Interference

• Decay is the deterioration of a memory due to lack of maintenance
• Displacement is forgetting through the removal or replacement of a memory due to limited capacity
• Interference is when forgetting occurs due to one memory disrupting or blocking the other
• Retroactive interference is where a new memory disrupts the old one
• Proactive interference is where the old memory disrupts a new one
• Underwood (1957) found evidence to support proactive interference as he gave particpants more and more word lists to recall, each after 24 hours, and the percentage accuracy for the older lists was higher than the new ones
• McGeoch & McDonald showed that similarity in material increased the likelihood of interference occuring
• McGeoch & McDonald split participants into 6 groups and made them all memorize the same list. Then later each group had to memorize a different list, before being asked to recall original list
• McGeoch & McDonald found that the most similar words had the worst recall, and the best recall was the group with a list of 3-digit numbers
• McGeoch & McDonald's experiment supports retroactive interference
• Baddeley & Hitch (1977) found evidence to support retroactive interference
• Baddeley & Hitch (1977) questioned rugby players about games they had played and found that they were able to recall their last match regardless of how long ago it was, but the more regularly they played the less they could recall
• Baddeley & Hitch (1977) had high ecological validity as they used a real-life study
• McGeoch & McDonald (1931) had high internal validity but low external validity