Aggression Most psychologists define aggression as behavior with intent to harm or injure.

Maccoby & Jacklin. “Fairly well-established gender. difference” Maccoby & Jacklin “Fairly well-established gender difference” - For both physical and verbal aggressio - Across cultures - Appeared between 2 and 3 yrs old and continued through college - After that little information available

Janet Hyde – 5% of differences can be attributed to gender Age 6 – 7% of variance College Age – 1% of variance

Sex Differences in US Crime Statistics

Aggression in Pre-School Children

Biological Explanations Testosterone levels Pre-natal hormones Serotonin

Mice data

More Rat data

Bird data

Human data – Correlation Studies

No Correlation – Some studies on men have shown this kind of relationship

Correlation studies in Men High Testosterone levels have been correlated with: - History of arrests 2 studies - History of violent crimes 1 study - Less likely to marry, more to divorce, troubled relations 1 study - Aggressive disposition 2 studies - variety of anti-social behavior AWOL, alcohol & drug abuse 1 study

CAH Girls Activity Level

Serotonin Levels in Violent Suicides

Serotonin Reuptake Inhibitor

Stereotypes Play

Acceptable Male behavior

Big Boys Toys

Movies

Video Games

Sports Images

International Problem Solving