What are some biological factors linked to infidelity?

• A. High serotonin and oxytocin
• B. Deficiencies in dopamine receptors and high testosterone levels in men.
• C. Low testosterone in men.
• D. Increased estrogen

Answer: (B)

The main idea here is that biology can influence how people pursue sexual variety and how rewarding sexual experiences feel. Dopamine pathways govern reward, motivation, and novelty seeking. If dopamine receptor function is lower or less responsive, sexual rewards can feel less satisfying, which can push someone to seek out additional or more intense experiences to achieve the same level of reward. On the other hand, testosterone in men is closely tied to mating drive, confidence in pursuing sexual opportunities, and tolerance for risk in pursuit of partners. Higher testosterone is often linked to greater mating effort and a preference for variety, which can manifest as infidelity in certain contexts.

Putting those together, deficiencies in dopamine receptors plus high testosterone create a profile where the motivational drive for novelty and the drive for sexual variety are both elevated, making infidelity more likely in some individuals, especially when other factors like relationship satisfaction or opportunity align. It’s important to remember that these are associations, not guarantees—relationship dynamics, values, mental health, and social context all shape behavior and outcomes.

The other options don’t fit as well because high serotonin and oxytocin promote bonding and trust, not infidelity; increased estrogen or low testosterone in men doesn’t align as consistently with higher risk of seeking multiple partners.