Oakyoon Cha¹ (); ¹Department of Psychology, Sungshin Women's University

Several studies propose that neural oscillations in the theta and alpha bands serve as mechanisms for sensory gating. According to the communication-through-coherence (CtC) theory (Fries, 2009), effective neural communication relies on aligning the phases of ongoing theta/alpha oscillations across neurons in different brain regions. Consequently, theta- and alpha-band neural oscillations modulate gamma-band neural activities to facilitate or suppress neural communication. The rhythmic theory of attention (Fiebelkorn & Kastner, 2019) posits that theta-band oscillations act as a clock signal for attentional sampling and shifting mechanisms. In this context, the visual system samples information during one phase of the theta band oscillation and shifts attention to a new location in the subsequent phase. To date, no study has investigated whether theta and alpha bands offer advantages over other frequencies in the context of gating mechanisms. The present study explored optimal frequency bands of neural oscillations for sensory gating by examining how oscillations can function as gating mechanisms in a modified one-choice drift-diffusion model (DDM). The modified DDM incorporates CtC theory by using a sine wave to modulate the drift rate, simulating oscillations in the population of signal-sending neurons. Simultaneously, the decision criterion is modulated with a cosine wave, simulating oscillations in the population of signal-receiving neurons. I found that lower-frequency oscillations in the drift rate left stronger traces in the response time distribution of the DDM, while lower-frequency oscillations in the decision criterion exhibited a less pronounced effect. Importantly, phase differences resulted in the most substantial modulation on the strength of oscillatory traces when the oscillation frequency embedded in the drift rate and decision criterion was within theta and alpha bands. In conclusion, the present study underscores that theta- and alpha-band oscillations exhibit optimal characteristics for gating mechanisms within the context of CtC theory.

Acknowledgements: This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (Ministry of Science and ICT) (No. RS-2023-00211668).