Research
I use multimodal cognitive neuroscience methods and biophysical models of electrophysiological signals to study the neural mechanisms that underlie inhibitory control in humans. ​
My research program aims to fill the gap between behavioral-cognitive theories of inhibitory control and its neural mechanisms, lending a multi-level understanding of this type of control that will better facilitate clinical application in neuropsychiatric disorders marked by inhibitory control deficits (e.g., OCD, ADHD, Parkinson's, schizophrenia, etc.). Inhibitory control of ongoing motor actions is most often studied using the Stop-Signal Task, in which participants initiate responses to "Go" cues, but must attempt to cancel those responses following "Stop" cues (Logan and Cowan, 1984). Despite a lack of a button press during successful Stops, the task allows for estimation of how long stopping requires (Verbruggen et al., 2009). However, squaring the predictions and assumptions of behavioral-cognitive models of this task with neural recordings has challenged the field. I am confident that fruitful approaches for constructing such a cross-level understanding include: testing mechanistically-informed frameworks of stopping (e.g., two-stage models; Diesburg and Wessel, 2021), applying cutting-edge analytic techniques to reveal the true nature of neural signals of control (e.g., spectral events; Diesburg, Greenlee, and Wessel, 2021), and interrogating the plausibility of behavioral-cognitive theory with regard to neural correlates (e.g., "Do Stop-Signal EEG signals align with the horse-race model?"; Diesburg et al., 2024).
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My methodological toolbox has included electroencephalography (EEG), local field potentials (LFP) from deep subcortical and surface cortical regions (i.e., stereotactic and ECog arrays), electromyography (EMG), single-pulse and repetitive transcranial magnetic stimulation (TMS), deep brain stimulation (DBS), and magnetic resonance spectroscopy (MRS). I leverage these approaches to perform observational and "causal" experiments in regions involved in fronto-basal ganglia circuits implicated in action-stopping and motor conflict.
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During my postdoctoral training, I have leveraged Human Neocortical Neurosolver - a biophysically-realistic model of the canonical neocortical column under exogenous drive (Neymotin et al., 2020) - to predict thalamocortical dynamics that generate human EEG signals associated with inhibitory control. Ongoing and future research will further integrate this tool within my research pipeline through empirical tests of model-based predictions about mechanisms.
Check out some notable publications and presentations below.
Some of my papers are published under the last name Diesburg.
Notable Publications & Preprints

The Pause-then-Cancel model of human action-stopping: Theoretical considerations and empirical evidence
Darcy A. Diesburg & Jan R. Wessel
In this theory/review paper, Jan Wessel and I discuss how the translation of a two-stage model of stopping proposed by Schmidt and Berke in rodents may stand to resolve several outstanding controversies in the field of human action-stopping.

Darcy A. Diesburg, Jeremy D. W. Greenlee, & Jan R. Wessel
Recording from STN, thalamus, and sensorimotor cortex in awake humans, we investigated the dynamics of subcortico-cortical beta bursts during action stopping. In addition, we present evidence in favor of the theoretical account that STN may net-inhibit the thalamus during action-stopping.

Biophysical Modeling of Frontocentral ERP Generation Links Circuit-Level Mechanisms of Action-Stopping to a Behavioral Race Model
Darcy A. Diesburg, Jan R. Wessel, & Stephanie R. Jones
In this modeling investigation, we demonstrate that the Stop-Signal-locked frontocentral ERP is generated by a sequence of thalamocortical drives, whose timing differs in successful versus failed Stops, in alignment with a race model interpretation of late ERP deflections. We also discuss how early differences in ERP amplitudes may violate race model intepretations of these neural proxy signatures and their mechanisms.

Non‑selective inhibition of the motor system following unexpected and expected infrequent events
Carly Iacullo*, Darcy A. Diesburg*, & Jan R. Wessel
Using single-pulse TMS to produce motor-evoked potentials, we demonstrated that infrequent events produce temporary, involuntary suppression of cortico-spinal excitability.
Presentations
Biophysical dynamics of the Stop-Signal P3 during action-stopping
Poster presentation at the 2022 meeting of the Society for Psychophysiological Research
Beta bursts: Signatures of our brain's braking system
Final round recording for the University of Iowa's Three-Minute Thesis Competition
Cortico-subcortical beta burst dynamics underlying movement cancellation
Symposium presentation at the University of Iowa's Cognitive Control Colloquium Showcase
The role of beta burst dynamics in movement cancellation
Faces of the Future Flash Talk presentation for the 2021 meeting of the Society for Psychophysiological Research
Infrequent but expected stimuli elicit automatic, non-selective inhibition
Poster presentation at the 2020 meeting of the Society for Psychophysiological Research