권구상 / 지도교수: 서민아
(융합의과학과 박사과정)
Individual differences in oscillatory brain activity in response to varying attentional demands during a word recall and oculomotor dual task.
Abstract
Every day, we face situations that involve multi-tasking. How our brain utilizes cortical resources during multi-tasking is one of many interesting research topics. In this study, we tested whether a dual-task can be differentiated in the neural and behavioral responses of healthy subjects with varying degree of working memory capacity (WMC). We combined word recall and oculomotor tasks because they incorporate common neural networks including the fronto-parietal (FP) network. Three different types of oculomotor tasks (eye fixation, Fix-EM; predictive and random smooth pursuit eye movement, P-SPEM and R-SPEM) were combined with two memory load levels (low-load: five words, high-load: 10 words) for a word recall task. Each of those dual-task combinations was supposed to create varying cognitive loads on the FP network. We hypothesize that each dual-task requires different cognitive strategies for allocating the brain's limited cortical resources and affects brain oscillation of the FP network. In addition, we hypothesized that groups with different WMC will show differential neural and behavioral responses. We measured oscillatory brain activity with simultaneous MEG and EEG recordings and behavioral performance by word recall. Prominent frontal midline (FM) theta (4-6 Hz) synchronization emerged in the EEG of the high-WMC group experiencing R-SPEM with high-load conditions during the early phase of the word maintenance period. Conversely, significant parietal upper alpha (10-12 Hz) desynchronization was observed in the EEG and MEG of the low-WMC group experiencing P-SPEM under high-load conditions during the same period. Different brain oscillatory patterns seem to depend on each individual's WMC and varying attentional demands from different dual-task combinations. These findings suggest that specific brain oscillations may reflect different strategies for allocating cortical resources during combined word recall and oculomotor dual-tasks.
KEYWORDS:
MEG and EEG; alpha band desynchronization; dual-task; frontal midline theta; oculomotor task; word recall task; working memory capacity
- PMID: 26175681 [PubMed]
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- PMCID: PMC4484223
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(출처_PubMed)
서민아 교수 연구소개 [프로필 보기]
시스템 신경과학 연구실에서는 포괄적 개념의 중개 (translational) 신경과학연구를 수행하고 있다. 물리학, 화학, 공학, 나노과학 등의 융합기술을 이용하여 신개념의 난치성 뇌질환 치료법의 개발을 주된 목표로 삼고 다양한 수준에서의 신경과학연구를 수행하고 있다. 신경줄기세포이식, 직접전기자극, 나노 수준의 실시간 기체 센싱 등을 적극 활용하여 화학, 약물적 접근이 아닌 방법으로 간질, 허혈성 뇌질환 등의 새로운 치료법을 연구하고, 광학이미징, 전기생리학, 다중기체나노센서 등의 신경과학 연구 방법을 이용하여 치료효과와 뇌-신경혈류계의 기능을 모니터링 하고 있다. 시스템 신경과학 연구실에서는 인지신경행동에 관한 연구도 활발하게 진행하여, 주의, 작업기억 등과 행동간의 상관관계를 밝히는 것에 주력하며, 인지기능을 조절할 수 있는 새로운 행동 패러다임의 개발을 연구하고, 이러한 인지와 행동을 조절하는 신경회로망에 대하여 심층적으로 연구하고 있다.
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