Figure 1.

Incentives model reflecting the many reasons to begin a sexual encounter: The brain's appraisal ‘information processing’ of relevant sexual stimuli allows the emotions of arousal and desire to be accessed. Desire ‘drive’ at the outset is advantageous and will reinforce the cycle at many points but its absence does not denote disorder per se. (Reproduced with the permission of Lippincott, Williams and Wilkins from Basson [2001]).