A group recalling together produces less than the same number of people recalling separately and pooling the results.
Weldon and Bellinger compared real groups against nominal groups of individuals whose non-overlapping recall was combined on paper. The nominal groups won. The proposed cause is retrieval disruption: hearing another member's account interferes with one's own retrieval strategy, so each person recalls less than they would have alone.
In practice
- A team debrief captures less than the same four people would have written down separately before speaking.
- A family reconstructing a holiday together remembers fewer episodes than the sum of what each could have listed.