Section 9:  Purposes of Sex

Measuring Subgoals of the Sexual Behavioral System: What is Sex Good For?

Evolutionary Perspective

Major function of the sexual behavioral system is to pass one’s genes to the next generation.
To increase the children’s chance of survival and eventual reproduction, sexual partners must stay together long enough to maintain the pregnancy and care for offspring.
Focus on species-typical adaptation, neglecting the importance of individual differences based on particular sexual-system subgoals and associated psychological mechanisms.

Measuring Subgoals of the Sexual Behavioral System
Individual differences can emerge from a combination of heritable and non heritable sources.
These differences in the subgoals of the sexual behavioral system might be translated into corresponding individual differences in behavioral intentions and actual sexual behavior.

Primary goal of Investigation
To devise a measurement of these individual differences.
Measuring Subgoals of the Sexual Behavioral System
Previous studies on individual differences have examined one of four domains:
    Differences in sexual attitudes: such as the tendency to respond to sexual stimuli along a negative to positive dimension of affect and evaluation.
    Differences in physiological aspect of sexuality: such as individual differences in sexual arousal .
    Differences in sexual behavior: such as individual differences in the willingness to engage in sexual intercourse without relational commitment.
    Differences in cognitive representations of sexuality: such as individual differences in sexual self-concept.

To provide a research tool suitable for both men and women, that assesses a person’s beliefs about the various personal and interpersonal rewards and costs of sexual activity and related behaviors from an evolutionary perspective.
To assess four major subgoals of the sexual behavior system that may play a role in both men’s and women’s reproductive success in the context of long-term adult romantic relationships.
Major subgoals of the sexual behavior system
    1st subgoal: To bring partners together and establish a relationship by means of sexual activity
        Successful human mating often depends, and depended during human evolution, on relationship formation
        Without a relationship between the parents their offspring might be much less likely to survive to reproductive age.
        Thus, one goal of sexual activity can be to create a relationship with someone that extends beyond a single sexual episode.

    2nd subgoal: To keep partners attached to each other for an extended period of time.
        Several unusual characteristics of human reproductive physiological, anatomy, and behavior imply that the sexual system foster not only the formation of an emotional bond between sexual partners but also its maintenance.
        Example : Female Ovulation is Concealed
        “Keep daddy-at-home” hypothesis
        Concealed ovulation increases the probability of offspring survival by inducing the male partner to stay “at home” for two reasons:
        To have frequent sex with partner and guard against her impregnation by other males

    3rd Subgoal: The possible personal and interpersonal rewards of sexual activity that contributes to one’s reproductive success through the formation and/or maintenance of an emotional bond between sexual partners.
        Nevertheless, along with the potential for gratification and delight, human sexuality may sometimes be a source of negative feelings.
        Aversive sexuality can be a dysfunctional consequence of negative sexual experiences associating sexual thoughts with negative feelings such as pain, fear and guilt.
        The existence of pervasive cultural and religious norms, mores and etc that surround sexuality.

    4th subgoal: To restrict the expressions of sexuality when sexual activity is viewed as aversive and incompatible with other important personal and interpersonal goals.
        Perceiving sexuality as aversive may be linked to individual differences in mating strategies: Uncommitted sexual relations and Monogamous sexual strategy.
        Aversive sexuality might have evolved to maximize reproduction benefits of the monogamous sexual strategy through restraining sexual desire and its behavioral manifestation
        Signifying a faithful, trustworthy and valuable long-term mate in the eyes of potential partners.

Pilot Study
The investigators developed a self-report questionnaire of the Sexual Behavioral System Subgoals (SBSS)

    Sample included 398 Israeli undergraduates; 219 women and 179 men ranging from 18 to 50 years of age.
    62.5% Single, 37.5% Married. All participants had experienced heterosexual intercourse either in a current or past relationship.
    Measurement used: 26 Questionnaire items derived from the Experience of Heterosexual Intercourse Scale (EHIS), Investigators and 8 graduate psychology students.

    It was determined that the internal structure and the loadings pattern of the SBSS were very similar in the men and women sample.


Study 1 evaluated the structure of SBSS and provided initial evidence for its convergent and incremental validity. Studies 2 and 3 provided additional evidence for the reliability and validity of the scale. In study 4, the investigators presented cross-national evidence for the generalizability of the measure’s underlying factor structure.

Study 1: Methods

Sample included 128 Israeli undergraduate; 66 women and 62 men ranging from 19 to 50

Measurements included: revised 18 item version of the SBSS, THE Israeli Sexual Behavior Inventory (ISBI), The Expanded Sexual Arousablilty Index (SAI-E), Hebrew version of the Women’s Sexual Self-Schema Scale, Sexual Opinion Survey (SOS), Sociosexual Orientation Inventory (SOI) and Demographic Questions

Study 1: Results and Discussion
Men and women showed a similar pattern of association between the SBSS factors and sexuality measures
With exceptions of association between pleasure and motivation and the willingness to engage in uncommitted sexual anxiety, which was significant for men.
Significant for women was the association between the pleasure and motivation and orgasmic responsivity.
These sex-specific findings imply that men’s sex-related affect and cognitions may be a manifestation of short-term mating strategy preference combined with self-enhancing motivation.
Women, on the other hand, may be more complex and less affected by relationship-irrelevant motives.
Overall, Men in comparison to Women, reported a greater usage of sex as a means of initiating romantic relationships.
Also, men were more likely to perceive sex as a strong motivator and as a source of leisure and joy than women .
Study 1 findings are in line with the theoretical approached to human sexuality and empirical evidence suggesting:
Women adopt a more emotional-interpersonal aspects during sexual intercourse.
Men develop a more recreational orientation toward their sexuality and place a greater emphasis on expressing their sexual needs and on taking the initiative and dominant role of courting.

Study 2: Methods

Sample included 130 Israeli, 80 women and 50 men ranging from 18 to 64 years of age.

Measurements included: 18-item version of the SBSS; Hebrew version of: Rosenberg’s (1979) Self-esteem Scale, Marlowe-Crowne Social Desirability Scale, Neuroticism Subscale of the Eysenck Personality Inventory, Extraversion Subscale and Openness to Experience from the NEO personality Inventory, Relationship Assessment Scale, Experience in Close Relationship Scale and a series of demographic questions.

Results and Discussions
The pattern of association between personality domains and negative and positive sex-related affect is in line with previous findings:
The role of personality in women’s sexuality may operate differently depending upon the developmental stage is a woman’s sexual life.
The relationship of negative reactions and sexual pleasure and motivation with the personality measures are consistent with prior findings
Showing that neuroticism is associated with low sexual satisfaction as well as high degree of worry and guilt feeling about sex and seeing behavior as disgusting.
Extroversion is associated with intensified sexual behavior
The tendency to experience negative reactions in sexuality was positively correlated with attachment avoidance and attachment anxiety
It was also negatively associated with relationship satisfaction in women.

Study 3: Methods

Sample included 58 Israeli Undergraduates, 18 men and 40 women, ranging from19 to 40 years if age.

Measurements included: 18-item version of the SBSS, the Israeli Sexual Behavior Inventory, and Hebrew Versions: Neuroticism, Relationship Satisfaction, and Adult attachments

Results and Discussions
The contribution of the sexual behavioral system accounted for significant increments in explained variance beyond neuroticism, attachment and relationship satisfaction scores in predicting orgasmic responsively, sexual arousal and sexual satisfaction.
Relationship Initiation and negative reaction were associated with orgasmic responsivity.
Negative reaction, sexual pleasure and motivation were associated with sexual arousal
Negative reaction was associated with sexual satisfaction.

Study 4: Methods

Sample included 476 undergraduates, 157 men and 319 women ranging from 17 to 35 years of age. The sample was ethnically diverse.
Measurement included: An English version of the SBSS as part of an internet survey

Results and Discussion
The correlation between the SBSS subscales were mostly small to moderate indicating that nearly all of the SBSS scores were quite independent of each other
The correlation between Maintaining the bond, sexual pleasure and motivation were rather high.
It was also noted that Study 4 had a younger sample than the Israeli sample and the age difference may account for the different pattern of correlation revealed in the study.

General Discussion
The four subgoals that were proposed at the beginning of the study were supported.

People with unrestricted sexuality, who are more likely to engage in uncommitted sexual relations, rated the desire for possible sex as more important reason for initiating opposite-sex friendships

Although sexual desire and pleasure enhance emotional bonding between sexual partners, the investigators found that sexual partners contribution to relationship satisfaction was rather marginal in comparison to perceiving sexual activity as aversive.

Discussion Questions:

What are the implications of these results in terms of a sexually healthy relationship?

Re-examine the prior discussion question regarding healthy sexuality.  Does your perspective on this question change as a result of the findings in this study?

How might these results be incorporated into a Christian World View?  Explain your answer.