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Charles L. Wilson

Bio: Charles L. Wilson is an academic researcher from University of California, Los Angeles. The author has contributed to research in topics: Hippocampal formation & Epilepsy. The author has an hindex of 49, co-authored 85 publications receiving 9510 citations.


Papers
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Journal ArticleDOI
14 Nov 1980-Science
TL;DR: The limbic potentials reverse polarity over small distances and correlate with unit discharges recorded by the same electrodes, indicating that they are locally generated.
Abstract: Infrequent, attended, auditory and visual stimuli evoke large potentials in the human limbic system in tasks that usually evoke endogenous potentials at the scalp. The limbic potentials reverse polarity over small distances and correlate with unit discharges recorded by the same electrodes, indicating that they are locally generated.

786 citations

Journal ArticleDOI
TL;DR: Property of oscillations with frequencies >100 Hz were studied in kainic acid (KA)‐treated rats and compared with those recorded in normal and kindled rats as well as in patients with epilepsy to determine differences associated with epilepsy.
Abstract: Summary: Purpose: Properties of oscillations with frequencies >100 Hz were studied in kainic acid (KA)-treated rats and compared with those recorded in normal and kindled rats as well as in patients with epilepsy to determine differences associated with epilepsy. Methods: Prolonged in vivo wideband recordings of electrical activity were made in hippocampus and entorhinal cortex (EC) of (a) normal rats, (b) kindled rats, (c) rats having chronic recurrent spontaneous seizures after intrahippocampal KA injections, and (d) patients with epilepsy undergoing depth electrode evaluation in preparation for surgical treatment. Results: Intermittent oscillatory activity ranging from 100 to 200 Hz in frequency and 50–150 ms in duration was recorded in CA1 and EC of all three animal groups, and in epileptic human hippocampus and EC. This activity had the same characteristics in all groups, resembled previously observed “ripples” described by Buzsaki et al., and appeared to represent field potentials of inhibitory postsynaptic potentials (IPSPs) on principal cells. Unexpectedly, higher frequency intermittent oscillatory activity ranging from 200 to 500 Hz and 10–100 ms in duration was encountered only in KA-treated rats and patients with epilepsy. These oscillations, termed fast ripples (FRs), were found only adjacent to the epileptogenic lesion in hippocampus, EC, and dentate gyrus, and appeared to represent field potential population spikes. Their local origin was indicated by correspondence with the negative phase of burst discharges of putative pyramidal cells. Conclusions: The persistence of normal-appearing ripples in epileptic brain support the view that inhibitory processes are preserved. FRs appear to be field potentials reflecting hypersynchronous bursting of excitatory neurons and provide an opportunity to study the role of this pathophysiologic phenomenon in epilepsy and seizure initiation. Furthermore, if FR activity is unique to brain areas capable of generating spontaneous seizures, its identification could be a powerful functional indicator of the epileptic region in patients evaluated for surgical treatment.

681 citations

Journal ArticleDOI
TL;DR: Two similar types of high‐frequency field oscillations recorded from the entorhinal cortex and hippocampus of patients with mesial temporal lobe epilepsy are described, which are found in the epileptogenic region and may reflect pathological hypersynchronous population spikes of bursting pyramidal cells.
Abstract: Ripples are 100–200 Hz short-duration oscillatory field potentials that have recently been recorded in rat hippocampus and entorhinal cortex. They reflect fast IPSPs on the soma of pyramidal cells, which occur during synchronous afferent excitation of principal cells and interneuron networks. We now describe two similar types of high-frequency field oscillations recorded from the entorhinal cortex and hippocampus of patients with mesial temporal lobe epilepsy. The first type appears be the human equivalent of normal ripples in the rat. The second, which we have termed fast ripples (FR), are in the frequency range of 250–500 Hz. FR are found in the epileptogenic region and may reflect pathological hypersynchronous population spikes of bursting pyramidal cells. Hippocampus 1999;9:137–142. © 1999 Wiley-Liss, Inc.

656 citations

Journal ArticleDOI
TL;DR: The strong association between FR and regions of seizure initiation supports the view that FR reflects pathological hypersynchronous events crucially associated with seizure genesis.
Abstract: High-frequency oscillations (100–200 Hz), termed ripples, have been identified in hippocampal (Hip) and entorhinal cortical (EC) areas of rodents and humans. In contrast, higher-frequency oscillati...

631 citations

Journal ArticleDOI
01 May 1997-Neuron
TL;DR: During encoding and recognition, single neurons in the medial temporal lobe discriminated faces from inanimate objects and constructed a "cognitive map" of stimulus attributes comparable to the map of the spatial environment described in the rodent hippocampus.

490 citations


Cited by
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Journal ArticleDOI
TL;DR: The empirical and theoretical development of the P300 event-related brain potential is reviewed by considering factors that contribute to its amplitude, latency, and general characteristics.

6,283 citations

Journal ArticleDOI
25 Jun 2004-Science
TL;DR: Recent findings indicate that network oscillations bias input selection, temporally link neurons into assemblies, and facilitate synaptic plasticity, mechanisms that cooperatively support temporal representation and long-term consolidation of information.
Abstract: Clocks tick, bridges and skyscrapers vibrate, neuronal networks oscillate. Are neuronal oscillations an inevitable by-product, similar to bridge vibrations, or an essential part of the brain’s design? Mammalian cortical neurons form behavior-dependent oscillating networks of various sizes, which span five orders of magnitude in frequency. These oscillations are phylogenetically preserved, suggesting that they are functionally relevant. Recent findings indicate that network oscillations bias input selection, temporally link neurons into assemblies, and facilitate synaptic plasticity, mechanisms that cooperatively support temporal representation and long-term consolidation of information.

5,512 citations

Journal ArticleDOI
TL;DR: The present updated guidelines review issues of risk and safety of conventional TMS protocols, address the undesired effects and risks of emerging TMS interventions, the applications of TMS in patients with implanted electrodes in the central nervous system, and safety aspects of T MS in neuroimaging environments.

4,447 citations

Journal ArticleDOI
TL;DR: The amplitude of the P300 component is controlled multiplicatively by the subjective probability and task relevance of eliciting events, whereas its latency depends on the duration of stimulus evaluation as mentioned in this paper.
Abstract: To understand the endogenous components of the event-related brain potential (ERP), we must use data about the components' antecedent conditions to form hypotheses about the information-processing function of the underlying brain activity These hypotheses, in turn, generate testable predictions about the consequences of the component We review the application of this approach to the analysis of the P300 component The amplitude of the P300 is controlled multiplicatively by the subjective probability and the task relevance of the eliciting events, whereas its latency depends on the duration of stimulus evaluation These and other factors suggest that the P300 is a manifestation of activity occurring whenever one's model of the environment must be revised Tests of three predictions based on this “context updating” model are reviewed Verleger's critique is based on a misconstrual of the model as well as a partial and misleading reading of the relevant literature

3,451 citations

Journal ArticleDOI
TL;DR: This analysis draws on studies of human memory impairment and animal models of memory impairment, as well as neurophysiological and neuroimaging data, to show that this system is principally concerned with memory and operates with neocortex to establish and maintain long-term memory.
Abstract: The medial temporal lobe includes a system of anatomically related structures that are essential for declarative memory (conscious memory for facts and events). The system consists of the hippocampal region (CA fields, dentate gyrus, and subicular complex) and the adjacent perirhinal, entorhinal, and parahippocampal cortices. Here, we review findings from humans, monkeys, and rodents that illuminate the function of these structures. Our analysis draws on studies of human memory impairment and animal models of memory impairment, as well as neurophysiological and neuroimaging data, to show that this system (a) is principally concerned with memory, (b) operates with neocortex to establish and maintain long-term memory, and (c) ultimately, through a process of consolidation, becomes independent of long-term memory, though questions remain about the role of perirhinal and parahippocampal cortices in this process and about spatial memory in rodents. Data from neurophysiology, neuroimaging, and neuroanatomy point to a division of labor within the medial temporal lobe. However, the available data do not support simple dichotomies between the functions of the hippocampus and the adjacent medial temporal cortex, such as associative versus nonassociative memory, episodic versus semantic memory, and recollection versus familiarity.

2,742 citations