Topic: local field potential

A core aspect of clinical epileptology revolves around relating epileptic field potentials to underlying neural sources (e.g. an “epileptogenic focus”). Yet still, how neural population activity relates to epileptic field potentials and ultimately clinical phenomenology, remains far from being understood. After a brief overview on this topic, this seminar will focus on unpublished work, with an emphasis on seizure-related focal spreading depression. The presented results will include hippocampal and neocortical chronic in vivo two-photon population imaging and local field potential recordings

Different prefrontal areas contribute in distinctly different ways to rule-guided behaviour in the context of a Wisconsin Card Sorting Test (WCST) analog for macaques. For example, causal evidence from circumscribed lesions in NHPs reveals that dorsolateral prefrontal cortex (dlPFC) is necessary to maintain a reinforced abstract rule in working memory, orbitofrontal cortex (OFC) is needed to rapidly update representations of rule value, and the anterior cingulate cortex (ACC) plays a key role in cognitive control and integrating information for correct and incorrect trials over recent outcomes

Objective and quantitative assessment of the level of consciousness is a medical demand in clinics and a theoretical challenge to be addressed. Although a growing body of literature suggests different measures to distinguish the levels of consciousness, a systematic comparison of different measures is lacking. Such a systematic comparison, however, is necessary since it assures us of the best solutions to the problem in terms of prediction accuracy and explanatory power but also simplicity and applicability. In this study, we propose taking a massive comparative approach to assess the level of

This talk will focus on different aspects of the Local Field Potential (LFP) signal. Classically, LFP fluctuations are related to changes in the functional state of the cortex. Yet, the mechanisms linking LFP changes with the state of the cortex are not well understood. The presentation will start with a brief explanation of the main oscillatory components of the LFP signal, how these different oscillatory components are generated at cortical microcircuits, and how their dynamics can be studied across multiple areas. Thereafter, a case study of a patient with akinetic mutism will be presented,

Although substance use disorders (SUDs) occur commonly in patients with schizophrenia and significantly worsen their clinical course, the neurobiological basis of SUDs in schizophrenia is not well understood. Therefore, there is a critical need to understand the mechanisms underlying SUDs in schizophrenia in order to identify potential targets for therapeutic intervention. Since drug use usually begins in adolescence, it is also important to understand the long-term effects of adolescent drug exposure on schizophrenia- and reward- related behaviors and circuitry. This talk will combine pharmac

With advances in high-density epicortical electrophysiological recordings (i.e., ECoGs), it became possible to investigate precise spatio-temporal evolution of neural dynamics behind various cognitive functions. This improved resolution allowed for investigation of until now largely disregarded spatial features of neuronal oscillations and challenged the conventional view of global zero-lag synchrony as a basis of neuronal communication. More specifically, it revealed structured phase-offsets in superficial cortical singals corresponding to wave-like dynamics. Further investigation of single-c

Auditory decoding of temporal features is a complex process in which vocalizations such as birdsongs are segmented into distinct auditory units, a crucial step in transforming sound into meaning. The songbird auditory system offers a valuable model for studying the neural representation of complex sounds. The hierarchical structure of the Zebra Finches' song makes it ideal for in-depth analysis of auditory decoding. We use stacked Bidirectional Long Short-Term Memory (BiLSTM) deep neural networks to decode the amplitude envelope and the time-locked envelope features of zebra finch songs. To a

Neural mass models (NMM) seek to unveil the fundamental principles governing macroscopic neural activity, drawing insights from the brain's intricate and multi-scale structure. The advent of an exact mean-field theory for networks of quadratic integrate-and-fire (QIF) neurons represents a significant leap forward in our comprehension of the link between microscale neural mechanisms and mesoscopic brain activity [1]. This model establishes a robust coupling between two biophysically relevant macroscopic quantities: the firing rate and the mean membrane potential, which collectively drive the ev

The primary visual cortex is thought to encode low-level features (orientation/direction, contrast, brightness, etc.), while also enabling adaptation and gain control. However, the kinds of computations it is capable of performing, as an isolated circuit, are not clear.Here, we describe a sensory surprise signal in the local field potential (LFP) in the primary visual cortex (V1) of the anesthetized mouse in response to contrast rate change – a complex, time dependent stimulus parameter. We investigate the population activity responsible for this surprise signal and identify neuronal subgroups