In short
The N-back task, first developed by Kirchner in 1958, is a cognitive assessment tool used to measure the performance of working memory and its capacity. This task requires the participant to continuously update their working memory in order to complete the task correctly, by remembering the stimuli presented N trials ago.
Procedure
Generally, participants need to watch for and remember items presented in a sequence. As each new item is shown, they must decide whether it matches the item from N steps earlier in the sequence.
In Gorilla, the participant is required to press the F key on their keyboard if the letter on the screen is the same as the one seen 2 trials previous. If not, participants should press the J key instead.
For example, in a string of letters like K L T L I E I, the participant should press the F key for the fourth letter (L) and the seventh letter (I), as these are the same as the letters presented 2 trials before.
N-back task applications
The N-back task is now utilised in cognitive neuroscience and psychology to test and investigate cognitive load, cognitive decline and the neural mechanisms of our working memory.
Some findings include how variations in performance in the N-back task have been associated with ADHD and schizophrenia. This can help to serve as a diagnostic tool in clinical settings. Also, changes in N-back performance across our lifespan have been used to study cognitive decline with aging.
The theory
One of the theories underpinning this task is Baddeley & Hitch's Working Memory Model. The central executive is a crucial component as it updates and monitors information about stimuli as they appear and helps to decide if it is the same as the stimulus presented N trials earlier. This process relies on information retrieval. The phonological loop is also involved as it helps to refresh verbal information by mentally repeating the items to keep them in working memory. The visuospatial sketchpad allows participants to recognise visual patterns and mentally track the spatial locations of the stimuli. Finally, the episodic buffer is used to maintain a sense of time sequencing. This is essential as participants must refer back to previous trials whilst remembering the presentation sequence.
Can I use N-back tasks in online research?
Yes absolutely! In fact other researchers have used the N-back task as part of a cognitive control training study to investigate response inhibition in children's brains (Ganesan et al., 2024).
How does it work in Gorilla?
You can try out and clone our N-back task. You can also tweak this sample to use your own stimuli.
Have a look: Try an N-back task in Gorilla
Are there any papers Gorilla users have written using the N-back task?
Yes, there are! Have a look at the following article:
References
Chen, Y. N., Mitra, S., & Schlaghecken, F. (2008). Sub-processes of working memory in the N-back task: An investigation using ERPs. Clinical Neurophysiology, 119(7), 1546-1559. https://doi.org/10.1016/j.clinph.2008.03.003
Ganesan, K., Thompson, A., Smid, C. R., Cañigueral, R., Li, Y., Revill, G., ... & Steinbeis, N. (2024). Cognitive control training with domain-general response inhibition does not change children’s brains or behavior. Nature Neuroscience, 1-12. https://doi.org/10.1038/s41593-024-01672-w
Kirchner, W. K. (1958). Age differences in short-term retention of rapidly changing information. Journal of Experimental Psychology, 55(4), 352. https://doi.org/10.1037/h0043688
Miller, K. M., Price, C. C., Okun, M. S., Montijo, H., & Bowers, D. (2009). Is the n-back task a valid neuropsychological measure for assessing working memory?. Archives of Clinical Neuropsychology, 24(7), 711-717. https://doi.org/10.1093/arclin/acp063
Lamichhane, B., Westbrook, A., Cole, M. W., & Braver, T. S. (2020). Exploring brain-behavior relationships in the N-back task. NeuroImage, 212, 116683. https://doi.org/10.1016/j.neuroimage.2020.116683
Meule, A. (2017). Reporting and interpreting working memory performance in n-back tasks. Frontiers in Psychology, 8, 352. https://doi.org/10.3389/fpsyg.2017.00352
This page was written in collaboration with Lizzie Drury
