Domain B · Learning & development

How a cue acquires erotic value

This is the domain with actual experiments. They show that sexual arousal is conditionable. They do not, yet, show that this is how podophilia happens in the wild, and they do not explain the foot differential.

Classical conditioning of sexual arousal

Mechanism: A conditioned stimulus (CS) that reliably precedes an unconditioned erotic stimulus (US) comes to elicit genital arousal on its own. Boots were the CS in the founding human demonstrations.
Sources: Rachman, S. (1966). Sexual fetishism: An experimental analogue. Psychological Record 16: 293-296. Three men; criterion of five successive responses to a boot slide in 30, 65, and 24 trials; extinction and spontaneous recovery. Rachman, S. & Hodgson, R. J. (1968). Experimentally-induced “sexual fetishism”: replication and development. Psychological Record 18: 25-27. Five men; backward-conditioning control, none to criterion.
Critique: Tiny N, all male, student/analogue sample, weak CRs, rapid extinction. A laboratory boot CR is not a clinical fetish. Plaud and Martini (1999) later conditioned male arousal with better controls; effects remain modest relative to nonhuman work.
Open questions: Would a foot photograph, as CS, condition more readily than a matched hand photograph in unselected men? Unrun, or at least unpublished at scale.
Cross-links: B3, B4, C4, E1.

Grade note: the existence of human sexual conditioning is supported by several labs (E1-ish as a class). The 1966/1968 papers themselves are E2. The leap to natural-life etiology is E3.

Operant reinforcement and orgasm pairing

Mechanism: Once a foot-related stimulus is even slightly arousing, masturbation to orgasm in its presence should strengthen the association. McGuire, Carlisle and Young (1965) proposed masturbatory conditioning as a general path into sexual deviation.
Sources: McGuire, R. J., Carlisle, J. M. & Young, B. G. (1965). Sexual deviations as conditioned behaviour. Behaviour Research and Therapy 3. Later covert-sensitization and orgasmic-reconditioning literatures assume the same lever, usually in treatment rather than etiology.
Critique: Almost no prospective evidence that this sequence originates podophilia rather than maintaining it. Circular if the first arousal is unexplained. Ethical limits on experimental orgasm-pairing in naïve subjects are real.
Open questions: Experience-sampling in people who already have the interest: does orgasm frequency to foot cues predict later cue potency?
Cross-links: B1, E3, E4. Stronger as a maintenance story than as etiology.

Awareness and biological relevance of the CS

Mechanism: Conditioning may not require conscious CS-US awareness. Sexually relevant CS (an abdomen) may condition more readily than an irrelevant CS (a gun), at least when subliminal; with conscious CS, Hoffmann et al. found a sex difference.
Sources: Hoffmann, H., Janssen, E. & Turner, S. L. (2004). Classical conditioning of sexual arousal in women and men: effects of varying awareness and biological relevance of the conditioned stimulus. Archives of Sexual Behavior 33: 43-53. 27 women, 29 men, plus unpaired controls. First clear genital CR in women in this design. Both sexes conditioned more to abdomen than gun when CS was subliminal.
Critique: The relevant CS was an abdomen, not a foot. If ‘relevance’ matters, feet should be harder to condition than bodies unless some other factor (adjacency, culture, concealment) makes feet relevant. Conscious-CS women conditioned to the gun, attributed to autonomic arousal (skin conductance), a complication.
Open questions: A Hoffmann-style design with foot vs hand vs abdomen as CS in people without the fetish.
Cross-links: B1, A1, C1.

Field conditioning in couples

Mechanism: A novel scent worn during partnered sex (CS+) versus during nonsexual togetherness (CS−) can acquire genital response in men when later tested in the lab.
Sources: Hoffmann, H., Peterson, K. & Garner, H. M. (2012). Field conditioning of sexual arousal in humans. Socioaffective Neuroscience & Psychology 2: 17336. Seven experimental heterosexual couples, seven controls, two weeks. Male genital CR to CS+ increased; affective preference for CS− trended down (possible inhibitory learning).
Critique: Very small N; CR not larger than laboratory effects, contrary to the hope that ‘real US’ would dwarf film clips. Still the best ecological demonstration that human sexual conditioning is not a lab toy.
Open questions: Could a visual foot cue, rather than an odor, be trained in the same field design? Unrun.
Cross-links: B1, C4.

Who conditions? Individual differences

Mechanism: People may differ in sexual conditionability. Traits of sexual excitation (SES) and inhibition (SIS) are hypothesized to predict excitatory versus inhibitory learning, in the spirit of Gray’s BIS/BAS.
Sources: Hoffmann, H. (2025). Individual differences in excitatory and inhibitory sexual conditioning in humans. Archives of Sexual Behavior. Field training with essential-oil CSs and masturbation; medium-to-large CE/CI effects on affect in female-bodied participants; genital CE in both sexes. Hoffmann, Goodrich, Wilson & Janssen (2014, Sexual Addiction & Compulsivity): pilot, MSM high vs low sexual compulsivity, trend toward greater conditionability in the high group.
Critique: Replications are young. Even if conditionability is a trait, it explains who learns, not what is learned.
Open questions: Does SES predict laboratory conditioning to a foot CS specifically?
Cross-links: A7, C5, B1.

Sexual imprinting and the lovemap

Mechanism: John Money’s lovemap is a developmental template of the idealized lover and script, formed after birth, manifest after puberty, and capable of being ‘vandalized’ into paraphilia by trauma, neglect, or a nonsexual childhood event that induced genital arousal. Fetishistic/talismanic paraphilias are one of his six classes.
Sources: Money, J. (1986). Lovemaps. Irvington. Money, J. & Lamacz, M. (1989). Vandalized Lovemaps. Prometheus. Term used from ~1980 (“Pairbonding and limerence”).
Critique: Retrospective, richly named, weakly tested. Critical-period talk is borrowed from ethology without the corresponding deprivation experiments in humans. Money’s clinical authority is historically compromised by the Reimer case; that does not automatically falsify every construct, but it bars deferential citation. Mixed empirical support is the right phrase.
Open questions: Any prospective, pre-registered test of a childhood window for fetish acquisition? Not found.
Cross-links: B7, C4 (Kendrick cross-fostering in goats/sheep is the animal imprinting analogue), H1.

First-experience self-reports

Mechanism: People often narrate a first pairing: a pubertal glimpse of a shoe, a foot massage, a peer dare, a parental scene. In Weinberg’s organization sample those remembered experiences clustered around puberty and were mostly positive, with same-age peers the most common source. Restrictive upbringing and social isolation, once hypothesized as preconditions, were not typical.
Sources: Weinberg, M. S., Williams, C. J. & Calhan, C. (1995). “If the shoe fits…”: Exploring male homosexual foot fetishism. Journal of Sex Research 32: 17-27. Companion: Weinberg, Williams & Calhan (1994). Homosexual foot fetishism. Archives of Sexual Behavior 23: 611-626. N = 262, Foot Fraternity.
Critique: Autobiography after the fact. Memory reconsolidates around a current identity. Without contemporaneous records, these reports are data about narrative, not about cause. The sample is gay/bisexual men in a fetish organization.
Open questions: Could any cohort study collect nonsexual foot-exposure items at age 12 and sexual items at 25? In principle yes; in practice unfunded.
Cross-links: B6, B8, E6.

Tickling and early somatosensory play

Mechanism: Community lore treats childhood foot tickling, or being sat upon, as a proto-erotic script later sexualized. Power, laughter, restraint, and the foot coincide.
Sources: No controlled developmental study was found. The motif appears in first-person internet accounts and in some clinical anecdotes.
Critique: Tickling is common; the fetish is not. A near-universal childhood event cannot, without additional selectors, explain a minority adult outcome.
Open questions: Base rates of recalled foot-tickling in people with and without podophilia, with a non-foot tickling control item.
Cross-links: B7, A6, H4 (D/s overlay).

Confidence, Domain B

Solid: sexual arousal is conditionable in men and women; real-world pairing can do it; animals show still stronger effects. Contested: how much of adult podophilia is that process. Unknown: the first pairing, the window, and the selector that makes the CS a foot. For etiology this domain is the strongest we have. For specificity it is almost silent.