Darley and Latane hypothesized two factors that may influence bystanderism:

  1. Diffusion of responsibility
  2. Social influence
  • Diffusion of Responsibility

“Someone else will help.” This is one thought that might be a result of diffusion of responsibility. To diffuse means to spread something widely, so if there are more people around the responsibility of helping is spread amongst those people so individuals feels less direct responsibility for helping. So the more people there are around to help, the less likely any will help.

  • Social Influence

Humans are naturally social creatures and we’re heavily influenced by the actions of others. In situations of uncertainty, we tend to look to others for information on how to behave. Many emergency situations begin ambiguously, i.e. it is not clearly apparent that it is an emergency so we may look to others for cues. In situations where someone requires help, if other around are not helping then we may not help either.

There are two types of social influence that have been termed by social psychologists normative and informational social influence. You can read more about those here.

Supporting Studies

Smokey Room

In this experiment participants sat in a waiting room and filled out a questionnaire on life as a student. After completing two pages of the questionnaire, the room slowly filled with smoke that was puffed through an air vent. By the time the participant would have finished filling out the survey, visibility was impaired due to the smoke in the room. The results were:

  1. Participants alone reported the smoke 75% of the time.
  2. Participants in groups of 3 reported the smoke 38% of the time.
  3. Participants with two passive confederates reported the smoke 10% of the time.

Researcher Collapsing

In this experiment participants were again filling out a questionnaire and then as the female researcher left the room they heard a crash, the sound of a body falling and the moaning of someone in pain. The results were similar to those above.

  1. Alone = 70% of people helped
  2. Groups of 3 = 40% helped
  3. One passive confederate = 7% helped

Participant Collapsing

In this experiment individual participants were put in soundproof rooms with headphones and microphones. They were lead to believe that the researchers were researching about personal problems of students and that they were alone with one other student or with four other students taking part in the experiment at the same time. They were in individual rooms, so they couldn’t see the other students but could hear them through their headsets. There were actually no other participants, however, they were just tape recordings. The participants heard the recordings of the other students, the first of which said they suffered from seizures sometimes. The real participant spoke last and as they spoke, the first student was heard again and started complaining and it appeared as if they were having a seizure. They then choked and went silent.

  1. When alone participants sought help:
    1. 85% by 2 minutes, 100% by 6 minutes
  2. When believing there were four other people hearing the suffering student:
    1. 31% by 2 minutes, 62% by six minutes.