Han Hiobeen Ka Eun Lee Choi Ji Hyun (Jee H Choi) 2024-01-12T04:39:51Z 2024-01-12T04:39:51Z 2021-09-29 2019-10-21 - https://pubs.kist.re.kr/handle/201004/78361 Over a decade, coherent theta rhythms (4-12 Hz) within the cerebral cortex have been believed to facilitate information processing by bridging distal brain regions during a task situation. For example, the theta synchrony between prefrontal cortex (PFC) and visual cortex (VC) has been known to be associated with enhanced task performance and attention. Recently, this conceptual framework has been mitigated by a wayward behavior of theta power in VC during sustained attention task: Spyropoulos et al. (2018) observed that the evoked theta in VC decreased as the demands for the visual attention raised in a visual task. Likewise, Stitt et al. (2018) observed that the theta power in high-order VC became lessened by arousal but maintained its synchrony with the PFC in a sustained attention task. These inconsistent behaviors of theta rhythms suggest that theta rhythms in PFC and VC might be differently involved during a task situation. In order to enunciate their different roles, we analyzed EEG signals from mouse PFC and VC during visual Go/No-Go task with respect to short-term task performance. The short-term task performance was assessed by the ratio of correct trials obtained through a moving window over 10 previous trials. We found that PFC and VC theta behaved in an opposite way: PFC (VC) theta was stronger (weaker) in the good-performing epochs compared to the bad-performing epochs. Interestingly, the synchronization between two oscillations increased during the epochs with good performance, despite the suppression of theta in VC. Furthermore, the phase relationship in the fronto-visual phase-locked theta rhythms showed a predominant posterior-to-anterior direction in the order of few milliseconds. Along with the improved synchrony, the delay showed a subtle but systematic decrease, suggesting a boost of information relay from the posterior to the anterior brain region. Our findings not only provide empirical evidence for the distinction between the theta of PFC and VC, but also reveal the overlooked aspect of long-range synchrony between functionally different oscillators in the cerebral cortex. English Society for Neuroscience Functional dissociation of EEG theta rhythms between frontal and visual cortices and their synchronization during sustained attention Conference 1 Neuroscience 2019 Neuroscience 2019 US Chicago, IL 2019-10-19