Frequency-specific occipito-prefrontal coupling supports multi-item working memory
Poster No:
869
Submission Type:
Abstract Submission
Authors:
Wenhao Hou1, Sheng He1, Jiedong Zhang1
Institutions:
1Institute of Biophysics, Chinese Academy of Sciences, Beijing, Beijing
First Author:
Co-Author(s):
Introduction:
Working memory is one of the most important cognitive functions of the human brain, and its capacity limits many other cognitive abilities. It is still unclear what is the neural mechanism for the maintenance of multiple items in working memory. Theoretical and experimental evidence suggests that the coupling between theta and gamma band neural activity may support the information maintenance in working memory (Sarnthein et al., 1998; Axmacher et al., 2010; Fell et al., 2011; Lara et al., 2014). Meanwhile, studies of spatial attention have observed that different frequencies of theta band oscillation correspond to different numbers of attended targets (Jiang et al., 2023). Therefore, to investigate the relationship between PAC frequency and the number of items maintained in working memory, MEG was used to estimate the phase-amplitude coupling (PAC) between frontal and occipital cortex in human participants during a visual working memory task.
Methods:
In Exp.1, each trial started with a novel sample object presented to the participants (n = 10). After a 2500 ms blank period, a probe stimulus was presented and participants had to judge whether it was identical to the sample or not. In Exp. 2, two novel sample objects were presented sequentially, and participants (n = 17) had to judge whether the subsequently presented probe object was the same as one of the two samples. MEG signals of the maintenance period were extracted and PAC was estimated between frontal theta-band oscillation and occipital gamma-band power.
Results:
In both experiments, maintaining object information in working memory increased MEG gamma power (30-40 Hz) in occipital cortex and MEG theta power (3-8 Hz) in left frontal cortex. When one object was maintained (Exp.1), the coupling between the phase of frontal theta oscillation and occipital gamma amplitude increased, with the coupling peaking at 8 Hz in the theta band. When two objects were maintained (Exp.2), increased PAC was observed between 4 Hz frontal theta oscillation and occipital gamma amplitude.
·Theta-gamma coupling increased in working memory maintenance period. The modulation peaked at 8 Hz for one item task, and peaked at 4 Hz for two items task.
Conclusions:
Our results reveal the relationship between the frequency of frontal theta band oscillations and working memory load, supporting the idea that the prefrontal cortex communicates with the sensory cortex with theta-band oscillations to maintain information in visual working memory. To support more items in working memory, the frontal cortex may use a slower theta oscillation to couple with neural responses in the sensory cortex, allowing one period of theta phase to modulate more cycles of gamma neural activity.
Learning and Memory:
Working Memory 1
Modeling and Analysis Methods:
EEG/MEG Modeling and Analysis 2
Keywords:
MEG
Other - multi-item, coupling
1|2Indicates the priority used for review
Abstract Information
By submitting your proposal, you grant permission for the Organization for Human Brain Mapping (OHBM) to distribute your work in any format, including video, audio print and electronic text through OHBM OnDemand, social media channels, the OHBM website, or other electronic publications and media.
The Open Science Special Interest Group (OSSIG) is introducing a reproducibility challenge for OHBM 2025. This new initiative aims to enhance the reproducibility of scientific results and foster collaborations between labs. Teams will consist of a “source” party and a “reproducing” party, and will be evaluated on the success of their replication, the openness of the source work, and additional deliverables. Click here for more information. Propose your OHBM abstract(s) as source work for future OHBM meetings by selecting one of the following options:
Please indicate below if your study was a "resting state" or "task-activation” study.
Healthy subjects only or patients (note that patient studies may also involve healthy subjects):
Was this research conducted in the United States?
Were any human subjects research approved by the relevant Institutional Review Board or ethics panel? NOTE: Any human subjects studies without IRB approval will be automatically rejected.
Were any animal research approved by the relevant IACUC or other animal research panel? NOTE: Any animal studies without IACUC approval will be automatically rejected.
Please indicate which methods were used in your research:
Provide references using APA citation style.
Fell, J., et al. (2011). The role of phase synchronization in memory processes. Nature Reviews Neuroscience, 12(2), 105–118.
Jiang, Y., et al. (2023). The adaptive flexibility of rhythmic attentional sampling in attending to multiple targets. Journal of Experimental Psychology. General.
Lara, A. H., et al. (2014). Executive control processes underlying multi-item working memory. Nature Neuroscience, 17(6), 876–883.
Sarnthein, J. et al. (1998). Synchronization between prefrontal and posterior association cortex during human working memory. Proceedings of the National Academy of Sciences, 95(12), 7092–7096.