non
dominant temporal lobe and
papez circuit
Ictal spitting 76 % non dominant Possible asymmetry of CAN

28. Generalized epileptic seizures
These are conceptualized as
originating at some point
within, and rapidly
engaging, bilaterally
distributed networks. …can
include cortical and
subcortical structures, but
not necessarily include the
entire cortex.
www.ilae.org

29. GENERALIZED SEIZURES
1. Absence –typical, atypical
2. Myoclonic
3. Clonoc
4. Tonic
5. Tonic clonic
6. Atonic

30. Focal epileptic seizures
These are conceptualized as
originating within networks
limited to one hemisphere.
These may be discretely
localized or more widely
distributed.…
www.ilae.org

31. Focal epilepsies
Simple partial seizures ,
Complex partial seizures.
Focal seizure semiology by localization
•Frontal lobe epilepsy
•Temporal lobe epilesy
•Parietal
•Occipital
•Insular

32. Symptomatogenic areas
Left hemisphere, lateral aspect

33. Symptomatogenic areas
Left hemisphere, mesial aspect

34. Symptomatogenic areas
Left Insula

35. Frontal lobe seizures
•Sudden onset and offset
•Short duaration <2min ,frequent .
•Nocturnal frequency
•Early motor signs ,Dystonic posturing
•Bimanual –bipedal automatism
•Little or no postictal cofusion
•Frequent vocalisation
•Stereotyped
•Multiple in single night
•No wandering/ complex directed behavior
•Recall present

36. localisation Semiological features
Primary motor cortex Clonic seizure with or without jacksonian march and todd’s palsy,
cortical myoclonus, consciousness preserved
Dorso-lateral
premotor
Complex bizarre automatism ,forced acting is common
Supplementary motor
cortex
Asymmetrical tonic seizures, well known ‘fencing posture’ I/L
arm flex and C/L extended (figure of ‘4’) , short duration ,occur in
cluster frequently arise out of sleep .ictal vocalisation
Mesial frontal hyperkinetic motor behaviour, ictal expression (emotions)
Frontal eye field (+/-
broca’s)
Eye and head deviation ,ictal vocalisation or speech arrest (with
broca’s)
Orbito-frontal and
polar
Hyperkinetic automatism with agitation , duration-short post-
ictal –brief or nonexistent ,risk of misdiagnosis as psychogenic
seizure
Rolandic or Frontal
opercular area
Facial clonic movement ,swallowing hyper salivation, speech
arrest
Non localising Rare ,staring spell, difficult to distinguish frontal absence
ADNFLE autosomal
dominant nocturnal
FLE
Autosomal dominant ,During sleep ,Like parasomnia –jerky ,
dystonic posturing ,bending rocking

37. Insular epilepsy
Specific features
•Hypersalivation is very common
•Choking
•Throat sensation
•Peri-oral paresthesia
•Autonomic –retching palpitations
•Variable semiology

38. TEMPORAL LOBE EPILEPSY
AURA- Common ( epigastric )
DURATION- 1-2 min and more
FREQUENCY- Few per month
ONSET- slow behavioural arrest, and stare
AUTOMATISM- Simple oro-alimentary
VOCALISATION- Simple speech
GENERALISATION- Uncommon
POSTICTAL- Confusion , aphasia up to minutes

39. Differences medial and lateral TLE
MTLE ( aura, arrest,
automatism, amnesia)
LTLE
Epigastric aura (MC) ,olfactory ,psychic
(fear)
Auditory, cephalic (vertiginous illusion )
,experimental , complex aura
Motionless stare (behr arrest ) Anxious ,agitated behaviour
Speech arrest in dominant Vocalization
Early oro-alimetary and hand automatism Early complex automatism (gross truncal)
I/L limb automatism and C/L dystonic
posturing
Less automatism, no dystonia.
Less sec. generalization Frequent sec. generalisation

40. Temporal Extra-temporal
Limbic aura Aura (Area specific)
Hypomotor activity , stare motionless
arrest ( behr arrest )
Hypermotor ,vocalization
Complex motor movement Primary motor movement
Dystonic posturing Tonic posturing
Slow evaluation Fast evolution
>1 min. duration brief

41. Temporal plus /pseudotemporal
Early motor features (version, eye deviation)
ET aura –sensory and throat sensation
Early age
No antecedent event
High frequency ,clustering
Frequent generalisation

42. Clinical characteristics of temporal
and frontal CPS
CLINICAL TEMPORAL FRONTAL
AURA Common, epigastric Vague, nonspecific
DURATION 1-2 min Brief 10-60 sec
FREQUENCY Few per month Several per week
ONSET Slow behavioural arrest, and stare
,sleep activation
Abrupt forceful movement,
frequent sleep activation
AUTOMATISM Simple oro-alimentary Complex bipedal bizarre
SPEECH Simple verbalization speech in non
dominant seizure
Complex ,loud vocalization
(grunting ,screaming )
GENERALISATION Uncommon Common
POSTICTAL Confusion , aphasia up to minutes Absent or minimal

43. Parietal lobe epilepsy
•Next most likely source of seizure after TLE and FLE
•Best recognized manifestation is -sensory aura –
numbness, tingling, pins and needles, burning pain.
•With sensory march- post central primary sensory
cortex .
•Without sensory march- second sensory area
(parietal operculum )
•Seizures without parietal lobe symptoms- most of
have no parietal symptoms but rather manifestation
resulting from spread to occipital ,temporal, or frontal.

44. Occipital lobe epilepsy
SENSORY SYMPTOMS-
•VISUAL HALLUCINATION
cardinal symptom (20-70 %)
brief, multicloured and circular
may be only manifestation
postictal headache (nonspecific -TLE)
•VISUAL ILLUSION
•BLINDNESS
MOTOR SYMPTOMS –
•b/l blinking, nystagmoid eye movements, eye deviation (c/l)
•One distinctive feature –it develop and propogate posteriorly
very slowly (Eye deviation seen in OLE is much slower than in
FLE and TLE )

45. Panayiotopoulos syndrome
•Common idiopathic childhood occipital seizure
disorder
•Often prolonged
•Predominantly autonomic symptoms

46. Gelastic (laughing)
Hypothalamic –brief ,no mirth/emotions ,many,
preserved awareness.
Frontal- unnatural, no mirth/emotions ,automatism ,
preserved awareness
Temporal- post temporal, amygdala, natural, prolong
mirth/emotions
DD –GELASTIC SYNCOPE.

47. Dacrystic- quiritarian (crying)
Post temporal –with tears sometimes
Frontal- unnatural ,forced
Hypothalamic-brief

48. Rare report of seizure
•Seen is cerebellar ganglioglioma
•Characterizes by hemifacial twitching ipsilateral to
lesion and at same times contralateral head and eye
deviation or contralateral nystagmus.

49. Clinical approach to patient with
epilepsy
Age of seizure onset-(neonatal ,childhood, juvenile,
elderly)
Warning symptoms -Aura (abdominal, sensory,
visual, no aura )
What happens during seizures -(awareness,
automatism, incontinence/tongue bite )
Post-ictal period- (confusion, aphasia, preserved
speech, paralysis , immediate recovery-no confusion )
Diurnal variation (early morning/ after awakening,
any time, during sleep )

50. Thanks