Psychology of Aggression and Prosocial Behavior

  • Explanations for Aggression

    • Instinct and Evolution Explanations

    • Freud's View: Aggression is a basic human instinct, linked to "Thanatos" or the death instinct.

    • Modern Psychodynamic Psychologists: Most do not accept Freud's original theory but still view aggression as a behavioral potential that individuals are born with, typically activated by frustration and anger.

    • Parenting Task: Teaching young children to control aggressive impulses (e.g., toddlers biting, kicking, throwing tantrums) is a fundamental parenting task, reflecting the need for societies to inhibit aggression.

    • Evolutionary Theorists' View: Aggression is adaptive for survival and reproductive value.

      • Cross-Species Observation: Aggression (including intra-species killing) occurs in all animals.

      • Male Aggression: Typically directed at other males for access to females and to maintain territory.

      • Female Aggression: Primarily elicited by attacks on their young.

      • Human Evolution: Like other animals, humans are believed to have evolved aggressive mechanisms activated when survival or reproductive success of kin is threatened.

  • Biological Explanations for Aggression

    • If aggression is part of being human (instinctual/evolutionary views), then it must involve the nervous or endocrine systems.

    • Genetics:

    • Selective Breeding: Research shows highly aggressive mice, rats, or rabbits can be selectively bred; observed in certain dog breeds (bred for aggression/killing).

    • Twin and Adoption Studies: Aggression can be heritable, up to approximately the 50\% mark when comparing monozygotic and dizygotic twins.

    • Nervous System:

    • Limbic System and Hypothalamus: Involved in emotional reactions and drive states.

    • Prefrontal Cortex: Involved in decision-making and organization; damage or developmental delay in this area can lead to increased aggression.

    • Hormones: Play a substantial role in aggressive tendencies.

    • Testosterone: Males claim social dominance and may become aggressive if this status is threatened. Higher testosterone levels are correlated with impatience and irritability.

    • Bidirectional Correlation: Testosterone may increase aggression, but aggressive behavior can also increase testosterone levels.

  • Environmental Explanations for Aggression

    • Frustration-Aggression Hypothesis:

    • Proposed by Dollard et al. (1939): Aggression results from the failure to achieve a goal.

    • Process: Individuals set daily goals (e.g., good grades, morning routine), and the inability to achieve them leads to frustration, which then elicits aggression.

    • Example: Inability to find keys leads to frustration, resulting in a short or aggressive response to others.

    • Scapegoating (Displacement): When direct challenge to frustration is not possible, aggressive behavior may be diverted to another target (e.g., pushing a chair, slamming a door instead of throwing a phone when the battery is flat).

    • Limitations: Not all aggression results from frustration, and not all frustration leads to aggression. Other responses to frustration can include depression or increased motivation.

    • Cognitive Neo-Association Theory (Berkowitz):

    • Extension of Frustration-Aggression: Frustration breeds aggression to the extent that it elicits an unpleasant emotion.

    • Mechanism: Unpleasant situations (e.g., non-smoker near a smoker in a confined area) lead to negative affect and physiological arousal (e.g., bad mood, disgust, headache), which can trigger aggression.

    • Aversive Situations: Besides noxious odors (like smoking), heat, hostility, and insults can also lead to negative emotions and aggression.

    • Heat and Aggression: As temperatures rise, tempers tend to rise. Strong correlations exist between hot weather, riots, and aggressive criminal behavior (assault, rape, murder) during summer months.

    • Cognitive Activation: Regardless of the source of arousal (hot weather, insults, odors), negative emotions activate similar cognitions stored in memory, making it difficult to suppress negative emotions.

    • Environmental Cues:

    • Presence of Weapons: The mere presence of weapons in the environment can stimulate aggressive behaviors.

    • Aggressive Scripts: Weapons are primarily associated with aggression and violence, leading to the development of aggressive mental