Large-scale recording of unit and field activity with silicon probes

Abstract

Event Abstract Back to Event Large-scale recording of unit and field activity with silicon probes György Buzsáki1* 1 The State University of New Jersey, United States How does the brain orchestrate perceptions, thoughts and actions from the electrical and biochemical dynamics of its neurons? Brain organization exhibits distinct patterns at several levels of scale, ranging from the synapses, to local circuits, and to interacting systems. Addressing these challenging issues requires methods with sufficiently high temporal and spatial resolution of neuronal activity in both local and global networks. Although numerous methods, such as macroscopic and microscopic imaging, molecular biological tools and pharmacological manipulations, are available to study brain activity, in the end all these indirect observations should be converted back into a common currency—the format of neuronal spike trains—to understand the brain’s control of behavior. Specific behaviors emerge from the interaction of neurons and neuronal pools. Studying these processes requires simultaneous monitoring of the activity of large numbers of individual neurons in multiple brain regions. A major goal therefore is to record from statistically representative samples of identified neurons from several local areas while minimally interfering with brain activity. Micro-machined silicon electrode arrays can record from large numbers of neurons and monitor local neural circuits in behaving animals. Synaptic interactions can be identified, which can serve to segregate excitatory and inhibitory neurons. Current methods allow for recoding neurons as far as 100 µm or more form the soma and thick apical dendrites. In such volume of tissue hundreds or thousands of neurons reside. Isolation and identification of multiple neurons from a single recording site is not possible because all aspects of spikes (duration, amplitude, rise time, decay time) can vary dramatically in different states and behaviors. The use of two or more recording sites allows for the triangulation of distances because the amplitude of the recorded spike is a function of the distance between the neuron and the electrode. Often, this task is accomplished with four or eight closely spaced recording sites. Despite the numerous neuron clustering algorithms developed in various laboratories, in current practice only a small percentage of the available population (typically 5-15 neurons per electrode) can be reliably separated. The remaining neurons are either silent or too small in amplitude, thus preventing reliable separation. Ideally, every part of a probe surface placed in the brain should have monitoring sites. Current industrial technology presently uses almost ten times smaller line features than what is possible at academic institutions. Thus, it is not an unrealistic goal to record from nearly all neurons in a small volume of the brain in behaving animals. Hardware and modeling strategies for increasing neuron yield will be discussed. Regularly spaced recording sites also allow for the monitoring of extracellular current flow with high spatial resolution and this mesoscopic signal can be used to determine the operation modes of local networks. Recording from representatively large portion of the network also allows for studying behavior-dependent synaptic modification among members of the network. Conference: Neuroinformatics 2008, Stockholm, Sweden, 7 Sep - 9 Sep, 2008. Presentation Type: Oral Presentation Topic: Workshop Citation: Buzsáki G (2008). Large-scale recording of unit and field activity with silicon probes. Front. Neuroinform. Conference Abstract: Neuroinformatics 2008. doi: 10.3389/conf.neuro.11.2008.01.158 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 28 Jul 2008; Published Online: 28 Jul 2008. * Correspondence: György Buzsáki, The State University of New Jersey, Newark, United States, nemoABS01@frontiersin.org Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers György Buzsáki Google György Buzsáki Google Scholar György Buzsáki PubMed György Buzsáki Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.