ELSEVIER Journal of Affective Disorders 34 (1995) 219-225

JOURNAL OF

AFFECTIVE DISORDERS

Sensation-seeking and emotional disturbances in depression: relationships and evolution

Solange Carton * , Pauline Morand, Catherine Bungenera, Roland Jouvent

H6pital de la Salpk%?re, Service Psychiatric et CNRS-URA 1957, Pavilion Cl&ambault, 47 bouleuard de I’HGpital, 75651 Paris Ctfdex 13, France

Received 14 July 1994; revised 6 February 1995; accepted 6 February 1995

Abstract

The French abbreviated form of the sensation-seeking scale was given to 183 hospitalized depressed subjects meeting the DSM-III-R criteria for major depression. Depressed subjects, men and women, scored significantly lower than controls from the general population, paired as to age and sex, on all of the subscales. There was no relationship to the intensity of depression and anxiety. Relationships between emotional disturbances and sensation-seeking were differentiated according to the specificity of each subscale and to age and sex. There was no significant difference between baseline and after-treatment sensation-seeking scores and subjects at discharge still scored significantly lower than controls. Hypotheses on evolution at a later date after the hospitalization are made. The finding of positive relationships for some subjects between sensation-seeking and anhedonia is interpreted in regard to a compensatory process.

Keywords: Sensation-seeking; Depression; Emotional disturbance; Anhedonia; Personality trait

1. Introduction

Sensation-seeking trait was first directly based on an optimal level of stimulation and arousal theory (Zuckerman, 1969; Zuckerman et al., 1964). On the basis of physiological and biochem- ical findings, Zuckerman proposed a biological model of sensation-seeking, postulating that the trait depends on an optimal level of cate- cholamine system activity (Zuckerman, 1984). Sensation-seeking was defined as the ‘need for

* Corresponding author.

varied, novel and complex sensations and experi- ences and willingness to take physical and social risks for the sake of such experiences’ (Zucker- man, 1969, p. 10). The tendency of the high- sensation seeker to be insensitive to weak stimu- lation and to respond to high intensities of stimu- lation led Zuckerman to point out the relevance of the Pavlovian construct of strength of the nervous system (Zuckerman, 1990). Some authors previously postulated that low levels of arousal or arousability would lead psychopathic personali- ties to seek intense and varied stimulations (Quay, 1965; Farley, 1973). This compensatory theory of arousal, first formulated by Eysenck (19671, sug-

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220 S. Carton et al. /Journal of Affectille Disorders 34 (1995) 219-225

gested that tonically underaroused persons seek stimuli to bring arousal up to an optimal level. With the new biological development of the sen- sation-seeking theory, Zuckerman underlined the role of dopamine in primary reward systems. There is some evidence that deficit in dopaminer- gic activity is related to anhedonia, loss of emo- tional reactivity and social withdrawal. One could hypothesize that high-sensation seekers have lower levels of tonic activity in the dopaminergic systems and, therefore, use drugs to seek intense and novel stimulation and increase activity in this system (Zuckerman, 1991, p. 422). Zuckerman first emphasized the link between sensation-seek- ing, drug use and psychopathy (Zuckerman, 1978a). Sensation-seeking was found to be high in drug abusers defined in clinical groups Kilpatrick et al., 1976) and in smokers (Carton et al., 1993; Carton et al., 1994; Zuckerman et al., 1990). Whereas Zuckerman stated that ‘hypomanics are caricatures of impulsive sensation seekers’ (1991, p. 4081, he postulated that sensation-seeking is decreased in depression, since positive emotions are decreased, activity is minimal and social be- havior is often hostile or withdrawn (Zuckerman, 1984; Zuckerman et al., 1980; Zuckerman and Neeb, 1979). High levels of sensation-seeking have been related to the mania scale of the MMPI (Blackburn, 1969; Thorne, 1971) and Zuckerman found that manic-depressives scored higher on sensation-seeking than matched controls (Zucker- man and Neeb, 1979); but formerly unipolar de- pressives did not score lower. Zuckerman never assessed sensation-seeking during a depressive episode. Some studies showed that hospitalized schizophrenics had low levels of stimulation-seek- ing (Brownfield, 19661, related to the intensity of psychomotor retardation (Kish, 1970). Otherwise, it was found that low levels of sensation-seeking were associated with physical anhedonia (Mac Cann et al., 1990).

The relationship between personality and mood disorders is extremely complex. The de- pressive state may alter scores on trait measure- ment (Hirschfeld et al., 1983; Joffe and Regan, 19881 and certain personality dimensions may be predisposing criteria to depression (Akiskal et al., 1983; Boyce et al., 1991). Our first work on sensa-

tion-seeking and depression has shown that de- pressed hospitalized subjects scored much lower on sensation-seeking than controls (Carton et al., 1992). The goal of this study was to replicate and to extend our findings on levels of sensation-seek- ing in depression. First, it was to confirm or negate the findings that levels of sensation-seek- ing do not increase after the period of hospital- ization and treatment, i.e., subjects at discharge are still lower on sensation-seeking whereas normo-thymic. A much larger sample of de- pressed subjects allowed us to focus on this point. A second purpose of this work was to examine the relationships between sensation-seeking and anhedonia. Since the sensation seeker seems to be a hedonist, the anhedonic depressed subject should not be a high-sensation seeker and should not seek pleasure through hedonic stimulations. Nevertheless, we observed that one subgroup of anhedonic depressed subjects were high in sensa- tion-seeking, especially on the disinhibition sub- tale. We hypothesized that, whereas sensation- seeking should be globally decreased in de- pressed subjects, there might exist a group of anhedonic subjects who are high-sensation seek- ers. These subjects might seek stimulations to experience pleasure and emotional reactions that they do no longer experience with common and mundane stimulations.

2. Methods

2.1. Subjects

The sample was formed of 183 depressed pa- tients, meeting the DSM-III-R criteria for major depression, hospitalized in Hopital de la Salpetritre (Paris, France) for a 3-week minimum length: 109 women (mean age = 37.6 + 11.6 years) and 74 men (mean age = 38.0 k 10.9 years), scat- tered in a large socio-professional status spec- trum. 85 patients were re-assessed just before discharge. A sample of 183 controls from the general population was paired as to age and sex to the depressed patients (109 women, mean age = 36.6 f 10.6 years; 74 men, mean age = 38.3 f 10.9 years).

S. Carton et al. /Journal of Affective Disorders 34 (1995) 219-225 221

2.2. Procedure Table 2

Each subject was assessed upon admission, before administration of antidepressant treat- ment and in some instances after a placebo- washout period. An extensive psychiatric inter- view was conducted in the morning by an experi- enced clinician to evaluate intensity and form of symptomatology, after which patients were asked to complete the sensation-seeking scale. Subjects were assessed just before discharge, when they were judged as normo-thymic by the clinicians, after at least a 3-week antidepressant treatment; for the majority, assessment was made on day 21. The procedure was identical with that on day 0.

Mean and SD values on sensation-seeking subscales: compar-

isons between after-treatment and control scores. Scores of

subjects after treatment are still significantly lower than con-

trols scores on all of sensation-seeking subscales

Dis

TAS

ES

BS

The following instruments were used: (1) Filled by the clinician: (a) Hamilton depres-

indifference (blunting in the extreme). For some patients, this scale was not used (baseline, n = 181; after treatment, n = 76).

sive rating scale (HDRS) (17-item version; Hamil- ton, 1967); (b) Covi anxiety brief scale (Lipman, 1982); and (cl Jouvent depressive mood scale (Jouvent et al., 1988; Lyon-Caen et al., 1986). This instrument is composed of 20 items filled by the clinician using a 5-point rating scale. It has been demonstrated to have good reliability of its 20 items and a coherent factorial structure with five clearcut and clinically cogent components. These components include anhedonia, sadness, (observed) irritability, (felt> hypersensitivity and hypo/hyper-expressiveness. The anhedonia com- ponent contains the items related to the incapac- ity to experience pleasure, lack of anticipatory pleasure, sensorial anhedonia as well as affective

(2) All patients were asked to complete an abbreviated 40-item version of the sensation- seeking scale (form IV; Zuckerman, 1971), which had been previously translated into French and validated (Carton et al., 1990). The abbreviated version was constructed on the basis of a princi- pal-component analysis (Carton et al., 1992) and closely resembles the sensation-seeking scale (form V; Zuckerman et al., 1978). It includes four subscales: i.e., disinhibition (Dis), thrill- and ad- venture-seeking (TAS), experience-seeking (ES) and boredom susceptibility CBS).

2.3. Statistical analysis

Table I Comparisons of mean (M) and SD values on sensation-seek-

ing subscales: depressed and controls ss. Depressed subjects

score lower than controls on all seeking subscales

Depressed (n = 183) Controls (n = 183)

Men (n = 74) Women (n = 109)

Depressed Controls r test Depressed Controls t test

Dis M 3.8 5.2 0.0004 3.3 4.0 0.05

SD 2.4 2.4 2.5 2.5

TAS M 5.4 6.8 0.003 3.8 5.4 0.0001

SD 3.0 2.4 3.0 2.8

ES M 4.8 6.7 0.0001 4.9 6.4 0.0001

SD 2.6 2.0 2.5 2.2

BS M 2.7 3.8 0.001 2.9 3.7 0.009

SD 2.1 2.0 2.1 2.1

Men and women and patients and controls were compared on each subscale of sensation- seeking using unpaired t test. Patients’ baseline results and after-treatment results were com- pared using paired t test. Pearson’s correlation coefficients were calculated between the sensa- tion-seeking subscales scores and the psychiatric scales scores.

3. Results

3.1. Sensation-seeking results

Baseline results As in control studies, men scored higher than

women on TAS (t test, P < 0.001). By contrast,

After treatment

Mean SD

3.3 2.3

4.4 3.0

5.4 2.5

2.9 2.1

Controls

Mean SD

4.5 2.5

6.0 2.7

6.5 2.1

3.7 2.0

I test/p

0.0005

0.0001

0.0002

0.0025

222 S. Carton et al. /Journal of Affective Disorders 34 (1995) 219-225

they did not score higher on Dis. All sensation- seeking subscales’ scores were significantly nega- tively correlated with age (n = 183, Dis: r = -0.22, P < 0.01; TAS: r = -0.41, P < 0.01; ES: r = -0.24, P~0.01; BS: r = -0.28, P< 0.01). Depressed subjects scored lower than controls on all sensation-seeking subscales (Table 1).

9.

a.

7.

6.

5.

4.

3.

2.

1.

O-

T

,

I i.i Dis

After-treatment results Patients at discharge still scored significantly

lower than controls (Table 2). There was no sig- nificant difference between baseline and after- treatment sensation-seeking scores (Fig. 1). Dif- ferences between baseline and after- treatment scores were computed (A). Distributions of the differences on each sensation-seeking subscale are shown in Fig. 2. Some scores have increased, others have decreased and the differences are

TAS ES SS

Fig. 1. Sensation-seeking subscales scores (mean k SD): base-

line, after treatment and controls. White bars, depressed-sub-

ject baseline scores (n = 85); grey bars, depressed-subject af-

ter-treatment scores (n = 85); black bars, control scores (n =

183). There is no significant difference between baseline and

after-treatment scores and subjects at discharge still score

significantly lower than controls on all sensation-seeking

scales.

_L

I 10 1 l-l

:J_udl 0 I 2 3 4 5 -6 -5 -4 -3 -2 -1

40-

35.

30.

25.

20

15

10

5

0 L&i- -6 -5 -4 -3 -2 -1

A DIS 25

20

I5

IO

5

0 Ld

1

-6 -4 -2 0 2 4 6 8 -8 -6 -4 -i 0

A ES A 65

Fig. 2. Distributions of evolutions between baseline and after- treatment scores on sensation-seeking scales. A, after-treatment

score-baseline score (n = 85).

S. Carton et al. /Journal of Affective Disorders 34 (1995) 219-225 223

most often very weak. Most patients obtain scores of 0, indicating no difference between first and second evaluations.

3.2. Relationship to pathology

Mean HDRS total score was 21.4 k 6.3 and mean Covi’s scale total score was 6.1 + 2.9. There was no significant correlation between the inten- sity of depression, anxiety (HDRS and Covi) and the sensation-seeking scores. The computed cor- relations between the depressive mood factor scores and the sensation-seeking scores in the whole sample of patients show no significant re- sults. In women only, Dis was significantly nega- tively correlated with anhedonia (n = 109, r = -0.21, P < 0.05). Conversely, the more they were emotionally hyperexpressive (labile, incontinent, with an explosive mood), the higher they scored on the ES and BS scales (n = 109, r = 0.27, P < 0.01; r = 0.22, P < 0.05). In men only (n = 72), no significant correlations, positive or negative, emerged between any sensation-seeking scale scores and mood factor scores; we did not re- trieve the positive relationship we had found be- tween emotional deficit and Dis. Nevertheless, in regard to age, there was a trend towards a signifi- cant positive correlation between Dis and anhe- donia in men of < 30 years (n = 20, r = 0.34, P < 0.10) and there was a significant positive cor-

Table 3 Mean and SD values on depressive mood scale factors: com- parisons between baseline and after-treatment scores (paired r test, n = 76). Scores of subjects after treatment are signifi- cantly lower than baseline scores on depressive mood scale factors

Baseline After treatment t test

Mean SD Mean SD lp

Anhedonia 6.6 3.8 2.6 3.4 0.0001 Hypersensitivity 7.1 4.6 3.7 3.3 0.0001 Expressiveness a 0.06 5.3 -0.17 3.3 NS Sadness 4.8 1.7 1.8 1.4 0.0001

a Expressiveness factor which contrasts hyper-expressiveness to hypo-expressiveness items is a dimension which varies from negative to positive valence. Results on this factor illustrate variety of emotional expressiveness in depressed patients.

relation between BS and anhedonia (n = 20, r = 0.5, P < 0.05). No significant correlation was ob- served between emotional expressivity and sensa- tion-seeking subscales.

After treatment and before discharge, all of the patients were judged as normo-thymic by the clinicians and scores on HDRS, Covi and depres- sive mood scales were significantly decreased (P < 0.0001) (Table 3). Differences between base- line and after treatment were computed on the HDRS, Covi’s scale and depressive mood scale. Correlations between the differences on sensa- tion-seeking subscales and psychopathological scales were computed to evaluate covariance in the evolutions. As the sadness decreased (sadness factor of the depressive mood scale), the scores on TAS increased (n = 76, r = -0.24, P < 0.05). No other correlation was observed.

4. Discussion

These results confirm that sensation-seeking is weak during a major depressive episode. Patients of both sexes scored lower than controls on all of the sensation-seeking subscales. Before dis- charge, patients still showed significantly lower scores than control subjects. Most patients did not show increase or decrease in sensation-seek- ing scores; when a difference was observed, it was most of the time a one point difference. Further- more, the proportion of scores that increased is equal to the proportion of scores that decreased and no mean difference emerges. The finding of low levels of sensation-seeking after improvement of depression raises questions about the evalua- tion of a personality trait during a pathological episode. Experience of depression may change personality features. One study has shown that levels of novelty-seeking (Cloninger, 1987) were not affected by depressed state (Joffe et al., 1993) but scores on the harm avoidance dimension were altered. This study is not an estimate of the premorbid situation and it does not indicate that these subjects usually have low levels of sensa- tion-seeking. We may have assessed a trait or some changes in behavior and cognition modified by the depressive state. We observe that levels of

224 S. Carton et al. /Journal of Affectirle Disorders 34 (1995) 219-225

sensation-seeking are low during a depressive episode but it is difficult to state that they are equal or decreased in comparison to a premorbid level. It is possible that scores on sensation-seek- ing change at a later date after hospitalization and longitudinal follow-up of subjects has begun to test this hypothesis.

The relationships between anhedonia and sen- sation-seeking tend to be differentiated according to age and sex. In women, sensation-seeking is associated to emotional hyperexpressivity; and the more they are anhedonic, the lower they score on the Dis subscale. This finding is in accord with the results of literature indicating that sensation- seeking is more often associated to impulsivity, extraversion and exhibitionism (Zuckerman et al., 1972; Zuckerman, 1978b), rather than to a lack of emotional reactivity. On the contrary, the more the young men are anhedonic, the higher they score on the BS subscale; this negative relation- ship only reaches significance for Dis. These re- sults show that among men who are emotionally deficient and indifferent, some obtain high scores of sensation-seeking. This confirms our previous results. The emergence of correlations with BS and Dis subscales may show that these two fac- tors tend to be the most involved in a compen- satory process. It is supported by previous obser- vations of a negative correlation between reactiv- ity scale and sensation-seeking scale (Kahn, 1985) and between arousability and sensation-seeking based on the Reducer Augmenter scale (Davis et al., 1984) or the Strelau temperament inventory (Strelau, 1983). Also, physiological studies show that, for some individuals, conditions of subnor- mal activation are distressing (Stern et al., 1981). In clinical depression, blunted affect does not seem to correspond to a real total lack of emo- tions and the inability to ‘feel’ may be for some patients, paradoxically, experienced as painful. Relationships between BS, Dis and anhedonia in a subgroup of patients may correspond to a ‘de- fense mechanism’ to counterbalance blunted af- fect, to compensate for the inability to experience activation and emotions with weak levels of stim- ulation. Follow-up of subjects is needed to exam- ine how sensation-seeking evolves in conjunction with different forms of emotional disturbances

and may clarify the long-term relationships be- tween sensation-seeking and anhedonia.

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