Topic 2: Memory Study Guide

Peterson and Peterson (1959) conducted a laboratory experiment to investigate the duration of short-term memory (STM). Their study aimed to determine how long people can hold verbal information in their STM if they are prevented from rehearsing it. Participants were shown trigrams (meaningless three-letter combinations) and then immediately asked to count backward in threes from a given number. This 'distractor task' was designed to prevent rehearsal. After varying time intervals (ranging from 3 to 18 seconds), participants were asked to recall the trigrams. The findings showed that recall accuracy decreased significantly as the time interval increased, suggesting that information in STM decays rapidly without rehearsal. For instance, after 3 seconds, recall was around 80%, but dropped to less than 10% after 18 seconds. This study provided crucial evidence for the limited duration of STM when rehearsal is stopped, supporting the model of memory that differentiates between STM and long-term memory (LTM).

Bartlett's (1932) 'War of the Ghosts' study is a classic investigation into reconstructed memory. Bartlett argued against the idea that memory is a perfect, passive recording of events. Instead, he proposed that memory is an active process of construction, where individuals interpret and reconstruct past events based on their existing knowledge, beliefs, and cultural schemas. He aimed to demonstrate how cultural background and prior knowledge influence the recall of unfamiliar information. Participants were asked to recall a Native American folk tale, 'The War of the Ghosts', which contained elements unfamiliar to their Western cultural understanding. Over time, their recollections were found to be shorter, more coherent, and distorted to fit their own cultural norms, often omitting or changing unfamiliar details. This study provided early evidence for the psychological concept of reconstructive memory, highlighting how our past experiences and cultural context shape what and how we remember.