/. biosoc. Sci. (1978) 10,401-408
SENSATION SEEKING AND GONADAL HORMONES REID J. DAITZMAN*, MARVIN ZUCKERMANt, PAUL SAMMELWITZJ AND VENKATASESHU GANJAM§ * Department of Psychology, Fairfield University, ^Department of Psychology, University of Delaware, % Department of Agricultural Biochemistry, University of Delaware and ^School of Veterinary Medicine, University of Pennsylvania (Received 30th January 1978) Summary. Two samples of male students (N = 25, and N = 51) and a small sample of female students (N = 7) were administered the Sensation Seeking Scale (SSS), and blood samples were drawn on two occasions to determine plasma levels of androgens and oestrogens. Reliable and significant simple and partial correlations were found between the sex hormones and the SSS subscale, Disinhibition. Partial correlations simultaneously controlled for height, weight, age, and recency of orgasm. Introduction
The Sensation Seeking Scale (SSS II, Zuckerman et al., 1964) was developed to assess individual differences in 'optimal levels' of stimulation or arousal. Since the original SSS II was published in 1964, four new scales, based on factor analyses, were added to the General scale (Zuckerman, 1971): Thrill and Adventure Seeking, Experience Seeking, Disinhibition, and Boredom Susceptibility. This new form (SSS IV) was used in the present study. The SSS has been correlated with behaviour such as volunteering for unusual or risky activities, drinking, smoking, drug usage, and sexual behaviour, and has been found to correlate consistently with the Hypomania Scale of the MMPI (Zuckerman, 1974). The sensation seeker needs varied, novel, and complex sensations and experiences to maintain an optimal level of arousal. He is presumed to be more sensitive to inner sensations and less conforming to external constraints (Zuckerman et al., 1972). In general, the research on the SSS has demonstrated the usefulness of a generalized construct involving individual differences based on optimal levels of stimulation or arousal (Zuckerman, 1974). The relationships between forms II and IV of the SSS and the extraversion (E), neuroticism (N), and psychoticism (P) dimensions, defined by Eysenck have been discussed in previous publications (Zuckerman, 1974, 1978). A number of studies have shown that the SSS has low positive and significant correlations with the E Address for offprints: Dr R. J. Daitzman, 1425 Bedford Street, 1A, Stamford, Ct, USA. 401
402
R. J. Daitzman et al.
scale but no relationship to the N scale. Relationships were also found between the SSS and P scale. A recent study (Eysenck & Zuckerman, 1978), examined the relationships between the SSS form V and the Eysenck & Eysenck (1975) EPQ. The SSS total score correlated positively with both the E and P scales in both English and American samples. The correlations in the English sample were of the 0-2-0*3 magnitude typically found in previous studies. As in previous studies, the N scale proved to be unrelated to the SSS. Among the subscales the Disinhibition scale was the most consistently and highly related to E and P. Other work has shown that the SSS correlates more with the impulsivity factor in extraversion than with the sociability factor (Farley & Farley, 1970). In a recent study done in England (Fulker, Eysenck & Zuckerman, 1977, unpublished) the SSS IV was given to large samples of MZ and DZ twins and the results were analysed using the latest methods of biometrical statistics (Jinks & Fulker, 1970). The results show a strong genetic influence in sensation seeking, relative to results found on other personality variables. Data from previous studies indicate some of the neurophysiological and biochemical mechanisms which might be involved in the genotype. A study was done on habituation of the electrodermal orienting reflex (OR) (Zuckerman, 1972). High scoring subjects on the General SSS have greater ORs than low scoring subjects on initial stimulus presentations, but habituated to the level of the low scorers by the second stimulus presentations. Neary & Zuckerman (1976) extended these findings from visual to auditory stimulation. These results suggested that high sensation seekers are hyperarousable in response to novel stimulation but do not differ from low scorers in response to repeated stimulation. Buchsbaum (1971) devised a method which might be used for studying stimulusresponse characteristics of the CNS more directly through the averaged evoked response (AER). He noted that the relationship between stimulus intensity and AER amplitude was not a simple positive monotonic function in all subjects. In some individuals the amplitude of the AER increases directly with increase of stimulus intensity (Augmenters), while in others the AER shows little increase with intensity and may even diminish, at the higher stimulus intensities (Reducers). He suggested that the sensation seeking trait in normal subjects might be related to augmentingreducing and found non-significant results, but in the expected positive direction. Zuckerman, Murtaugh & Siegel (1974) extended Buchsbaum's study and found that the Disinhibition scale correlated with cortical augmention. Subjects were presented with five intensities of light flashed in randomly presented blocks of trials at each intensity, and AER amplitudes were measured for each intensity of light. Augmenting-reducing was measured for each subject as the slope of the relationship between stimulus intensity and amplitude of response. This slope measure correlated highly and significantly with the Disinhibition subscale of the SSS, but not significantly with other subscales. The authors suggested that reducing reflects the inhibitory process in the reticulo-cortical feedback system. However, a recent study by Lucas (unpublished doctoral dissertation, 1976) using implanted electrodes to stimulate the visual area and record from other areas in cats, established that the reducing effect occurs above the thalamic level and may actually have a cortical origin. The study also showed that cats who were augmenters, by Buchsbaum's
Sensation seeking and gonadal hormones
403
criteria, showed behavioural characteristics compatible with the human sensation seeker, i.e. more behaviourally and emotionally responsive to novel stimuli. A study by Coursey, Buchsbaum & Fracnkcl (1975) found a significant relationship between augmenting in response to auditory stimuli and the General SSS in a group of insomniacs and controls. Another set of data deals with relationships bewcen sensation seeking and monoamine oxidase (MAO), a brain enzyme which inactivates the monoamine norepinephrine. Norepinephrine is believed to be the primary neurotransmitter of the central adrenergic nervous system. More generally, MAO is a major enzyme in the catabolism of brain biogenic amines and plays an important role in the regulation of intra-neuronal levels of monoamines. Central levels of brain MAO are inferred through circulating levels of platelet MAO although the nature of the real relationship is uncertain. There is recent evidence that sex hormones can affect MAO activity and regulate adrenergic arousal (Broverman et al., 1974). In humans there are changing levels of MAO in association with blood oestrogen concentrations (Briggs & Briggs, 1972), the menstrual cycle (Klaiber et al., 1971), and in amenorrhoeic and menopausal women (Klaiber et al., 1971). Broverman et al. (1968) conclude that 'androgens (and estrogens) tend to lower MAO activity . . . and, presumably, thereby increase amine levels in the activating sympathetic nervous system'. Murphy et al. (1978) found significant negative correlations between SS General, Disinhibition, and Boredom Susceptibility scales and platelet MAO in a sample of male college students, but could not replicate the relationships in females. However, a subsequent study by Schooler et al. (1977, unpublished) found significant correlations between the SSS General and Experience Seeking subscales and platelet MAO for samples of male and female college students. All of the SS scales correlated significantly with MAO in the combined group. Replicated findings of low MAO levels in high sensation seekers suggests that they may have high levels of norepinephrine and other neural transmitters in the brain which might account for the greater neural responsiveness to high levels of stimulation. Although the link between MAO levels and gonadal hormones is rather speculative, the finding of low MAO levels in high sensation seekers would lead to the prediction of high levels of gonadal hormones in these persons. The present study provides a test of this correlational hypothesis. Method Subjects This experiment involved two separate male samples of 25 and 51 subjects respectively. The 76 male subjects were unmarried, white, 18-23 years old and in good general health; they received 1 hour 'experimental credit' for their volunteer participation. Seven females were also in the second experiment. They were all unmarried, not on steroid contraceptives, and reported regular menstrual periods. Their mean age was 19 years. Throughout the experiment, all subjects remained fully informed as to the purpose and details of the study, and all subjects co-operated fully in all phases of the experiment.
404
R. J. Daitzman et al.
Procedure Experiment I(N = 25 males). The Sensation Seeking Scale Form IV was administered to an entire Introductory Psychology class as part of a series of research projects. At the next session the experimenter distributed a consent form explaining the nature of the experiment and the requirement for a small blood sample. Of the students who signed the form, 25 were later contacted by telephone, and a convenient date was arranged for them to come to the Student Health Service for a blood sample. All blood samples were drawn between 08.00 and 09.15 hours. Subjects were asked not to eat or drink on the morning of taking the blood sample. In this smaller sample, blood was drawn only once while sitting in a chair. On arrival at the Student Health Service, the student's health chart was checked for any illnesses, etc. which may affect the endocrine system. No such abnormalities were found with any subject. An experienced laboratory technician then withdrew 10 ml of blood (venous puncture) into prepared heparin vials which were immediately centrifuged, supernatant plasma withdrawn, and frozen at 5°F. The frozen plasma samples were coded, and a single blind analysis was performed assaying for androgen using competitive protein binding (Sammelwitz, 1974, unpublished). Experiment II (N = 51 males and 7females). In this experiment blood was drawn twice over a 10-day period to assess the reliability of individual levels of the hormones and provide a more stable value than in Experiment I by averaging the two results. All 51 males in Experiment II returned for their second blood sample. The procedure was the same as in Experiment I except that the subjects in Experiment II completed additional personality questionnaires as part of a larger project. While waiting for his blood sample to be drawn, all subjects completed a physical data sheet, requesting such data as height, weight, age, general health, and recency of orgasm. These factors were used in partial correlation analysis to control for their possible effects on hormone levels. At the time of Experiment I, only the androgen assays were available. By the time of Experiment II both androgen and oestrogen assays were possible so data from this experiment include correlations between the SSS and oestrogens as well as androgens. Androgens were measured by competiiive protein binding (Sammelwitz, 1974, unpublished) and oestrogens by radioimmunoassay (Mikhail et al., 1970). Final hormone levels were expressed in ng/100 ml. The obtained psychological and endocrine data were analysed at the University of Delaware Computing Center, Burroughs 5500. Results Table 1 summarizes the percentage recovery, coefficient of variation and sensitivity of the hormone assays in Experiments I and II. In both experiments the values are within acceptable ranges for these assays. There was no significant difference between average androgen levels on the two sampling occasions in Experiment II, therefore subjects' androgen levels from both samples were averaged for further statistical analyses. The androgen levels derived from blood samples 1 and 2 were also highly reliable (r = 0-77, df = 0-50, P < 0-001).
Sensation seeking and gonadal hormones
405
Table 1. Summary of percentage recovery, intra- and inter-assay coefficient of variation, and sensitivity in hormone assays in Experiments I and II
Experiment I (N = 25 males) Androgen Experiment II* (N = 51 males) Androgen Oestrogen
Recovery
CV
Sensitivity ng/lOOml
86+11 (Ethanol)
10-15
10
90±8 (Ethanol) 98-6 (Ether)
10-15
10
10
0-5
*Antibody, 17B-oestradiol, 17-hemisuccinate BSA at 1:75,0O0 at 50% binding.
There was no significant difference between average oestrogen levels from the two samples and subjects' oestrogen levels were also averaged for further statistical analysis. The oestrogen levels were also reliable (r = 0-72, df = 50, P < 0-001), from one occasion to the next. Personality-hormone relationships Table 2 contains the simple and partial correlation coefficients of the SSS and sex hormone variables. In Experiment I only the Disinhibition subscale was significantly related to androgen. Oestrogens were not assayed in this experiment, and physical data were not available for partial correlation analysis. In Experiment II the Disinhibition subscale was significantly correlated with both androgens and oestrogens. The partial correlations, which simultaneously controlled for height, weight, age, and recency of orgasm, were also significant. The endocrine variables were entered into a step-wise multiple regression equation as independent variables, with the Disinhibition subscale as the dependent variable. The androgen level made a significant contribution to the total Disinhibition variance (14%, F = 5-25, P < 0-05). Disinhibition was the only subscale to have a significant variance accounted for by sex hormones. The other four SS subscales were used as dependent variables and the sex hormones as independent variables, but none of the accounted variance was statistically significant. Female data A small female sample (N = 7) participated in Experiment II in addition to the 51 males. Their blood was drawn to coincide with the luteal and follicular stages of the menstrual cycle, when the oestrogen is lowest and highest, respectively. The percentage recovery, coefficient of variation, and sensitivity of their hormone assays were identical to the Experiment II male assay. Follicular and luteal androgens and oestrogens were within normal limits.
406
R. J. Daitzman et al.
Table 2. Simple and partial correlation coefficients of sex hormones versus sensation seeking scale (SSS) Experiment II N = 7 females
N = 51 males Experiment I
sss General Thrill and Adventure Experience Seeking Disinhibition Boredom Susceptibility
Androgen
Oestrogen
Androgen
Androgen
Oestrogen
Ft
Ft
-Oil
003
-008
-005
003
0-50 0-66 -0-46 -0-25
-004 0-37** 0-36**f
0-25 0-37** O-33*t
0-70 0-21 - 0 1 6 0-35 0-60 0-20 0-77* 0-70*
-001 0-56** 006
0-29* 0-30*t
003
003
0-59 0-35 -0-30
14
0-73 0-30
0-34
0-21
0-74
t Partial correlation coefficient simultaneously controlling for height, weight, age, and recency of orgasm. t F = follicular; L = luteal. *P
SENSATION SEEKING AND GONADAL HORMONES REID J. DAITZMAN*, MARVIN ZUCKERMANt, PAUL SAMMELWITZJ AND VENKATASESHU GANJAM§ * Department of Psychology, Fairfield University, ^Department of Psychology, University of Delaware, % Department of Agricultural Biochemistry, University of Delaware and ^School of Veterinary Medicine, University of Pennsylvania (Received 30th January 1978) Summary. Two samples of male students (N = 25, and N = 51) and a small sample of female students (N = 7) were administered the Sensation Seeking Scale (SSS), and blood samples were drawn on two occasions to determine plasma levels of androgens and oestrogens. Reliable and significant simple and partial correlations were found between the sex hormones and the SSS subscale, Disinhibition. Partial correlations simultaneously controlled for height, weight, age, and recency of orgasm. Introduction
The Sensation Seeking Scale (SSS II, Zuckerman et al., 1964) was developed to assess individual differences in 'optimal levels' of stimulation or arousal. Since the original SSS II was published in 1964, four new scales, based on factor analyses, were added to the General scale (Zuckerman, 1971): Thrill and Adventure Seeking, Experience Seeking, Disinhibition, and Boredom Susceptibility. This new form (SSS IV) was used in the present study. The SSS has been correlated with behaviour such as volunteering for unusual or risky activities, drinking, smoking, drug usage, and sexual behaviour, and has been found to correlate consistently with the Hypomania Scale of the MMPI (Zuckerman, 1974). The sensation seeker needs varied, novel, and complex sensations and experiences to maintain an optimal level of arousal. He is presumed to be more sensitive to inner sensations and less conforming to external constraints (Zuckerman et al., 1972). In general, the research on the SSS has demonstrated the usefulness of a generalized construct involving individual differences based on optimal levels of stimulation or arousal (Zuckerman, 1974). The relationships between forms II and IV of the SSS and the extraversion (E), neuroticism (N), and psychoticism (P) dimensions, defined by Eysenck have been discussed in previous publications (Zuckerman, 1974, 1978). A number of studies have shown that the SSS has low positive and significant correlations with the E Address for offprints: Dr R. J. Daitzman, 1425 Bedford Street, 1A, Stamford, Ct, USA. 401
402
R. J. Daitzman et al.
scale but no relationship to the N scale. Relationships were also found between the SSS and P scale. A recent study (Eysenck & Zuckerman, 1978), examined the relationships between the SSS form V and the Eysenck & Eysenck (1975) EPQ. The SSS total score correlated positively with both the E and P scales in both English and American samples. The correlations in the English sample were of the 0-2-0*3 magnitude typically found in previous studies. As in previous studies, the N scale proved to be unrelated to the SSS. Among the subscales the Disinhibition scale was the most consistently and highly related to E and P. Other work has shown that the SSS correlates more with the impulsivity factor in extraversion than with the sociability factor (Farley & Farley, 1970). In a recent study done in England (Fulker, Eysenck & Zuckerman, 1977, unpublished) the SSS IV was given to large samples of MZ and DZ twins and the results were analysed using the latest methods of biometrical statistics (Jinks & Fulker, 1970). The results show a strong genetic influence in sensation seeking, relative to results found on other personality variables. Data from previous studies indicate some of the neurophysiological and biochemical mechanisms which might be involved in the genotype. A study was done on habituation of the electrodermal orienting reflex (OR) (Zuckerman, 1972). High scoring subjects on the General SSS have greater ORs than low scoring subjects on initial stimulus presentations, but habituated to the level of the low scorers by the second stimulus presentations. Neary & Zuckerman (1976) extended these findings from visual to auditory stimulation. These results suggested that high sensation seekers are hyperarousable in response to novel stimulation but do not differ from low scorers in response to repeated stimulation. Buchsbaum (1971) devised a method which might be used for studying stimulusresponse characteristics of the CNS more directly through the averaged evoked response (AER). He noted that the relationship between stimulus intensity and AER amplitude was not a simple positive monotonic function in all subjects. In some individuals the amplitude of the AER increases directly with increase of stimulus intensity (Augmenters), while in others the AER shows little increase with intensity and may even diminish, at the higher stimulus intensities (Reducers). He suggested that the sensation seeking trait in normal subjects might be related to augmentingreducing and found non-significant results, but in the expected positive direction. Zuckerman, Murtaugh & Siegel (1974) extended Buchsbaum's study and found that the Disinhibition scale correlated with cortical augmention. Subjects were presented with five intensities of light flashed in randomly presented blocks of trials at each intensity, and AER amplitudes were measured for each intensity of light. Augmenting-reducing was measured for each subject as the slope of the relationship between stimulus intensity and amplitude of response. This slope measure correlated highly and significantly with the Disinhibition subscale of the SSS, but not significantly with other subscales. The authors suggested that reducing reflects the inhibitory process in the reticulo-cortical feedback system. However, a recent study by Lucas (unpublished doctoral dissertation, 1976) using implanted electrodes to stimulate the visual area and record from other areas in cats, established that the reducing effect occurs above the thalamic level and may actually have a cortical origin. The study also showed that cats who were augmenters, by Buchsbaum's
Sensation seeking and gonadal hormones
403
criteria, showed behavioural characteristics compatible with the human sensation seeker, i.e. more behaviourally and emotionally responsive to novel stimuli. A study by Coursey, Buchsbaum & Fracnkcl (1975) found a significant relationship between augmenting in response to auditory stimuli and the General SSS in a group of insomniacs and controls. Another set of data deals with relationships bewcen sensation seeking and monoamine oxidase (MAO), a brain enzyme which inactivates the monoamine norepinephrine. Norepinephrine is believed to be the primary neurotransmitter of the central adrenergic nervous system. More generally, MAO is a major enzyme in the catabolism of brain biogenic amines and plays an important role in the regulation of intra-neuronal levels of monoamines. Central levels of brain MAO are inferred through circulating levels of platelet MAO although the nature of the real relationship is uncertain. There is recent evidence that sex hormones can affect MAO activity and regulate adrenergic arousal (Broverman et al., 1974). In humans there are changing levels of MAO in association with blood oestrogen concentrations (Briggs & Briggs, 1972), the menstrual cycle (Klaiber et al., 1971), and in amenorrhoeic and menopausal women (Klaiber et al., 1971). Broverman et al. (1968) conclude that 'androgens (and estrogens) tend to lower MAO activity . . . and, presumably, thereby increase amine levels in the activating sympathetic nervous system'. Murphy et al. (1978) found significant negative correlations between SS General, Disinhibition, and Boredom Susceptibility scales and platelet MAO in a sample of male college students, but could not replicate the relationships in females. However, a subsequent study by Schooler et al. (1977, unpublished) found significant correlations between the SSS General and Experience Seeking subscales and platelet MAO for samples of male and female college students. All of the SS scales correlated significantly with MAO in the combined group. Replicated findings of low MAO levels in high sensation seekers suggests that they may have high levels of norepinephrine and other neural transmitters in the brain which might account for the greater neural responsiveness to high levels of stimulation. Although the link between MAO levels and gonadal hormones is rather speculative, the finding of low MAO levels in high sensation seekers would lead to the prediction of high levels of gonadal hormones in these persons. The present study provides a test of this correlational hypothesis. Method Subjects This experiment involved two separate male samples of 25 and 51 subjects respectively. The 76 male subjects were unmarried, white, 18-23 years old and in good general health; they received 1 hour 'experimental credit' for their volunteer participation. Seven females were also in the second experiment. They were all unmarried, not on steroid contraceptives, and reported regular menstrual periods. Their mean age was 19 years. Throughout the experiment, all subjects remained fully informed as to the purpose and details of the study, and all subjects co-operated fully in all phases of the experiment.
404
R. J. Daitzman et al.
Procedure Experiment I(N = 25 males). The Sensation Seeking Scale Form IV was administered to an entire Introductory Psychology class as part of a series of research projects. At the next session the experimenter distributed a consent form explaining the nature of the experiment and the requirement for a small blood sample. Of the students who signed the form, 25 were later contacted by telephone, and a convenient date was arranged for them to come to the Student Health Service for a blood sample. All blood samples were drawn between 08.00 and 09.15 hours. Subjects were asked not to eat or drink on the morning of taking the blood sample. In this smaller sample, blood was drawn only once while sitting in a chair. On arrival at the Student Health Service, the student's health chart was checked for any illnesses, etc. which may affect the endocrine system. No such abnormalities were found with any subject. An experienced laboratory technician then withdrew 10 ml of blood (venous puncture) into prepared heparin vials which were immediately centrifuged, supernatant plasma withdrawn, and frozen at 5°F. The frozen plasma samples were coded, and a single blind analysis was performed assaying for androgen using competitive protein binding (Sammelwitz, 1974, unpublished). Experiment II (N = 51 males and 7females). In this experiment blood was drawn twice over a 10-day period to assess the reliability of individual levels of the hormones and provide a more stable value than in Experiment I by averaging the two results. All 51 males in Experiment II returned for their second blood sample. The procedure was the same as in Experiment I except that the subjects in Experiment II completed additional personality questionnaires as part of a larger project. While waiting for his blood sample to be drawn, all subjects completed a physical data sheet, requesting such data as height, weight, age, general health, and recency of orgasm. These factors were used in partial correlation analysis to control for their possible effects on hormone levels. At the time of Experiment I, only the androgen assays were available. By the time of Experiment II both androgen and oestrogen assays were possible so data from this experiment include correlations between the SSS and oestrogens as well as androgens. Androgens were measured by competiiive protein binding (Sammelwitz, 1974, unpublished) and oestrogens by radioimmunoassay (Mikhail et al., 1970). Final hormone levels were expressed in ng/100 ml. The obtained psychological and endocrine data were analysed at the University of Delaware Computing Center, Burroughs 5500. Results Table 1 summarizes the percentage recovery, coefficient of variation and sensitivity of the hormone assays in Experiments I and II. In both experiments the values are within acceptable ranges for these assays. There was no significant difference between average androgen levels on the two sampling occasions in Experiment II, therefore subjects' androgen levels from both samples were averaged for further statistical analyses. The androgen levels derived from blood samples 1 and 2 were also highly reliable (r = 0-77, df = 0-50, P < 0-001).
Sensation seeking and gonadal hormones
405
Table 1. Summary of percentage recovery, intra- and inter-assay coefficient of variation, and sensitivity in hormone assays in Experiments I and II
Experiment I (N = 25 males) Androgen Experiment II* (N = 51 males) Androgen Oestrogen
Recovery
CV
Sensitivity ng/lOOml
86+11 (Ethanol)
10-15
10
90±8 (Ethanol) 98-6 (Ether)
10-15
10
10
0-5
*Antibody, 17B-oestradiol, 17-hemisuccinate BSA at 1:75,0O0 at 50% binding.
There was no significant difference between average oestrogen levels from the two samples and subjects' oestrogen levels were also averaged for further statistical analysis. The oestrogen levels were also reliable (r = 0-72, df = 50, P < 0-001), from one occasion to the next. Personality-hormone relationships Table 2 contains the simple and partial correlation coefficients of the SSS and sex hormone variables. In Experiment I only the Disinhibition subscale was significantly related to androgen. Oestrogens were not assayed in this experiment, and physical data were not available for partial correlation analysis. In Experiment II the Disinhibition subscale was significantly correlated with both androgens and oestrogens. The partial correlations, which simultaneously controlled for height, weight, age, and recency of orgasm, were also significant. The endocrine variables were entered into a step-wise multiple regression equation as independent variables, with the Disinhibition subscale as the dependent variable. The androgen level made a significant contribution to the total Disinhibition variance (14%, F = 5-25, P < 0-05). Disinhibition was the only subscale to have a significant variance accounted for by sex hormones. The other four SS subscales were used as dependent variables and the sex hormones as independent variables, but none of the accounted variance was statistically significant. Female data A small female sample (N = 7) participated in Experiment II in addition to the 51 males. Their blood was drawn to coincide with the luteal and follicular stages of the menstrual cycle, when the oestrogen is lowest and highest, respectively. The percentage recovery, coefficient of variation, and sensitivity of their hormone assays were identical to the Experiment II male assay. Follicular and luteal androgens and oestrogens were within normal limits.
406
R. J. Daitzman et al.
Table 2. Simple and partial correlation coefficients of sex hormones versus sensation seeking scale (SSS) Experiment II N = 7 females
N = 51 males Experiment I
sss General Thrill and Adventure Experience Seeking Disinhibition Boredom Susceptibility
Androgen
Oestrogen
Androgen
Androgen
Oestrogen
Ft
Ft
-Oil
003
-008
-005
003
0-50 0-66 -0-46 -0-25
-004 0-37** 0-36**f
0-25 0-37** O-33*t
0-70 0-21 - 0 1 6 0-35 0-60 0-20 0-77* 0-70*
-001 0-56** 006
0-29* 0-30*t
003
003
0-59 0-35 -0-30
14
0-73 0-30
0-34
0-21
0-74
t Partial correlation coefficient simultaneously controlling for height, weight, age, and recency of orgasm. t F = follicular; L = luteal. *P
