PT  - JOURNAL ARTICLE
AU  - Mikael Lundqvist
AU  - Jonas Rose
AU  - Melissa Warden
AU  - Tim Buschman
AU  - Pawel Herman
AU  - Earl Miller
TI  - Reduced variability of bursting activity during working memory
AID  - 10.1101/2022.02.18.481088
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2022.02.18.481088
4099  - http://biorxiv.org/content/early/2022/02/18/2022.02.18.481088.short
4100  - http://biorxiv.org/content/early/2022/02/18/2022.02.18.481088.full
AB  - Working memories have long been thought to be maintained by persistent spiking. However, mounting evidence from multiple-electrode recording (and single-trial analyses) shows that the underlying spiking is better characterized by intermittent bursts of activity. A counterargument suggested this intermittent activity is at odds with observations that spike-time variability reduces during task performance. However, this counterargument rests on assumptions, such as randomness in the timing of the bursts, that may not be correct. Thus, we analyzed spiking and LFPs from the prefrontal cortex (PFC) of monkeys to determine if task-related reductions in variability can co-exist with intermittent spiking. We found that it does because both spiking and associated gamma bursts were task-modulated, not random. In fact, the task-related reduction in spike variability could be explained by a related reduction in gamma burst variability. Our results provide further support for the intermittent activity models of working memory as well as novel mechanistic insights into how spike variability is reduced during cognitive tasks.Competing Interest StatementThe authors have declared no competing interest.