Summary of Male Sexual Behavior
Learning Objectives
- Explain animal research on male sexual behavior and endocrine correlates
- Understand brain mechanisms involved in male sexual behavior
- Discuss individual and age-related variations in male sexual behavior
Male Sexual Behavior in Animals
- Sexual motivation in males is strong; may risk life for mating opportunities.
- Different mating strategies due to reproductive potential differences:
- Gametes: females have limited eggs, males have abundant sperm.
- Parental investment: females generally invest more in offspring than males.
- Females tend to be choosy, while males are ardent in mating.
Risk-Taking Behavior
- Study findings: male skateboarders took more risks performing tricks in front of females, indicating risk as a sexual display strategy.
Phases of Male Sexual Behavior
- Appetitive Phase: courtship involving species-specific behaviors.
- Consummatory Phase: involves copulation.
- Males spend more energy seeking copulation than in the act itself.
Male Rodent Mating Behavior
- Sexual attraction is mainly olfactory; involves sniffing.
- Typical copulatory sequence: mounting, intromission, ejaculation (20 mounts, 10-15 intromissions).
- Post-ejaculation behavior includes vocalization and self-grooming.
Coolidge Effect
- Novel partner leads to renewed sexual activity after being sexually satiated with a current partner.
Hormonal Influences
- Androgens affect sexual behavior and motivation in males.
- Castration reduces sexual behaviors in a specific order, but testosterone treatment can restore sexual functions.
- Aromatization of testosterone to estradiol impacts mating behavior.
Individual Differences in Mating Behavior
- High drive males not necessarily having higher testosterone levels; variations in behavior persist despite testosterone concentrations.
- Low levels of testosterone can still maintain sexual behavior.
Brain Mechanisms
- Olfactory System: critical for mating attempts.
- Amygdala: processes hormonal regulation and is crucial for appetitive and consummatory behaviors.
- MPOA: integrates multiple stimuli for copulation; activated by mating stimuli.
- Lesions in MPOA disrupt sexual motivation/performance.
Dopamine and Sexual Behavior
- Dopamine levels rise in response to sexual cues, facilitating mating behavior.
- Novel stimuli increase dopamine related to mating activities.
Human Sexual Behavior and Hormones
- Sexual activities in humans peak in early 20s, decline with age.
- T levels correlate with sexual activity.
- Studies indicate that higher testosterone correlates with increased sexual behaviors, but do not directly prove causation.
Treatments for Sexual Dysfunction
- Approximately 50% of men over 40 experience erectile dysfunction.
- Common treatments include Viagra to enhance blood flow to the penis without affecting sexual motivation.