-
http://exhibits.library.stonybrook.edu/mfp/files/original/c779b264e0ba3e779d39ff5db1a0879e.pdf
d5ea2d1f830983dbe61a4c62d8e73b61
PDF Text
Text
Significance of Individual Variability in
EEG
Response
to Electroshock
Martin A. Green,
From
M. D.
the Department of ExPerimental Psychiatry, Hillside Hospital,
Glen Oaks, N.
10-11-57
"r
.50
�Significance of Individual Variability in
EEG
The assumption
Response
to Electroshock
is often tacitly
made
in studies of nervous system
function that the capacity for neurophysiological change is similar for animals
or humans in the groups under study. Differences in response are ascribed to
different parameters of the stimulus or to differences in the location and extent of lesions, either spontaneous or experimentally produced.
tion
may
Such an assump»
Perhaps another factor in the
not be warranted, however.
variability
of response under these conditions is an individual variability in neurophysio—
logical reactivity or responsiveness.
The
initial "base-line"
may
not be similar
in all individuals.
The
possibility of different inherent patterns of reactivity has
suggested by the studies of the alterations in the
have been impressed by the high degree of
EEG
been
during electroshock.
variability in
such
We
alterations both
in their quantitative and qualitative aspects. Although this variability has
been described by previous
investigators,
it
has not been stressed sufficiently;
nor have possible explanations been advanced or systematically investigated.
present report concerns a description of the changes in the EEG
Hillside Hospital
during electroshock in the/' material. The concept of neurophysiological
The
reactivity is presented
and studies
that
may
clarify this
problem are suggested.
�MATERIAL AND METHODS:
Eighty-nine patients
were
studied.
The
patients
who
received electroshock for psychiatric illness
Hillside Hospital and
were voluntary admissions to
the majority had not received electroshock previously.
The
diagnostic groups
and
schizophrenia.
psychosis
manic~depressive
included psychotic depression,
The
largest group
was
patients with depression.
Agesranged from 20
to
68 years,
with a median of #7 years.
Treatments were given three times weekly, each patient receiving at
least
12
treatments.
The Medcraft
instrument (alternating current) was used
61
for
current)
for 28 patients and the Reiter instrument (unidirectional
patients.
Electroencephalograms were taken prior to,
and two weeks following the course of treatment.
EEG
was abnormal were
to
36
weekly
Patients
specifically excluded from study.
2h
(from
day
non-treatment
a
an
at
whose
intervals during,
pre-treatment
Tracings were done on
hours following the previous treatment) with
eight channel Medcraft machine using needle electrodes.
Frontal, motor,
and
earlobe
vertex
temporal,
posterior
temporal,
anterior
parietal, occipital,
placements were employed with scalp
to scalp
and scalp
to earlobe combinations.
�RESULTS :
I. Delta Activity.
A.
Quantitative Differences:
delta activity
The
to the method described by Fink and
(8).
Kahn
The
was analyzed
according
duration of burst activity,
the lowest frequency, the average delta index in several leads, the highest
measured.
were
lead
one
in
time
delta
and
the
percent
highest
amplitude,
Re—
cords were classified as showing a low, middle or high degree of delta activity
(Fig. 1) according to
criteria previously described (8).
All patients developed delta activity during the course of
but differences in the amount of the slow activity and
were very apparent (Table
I).
Some
early in treatment whereas other
even
after
serial
12
EEG's.
not develop in
treatments.
As
treatments
of development
patients developed "high delta activity"
patients
showed only "low" or "middle" changes
latter patients
were followed
further with
treatment was continued, a high degree of delta activity did
some
of these patients
until
on
a daily basis.
This individual
variability in
treatments were given
change.
These
its rate
12
20 or more
They were
EEG
treatments, or until
resistant to neurophysiologic
response was independent of the type
of electroshock current employed, being present both with
unidirecticnal current applications.
alternating and with
�- h TABLE
Degree of Delta
I
Activity in Serial Electroencephalograms
during Electroshock
(2-n records were taken for each patient)
No.
Activity
EEG
No
change
delta activity
Low
Middle
High
B.
may be
ity.
-
EST 1
delta activity
delta activity
of Records in Each Treatment Period
u
L:..§
3
l
37
21
7
3
20
22
10
1
28
#5
25
1
16
amount
of
delta
the
activity
Although
total
Differences:
Qualitative
activ~
and
of
delta
voltage
to
frequency
records
as
differ
type,
similar,
One
prominent qualitative difference
during a course of 12 treatments.
is in the form of bursts which
as treatments are continued.
is the ratio of irregular delta
In some patients the
become more
The
show
burst activity
initial delta
change
frequent, slower and of higher voltage
irregular delta activity in such records is
less prominent and usually occurs at faster frequencies. In other patients
the reverse occurs.
form.
12
0
5
activity to bursts of slow activity. Nearly all records
much
-
10
Although burst
Delta activity appears chiefly in an irregular and scattered
activity is also present,
third group of patients the
amounts of
it is
not conspicuous.
irregular delta
and
In a
bursts are approx-
imately equal (Fig. 2).
These differences in the form
that the delta activity
assumes
is usually
constant during the course of treatment. At times, however, burst activity will
�.
become more prominent
-
5
than the irregular delta only during the
latter part
of
the course of treatment; or burst activity which appears prominent early in
treatment
may be overshadowed and
obscured in
later records
by a large amount
of continuous irregular delta activity.
The slow
activity is
maximal
electrodes and less pronounced at the
at the anterior temporal
more
frontal
and
posterior electrodes. Often
asymmetric, being of higher voltage, slower, and in greater amounts
anterior temporal
Only
and
frontal electrodes as
asymmetry occurs during treatment both with
is
at the left
to the right (Fig. 2).
compared
rarely is the reverse true, i.e. accentuation
it
on
the right side. This
alternating
and with
unidirectional
currents.
Another type of abnormality, though an infrequent one,
of rhythmic runs of delta activity which
(Fig. 2).
The
may
continue for
10
is the
to 20 seconds
regularity of the frequency and voltage of the slow
these runs is very striking.
appearance
waves in
These runs are usually infrequent, but may be
the most prominent alteration in the record.
In many records the amount of delta activity fluctuates during the
tracing. At times,
some
in other parts of the
This variation
II.
is
portions of a record
same
may
appear nearly normal, while
record the delta activity
may be
quite pronounced.
independent of the electrode combinations employed.
Spike or Spike-Wave Activity:
A
large number of records
or high voltage.
Most
show
single spike activity of low, moderate
often such spikes are slower and not as prominent as
�- 6 -
those present in patients with seizure disorders.
show spikenwave
A
small number of records
activity. This is usually at irregular,
mixed frequencies
and, again, does not resemble the regular rhythmic bursts commonly seen in
patients with seizure disorders (Fig. 2).
III.
Alpha Activity:
The
alpha activity
shows changes both
in
amount and frequency.
As
the amount of delta activity increases the amount of alpha activity usually
decreases. Changes in frequency occur but are not pronounced.
will
be slowed by 1-2 cps but
tracing. In a small
number
at times will remain the
same
The
frequency
as in the pre-ECT
of patients the amount and voltage of alpha activity
increases during treatment. This change persists during the post-treatment
period after the slow-wave activity subsides (Fig. 3).
IV.
Beta Activity:
The
fact that
activity in the
EEG
many
and the
induce
fast
barbiturates,
particularly
sedatives,
of
administration
the
in
controlling
difficulty
these drugs in this population studied makes
during the course of treatment.
are minimal.
activity.
The most
it difficult
to evaluate changes
In most instances changes in fast activity
frequent change,
when
present, is a decrease in the
�Discussion:
is that of the individual variability in the
As
EEG
described,
electroshock
therapy.
and
of
during
alteration
degree
type
and
of
rate
slow-wave
amount
of
its
the
activity
manifested
in: l)
this is
(amount
slow-wave
the
in
activity
differences
2)
development;
qualitative
The problem
being raised
of burst activity vs irregular delta activity, symmetry, fluctuating appearof
3)
slow
activity);
of
presence
rhythmic
slow
of
runs
ance
activity,
Spike or
spike-z-rave
activity;
and
LL)
changes in alpha and beta
Previous investigations (2, h, 5, 10,
have
ll,
activity.
12, 1h, 17, 18, 19, 20, 25)
stressed possible correlations with age , sex, frequency of treatment,
and
clinical change.
diagnosis,
employed,
of
current
psychiatric
type
Increasin" the frequency of treatment, for example, will increase the degree
of similar sex, age and
the
with
same
the
frequency
treatments
at
given
are
psychiatric diagnosis
same type of electroshock current, variability in the rate of development
of alteration in the
EEG.
However, when "ratients
their type anc‘. degree are still very prominent.
One explanation for this variability might be the distribution of the
electroshock current in the brain. Perhaps minor differences in the resistance
of changes in the
EEG
and
and
blooc‘
vessels
of
the
distribution
of the skull, in
their penneability or
taken
the
pathways
in
differences
create
of
tracts
nerve
in the arrangement
the
of
brain
portions
different
such
Unler
circmnstances,
the
current.
by
may
receive more or less current in
one
patient as
compared
to another.
variously
these
by
generated
of
the
electrical
activity
Differences in
type
affected areas might account for variability in the
EEG.
Available studies employing direct intracerebral measurements indicate
considerable diffusion of current throughout the brain (6, 9, 16, 21).
�However, a
concentration of current anteriorly and along: large neuronal
pathways, such as the corpus callosmn, has been demonstrated.
No
further
infon'ration is available as to amounts of current received. by more Specific
cerebral areas.
Due
to the high resistance of the skull only a small portion of the
applied. current actually reaches the brain.
The amount of
current entering
different portions of the brain is said to be determined by the resistance
of the skull overlying these areas; the anterior concentration of current
being; the result of the thinness of the temporal bone with its consequent
lower resistance as compared to other parts of the skull (9, 21).
Several considerations, however, indicate that individual differences
in these factors of resistance
and amount of
areas of the brain are of minor,
during-g
electroshock.
It is
if
current reaching,- different
any, importance in the
ELG
response
the occurrence of the generalized seizure
291'.
§_e_,
rather than the passage of electricity, which is the primary factor. During
a course of grand-mall therapy induced by non-electrical means such as
metrazol,
EEG
changes occur which are similar,
with electroshock (13, 1h). Diffuse slow-wave
in general, to those seen
activity, accentuated
of
The
amount
described.
are
activity
anteriorly,
slow—wave activity increases during treatment but shows individual variability
unrelated; to the n unber of treatments. Another observation is that electroand 81‘.de
or spike-wave
shock therapy nhich induces
petit-mal (7, 18) or focal (3) seizures rather
than grand-mal, does not produce the characteristic build-up of slow-wave
activity. In addition, there is no increase in the degree of delta activity
in our patients in whom grand-mal tae rapy is given with high suprathreshold
stimuli as compared to those in whom threaiold stimuli are used.
�-9-
.
Factors of current cannot be entirely dismissed, however. Even with
grand mal therapy, the type of current employed may influence the
we haVe
EEG
change.
confirmed a previous study (20) showing that the rate of increase
of delta activity
is
slower in therapy with unidirectional current than in
that with alternating current. Similarly, brief stimulus therapy is said to
produce smaller degrees of
alteration in the
EEG
as compared to alternating
current therapy (15).
The
EEG
other theory to
be
considered in explaining the variability in
re5ponsiveness, and the one which
is
probably more determinant, involves
inherent differences in neurophysiological reactivity.
By
this is
meant
both the quantitative and qualitative aspects of the inherent capacity of
the nervous system to respond to stimuli or injury. Not only the degree of
response, but also the type of response,
type and degree of
EEG
may have
these determinants.
The
abnormalities developed during electroshock therapy
appear to be the reflection of such inherent individual differences in
neurophysiological reactivity.
Several types of investigation
Methods
other than electroshock
may
known
serve to
to produce
test this hypothesis.
EEG
alterations could
be
applied prior to treatment. These might include lowering the blood sugar
by
parenteral insulin, intravenous administration of convulsants such as
metrazol or Hegimide, photic stimulation, or the intravenous administration
of drugs such as barbiturate.
In addition, perhaps the actual electroshock
seizure flzreshold or the pattern 0: severity of the seizures
measure of nervous system responsiveness.
Data from such
could be correlated with the degree an? types of
shock.
In this manner
it might be
ELG
may be a
investigations
change during
electro-
possible to demonstrate different patterns
�410-
classify individuals accordingly.
not only help in understanding the variability in
reactivity
of neurophysiological
Such
studies
may
and
alterations during electroshock but would have wider application
to other problems in clinical electroencephalography and neurology. For
example, tie basis for the development of Spontaneous seizures secondary
the
EEG
to traumatic, vascular, or neoplastic lesions of the nervous system
known. Patients with lesions comparable in type, size and location
or
may
not develop seizures.
As
previously described,
spike or Spike-wave activity during electroshock.
difference in
not
may
subjects
some
show
This suggests an inherent
clinical seizures or
he capacity to develop
is
EEG
seizure
is
reflected in
the
whether
the
to
injury
nervous
system,
"injury"
following
activity
spontaneous or induced. Differences in this capacity may be
varying patterns of neurophysiological reactivity.
Differences in neurophysiological reactivity
in the pre-troatment
abnormal
(ll),
EEG.
Patients in
whom
"instabile" (22), or axons
may
also
be
manifested
the pre-treatment record is
a predominant alpha rhythm (S)
LEG
the
in
during electroshock.
the
alteration
to
said
develop
greatest
are
Other investigators have not confirmed these observations (2, 23). Actually,
such
correlations
depend on the method of
analysis of the pre-treatment
criteria used for "abnormality." Further investigation of this relationship is necessary.
Suggesting that neurophysiological reactivity is an inherent process
does not imply that a physiological basis does not exist or cannot be in-
record employed and the
vestigated. This
may
reside in the central nervous system
itself, consisting
of individual differences in neurochemical systems or in the permeability of
cells-or blood vessels; or
it
may be
outside the nervous system. Individual
�‘11-
differences in hormonal or other humeral substances produced during the
stress of electrosho
k may
serve to "sensitize" or "desensitize" the
cerebrum with regard to developing
ical activity. That such factors
following studies.
Trypan red
different
may be
amounts and types of
electr-
operative is suggested by the
injected intraperitoneally in cats before
a course of electroshock decreased the permeability of the blood~brain
barrier
and reduced the degree of
EEG
changes as compared to control
animals (1). Atropine and scopolamine adminstered during a course of
electnodiock in
man
blocked the development of the usual slowawave activity
(2h).
Electroshock therapy affords an excellent opportunity for the experimental investigation of the problem of an inherent neurophysiological
reactivity.
animals.
The
One
is able to
apply studies directly to man, rather than
stimulus to the central nervous system can be standardized
and the degree of neurophysiological change
changing different parameters.
controlled, within limits, by
Tests of 336 responsivity can be given before
such dianges are induced as well as during and
after treahnent.
Re-study of
patients is often possible then subsequent courses of treatment are necessary.
�.12..
marl:
l. Indiviéual
EEG
the
in
qualitative,
changes during a course of electroshock treatment in 89 patients are
éifferences, both quantitative
and
described.
2. These differences are pronounced
and
are not explainable by age, sex,
type of shock current, frequency of treatment, psychiatric diagnosis,
or clinical change.
3.
An
inherent capacity for neurophysiological change that has both quan-
titative
and
qualitative aSpects
may be
the primary determinant of these
differences.
h. Variation in skull resistance and in the amount of current reaching
the brain aspear to be minor factors.
5. Investigations that might serve to
described. Such studies
may
test
the hypothesis presented are
lead eventually to a classification of
individuals as to different patterns of neurophysiological reactivity
and
clarify other problems in clinical neurology
and electroencephalography.
�é 13 -
REFERENCES
l.
Aird, R.B.,
Strait,
(1956):
S.C.
and
Bowditch,
M.K.,
Hrenoff,
L.A., Pace, J.w.,
Current Pathway and Neurophysiological Effects of Electri-
J.
cally Induced Convulsions.
Nerv.
Ment.
&
Dis., igg:
Bagchi, B.K., Howell, R.W. and Schmale, H.T. (l9h5):
alographic and
The
J. Pszchiat., lgg: h9-61.
Am.
R.
(1953):
and
S.
Feinstein,
Berg,
Impastato,
D.J.,
P.S.,
Bergman,
Electroencephalographic Changes Following
Focal Seizures, Conf. Neurol.hl§:
Electroshock,
EEG.
Chusid, J.G. and Pacella, B.L. (1952):
Electric
271-277.
Clin. Neurgghxs., g:
Shock Therapies,
J.
Electrically Induced
Slow Wave Phenomena
Callaway, E. and Boucher, F. (1950):
157~162.
Neuro. Ment.
H.
Dis., llé‘
(1953):
shock on the Cortical and Intracerebral
shock Process,
M.
J. Nerv.
and Kahn, B.L.:
&
Response in Electroshock:
Arch. Neurol.
Hayes, K.J. (1950):
Arch. Neurol.
&
The
&
95—107.
Electroactivity of the
l3:
287-29h.
Experimental Studies of the Electro-
Ment. Dis.
Relation of
in
Effects of Electrou
Brain in Schizophrenic Patients, Conf. Neurol.,
M., Kabn, B.L. and Green, MLA.:
in Intensive
The Electroencephalogram
Delgado, J.M.R., Alexander, L. and Hamlin,
Fink,
Electroenceph-
Clinical Effects of Electrically Induced Convulsions
in the Treatment of Mental Disorders.
Fink,
505-512.
EEG
(in press).
Delta Activity to Behavioral
Quantitative Serial Studies, A.M.A.,
Pszphiat. (in press).
Current Path in Electric Convulsion Shock,
Psxchiat., §§: 102-109.
�-1hREFERENCES
10.
LC. and Pincus,
Hoagland, IL, Malamud, w., Kaufman,
G.
(19%):
in the Electroencephalogram and in the Excretion of
17
Changes
Ketosteroids
Accompanying Electroshock Therapy of Agitated Depression, Psychosom.
Med. , 8:
11.
216-251.
Kennard, M.A. and Willner, MD (1908):
Electroencephalogram
M.
lg:
13.
Serial
(1955):
Results from Shock Therapy,
4AM
ho-hs.
P83111835” £02:
Igtz,
Which
Significance of Changes in the
Changes Due
to Electrotherapy, Dis. Nerv. $35.,
120-122.
Knott, G.R., Gottlieb,
J.S.,
Leet, Hull and Hadley, H.D.
Jr.,
(1943):
Changes in Electroencephalograph Following Metrazol Shock Therapy:
A
1h.
Quantitative Study, Arch. Neurol.
8c
Psychiat., 29: 529-53h.
Levy, N.A., Serota, mm and Grinker, R.R. (19142):
Disturbance in Brain
Function Following Convulsive Shock Therapy, Arch.Neurol.
PsEhiat.,
fl:
Liberson, wur. (1951):
1009-1027.
Current Evaluation of Electric Convulsive Therapy,
Mento
ASS.
Nerv.
PUbl.
R93.
D180,
0... nun-U.
Lorimer, F.M., Segal,
&
M.M.
and
Stein, S.A.
2:
199-2310
(19149):
Path of Current
Distribution in Brain During Electroconvulsive Therapy,
EEG.
17.
Clin. Neurophysiol.,
3;:
318-3148.
Moriarity, J .D. and Siemens, J .0. (19M): Electroencephalographic Study
of Electric
Shock Therapy, Arch. Neurol.
&
Psychiat., 21: 712-718.
�- 15 REFERENCES
18.
Pacella, B.L., Barrera,
S.W. and Kalinowsky, L.
(l9h2): Variations in
of
Shock
Therapy
with
Electric
Electrocephalogram.Associated
the
Patients with Mental Disorders, Arch. Neurol.
&
Pszchiat., 51:
367—381l-
19.
Proctor,
J.E. (l9h5): Clinical and Electra-physiological
L.D. and Goodwin,
Observations Following Electroshock, Amer. J. Pszghiat., 39;:
707-800.
20.
Proctor,
L.D. and Goodwin,
J.E. (l9h3): Comparative Electroencephalographic
Observations Following Electroshock Therapy using
Alternating and Unidirectional Fluctuating Current,
22:
21.
Raw 60
Am.
Cycle
J. Pszghiat.,
525-530.
Smith, J.w. and Wegener, C.F. (19hh):
On
Electric Convulsive Therapy with
Control???
Electrodes
of
Application
Parietal
to
a
Particular Regard
Neurol.,
et
Acta
Measurements,
Pszchiat.
Voltage
Intracerebral
by
lg:
529-5h9.
Sulzbach, W., Tillotson, K.J., Guillemin,
(l9h3):
A
Consideration of
Some
V.
Jr.
and Sutherland, G.F.
Experience with Electric Shock
Various
to
Regard
with
Special
Mental
Diseases,
Treatment in
Psychosomatic Phenomena and to Certain Electro~technical Factors,
23.
Taylor,
R.M. and
Pacella, B.L. (19h8):
The
Significance of Abnormal
Electroencephalograms Prior to Electroconvulsive Therapy,
J.
Nerv.
&
Ment.
Dis., 291: 220-227.
�.
16
-
REFERENCES
2h.
Ulett,
G.A. and Johnson, M.W. (1957):
Upon
Electroencephalographic Changes Induced by Electro-convulsive
Therapy,
25.
W911, A.A. and
EEG.
Olin. Negggghxsiol.,.2: 217-22h.
Brinegar, wgc. (19h7):
Following Electric
21:
Effect of Atropine and Scopolamine
719-729.
Electroencephalographic Studies
Shock Therapy, Arch. Naurol.
&
Pszghiat.,
�
Dublin Core
The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/.
Title
A name given to the resource
Research Files and Unpublished Works
Dublin Core
The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/.
Title
A name given to the resource
Martin A. Green: Significance of Individual Variability in EEG Response to Electroshock, 1957
Type
The nature or genre of the resource
Text
Identifier
An unambiguous reference to the resource within a given context
mfp-03-01-002-10-010
Date
A point or period of time associated with an event in the lifecycle of the resource
1957
Creator
An entity primarily responsible for making the resource
Green, Martin A.
Subject
The topic of the resource
<a href="http://id.loc.gov/authorities/subjects/sh85113021">Research Files</a> and Unpublished Works -- Hillside Hospital, Glen Oaks, NY, 1953-1965
Relation
A related resource
The Max Fink Collection
Description
An account of the resource
Research papers, files, and related correspondence
Rights
Information about rights held in and over the resource
<a title="IN COPYRIGHT - EDUCATIONAL USE PERMITTED" href="http://rightsstatements.org/vocab/InC-EDU/1.0/" target="_blank">IN COPYRIGHT - EDUCATIONAL USE PERMITTED</a>
Source
A related resource from which the described resource is derived
Special Collections and University Archives, University Libraries. Stony Brook University Libraries (State University of New York).
Language
A language of the resource
en-US
Format
The file format, physical medium, or dimensions of the resource
application/pdf
Publisher
An entity responsible for making the resource available
Contributor
An entity responsible for making contributions to the resource
Research