The language of absence epilepsy has changed repeatedly over more than three centuries.
Brief episodes of impaired responsiveness were described long before EEG existed, but physicians disagreed about what they represented, how they related to convulsive epilepsy and even whether some of them should be considered epileptic at all.
The path from petit mal to modern absence terminology was therefore not a simple renaming exercise. It reflects changing ideas about seizure severity, seizure type, EEG pattern and epilepsy syndromes.
This page follows that historical language. It does not replace the site’s modern clinical pages on absence seizures or seizure classification.
1705: an early description by Poupart
Historical reviews usually trace one of the earliest recognisable descriptions of absence seizures to François Poupart in 1705.
The episodes were brief and lacked the dramatic convulsions traditionally associated with epilepsy.
That made them difficult to place within older medical frameworks. A person could appear momentarily absent or disconnected, then rapidly resume what they were doing.
The lack of collapse or prolonged recovery challenged the assumption that epilepsy had to involve a major convulsion.
Tissot and the eighteenth-century clinical description
Samuel-Auguste Tissot described similar brief attacks in 1770.
Tissot’s writings helped bring subtle seizure phenomena into a more systematic medical discussion.
What mattered historically was not only that he described brief lapses, but that he treated them as part of the wider spectrum of epileptic disease rather than as simple inattentiveness.
Modern historians still have to be cautious when retrospectively diagnosing eighteenth-century descriptions, but the clinical resemblance is strong enough that Tissot is routinely included in the history of absence epilepsy.
1824: Calmeil introduces the language of ‘absences’
In 1824, Louis-Florentin Calmeil used the term absences for brief episodes of impaired consciousness.
This was a major linguistic step.
The word did not define an EEG pattern — EEG was still more than a century away — but it captured the observable clinical phenomenon: a transient interruption in ordinary awareness or responsiveness.
The term would survive, unlike several other nineteenth-century labels, and eventually become part of modern epilepsy terminology.
1838: Esquirol and ‘petit mal’
Jean-Étienne Dominique Esquirol is generally credited with introducing the term petit mal in 1838.
Literally meaning ‘small illness’ or ‘small evil’, it was used in contrast with grand mal, the dramatic convulsive seizure.
The terminology classified attacks partly by outward severity.
A major convulsion was ‘grand’. A brief, less visibly dramatic episode was ‘petit’.
That language became enormously influential, but it also created problems that would persist for more than a century.
Why ‘petit mal’ was attractive
The term was simple.
It gave physicians a way to distinguish brief non-convulsive attacks from large tonic-clonic convulsions without needing a theory of underlying physiology.
It was also flexible enough to be used in different ways.
That flexibility eventually became a weakness.
‘Petit mal’ could refer to typical absence seizures, other brief impaired-awareness events and sometimes broader categories of minor epileptic attacks.
As neurology became more precise, the term proved too vague.
Reynolds and ‘epilepsia mitior’
John Russell Reynolds, in his 1861 work on epilepsy, used the term epilepsia mitior — milder epilepsy — for attacks that lacked the full dramatic features of major convulsions.
He provided detailed descriptions of what would now be recognised among the spectrum of absence-like events.
The terminology again reflected apparent severity rather than underlying electroclinical mechanism.
Still, Reynolds contributed to the growing recognition that epilepsy included brief and subtle forms.
Delasiauve and the hierarchy of seizure severity
Louis Delasiauve, writing in the mid-nineteenth century, ranked absences among the least severe seizure manifestations.
This fitted the broader Victorian tendency to organise seizures along a continuum from minor to major attacks.
That model was understandable from outward appearance.
It is also one reason the language of ‘petit’ and ‘grand’ became so deeply embedded.
The limitation is obvious in retrospect: a seizure that looks small can still have major consequences for learning, safety and daily function.
Gowers and the importance of subtle attacks
William Gowers emphasised that brief attacks could be missed unless the history was taken carefully.
He described patients whose episodes involved very little movement and only short interruptions of consciousness or activity.
Gowers’ work reinforced the idea that epilepsy could be clinically subtle and that witnesses’ descriptions mattered.
His approach helped move minor seizures away from being treated as insignificant variants of ‘real’ epilepsy.
‘Petit mal’ did not always mean the same thing
By the late nineteenth and early twentieth centuries, the term petit mal had accumulated several meanings.
Some physicians used it for brief lapses of consciousness. Others used it more broadly for minor epileptic attacks.
Some events we would now classify as focal impaired-consciousness seizures were historically placed alongside absence attacks because both could involve staring, behavioural arrest or brief altered responsiveness.
Without EEG, these disorders could be extremely difficult to separate.
The arrival of ‘pyknolepsy’
At the beginning of the twentieth century, another term appeared: pyknolepsy.
The word derives from the Greek pyknos, meaning frequent, dense or closely packed.
It was used particularly for children who had many brief absence-like attacks each day.
The high frequency of episodes was one of the most distinctive features.
For a time, pyknolepsy was not universally accepted as ordinary epilepsy. Some physicians considered it a separate childhood condition with a different prognosis.
Only later did EEG evidence help establish its epileptic nature.
Why pyknolepsy caused debate
Children with frequent brief absences could otherwise appear physically well.
The attacks might begin and end abruptly, with little or no postictal confusion.
That presentation looked very different from the severe convulsive epilepsy familiar to physicians.
Some children also improved with age, encouraging the belief that pyknolepsy might be a distinct benign disorder rather than an epilepsy.
The debate shows how strongly classification depended on visible clinical behaviour before EEG.
EEG changes the language
The 1930s fundamentally altered the classification problem.
Hans Berger had shown that human brain electrical activity could be recorded. Soon afterwards, researchers began recording characteristic abnormalities during epileptic attacks.
In 1935, the Harvard group associated with Frederic Gibbs, Hallowell Davis and William Lennox described the classic rhythmic spike-and-wave pattern at approximately three cycles per second during petit-mal attacks.
For the first time, a brief clinical absence could be linked with a reproducible electrical pattern.
‘Petit mal’ becomes electroclinical
Before EEG, petit mal was largely a clinical description.
After the 1930s, the term increasingly became associated with a particular electroclinical phenomenon.
A sudden brief impairment of responsiveness accompanied by generalised rhythmic spike-and-wave activity could now be distinguished from other events that looked similar.
This was one of the first major examples of EEG changing seizure terminology rather than merely confirming an existing label.
Psychomotor seizures had confused the picture
Before EEG, brief focal seizures involving behavioural arrest or altered awareness could resemble absence attacks.
These events later became associated with temporal lobe epilepsy and were historically called psychomotor seizures.
EEG helped demonstrate that superficially similar staring episodes could arise from different electrical patterns.
This distinction weakened the usefulness of petit mal as a broad label for every minor attack.
The ‘petit mal variant’ problem
The history became even more complicated when slow spike-and-wave patterns were described in children with severe epilepsy.
In the late 1930s, Gibbs and colleagues used the term petit mal variant for a slower spike-and-wave pattern associated with different clinical features and a poorer prognosis.
That pattern later became associated with the syndrome now known as Lennox–Gastaut syndrome.
The label illustrates how the old petit mal framework began stretching beyond its useful limits.
Typical and atypical absence emerge as separate concepts
As EEG and clinical observation improved, neurologists recognised that not all absence seizures behaved the same way.
Typical absences tended to begin and end abruptly and were associated with relatively fast generalised spike-and-wave discharges, classically around 3 Hz.
Atypical absences often had less abrupt onset and offset and were associated with slower, more irregular generalised spike-and-wave activity, particularly in developmental and epileptic encephalopathies.
The distinction marked another move away from one broad ‘petit mal’ category.
Absence became a seizure type, not a synonym for a syndrome
This distinction is essential.
An absence seizure is a seizure type.
Childhood absence epilepsy and juvenile absence epilepsy are epilepsy syndromes.
A person can have absence seizures as part of different epilepsy syndromes.
That separation became clearer as twentieth-century classification developed and is central to modern terminology.
Childhood absence epilepsy
Childhood absence epilepsy became recognised as a distinct syndrome characterised primarily by typical absence seizures beginning in childhood, together with characteristic generalised spike-and-wave EEG findings.
Historically, many cases that would now fall within childhood absence epilepsy had been called pyknolepsy or petit mal epilepsy.
The newer syndrome terminology combined age at onset, seizure type, EEG findings and clinical course rather than relying on one descriptive label.
Juvenile absence epilepsy
Juvenile absence epilepsy separated another group in whom typical absence seizures begin later and are more often associated with generalised tonic-clonic seizures.
Again, older terminology would often have grouped these patients under petit mal.
Syndrome classification showed that clinically similar absence seizures could occur in different age-related epilepsy disorders.
‘Grand mal’ and ‘petit mal’ begin to disappear
By the later twentieth century, international epilepsy classification increasingly moved away from the grand-mal/petit-mal pair.
The terms were too imprecise.
‘Grand mal’ did not explain whether a tonic-clonic seizure was generalised from onset or evolved from a focal seizure.
‘Petit mal’ could obscure the difference between typical absence, atypical absence and other brief impaired-consciousness events.
Modern classification therefore replaced appearance-based shorthand with more specific seizure terminology.
The 1981 ILAE seizure classification
The International League Against Epilepsy’s 1981 classification formally organised seizures into partial, generalised and unclassifiable groups.
Absence seizures were placed among generalised seizures rather than being treated simply as ‘minor epilepsy’.
This classification relied on both clinical and EEG evidence and helped standardise terminology internationally.
Why ‘absence’ survived
Unlike many historical epilepsy terms, absence proved adaptable.
It described a characteristic seizure phenomenon without implying that the attack was trivial.
It could also be qualified.
Typical absence, atypical absence and myoclonic absence could be distinguished while retaining a common descriptive family.
The term therefore survived successive revisions of international seizure classification.
The 2017 classification
In the 2017 ILAE operational classification, absence seizures appeared under generalised-onset nonmotor seizures.
The classification recognised several forms, including typical absence, atypical absence, myoclonic absence and absence with eyelid myoclonia.
This was a major distance from the nineteenth-century idea of one broad category called petit mal.
The 2025 ILAE update
The ILAE revised seizure classification again in 2025.
The updated system retains absence seizures as a generalised seizure class and lists typical absence, atypical absence, myoclonic absence and eyelid myoclonia with or without absence.
It also removes the older motor-versus-nonmotor division from the main classification framework and uses observable versus non-observable manifestations as descriptors instead.
This is a useful reminder that terminology continues to evolve even after an older word such as absence has become established.
Why ‘petit mal’ is no longer preferred
The term survives in historical writing and is still understood by some clinicians and patients.
But it is no longer preferred as formal terminology.
There are several reasons.
It is imprecise.
It can wrongly imply that the seizure is insignificant.
It can blur different seizure types.
And it belongs to a classification system based heavily on outward severity rather than modern electroclinical understanding.
Current terminology uses the specific absence seizure type or syndrome name instead.
‘Small’ seizures were never necessarily small in impact
The historical word petit encouraged an assumption that absence seizures were mild because they were brief and non-convulsive.
But repeated absences can interrupt attention, learning, conversation and memory throughout the day.
Some children experience many seizures daily.
Later research also challenged the idea that absence epilepsies are automatically harmless or cognitively neutral.
This change in understanding is one reason modern terminology avoids defining seizure importance by dramatic appearance.
Hyperventilation enters the diagnostic story
Clinical practice eventually recognised that hyperventilation could provoke typical absence seizures and their associated generalised spike-and-wave discharges in susceptible patients.
This became a standard EEG activation method.
It further strengthened the electroclinical identity of typical absence epilepsy because a brief behavioural arrest could be observed at the same moment as a characteristic EEG discharge.
Modern reviews continue to identify hyperventilation as an important activation procedure in absence epilepsy.
The classic ‘3-Hz’ description needs nuance
Typical absence seizures are historically associated with approximately 3-Hz generalised spike-and-wave.
That shorthand remains useful, but modern syndrome definitions recognise a wider frequency range in some contexts.
For example, current ILAE criteria for juvenile absence epilepsy allow generalised spike-and-wave frequencies extending above the classic 3-Hz value.
This shows how an iconic historical EEG finding can remain valid without becoming an inflexible rule.
Why history matters for modern terminology
Older medical records may use petit mal, pyknolepsy, minor epilepsy, epilepsia mitior or absence.
Those terms are not interchangeable automatically.
A historian or clinician reading an old case must ask what the author meant in that particular period.
A nineteenth-century ‘petit mal’ diagnosis cannot simply be translated into childhood absence epilepsy without additional evidence.
The language changed because the concepts changed.
The central historical lesson
The story of absence epilepsy terminology is the story of medicine learning to take subtle seizures seriously.
At first, brief lapses were defined mainly by how small they looked compared with convulsions.
Then clinicians described them more carefully.
EEG revealed characteristic electrical patterns.
Different absence types and syndromes were separated.
International classification gradually replaced petit mal with more precise terminology.
The modern word absence therefore carries centuries of changing observation behind it.
Sources and further reading
A brief history of typical absence seizures — Petit mal revisited. Epilepsy & Behavior. 2018.
Hughes JR. Absence seizures: a review of recent reports with new concepts. Epilepsy & Behavior. 2009.
Petit mal epilepsy: a review and integration of recent information. Journal of Clinical Neurophysiology. 1986.
Evaluation of the International League Against Epilepsy 1981, 1989 and 2017 classifications. Epilepsia Open. 2022.
International League Against Epilepsy. Updated classification of epileptic seizures. 2025.
Beniczky S et al. Updated classification of epileptic seizures: Position paper of the International League Against Epilepsy. Epilepsia. 2025.
ILAE 2017 Classification of Seizure Types Checklist.
ILAE definition of the Idiopathic Generalized Epilepsy Syndromes. Epilepsia. 2022.
Historical evidence checked: September 2026.