Changes in Error Patterns during N-back Training Indicate Reliance on Subvocal Rehearsal.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Cognitive training literature often shows task-specific improvements or near transfer effects.
• The precise mechanisms driving N-back task performance gains remain underexplored.
• Subvocal rehearsal is a potential strategy influencing N-back performance.

Purpose of the Study:

• To investigate the mechanisms behind N-back task improvement.
• To examine error distributions and strategy reliance during N-back training.
• To assess transfer effects of N-back training to serial order memory tasks.

Main Methods:

• Experiment 1: Analyzed error distributions in 19 non-native English speakers training on an N-back task with phonologically similar words.
• Experiment 2: Assessed transfer to simple span tasks (letter, digit) in participants training on N-back or Operation Span (OSPAN).
• Experiment 3: Examined strategy reliance in 20 participants (native English speakers) training on the N-back task.

Main Results:

• N-back training reduced false alarms and missed targets, but the proportion of phonological errors did not decrease, suggesting increased subvocal rehearsal.
• Participants showed no improvement on simple span tasks after N-back or OSPAN training, indicating a lack of transfer.
• Increased reliance on subvocal rehearsal was observed during N-back training, and self-reported strategy use did not predict performance gains.

Conclusions:

• N-back task improvements are primarily driven by enhanced use of subvocal rehearsal rather than fundamental cognitive skill enhancement.
• N-back training does not appear to transfer to other tasks requiring serial order memory.
• Future research should consider the role of specific strategies like subvocal rehearsal in cognitive training outcomes.