Letters to the Editor
Epileptic aura and qualitative alterations of consciousness in focal
seizures: A neuropsychiatric approach
To the Editor:
Over thirty years ago, two eminent specialists published a book
with the poignant title The Bridge between Neurology and Psychiatry
[1]. They defended the necessity of a good communication between
the two neurosciences, since they share many aspects, including the
object of study i.e. the brain. Unfortunately, the poor communication
between the two specialities continues, resulting in the persistence of
some misconceptions about epilepsy [2]. Specifically, we believe that
some puzzling questions on epilepsy and consciousness could be bet-
ter solved by sharing the relevant knowledge from both specialities.
The 1981 classification of seizures of the International League
Against Epilepsy (ILAE) distinguished two kinds of partial seizures:
simple partial seizures (SPSs) and complex partial seizures (CPSs).
This separation was based on the assessment of consciousness during
seizures: preserved in SPSs and impaired or even abolished in CPSs.
The problem of this classification stemmed from the concept of con-
sciousness used by ILAE: this definition focussed on the quantitative
or objective side of consciousness (responsiveness, a measure of
arousal), thus neglecting its subjective or qualitative side (awareness
of consciousness contents).
This definition of epileptic consciousness in epilepsy did not
escape criticism [3], including recommendations to replace the term
“partial” with “focal” and to no longer use the terms simple and
complex as seizure descriptors [4]. Finally, in the recently published
Revised Terminology and Concepts for Organization of the Epilepsies
of the ILAE Commission on Classification and Terminology, the
distinction between the different types of focal seizures (e.g., complex
partial and simple partial) is eliminated. The arguments in support of
this position are that it is impossible to scientifically define conscious-
ness and that the necessary information to create a scientific classifica-
tion within focal seizures based on consciousness is just not available
at the present stage [5]. However, the problem persists because the
current ILAE proposal uses the same concept of consciousness to
describe the different types of focal seizures, specifically:
• Without impairment of consciousness/responsiveness:
○ With observable motor or autonomic components (roughly
corresponds to the concept of simple partial seizure).
○ Involving subjective sensory or psychic phenomena only
(corresponds to the concept of aura, as endorsed in the 2001
ILAE Glossary [4]).
• With impairment of consciousness/responsiveness (roughly corre-
sponds to the concept of complex partial seizure).
• Evolving to a bilateral, convulsive seizure (involving tonic, clonic or
tonic–clonic components); replaces the term “secondarilygeneralized
seizure”
.
Over the last few years, epileptologists have been working on a
bi-dimensional (level-versus-contents) model of consciousness in
epilepsy [6–8]. These investigations represent an important effort to
identify brain networks and mechanisms involved in ictal alterations
of consciousness. Moreover, some authors have developed psycho-
metric instruments to evaluate the contents of consciousness in
epileptic seizures, such as the Ictal Consciousness Inventory [9] and
the Phenomenology of Consciousness Inventory [10,11]. Despite their
potential clinical applications, these scales are used to capture quali-
tative aspects of consciousness (experiential phenomena) only in
seizures involving sensorial and psychic productions, thus failing to
provide any useful information about alterations in the contents of
consciousness related to motor and autonomic seizures.
According to these models, patients with autonomic or motor
seizures do not have any experiential modification in their conscious
state, as the behavioral manifestations of their seizures are not ac-
companied by any qualitative change of consciousness. For example,
in an autonomic seizure with hot flushes or in a motor seizure with
automatic emission of words, patients would remain in their usual
state of consciousness, without being affected by these autonomic
or behavioral reactions. Such an interpretation does not match with
clinical observations and patients' reports. A possible solution to this
conundrum can be found by addressing some misconceptions on
the concept of epileptic aura.
In the Terminology and Concepts for Organization of the Epilep-
sies of the ILAE Commission on Classification and Terminology [5],
the epileptic aura is present only in sensory and psychic focal
seizures; in fact, aura is synonymous with focal seizures involving
sensory or psychic phenomena. Accordingly, in focal seizures with
motor or sensory manifestations, there is no aura.
The concept of aura was completely different for classical authors,
neurologists and psychiatrists alike, who interpreted aura as a psychic
experience indicating that the focal seizure had begun and therefore,
the normal conscious state had been replaced by epileptic conscious-
ness [12–14]. Kinnier Wilson expressed this concept of aura in the
following terms: “The aura is nothing else than the first conscious in-
dication of the commencement of a process that is about [to] exterior-
ize itself by signs of the physical series, though it belongs to the
psychical series” [12]. According to this concept, the epileptic aura is
the specific state of consciousness, which indicates the beginning of
a focal seizure. The psychic manifestations of the aura are present in
all types of seizures and are independent from and different to the
contents of each individual seizure, either motor or autonomic or sen-
sorial or psychic.
Furthermore, Henry Ey's forgotten study on the phenomenology
of aura shed light on the following six characteristic features defining
aura [14,15]:
1) Suddenness: this phenomenon always begins suddenly and
unexpectedly.
2) Timeless nature: the events occurring during the discharge seem
to take place outside time, since the patient is usually unable to
correctly estimate their duration.
3) Passiveness of will: the subject cannot stop or modify the seizure
manifestations, but only observe them as an astonished spectator.
Epilepsy & Behavior 23 (2012) 512–513
1525-5050/$ – see front matter © 2012 Elsevier Inc. All rights reserved.
doi:10.1016/j.yebeh.2011.11.031
Contents lists available at SciVerse ScienceDirect
Epilepsy & Behavior
journal homepage: www.elsevier.com/locate/yebeh