Psychophysiology, 2019, 56, S116. [Paper presented at the 59^th Annual Meeting of the Society of Psychophysiological Research (SPR) in Washington, DC, September 25-29, 2018.]

A critical examination of the convergent and discriminant validity of resting EEG frontal theta and posterior alpha

Ezra E. Smith¹, Craig E. Tenke^1,2,3†, Patricia J. Deldin⁴, Madhukar H. Trivedi⁵, Myrna M. Weissman^1,2, Randy P. Auerbach², Gerard E. Bruder², Diego A. Pizzagalli^6,7, Jürgen Kayser^1,2,3

¹Division of Translational Epidemiology, New York State Psychiatric Institute, New York, New York, USA; ²Department of Psychiatry, Vagelos College of Physicians & Surgeons, Columbia University, New York, New York, USA; ³Division of Cognitive Neuroscience, New York State Psychiatric Institute, New York, New York, USA; ⁴Department of Psychiatry, University of Michigan, Ann Arbor, Michigan, USA; ⁵Department of Psychiatry, University of Texas, Southwestern Medical Center, Dallas, Texas, USA; ⁶Department of Psychiatry, Harvard Medical School, Boston, Massachusetts, USA; ⁷Center for Depression, Anxiety & Stress Research, McLean Hospital, Belmont, Massachusetts, USA; †Author Deceased

Abstract

We developed auditory analogs of visual Ignore/Suppress tasks to dissect the role of perceptual “bottom-up” and “top-down” attention or inhibitory control processes in WM that may underlie cognitive dysfunction in schizophrenia. ERPs (72 sites) were recorded from 31 healthy adults during encoding, maintenance, and item retrieval in 3 tasks (I: Ignore; S: Suppress; R: Remember) consisting of listening to a series of 4 letters alternately presented to each ear (0.6-s SOA), followed by a 3-s maintenance interval and a probe. Subjects selectively attended to letters presented to one ear and ignored those in the other ear (I), suppressed letters presented to one ear (S), or remembered all letters (R). The critical cue was provided either before (I) or after (S) the encoding series, or with the probe (R). Here we focus on ERPs and event-related oscillations (EROs) over the entire 10-s trial interval after reference-free scalp current source density (CSD) transformation. A broad sustained negative slow wave (NSW) was greater for I than S and R during encoding but greater for S than I and R during maintenance. A time-frequency analysis of these data revealed distinct task-specific modulations of prominent mid-frontal theta (MFT) paralleling the NSW effects. Most importantly, MFT was selectively enhanced for S compared to I and R during maintenance (i.e., not due to task difficulty or source memory requirements). These findings, which were effectively replicated after 1-wk retest, strongly implicate MFT as an electrophysiological correlate of inhibition of information stored in WM.

Key Words: auditory WM; mid-frontal theta; cognitive control

[Supported by NIMH grants MH092221, MH092250 and MH115299].