Possible Temporal Lobe Symptoms
VERNON M NEPPE MD, PhD(Med)
Seizure disorders with behavioral disturbance,
may initially be interpreted as psychiatric in origin.
Many such problems relate to the temporal lobe of
the brain. The features of temporal lobe epilepsy
and non-epileptic dysfunction of the temporal lobe
are so varied and so protean that it is necessary
to classify them. I have suggested the term "Possible
temporal lobe symptoms" (PTLSs) relate to features
which can be induced by stimulating areas of the temporal
lobe during neurosurgery. These symptoms only become
specific symptoms of temporal lobe dysfunction if
their occurrence is validated empirically during a
seizure - either through observation or by the electroencephalogram
(hence the word "possible" in possible temporal lobe
seizures). Great care must be taken in interpretation
of such features : For example, using a phenomenological
analysis, I demonstrated that the symptom of deja
vu commonly regarded as symptomatic of temporal lobe
epilepsy indeed had a very special phenomenologic
quality in patients with temporal lobe epilepsy.
Like many other such focal symptoms, this involves
its association with post-ictal features such
as sleepiness, headache and clouded consciousness
and its link in time with these features. This association
provides an excellent clue to the existence of temporal
lobe epilepsy. However, deja vu is a normal phenomenon
occurring in 70 percent of the population and unless
such phenomenological detail is obtained, patients'
symptomatology may be misinterpreted. I similarly
studied olfactory hallucinations but a specific type
of temporal lobe epilepsy olfactory hallucination
could not be demonstrated although there were suggestive
features. A major message, therefore, may be the
relevance of adequately assessing the symptomatology
of patients presenting with epilepsy. It may be that
this is a direction as relevant as electroencephalographic
monitoring. Most of all it reminds us how slender
our interpretations of other related but different
symptoms such as "he experiences strange smells" might
be and the fact that it is critical to elicit whether
these are episodic in quality and linked with other
symptomatology particularly epileptic or temporal
lobe. A written test instrument designed to screen
for such symptoms which I use in clinical practice
is the INSET -
The INVENTORY OF NEPPE OF SYMPTOMS OF EPILEPSY
AND THE TEMPORAL LOBE (INSET). The INSET involves
screening for possible temporal lobe, epileptic and
organic symptoms and spells. Thereafter the symptoms
are categorized into several headers namely nonspecific
symptoms, possible and controversial temporal lobe
symptoms, seizure related and other focal features.
The test is based on the subject and / or his family
responding to questions which are thereafter elaborated
in greater clinical detail. Responses are at two time
levels: current as well as the most common frequency
in the remote past and require the patient to rank
frequency from never through less than yearly to more
than daily (i.e. 0-6). Questions in the INSET have
been based on the earlier Neppe Temporal Lobe Questionnaire
which itself derived from an intensive literature
review on the topic. The INSET plus medical history
is a major determining factor for whether to order
follow-up specialized electroencephalograms such as
ambulatory EEG.
TABLE: POSSIBLE TEMPORAL LOBE SYMPTOMS
(PTLSs)
Controversial PTLSs (CPTLSs)
- severe hypergraphia
- severe hyperreligiosity
- polymodal hallucinatory experience Paroxysmal
(Recurrent) Episodes of:
- profound mood changes within hours
- frequent subjective paranormal experiences e.g.
telepathy, mediumistic trance, writing automatisms,
visualization of presences or of lights/colors
round people, dream ESP, out-of body experiences,
alleged healing abilities
- intense libidinal change
- Uncontrolled, lowly precipitated, directed,
non-amnesic aggressive episodes;
- recurrent nightmares of stereotyped kind
- episodes of blurred vision or diplopia
Not Necessarily Disintegrative PTLSs
(NPTLSs)
Symptoms Not Necessarily Requiring Treatment
Paroxysmal (Recurrent) Episodes of:
- Complex visual hallucinations linked to other
qualities of perception such as voices, emotions,
or time
Any form of:
-
Auditory perceptual abnormality;
-
Olfactory hallucinations;
-
Gustatory hallucinations;
-
Rotation or disequilibrium feelings
linked to other perceptual qualities;
-
Unexplained "sinking," "rising,"
or "gripping" epigastric sensations;
-
Flashbacks;
-
Illusions of distance, size (micropsia,
macroscopy), (micropsia), loudness, tempo, strangeness,
unreality, fear, sorrow;
-
Hallucinations of indescribable
modality.
-
Temporal lobe epileptic deja vu
(has associated ictal or postictal features {headache,
sleepiness ,confusion} linked to the experience
in clear or altered consciousness )
-
Any CPTLSs which appear to improve
after administration of an anticonvulsant agent
such as carbamazepine.
Disintegrative PTLSs (DPTLSs)
Symptoms Requiring Treatment: Paroxysmal
(Recurrent) Episodes of:
- Epileptic amnesia;
- Lapses in consciousness;
- Conscious "confusion" ("clear" consciousness
but abnormal orientation, attention and behavior);
- Epileptic automatisms;
- Masticatory-salivatory episodes;
- Speech automatisms;
- "Fear which comes of itself" linked to other
disorders (hallucinatory or unusual autonomic)
;
- Uncontrolled, unprecipitated, undirected, amnesic
aggressive episodes;
- Superior quadrantic homonymous hemianopia;
- Receptive (Wernicke's) aphasia.
- Any CPTLSs or NPTLSs with ictal EEG correlates.
Seizure related features ( SZs )
Any typical absence, tonic or clonic
or tonic-clonic or bilateral myoclonic seizures in
the absence of metabolic, intoxication or withdrawal
related phenomena.
Clearly there is a greater need to
pay attention to unusual episodic symptoms. This will
ultimately lead to a workable classification and the
recognition that certain seizure like features need
be treated by psychiatrists.