Effect of aversive classical conditioning on sexual response in women with dyspareunia

Dyspareunia, a persistent or recurrent genital pain associated with sexual
intercourse is hypothesized to be related to diminished sexual arousal. An
explanatory model, described by Spano & Lamont (1975), assumes that in women
with dyspareunia the experienced pain during vaginal penetration, or memories
of that pain, lead to fear of pain in new intercourse situations. That fear
may, in turn, result in diminished sexual arousal and diminished vaginal
lubrication.
Only a few studies directly investigated genital response in women with sexual
pain disorders. Brauer, Laan, and ter Kuile (2006) observed, in a study in
women with and without dyspareunia, diminished genital arousal in response to
erotic film presented in a threatening experimental context. These results
indicate that threat of pain inhibits sexual responding in women. Based on
these findings, it is hypothesized that when sexual stimuli are associated
repeatedly with (threat of) pain as in the case of dyspareunia, a learned
aversive response may be acquired through classical conditioning, which
subsequently may result in diminished genital and subjective sexual response to
erotic stimulation. A stronger aversive conditioning effects on sexual response
is expected in women with dyspareunia than in controls due to an already
learned association of sex and pain in these women. Evidence for prior aversive
conditioning in dyspareunia patients might be a stronger magnitude or a delayed
extinction of experimental conditioning effects.

The purpose of the present study is to clarify the assumed role of fear in
women with superficial dyspareunia. The hypothesis will be tested that aversive
conditioning in women with dyspareunia and control women will lead to
diminished sexual response. It is expected that pairing of an erotic stimulus
(the CS+) with a pain stimulus will lead to less genital arousal, less
subjective sexual arousal, and stronger negative affect in response to this
erotic stimulus, and that these effects will be stronger in women with
dyspareunia.

A differential conditioning design is applied, in which women are presented
with two erotic stimuli, of which only one (the CS+) is followed by an aversive
unconditioned stimulus (US). As aversive US an electric pain stimulus to the
left wrist will be applied. During a pre-conditioning, conditioning, and
post-conditioning phase women will view two erotic pictures repeatedly, while
genital sexual arousal is assessed as vaginal pulse amplitude using vaginal
photoplethysmography (dependent variable). Self-reported ratings of emotional
valence and subjective sexual arousal (dependent variables) are collected
during the pre-conditioning and post-conditioning phase.

Participants will visit the LUMC twice. The screeningsvisit will take 2 hours
and the psychophysiological measurements will take 1 hour.
The questionnaires on sexual functioning, (self)insertion of the
photoplethysmograph, viewing of erotic pictures, and/or the applied painstimuli
may be experienced as unpleasant.
The vaginal photoplethysmograph used in this study is a safe device. No harmful
events have been reported. The pain stimulus apparatus is protected from any
potential power surges or electrical malfunctioning. From other studies
(Janssen, 1998) and a pilot study (Both et al., in preparation) it is known
that pain stimuli with the length/duration and strength brought about by a pain
stimulus device will not cause harm. Moreover, the intensity of the pain
stimulus will be individually adjusted. Preceding the pre-conditioning phase
pain stimuli will be applied in increasing intensity. The participant will be
instructed to indicate which intensity of the pain stimulus is experienced as
*unpleasant and demanding some effort to tolerate*. The pain stimulation will
then be set on the indicated level of intensity.