What makes people help others, and why do bystanders often fail to help in an emergency?
Explain prosocial behaviour and the bystander effect, including the factors that increase or decrease helping, with reference to Latane and Darley
WACE Year 12 Psychology Unit 4: prosocial behaviour, altruism, the bystander effect, diffusion of responsibility and pluralistic ignorance, and Latane and Darley's decision model and research on helping.
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What this dot point is asking
SCSA asks you to define prosocial behaviour and altruism, explain the bystander effect and its causes, describe Latane and Darley's research and decision model, and list the factors that raise or lower helping. The marked skill is naming the step at which helping breaks down.
Prosocial behaviour and altruism
Prosocial behaviour is any action intended to benefit another person, such as helping, sharing, comforting or cooperating. Altruism is a specific form of prosocial behaviour: helping motivated by concern for others with no expectation of personal reward. Prosocial behaviour can be encouraged by empathy, social norms (the norm of reciprocity, the norm of social responsibility) and learned through reinforcement and modelling.
The bystander effect
The bystander effect is the counterintuitive finding that an individual is less likely to help a victim when other people are present, and that helping decreases as the number of bystanders increases. It was studied after the widely reported case in which a woman was attacked while many neighbours apparently failed to intervene.
Two main processes explain it.
- Diffusion of responsibility: when others are present, each person feels less personal responsibility to act, assuming someone else will.
- Pluralistic ignorance: in an ambiguous situation, people look to others to judge whether it is an emergency; if everyone appears calm, each concludes nothing is wrong.
Latane and Darley's decision model
Bibb Latane and John Darley proposed that helping depends on passing through five sequential steps, and failing any one stops help.
- Notice the event.
- Interpret it as an emergency (where pluralistic ignorance can block help).
- Take personal responsibility (where diffusion of responsibility can block help).
- Decide how to help (knowing what to do).
- Provide help (which may be blocked by fear or cost).
Their experiments supported this. In one, participants who believed they were the only witness to a staged seizure helped far more often and faster than those who believed several others were also present, confirming diffusion of responsibility.
Factors affecting helping
Helping increases when the bystander notices the event, sees it clearly as an emergency, feels responsible (for example as the only witness), has the competence to help, knows the victim or sees similarity, and when the perceived cost of helping is low. Helping decreases with more bystanders, ambiguity, high personal cost or danger, and time pressure.
Why this matters
Understanding the bystander effect informs first-aid and safety training, which teaches people to assign responsibility directly (pointing to one person and asking them to call for help) to overcome diffusion of responsibility. It also links back to group influence, since both rest on diffusion of responsibility.