Janna Lendner

Host: Eus van Someren
Group leader van Someren group. Email: e.van.someren@nin.knaw.nl

Guest speaker: Janna Lendner, MD PhD
Department of Anesthesiology and Critical Care, University Medical Center Tübingen, Germany & Neurophysiological basis of unconsciousness lab, Yale University, New Haven, Connecticut, USA.

Title: Neural noise or neural code? The significance of aperiodic neural dynamics.

Abstract:

Neural oscillations have long served as the dominant framework for interpreting brain dynamics. However, growing evidence suggests that aperiodic neural activity caries critical information about cognitive function and neural processing. Unlike periodic oscillations, aperiodic activity lacks a well-defined rhythm, instead reflecting the scale-free properties of neural signals. Shifts in aperiodic signal components have been linked to cognitive processes, age-related changes, and neuropsychiatric disorders, yet the neural basis of this activity remains unclear. The fluctuations of aperiodic activity are often attributed to changes in the balance between neuronal excitation and inhibition but direct experimental evidence for this relationship remains scarce.

In this talk, we will examine the significance of aperiodic activity, its potential origins, methodological approaches for quantification, and implications for cognitive neuroscience. We will explore how aperiodic brain activity interacts with oscillatory dynamics to shape neural excitability, network organization, and information processing in the brain. Drawing on electrophysiological data from humans and rodents – including scalp and intracranial electroencephalography, two-photon calcium imaging, and optogenetics – we will highlight the need to move beyond traditional oscillation-centric models to fully capture the complexity of neural dynamics.