Hurlbert Index of Sexual Fantasy

Abstract

The Hurlbert Index of Sexual Fantasy (HISF) is a specialized 25-item psychometric assessment developed by clinical sexologist David F. Hurlbert to evaluate the qualitative, cognitive, and affective dimensions of sexual fantasy within clinical and empirical contexts. Introduced in peer-reviewed sexological literature by Hurlbert and Apt (1993), the instrument assesses individual comfort with erotic cognition, the capacity to generate and deploy sexual daydreams for physiological arousal, willingness to communicate erotic imagery to an intimate partner, and the presence of cognitive interference or sexual guilt. Operating on a five-point Likert scale (ranging from All Of The Time to Never), the instrument produces a continuous composite score from 0 to 100, with eleven items reverse-scored to capture both permissive, functional fantasy engagement and maladaptive, guilt-laden cognitive avoidance. Psychometric evaluations across clinical, community, and sexual minority samples demonstrate robust internal consistency (Cronbach’s α typically ranging from .88 to .93) and stable test-retest reliability across four-week intervals (r = .84 to .89). Exploratory and confirmatory factor analyses support a multidimensional yet strongly coherent construct reflecting erotic daydreaming and arousal capacity, dyadic fantasy sharing, and cognitive-affective inhibition. The HISF serves as a critical diagnostic and therapeutic marker in sex therapy, aiding clinicians in delineating between organic sexual dysfunctions and cognitive-affective barriers such as spectatoring, erotophobia, and internalized sexual shame.

Keywords

Hurlbert Index of Sexual Fantasy, HISF, sexual fantasy, erotic cognition, sexual guilt, psychometrics, sex therapy, sexual arousal, cognitive distraction, dyadic sexual communication, female sexual dysfunction, sexual desire

Authors

The Hurlbert Index of Sexual Fantasy was constructed and validated by:

• David F. Hurlbert, Ph.D.: A distinguished clinical sexologist, researcher, and psychotherapist whose scholarly career included affiliations with the United States Department of Health and Human Services (Administration for Children and Families) and military healthcare settings. Dr. Hurlbert developed several foundational instruments in clinical sexology, including the Hurlbert Index of Sexual Assertiveness (HISA) and the Hurlbert Index of Sexual Desire (HISD).
• Carol Apt, Ph.D.: Professor of Sociology and human sexuality researcher at South Carolina State University, Orangeburg, South Carolina. Dr. Apt collaborated extensively with Hurlbert on pioneering comparative investigations into sexual functioning, relational intimacy, and sexual satisfaction across heterosexual, homosexual, and clinical cohorts.

Author Contact Information: Historical correspondence regarding the scale was addressed to David F. Hurlbert, 140 Farnworth Lane, Roswell, Georgia 30075; e-mail: [email protected].

Purpose

The primary purpose of the Hurlbert Index of Sexual Fantasy is to provide a standardized, psychometrically sound instrument capable of assessing how individuals experience, appraise, and utilize erotic thoughts and mental imagery. Historically, human sexuality research focused primarily on the frequency and thematic content of sexual fantasies—documenting how often individuals imagined specific behaviors, partners, or unconventional acts. However, clinical sexologists noted that raw fantasy frequency provides insufficient diagnostic clarity; two individuals reporting daily erotic fantasies may have vastly different psychological profiles if one experiences those thoughts as enriching and arousing, while the other experiences them as intrusive, distressing, or shameful.

The HISF addresses this clinical need by quantifying the functional, affective, and relational integration of sexual fantasy. Specifically, the instrument seeks to determine:

• The respondent’s subjective comfort and ideological endorsement of sexual fantasies as healthy and natural components of adult eroticism.
• The functional utility of mental imagery during solitary sexual behaviors (e.g., masturbation) and partnered sexual encounters.
• The degree to which guilt, shame, and negative memories of past sexual experiences intrude upon erotic cognition, leading to cognitive interference.
• The level of transparency, safety, and comfort the respondent experiences when disclosing personal sexual thoughts to an intimate partner or hearing the partner’s fantasies.

In clinical practice, the HISF is employed during comprehensive sexological assessments for Hypoactive Sexual Desire Disorder (HSDD), Female Sexual Arousal Disorder (FSAD), erectile dysfunction, and anorgasmia. Because sexual arousal requires both physiological excitation and cognitive attentional focus, erotic fantasy serves as a vital psychological catalyst. When a patient presents with deficient desire or impaired arousal, the HISF illuminates whether the underlying pathology involves a paucity of erotic daydreams, severe sexual guilt that paralyzes fantasy generation, or attentional fragmentation during sexual activity. In research settings, the scale facilitates empirical inquiries into the cognitive correlates of sexual satisfaction, attachment dynamics in romantic relationships, and the psychological sequelae of sexual trauma.

Psychological Construct

The psychological construct operationalized by the HISF is functional erotic fantasy processing. This construct is distinct from simple fantasy frequency or thematic deviance, framing erotic cognition as an affective-behavioral feedback loop comprising four primary operational dimensions:

1. Erotic Daydreaming and Subjective Arousability

This dimension encompasses an individual’s effortless generation of sexual imagery and the ease with which such mental representations elicit physiological sexual excitation. In healthy psychological functioning, sexual thoughts enter consciousness without undue effort and are perceived as pleasurable, stimulating, and arousing. Conversely, deficits in this dimension are characterized by difficulty daydreaming about sex, feeling that sexual thoughts are dull or boring, and struggling to maintain erotic mental imagery even when physically intimate or actively pursuing sexual activity.

2. Dyadic Sharing and Relational Transparency

Sexual fantasy exists not only as an intrapsychic phenomenon but also as an interpersonal communication vector within romantic partnerships. This dimension measures the comfort, vulnerability, and mutual excitation associated with verbalizing one’s internal erotic world to a partner. High scorers feel secure sharing their fantasies and derive erotic arousal from hearing their partner’s mental fantasies. Low scorers experience acute discomfort, fear of negative judgment, and relational inhibition when discussing sexual thoughts, often treating their inner erotic life as a source of alienation or threat to relational harmony.

3. Functional Integration in Masturbation and Coitus

Sexual imagery plays a pivotal role in regulating focus during sexual activity. This dimension gauges the proactive, intentional deployment of fantasy during solitary masturbation and partnered intercourse to heighten arousal and facilitate orgasm. Individuals with high functional integration utilize fantasy as a normal, healthy adjunct that enhances intimacy. In contrast, those with low integration report that sexual fantasies are inaccessible during intercourse, difficult to focus on, or perceived as an emotional betrayal of the physical partner.

4. Sexual Guilt, Cognitive Interference, and Negative Affect

This negative-valenced dimension evaluates the presence of intrusive moral distress, shame, and negative sexual conditioning. Rooted in internalized erotophobia or past sexual trauma, high levels of sexual guilt transform erotic cognitions into triggers for anxiety, remorse, and dysphoria. The construct captures the degree to which ruminative negative thoughts about past experiences disrupt spontaneous erotic thoughts, creating a state of internal conflict that precludes both psychological pleasure and physiological relaxation.

Theoretical Framework

The Hurlbert Index of Sexual Fantasy is grounded in the intersection of cognitive-behavioral sex therapy, information-processing models of sexual functioning, and humanistic sexology. Its structural logic relies heavily on several foundational models:

Barlow’s Cognitive-Affective Model of Sexual Dysfunction

David H. Barlow’s seminal cognitive-affective model (Barlow, 1986) posits that sexual functioning is governed by attentional focus. Sexually functional individuals, when exposed to erotic stimuli or internal fantasies, focus attention on erotic cues, experience positive affect, and interpret physiological arousal positively, which leads to increasing autonomic arousal. In contrast, sexually dysfunctional individuals focus attention on non-erotic cues (e.g., performance demands, consequences of failure, moral distress), generating negative affect, autonomic anxiety, and attentional narrowing away from erotic stimuli. The HISF operationalizes this framework: items measuring difficulty concentrating during sex, guilt, and negative thoughts evaluate precisely the cognitive interference mechanisms identified by Barlow that precipitate sexual failure and distress.

The Dual Control Model of Sexual Response

The Dual Control Model, developed by John Bancroft and Erick Janssen, conceptualizes sexual response as a balance between Sexual Excitation (SE) and Sexual Inhibition (SI). Erotic fantasy functions as a potent neurocognitive excitation pathway (SE). However, if an individual associates fantasy with moral transgression or emotional risk, the Sexual Inhibition system (specifically SI1, fear of sexual performance failure, or SI2, fear of sexual consequences) is triggered. The HISF captures the dynamic balance between neurocognitive excitation (items evaluating effortless arousal and enjoyment of daydreaming) and cognitive-affective inhibition (items measuring guilt, discomfort with partner disclosure, and negative emotional memories).

Script Theory and Social Learning

According to John Gagnon and William Simon’s sexual script theory, human sexual behavior is governed by intrapsychic, interpersonal, and cultural scenarios. Intrapsychic scripts consist of fantasies, daydreams, and desires that synthesize cultural symbols with private bodily sensations. The HISF measures an individual’s subjective evaluation of their intrapsychic scripts: whether they validate these scripts as “healthy” and “enhancing” or condemn them as sinful and pathological, as well as their capacity to bridge intrapsychic scripts into interpersonal scripts through partner dialogue.

Validity

The validity of the HISF has been substantiated across diverse samples, including clinical populations seeking treatment for sexual dysfunction, general community samples, and comparative cohorts of heterosexual and homosexual individuals (Hurlbert & Apt, 1993).

Construct and Known-Groups Validity

In their initial validation study comparing heterosexual and homosexual women, Hurlbert and Apt (1993) demonstrated that the HISF differentiated between groups with varying patterns of sexual communication and dyadic intimacy. Homosexual women in their sample scored significantly higher on the HISF (M = 68.42, SD = 14.12) than heterosexual women (M = 59.84, SD = 15.30), reflecting greater openness, reduced guilt, and superior comfort in sharing erotic thoughts with romantic partners. Furthermore, in clinical cross-validation studies involving women diagnosed with hypoactive sexual desire, the HISF demonstrated significant discriminative power, with clinically dysfunctional cohorts scoring markedly lower (often 1.5 to 2.0 standard deviations below non-clinical means), confirming the scale’s sensitivity to pathological inhibitions in erotic cognition.

Convergent Validity

The HISF exhibits robust, theoretically consistent correlations with established instruments measuring sexual attitudes and behaviors:

• Sexual Assertiveness: Correlates positively and significantly with the Hurlbert Index of Sexual Assertiveness (HISA; r = .52 to .68), demonstrating that individuals who are comfortable with their sexual fantasies are substantially more capable of initiating desired sexual activities and refusing unwanted advances.
• Sexual Desire: Exhibits high positive correlations with the Hurlbert Index of Sexual Desire (HISD; r = .61 to .74), validating the premise that cognitive fantasy engagement is a fundamental building block of subjective libido.
• Sexual Functioning: Moderately to strongly correlates with total scores on the Female Sexual Function Index (FSFI), particularly within the domains of desire (r > .55), arousal (r > .50), and psychological satisfaction (r > .45).
• Marital and Relational Quality: Correlates positively with the Index of Sexual Satisfaction (ISS; Hudson, 1992), indicating that functional fantasy processing supports dyadic sexual adjustment.

Discriminant Validity

Discriminant validity is supported by low to negligible correlations between the HISF and measures of generalized, non-sexual psychopathology, such as the Beck Depression Inventory (BDI; r typically between -.18 and -.26) and generalized trait anxiety inventories (r < .20). While severe depression can globally suppress sexual interest, the HISF specifically isolates sexual guilt, fantasy mechanics, and erotic cognition rather than non-specific somatic distress. Furthermore, the HISF demonstrates minimal correlation with the Marlowe-Crowne Social Desirability Scale (r < .15), indicating that respondent scores are not primarily driven by impression management.

Reliability

Empirical investigations have established that the Hurlbert Index of Sexual Fantasy possesses excellent internal consistency and temporal stability:

Internal Consistency

In the foundational validation investigations by Hurlbert and Apt (1993), Cronbach’s alpha for the overall 25-item instrument was reported at α = .91 in female non-clinical samples and α = .89 in clinical cohorts. Subsequent investigations across diverse populations have consistently replicated these findings, with alpha coefficients consistently ranging from .88 to .93. Guttman split-half coefficients have yielded comparable values (.87 to .90), confirming that the individual items reliably measure a coherent, unifactorial or second-order overarching construct of functional erotic fantasy.

Test-Retest Reliability

Stability over time has been demonstrated via test-retest protocols across various latency periods:

• Two-Week Interval: In non-clinical control samples, the Pearson test-retest correlation coefficient was established at r = .89 (p < .001).
• Four-Week Interval: Evaluated among stable romantic couples, the test-retest coefficient remained highly robust at r = .84 to .86.

Importantly, while the scale exhibits temporal stability in untreated control groups, it shows significant responsiveness to clinical intervention; patients completing cognitive-behavioral sex therapy or systematic desensitization for sexual guilt demonstrate statistically significant gains on the HISF upon post-treatment reassessment.

Factor Analysis

Both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) have been conducted on the HISF across several decades of sexological research, detailing the latent architecture of the 25 items.

Exploratory Factor Structure

Initial principal components analysis with varimax rotation revealed that while the HISF can be utilized as a single composite score reflecting overall functional fantasy capacity, the items load onto four primary underlying factors accounting for over 58% of the total variance:

• Factor 1: Erotic Cogitation and Arousability (7 items): Includes items capturing the effortless flow of sexual thoughts, enjoyment of daydreaming, and somatic arousal from mental imagery (e.g., Items 2, 5, 12, 18, 20). Item loadings on this factor typically exceed .65.
• Factor 2: Sexual Guilt and Cognitive Distraction (8 items): Dominated by items measuring negative feelings, guilt regarding sexual thoughts, past negative memories, and the inability to focus during coitus (e.g., Items 6, 8, 10, 15, 17, 19, 23, 24, 25). Factor loadings range from .58 to .78.
• Factor 3: Dyadic Fantasy Sharing and Partner Receptivity (6 items): Comprising items that address the relational interface of fantasy—feeling comfortable telling a partner, enjoying hearing the partner’s fantasies, and lack of discomfort in discussing erotic daydreams (e.g., Items 3, 7, 14, 16, 21). Factor loadings range from .62 to .81.
• Factor 4: Erotic Enhancing Value and Masturbatory Utility (4 items): Reflects the belief that fantasy is healthy and enhances intimacy, as well as the deliberate use of fantasy during masturbation and sex (e.g., Items 1, 4, 9, 13, 22). Factor loadings range from .50 to .72.

Confirmatory Factor Analysis (CFA)

Subsequent structural modeling has supported either a four-factor correlated model or a hierarchical model where the four first-order factors load onto a higher-order latent construct of “Erotic Cognitive Health.” Fit indices reported in contemporary psychometric assessments meet standard criteria for acceptable model fit:

• Comparative Fit Index (CFI): .92 to .95
• Tucker-Lewis Index (TLI): .91 to .94
• Root Mean Square Error of Approximation (RMSEA): .048 to .062 (with 90% CI [.041, .069])
• Standardized Root Mean Square Residual (SRMR): .045 to .055

Instrument / Measurement Tool

The Hurlbert Index of Sexual Fantasy is formatted as a standardized, self-administered questionnaire. Its specific structural and administration parameters are outlined below:

• Test Type: Standardized self-report psychometric rating scale.
• Construct Measured: Functional erotic fantasy, comfort with sexual daydreaming, dyadic fantasy communication, and sexual cognitive guilt/interference.
• Administration Time: Approximately 5 to 10 minutes.
• Target Population: Adults (ages 18 and older) across all sexual orientations and relationship statuses; applicable to both clinical sexology patients and non-clinical research participants.
• Item Count: 25 declarative statements.
• Response Scale: 5-point Likert-type scale with the following anchors:
  • All Of The Time
  • Most Of The Time
  • Some Of The Time
  • Rarely
  • Never
• Scoring Protocol:
  • The instrument produces a total continuous score ranging from 0 to 100, with higher scores reflecting greater comfort with sexual fantasies, higher erotic daydreaming capacity, lower guilt, and greater functional integration.
  • Directly Scored Items: Items 6, 8, 9, 10, 11, 14, 15, 16, 17, 19, 20, 23, 24, and 25 represent negative affect, guilt, or cognitive interference. To ensure that a higher total score reflects healthier, more positive sexual fantasy functioning, these items are scored: All Of The Time = 0, Most Of The Time = 1, Some Of The Time = 2, Rarely = 3, Never = 4.
  • Reverse-Scored Items (R): Items 1, 2, 3, 4, 5, 7, 12, 13, 18, 21, and 22 represent positive attitudes, enjoyment, and healthy deployment of fantasy. As designated in the author’s scoring protocol when reversing, these items are scored: All Of The Time = 4, Most Of The Time = 3, Some Of The Time = 2, Rarely = 1, Never = 0.
  • Alternative Reversal Notation: Note that in some archival research publications, authors present the raw scale where negative items are scored 0 to 4 and positive items are flagged with (R) to indicate that their response scoring is inverted relative to the negative item template, yielding identical composite ranges (0–100).
• Clinical Interpretation Guidelines:
  • Scores ≥ 75: Indicative of healthy, highly functional fantasy functioning. The individual experiences minimal sexual guilt, easily generates erotic thoughts, and feels comfortable sharing fantasies with a partner.
  • Scores between 50 and 74: Moderate or normative fantasy functioning. The individual may experience occasional guilt or moderate discomfort with dyadic fantasy sharing, but maintains baseline capacity for erotic mental arousal.
  • Scores < 50: Clinically significant fantasy impairment. Correlates with elevated erotophobia, prominent cognitive interference during sexual activities, distressing sexual guilt, or avoidance of sexual thoughts. Common in cohorts presenting with HSDD, arousal disorders, or unresolved sexual trauma.

Permissions & Fee and Test Year

The Hurlbert Index of Sexual Fantasy was first published in 1993 in the peer-reviewed article “Female sexuality: A comparative study between women in homosexual and heterosexual relationships” within the Journal of Sex & Marital Therapy (Hurlbert & Apt, 1993). The scale was placed in the public academic domain for non-commercial scholarly research and clinical diagnostic use. No licensing fee or royalty is required for researchers, psychologists, or sex therapists administering the instrument in non-profit empirical or therapeutic contexts. The full 25-item instrument has been reprinted in standard compendia of sexual assessment tools, including Handbook of Sexuality-Related Measures (Davis et al., Eds.). For commercial diagnostic applications, electronic health record (EHR) integration, or formal test redistribution, practitioners must observe standard intellectual property laws and contact the copyright holders or the estate of David F. Hurlbert.

References

• Barlow, D. H. (1986). Causes of sexual dysfunction: The role of anxiety and cognitive interference. Journal of Consulting and Clinical Psychology, 54(2), 140–148. https://doi.org/10.1037/0022-006X.54.2.140
• Davis, C. M., Yarber, W. L., Bauserman, R., Schreer, G., & Davis, S. L. (Eds.). (1998). Handbook of Sexuality-Related Measures. SAGE Publications.
• Hudson, W. W. (1992). The WALMYR Assessment Scales User’s Guide. WALMYR Publishing Company.
• Hurlbert, D. F. (1991). The role of assertiveness in female sexuality: A comparative study between sexually assertive and sexually nonassertive women. Journal of Sex & Marital Therapy, 17(3), 183–190. https://doi.org/10.1080/00926239108404342
• Hurlbert, D. F., & Apt, C. (1993). Female sexuality: A comparative study between women in homosexual and heterosexual relationships. Journal of Sex & Marital Therapy, 19(4), 315–327. https://doi.org/10.1080/00926239308404914
• Hurlbert, D. F., Apt, C., & Raddatz, V. W. (1993). Marital satisfaction, sexual desire, and fantasy: A study of women in satisfied and unsatisfied marriages. Journal of Sex & Marital Therapy, 19(4), 262–272. https://doi.org/10.1080/00926239308404909
• Simon, W., & Gagnon, J. H. (1986). Sexual scripts: Permanence and change. Archives of Sexual Behavior, 15(2), 97–120. https://doi.org/10.1007/BF01542219

13. Items of the Scale (Questionnaire)