Quantitative EEG Microstates Predict Correct Responses During Visuo-Spatial Working Memory Task

Abstract

Hypothesis: EEG microstate maps during pre-response period of Visuo-Spatial Working Memory (VSWM) Task can predict correct or incorrect response in healthy population and patients with schizophrenia. Methods: After taking informed consent, 30 patients diagnosed with schizophrenia (as per DSM-5 criteria) and 30 controls (both age and gender matched) were recruited. Thereafter, 128 channel EEG was recorded during eyes closed and eyes open states as well as during VSWM task performance. The VSWM task entails matching pairs of identical multicolored abstract pictures hidden in arrays of different cognitive loads after an initial encoding. Following the acquisition; EEG pre-processing, down sampling, average referencing, and Independent Component Analysis were done. Epoch of 100 milliseconds just before each response was taken and grouped into either correct or incorrect trials following which they were subjected to microstate analysis. Statistical analysis was done to compare temporal microstate parameters (Global explained variance, mean duration, time coverage, and segment count density) of each microstate map found between correct and incorrect trials. Data and Results: Microstate maps of pre-response state during correct and incorrect trials were compared in patients with schizophrenia and controls taken together as well as separately. Global explained variance of Microstate Map A (RA-LP, Right Anterior- Left Posterior orientation) was found to be significantly more during pre-response period when the responses were correct as compared to incorrect trials. GEV of Map A emerged out to be the key predictor of correct response in all three groups: overall Correct versus incorrect trials (patients and controls taken together), among patients with schizophrenia, and among controls. Conclusions: Global Explained Variance of EEG microstates Map A is a good predictor of correct response in VSWM task. Department of Physiology, All India Institute of Medical Sciences, New Delhi. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.