Brit. J. Psjchiat. (i97@), 127, 78—85
Models of Mania: An Individual By D. R. HEMSLEY
and H. C. PHILIPS
Summary A longitudinal study ofa single case ofmanic-depressive between @
ments
psychiatric
were
made
ratings, reaction on
9 occasions
Case Study
psychosis investigated the relationship
time and two measures
over
a five-month
period.
of autonomic The
number
activity. of slow
Measure
responses
on
the reaction time task increased with increasing depression. Manic periods appeared not to be characterized by a slowing of responses, but rather by an increase in the number of premature responses,
i.e.
those
made
to the
warning
signal.
A derived
performance
index
discriminated
over the complete range from severe depression to severe mania. Increased depression was associated with lower heart rate resting levels, and increasing mania with increased skin conductance levels. An increased frequency of slow reaction times was significantly associated with lower resting heart rate. Skin conductance measures ccrrelated significantly with the number of premature responses made on the reaction time tasks. Some differences in the relationships emerged when data obtained during the administration of lithium were included in the analysis. The results are discussed in relation to both the bipolar and the continuum models of manic-depressive psychosis. The latter model isnot supportedby thepresentinvestigation, sincemanic episodes were not characterized by a more severedeparturefrom normalitythan depressive
episodes
on either the number
of slowed
Irrri@oDuc'noN On the basis of clinical observations it would
findings
depressive psychosis. The prediction would be that variables reflecting changes in activation
(e.g.
1954;
ig@@). However,
Woodworth
and
it is possible
that
the
help
of
changes
in
psychophysiological
responses mediated by the autonomic nervous system and the central nervous system (Duffy,
level would show increments during mania and decrements during depression, the degree of mood shift affecting the clarity of this rela tionship. This hypothesis is consistent with a of the disorder
measures.
optimum levels of activation interact with task complexity to produce an ‘¿inverted U' relation ship between activation and reaction time. Activation levels may also be monitored with
with changes in mood state in cases of manic
view
or autonomic
(Teichner,
Schlosberg,
seem reasonable to hypothesize differences in the level of activation (or ‘¿arousal')correlated
bipolar
responses
1973).
Although
the
intercorrelations
between
these measures on a single occasion are not high (Lacey, 1956), it is well established that they are indicative of changes in activation (Duffy,
Silverman,
1969). Changes in activation or arousal might be monitored in various ways and it is not clear that such measurements all reflect a single
systems depends
arousal continuum.
problems of measurement, individualdiffer
It has been found that reaction time can be used to monitor activation level. Stimuli which
ences, homeostatic mechanisms, psychosis(Claridge,1967).
are known to affect the level of activation, e.g. drugs, fatigue and motivational differences,
Reaction time and manic depressive psychosis
have frequently been reported to influence reaction time, though there are some ambiguous
The relatively gross changes in behavioural activation found in manic-depressive psychosis
1973). The
78
degree of intercorrelation between
on a number
of factors, such as and
possibly
BY D. R. HEMSLEY
might show either a linear or an inverted U relationship with simple reaction time (Figure Ai, Bi). Court (1968, 1972) has proposed a third alternative, suggesting that the beha vioural manifestations of mania and depression
may be superficial and not necessarily of aetio logical significance. Court puts forward a continuum model of manic-depressive psychosis, with mania a more severe departure from normality
than
depression
(Figure
Ci,
Cii).
His arguments are based on clinical, biochemical and psychological data. Although he has brought together a mass of data, some of his conclusions seem faulty (Silverman, 1969). Simple reaction time has been shown to bear a close relationship to the degree of severity of illness and to changes in clinical state (Court, 1964; King, 1969). Court's model suggests that hypomanics
and
manics
should,
as a group,
be slower than normals and depressives. This was confirmed in his i@68 study which corn pared
normals
and
depressed
and
manic
patients on a simple reaction time task, with preparatory intervals ranging from i to i6 seconds. These resultswere criticized by Silverman (1969) on the ground that some of the depressed group had shown no manic episodes
and
might
therefore
have
been
suffering
from a genetically distinct form of depression (Winokur and Clayton, 196g). As Court him self points out, a study which remains to be carried
out to confirm
the continuum
model
measures and manic-depressive
H.
other
C. PHILIPS
79
data on psychophysiological
mediated
by
the
autonomic
responses
nervous
system
need to be considered. There appear to be no recent studies of the psychophysiology of manic depressive psychosis, but there is general agreement that in depression there is a signifi cant
reduction
in basal
sweat
gland
activity,
i.e. low skin conductance (S.C.) (Lader and Wing, 1969; Noble and Lader, 1971a). Re duced
spontaneous
fluctuations
were also rela
ted to retarded depression. Less clear-cut results have been found for the cardiovascular system.
Noble
and
rate unchanged pressed
patients,
Lader
(1971b)
found
pulse
after ECT in a group of de although
forearm
blood
flow
was found to be lower prior to ECT. Lader and Wing (1969), however, found a trend towards higher basal pulse rate in a group of retarded and agitated depressives, compared with nor mals, though
the difference
was significant
only
for the agitated depressives. Hence Court's model is not fully supported by the data from autonomically mediated responses, which are more consistent with bipolar models (Figures Mi, Bii). However, Court (1972) does accept the possibility of some
low arousal measures in mania and depression if Claridge's view (i 970) is correct and the psychoses are characterized by a dissociation of arousal measures. Only with data collected during
mania
can
the
issue
be further
clarified.
is
the repeated testing of a group of patients at differing pointsalongthecontinuum. Psychophysiological psychosis
AND
Aims of present study
The usefulness of the individual case study in psychological research has been discussed by Shapiro(1966).He has distinguished between the observation of particular detailed configura tions of behaviour and the observation of rela tionships between different kinds of phenomena. The present longitudinal study investigated the relationships between mood change, reaction
Court (1968, 1972) also draws on psycho physiological data from studies of skeletal muscleand EEG reactivity tosupporthismodel of manic-depressive psychosis (Whybrow and Mendels,1969).The latter authorshypothesize time and autonomic indices (Skin Conductance an unstable state of the central nervous system and Heart Rate) over a number of cycles in a leading to a disorganized hyper-reactivity in single case of manic-depressive psychosis. depression which iseven worse in mania. The Three possible sets of relationships were implication of this view is that there is a dis suggested by the literature, referred to from sociation of mood state, behavioural indices now on as A, B and C. C corresponds to of activation and psychophysiological measures. Court's continuum model, A and B represent The data they review on skeletal and C.N.S. variants of the bipolar model. The alternatives indices do in part support this view; however, are illustrated diagrammatically. Model A
8o
MODELS OF MANIA:
AN INDIVIDUAL
CASE STUDY
investigation between I.
is a pilot study of the relationship
these
variables
in
manic-depressive
psychosis. I!
METHOD
The subject The patient investigated was a 27-year-old man with a history of marked mood swings between depression and mania. The cycle had begun four
at A (ii)
FIG. A.
years previously following a suicidal attempt.
N
N
E 0@1
During
his depressive periods, he showed depressed mood; he occasionally felt suicidal, but was most charac teristically apathetic, retarded and extremely drowsy. When hypomanic he showed flight of ideas, elation, distractibility and constant restless movements. He
had no hallucinations or delusions, and his cognitive state was unimpaired. The swing between the two B (i)
moods was relatively
B (ii)
FIG. B.
periodicity
four
to
five
weeks.
showing During
a in
patient treatment at the Maudsley Hospital he was diagnosed manic-depressive psychosis—circulartype
I
(2963). Treatment had included antidepressants, pheno thiazines, lithium carbonate (‘Priadel'), haloperidol and ECT. No marked clinical improvement had been achieved, except with ECT. When a course of
m 0
H
tl
C (i)
ECT was given in a depressive phase it appeared to break the cycle for 2 to 3 months, during which time the patient appeared stabilized. The patient was first
C (i@
Fio. C. predicts normal
fast and reliable,
of about
that responses in mania, and
will be faster than slower in depression.
A similar relationship is predicted for auto nomic measures, i.e. arousal higher than normal in mania and lower during depression. Model B suggests that both depression and mania will result in slower responses
than normal,
but no
clear prediction is made as to the relative speeds in mania
and
depression.
Autonomic
indices
seen
during
such
a post-ECT
period.
At this time
both the psychiatrist and the patient himself felt that he was close to his own ‘¿normal' level. During
the
assessment
period
to be described,
the
patient was being given orphenadrine for a residual Parkinsonian
tremor,
night
sedation,
and
occasionally
haloperidol to control hypomanic episodes. Lithium was recommenced
during the last few weeks of this
study. Because of possible effects of this drug on the study, the results have been analysed both with and without those occasionswhen lithium was being taken.
are considered to relate to manic and depressive episodesas in Model A. Model C predicts Procedure reaction
time
in
mania
to
be
longer
than
reaction time in depression, which will itself be longer than reaction time in normality. Auto nomic measures should parallel these changes. The three models suggested do not represent all the possible relationships between the variables under consideration. The present * Court's
model
is not
explicit
in predicting
which
arousal measures might increase in depression and mania, and which might decrease. However, the measures are expected to deviate from normality in the same direction
for both depression and mania.
During a five-month period, the patient was seen on nineteen occasions, at which times mood ratings,
reaction time and psychophysiological data were collected. On three occasions during this period psychophysiological data could not be collected, so that only the two other measures were obtained. This loss was due to technical problems unrelated to
the patient's clinical state. On each occasion the patient completed the reaction time task. This was followed immediately by an assessment of the psycho physiological variables. The patient then had an interview
with
observer rating.
his psychiatrist,
who
completed
the
8r
BY D. R. HEMSLEY AND H. C. PHILIPS
variations
Measures
Ps,chiatric rating: The rating was on a 7-point scale: severely
depressed,
moderately
depressed,
slightly
ment
in activation.
followed
the
Psychophysiological
reaction
time
task
assess
immediately,
and involved a minimum of 15 minutes of seated
depressed, normal, slightly manic, moderately manic,
resting behaviour. After the electrodes to assess HR.
severely manic. This was as used by Coppen ci al. (@@7i). The rating was made independently on each
remain
occasion of testing by one of the authors and by the consultant psychiatrist in charge of the case. The
data was then recorded. An attempt was made to assess responsivity to tones by presenting a series of
inter-rater
reliability
of the scale (rank correlation
and S.C. had been attached, the patient was asked to as still as he could.
auditory
signals
(i,ooo
Ten
minutes
Hz, 85 Db,
of resting
i sec. duration)
in
coefficient) was 0 92 ; this was considered sufficiently
a sequence approximately 6o sees apart. However, a&
high for only one set of ratings
mentioned previously, phasic data proved impossible
subsequent
analysis
to be used in the
to assess. On two occasions the patient pulled off his
of the data.
Although the selection ofthis case was influenced by the relatively unambiguous periods of mania, nor mality and depression, it can be argued that the use
of two unipolar scales for depression and mania would have been more appropriate to allow for the recording of mixed clinical states. Reactiontime: The task was a simple reaction time experiment with a light as a signal. The warning signal was a tone delivered through headphones. The preparatory interval varied from 50 m.secs to 95°m.secs. Inter-trial intervals ranged from 5 to 9
electrodes and period. Sweat gland
headphones activity
during
the
recording
was assessed by utilizing
silver-silver-chloride electrodes attached to the palmar aspect of two fingers on one hand, and recording
resistance on a Grass polygraph throughout.
skin
The data.
were sampled at onset and at the end of the ten minutes of basal activity. These scores were then converted
into log skin conductance
scores were obtained
skin conductance
in each
units. Thus two
session.
fluctuations
The number
were
of
also counted
seconds. Each session consisted of , io trials. There was a reaction time ceiling of45o m.sec. built into the
during the first minute and the last minute of the
apparatus;
tion was that used by Lader and Wing (1966). H.R. was assessed by means of a plethysmo-@
the measure
of slowness taken
in this
study was the number of trials in which this ceiling was equalled or exceeded. It was felt that a more elaborate unjustified
analysis of the reaction time data was in view
of the
relative
crudeness
of the
psychiatric rating.However, the measure does not distinguish between ‘¿slow' and ‘¿omitted'responses.
A measure of premature responseswas also obtained; this represented stimuli
a response
to the warning
signal
rather than to the signal itself.
P@ychophjsiological measures: The psychophysio logical measures taken were H.R. and S.C. during basal state recordings (io-minute period of no
ten-minute
resting
period.
The criterion
of a fluctua.@
graph attached to the ear lobe. The pulse signal produced was converted into a running histogram of heart rate. The data for analysis were selected in the
following way. The highest and lowest heart rate recorded in a io sec. epoch at onset and immediately preceding the end of the ten-minute resting period. were assessed. Consequently for each session: the highest
four scores were derived and lowest heart rates at
both onset and end of the basal period. RESULTS
stimulation).It was found impracticable to assess Reaction time, premature responses and responsivity to stimulation, in addition, for the
following three reasons. During depressive periods, little if any responsivity could be found to fairly
psychiatric ratings
Fig. i indicates the mean number of reaction
intensetones.Lader and Wing (1969)reportsimilar times more than or equal to 450 m.sec. (N) at each point on the psychiatric rating scale. difficulties with retarded depressed patients. Re peated
testing
over
a number
of months
led to an
Fig. 2 indicates the mean number of premature
added confusion: habituation of responsivity. Finally,
responses
there were large practical problems of keeping the
signal, at each point on the psychiatric rating scale.
patient seated with electrodes and earphones on for more than io minutes within a hypomanic phase. All in all, it became necessary to assess only resting data.
(P),
i.e.
responses
As can be seen, it appears
to
the
warning
that the frequency
of slow responses is related to the depressive
The actual measures (S.C. and H.R.) were chosen for their relevance to previous work on depression,
mood swings, whereas the premature vary with the hypomanic episodes.
ease of measurement,
number of observations at each point on the rating scale precludes an analysis of differences
and well-documented
associa
tion with changes (increments and decrements) with
responses The small
MODELS OF MANIA: AN INDIVIDUAL CASE STUDY
82
between mood levels. The correlation between rating and N, over the fifteen drug-free sessions, is —¿036 (n = I 5, NS). This is in the direction of increasing frequency of long reaction times
110
@
90
with
70
increasing
depression.
If the
last
four
sessions, during which the patient was receiving lithium, are included, the correlation rises to —¿o6o(n = ‘¿9, p < o.oi). The correlation between premature responses (P) and mood ratings is significant, whether or
2 A 30 10
not —¿1
0
+1
+2
+3
Psychiatricrating
one
includes
the
final
n = 15, r = +o84 n = 19, r —¿+o8I increasing
mania
four
trials.
With
(p < o.ooi), and with (p < o@ooI). Thus
is significantly
associated
with
the occurrence of premature responses. FIG. I.
It
appears
therefore
that
the
reaction
time
index (N), marks the depressive range, whereas 12
the
10
A
responses
derived
@
sessions
@3
was
—¿08 I (p