Aperiodic spectral slope tracks the effects of brain state on saliency responses in the human auditory cortex.

Alteration of responses to salient stimuli occurs in a wide range of brain disorders and may be rooted in pathophysiological brain state dynamics. Specifically, tonic and phasic modes of activity in the reticular activating system (RAS) influence, and are influenced by, salient stimuli, respectively. The RAS influences the spectral characteristics of activity in the neocortex, shifting the balance between low- and high-frequency fluctuations.

Intraoperative virtual reality for older patients undergoing total knee arthroplasty: study protocol for a randomized clinical trial.

Background: In an aging surgical patient population, preventing complications such as oversedation has taken increasing priority in perioperative care. Intraoperative use of virtual reality (VR) may decrease sedative requirements. We hypothesize that the use of immersive VR during total knee arthroplasty (TKA) will lead to decreased propofol requirements, improved patient-reported satisfaction, and reduced postoperative opioid requirements compared to active and usual care controls.

Aperiodic (1/f) Neural Activity Robustly Tracks Symptom Severity Changes in Treatment-Resistant Depression.

Background: A reliable physiological biomarker for major depressive disorder is essential for developing and optimizing neuromodulatory treatment paradigms. In this study, we investigated a passive electrophysiologic biomarker that tracks changes in depressive symptom severity on the order of minutes to hours.

Methods: We analyzed brief recordings from intracranial electrodes implanted deep in the brain during a clinical trial of deep brain stimulation for treatment-resistant depression in 5 human participants (n = 3, n = 2).

Intracranial Directed Connectivity Links Subregions of the Prefrontal Cortex to Major Depression.

Understanding the neural basis of major depressive disorder (MDD) is vital to guiding neuromodulatory treatments. The available evidence supports the hypothesis that MDD is fundamentally a disease of cortical disinhibition, where breakdowns of inhibitory neural systems lead to diminished emotion regulation and intrusive ruminations. Recent research also points towards network changes in the brain, especially within the prefrontal cortex (PFC), as primary sources of MDD etiology.