Stressor 1: TEMPERATURE
Explaining the relationship
A01: Indirect links (Routine activity theory)
People behave differently in summer (Change of routine: outside more, more alcohol consumed) and thus become more aggressive.
A02: However... although this 'indirect' explanation can explain naturalistic studies, it does not explain laboratory studies that show temperature as a causal factor.
A01: Direct links (negative affect escape)
Negative affect (mood) increases with temperature. At high heat levels, aggression occurs if escape is not possible.
A02: However... some studies show a curvilinear relationship between heat and aggression but others (e.g. ANDERSON and ANDERSON 1984) haven't found a decline in aggression at very high temperatures.
Research studies of temperature as a stressor
A01: Heat and Frustration
(KENRICK and MACFARLANCE, 1986) Drivers responded more aggressively to frustration when heat levels were high.
A01: Heat and Violent crime
(ANDERSON, 1987) Archival records show violent crimes are more common in hotter years and hotter quarters of the year.
The relationship could be biological, as heat activates the ANS and causes increased testosterone, leading to aggression. Also explains why males are more aggressive.
- Naturalistic studies provide only correlational data
- Other variations that may lead to aggression are uncontrolled.
Stressor 2: NOISE
A01: Explaining the relationship:
Noise alone is not believed to cause aggression, but when combined with pre-existing anger, may trigger aggressive behaviour.
A02: This can be understood by... seeing noise as being like any other stressor. It increases ANS activity, and predisposes people to aggressive behaviour.
- Laboratory studies: GEEN and O'NEAL (1969) found that loud noise increases aggressiveness; DONNERSTEIN and WILSON (1976) found that levels of aggression decrease if people believe they have some control over noise.
- Exposure to aircraft noise: EVANS et al. (1998) found that long-term exposure to aircraft noise caused increase in blood pressure and stress hormones in children.
A02: This can be explained by... the fact that aircraft noise may cause tiredness, which was what caused children to behave aggressively, rather than noise itself.
Stressor 3: CROWDING
A01: Explaining the relationship
Crowding may create arousal (and hence aggression) because of insufficient personal space and diminished sense of control.
A02: A problem is that... the effects of crowding vary with social context (Deindividuation)
A02: However, this relationship disappears when other social factors are controlled (FREEDMAN, 1975)
- Crowding and violent crime: Some studies found a positive correlation between high population density and violent crime (SCHMITT, 1967)
- Crowding and the dance floor: A study of nightclubs found that levels of crowding was related to the number of aggressive incidents (MACINTYRE and HORNEL, 1997)