The Pattern Glare Test: Further Exploration of Methodological and Demographic Factors

19 Nov

Non-invasive Temporal Interference Stimulation of the Hippocampus Suppresses Epileptic Biomarkers in Patients with Epilepsy: Biophysical Differences between Kilohertz and Amplitude Modulated Stimulation

Introduction: Medication-refractory focal epilepsy creates a significant clinical challenge, with approximately 30% of patients deemed ineligible for surgery due to involvement of eloquent cortical regions within the epileptogenic network. For these patients, electrical neuromodulation represents a promising alternative therapy. We investigated the potential of non-invasive temporal interference (TI) electrical stimulation in reducing epileptic biomarkers in patients with mesiotemporal epilepsy (MTLE) MATERIAL AND METHOD: Thirteen patients implanted with stereoelectroencephalography (sEEG) depth electrodes received TI stimulation with an amplitude modulation (AM) frequency of 130 Hz (Δf), delivered through either low-frequency (1 kHz + 1.13 kHz) or high-frequency (9 kHz + 9.13 kHz) carrier waves, specifically targeting the hippocampus-a common epileptic focus in MTLE. Intracerebral recordings before, during, and after TI stimulation were compared to recordings during sham stimulation at varying high-frequency (HF) carrier frequencies (1, 2, 5, and 9 kHz).

19 Nov

Information-theoretic gradient flows in mouse visual cortex

Introduction: Neural activity can be described in terms of probability distributions that are continuously evolving in time. Characterizing how these distributions are reshaped as they pass between cortical regions is key to understanding how information is organized in the brain.

Methods: We developed a mathematical framework that represents these transformations as information-theoretic gradient flows - dynamical trajectories that follow the steepest ascent of entropy and expectation. The relative strengths of these two functionals provide interpretable measures of how neural probability distributions change as they propagate within neural systems. Following construct validation in silico, we applied the framework to publicly available continuous ΔF/F two-photon calcium recordings from the mouse visual cortex.

Results: The analysis revealed consistent bi-directional transformations between the rostrolateral area and the primary visual cortex across all five mice. These findings demonstrate that the relative contributions of entropy and expectation can be disambiguated and used to describe information flow within cortical networks.