Human gamma-band activity (GBA) is widely reported to reflect memory processing. Recent studies suggest that GBA is associated with behavioral performance in memory tasks, but it is not clear whether gamma oscillations are related to individual differences in memory ability. To examine this issue, we recruited participants with low memory ability (mild cognitive impairment, or MCI; n = 16) as well as age-, education-, and sex-matched controls (n = 19) for a study involving a spatial delayed match to sample (DMTS) task. We recorded EEG during task performance and analyzed gamma oscillation changes during the memory maintenance phase of the task. Gamma event-related desynchronization was stronger in the control group than in the MCI group in the mid-frontal area, and mean GBA in this area correlated with clinical memory measures as well as behavioral performance on the DMTS task. These findings suggest that gamma oscillations not only reflect brain activity related to memory processes, but also vary with the memory ability of individuals.
Bibliographical noteFunding Information:
We would like to thank Dr. Jae-Jin Kim, Hae-Jeong Park, and Dong Pyo Jang for their helpful comments. We also thank Soyul Kim and Yul-Mai Song for their assistance with data collection and management. This study was supported by a grant from the Korea Health technology R&D Project, Ministry of Health & Welfare, Republic of Korea ( A092039 ).
All Science Journal Classification (ASJC) codes
- Neuropsychology and Physiological Psychology
- Physiology (medical)