A5001931286- Neural dynamics and brain function
- Memory and Neural Mechanisms
- EEG and Brain-Computer Interfaces
- Neuroscience and Neuropharmacology Research
- Functional Brain Connectivity Studies
- Neurological disorders and treatments
- Epilepsy research and treatment
- Neuroscience and Neural Engineering
- Memory Processes and Influences
- Sleep and Wakefulness Research
- Meningioma and schwannoma management
- Vagus Nerve Stimulation Research
- Head and Neck Surgical Oncology
- Cerebrospinal fluid and hydrocephalus
- Pharmacological Effects and Toxicity Studies
- Traumatic Brain Injury Research
- Neurosurgical Procedures and Complications
- Visual perception and processing mechanisms
- Neural and Behavioral Psychology Studies
- Respiratory and Cough-Related Research
- Fetal and Pediatric Neurological Disorders
- Spinal Fractures and Fixation Techniques
- Action Observation and Synchronization
- Traumatic Brain Injury and Neurovascular Disturbances
- Gene Regulatory Network Analysis
The University of Texas Southwestern Medical Center
2016-2025
Neurological Surgery
2016-2025
Southwestern Medical Center
2016-2025
The University of Texas at Austin
2019-2021
Southwestern University
2017-2021
Oxford University Press (United Kingdom)
2018-2020
Nanotherapeutics (United States)
2019
Cleveland Clinic
2014-2019
The Neurological Institute
2019
Hospital of the University of Pennsylvania
2011-2014
Abstract The importance of the hippocampal theta oscillation (4–8 Hz) to memory formation has been well‐established through studies in animals, prompting researchers propose comprehensive theories and learning that rely on oscillations for integrating information hippocampus neocortex. Yet, empirical evidence 4–8 Hz humans is equivocal at best. To clarify this apparent interspecies discrepancy, we recorded intracranial EEG (iEEG) data from 237 electrodes 33 neurosurgical patients as they...
Abstract Memory failures are frustrating and often the result of ineffective encoding. One approach to improving memory outcomes is through direct modulation brain activity with electrical stimulation. Previous efforts, however, have reported inconsistent effects when using open-loop stimulation target hippocampus medial temporal lobes. Here we use a closed-loop system monitor decode neural from recordings in humans. We apply targeted lateral cortex report that this rescues periods poor This...
Phase–amplitude coupling (PAC) has been proposed as a neural mechanism for coordinating information processing across brain regions. Here we sought to characterize PAC in the human hippocampus, and temporal frontal cortices, during formation of new episodic memories. Intracranial recordings taken 56 neurosurgical patients studied recalled lists words revealed significant hippocampal PAC, with slow-theta activity (2.5–5 Hz) modulating gamma band (34–130 Hz). Furthermore, number electrodes...
The idea that synchronous neural activity underlies cognition has driven an extensive body of research in human and animal neuroscience. Yet, insufficient data on intracranial electrical connectivity precluded a direct test this hypothesis whole-brain setting. Through the lens memory encoding retrieval processes, we construct maps fast gamma (30-100 Hz) slow theta (3-8 spectral activity, based from 294 neurosurgical patients fitted with indwelling electrodes. Here report networks...
Abstract Based on rodent models, researchers have theorized that the hippocampus supports episodic memory and navigation via theta oscillation, a ~4–10 Hz rhythm coordinates brain-wide neural activity. However, recordings from humans indicated hippocampal oscillations are lower in frequency less prevalent than rodents, suggesting interspecies differences theta’s function. To characterize human theta, we examine properties of throughout anterior–posterior length as neurosurgical subjects...
Significance Time cells are neurons in the hippocampus and entorhinal cortex that fire at specific moments within a cognitive task or experience. While many prominent theories of memory encoding offer time as source temporal component to memory, they have never been observed human recordings. We identify cell populations medial lobe humans during retrieval. Further, we demonstrate stability signal provided by influences ability temporally order memories
Chronic subdural hematoma (CSDH), a condition much more common in the elderly, presents an increasing challenge as population ages. Treatment strategies for CSDH include bur-hole craniostomy (BHC), twist-drill (TDC), and craniotomy. Decision analysis was used to organize existing data develop recommendations effective treatment.A Medline search identify articles about treatment of CSDH. Direct assessment by health care professionals relative impact complications recurrences generate utility...
Abstract The hippocampus plays a vital role in various aspects of cognition including both memory and spatial navigation. To understand electrophysiologically how the supports these processes, we recorded intracranial electroencephalographic activity from 46 neurosurgical patients as they performed task. We measure signals multiple brain regions, left right hippocampi, use spectral analysis to identify oscillatory patterns related encoding show that but not hippocampus, amplitude...
Direct electrical stimulation of the brain has emerged as a powerful treatment for multiple neurological diseases, and potential technique to enhance human cognition. Despite its application in range disorders, it remains unclear how discrete areas affects memory performance underlying electrophysiological activities. Here, we investigated effect direct four regions known support declarative memory: hippocampus (HP), parahippocampal region (PH) neocortex, prefrontal cortex (PF), lateral...
The medial temporal lobe (MTL) is known to support episodic memory and spatial navigation, raising the possibility that its true function form “cognitive maps” of any kind information. Studies in humans animals idea hippocampal theta rhythm (4 8 Hz) key this mapping function, as it has been repeatedly observed during navigation tasks. If are 2 sides same coin, we hypothesized oscillations might reflect relations between explicitly nonspatial items, such words. We asked 189 neurosurgical...
The subthalamic nucleus (STN), which receives excitatory inputs from the cortex and has direct connections with inhibitory pathways of basal ganglia, is well positioned to efficiently mediate action selection. Here, we use microelectrode recordings captured during deep brain stimulation surgery as participants engage in a decision task examine role human STN We demonstrate that spiking activity increases when level degree conflict. These data implicate an important mediator selection processes.
Functional differences in the anterior and posterior hippocampus during episodic memory processing have not been examined human electrophysiological data. This is spite of strong evidence for such rodent data, including greater place cell specificity dorsal hippocampus, sensitivity to aversive or motivational content memories ventral regions, connectivity analyses identifying preferential hippocampal connections with amygdala, gene expression a dorsal-ventral gradient. We asked if...
Hypoxia-inducible factor 1 (HIF-1) is a master transcriptional regulator in response to hypoxia and its activity crucial for cancer cell mobility. Here we present evidence novel epigenetic mechanism that regulates HIF-1 HIF-1-dependent migration of glioblastoma cells. The lysine methyltransferases G9a GLP directly bound the α subunit (HIF-1α) catalyzed mono- di-methylation HIF-1α at (K) 674 vitro vivo. K674 methylation suppressed expression downstream target genes PTGS1, NDNF, SLC6A3,...
Researchers have used direct electrical brain stimulation to treat a range of neurological and psychiatric disorders. However, for be maximally effective, clinicians researchers should optimize parameters according desired outcomes.The goal our large-scale study was comprehensively evaluate the effects at different locations on neuronal activity across human brain.To examine how kinds affect activity, we compared changes in that resulted from frequencies, amplitudes, with recordings. We...
Gamma frequency activity (30-150 Hz) is induced in cognitive tasks and thought to reflect underlying neural processes. can be recorded directly from the human brain using intracranial electrodes implanted patients undergoing treatment for drug-resistant epilepsy. Previous studies have independently explored narrowband oscillations local field potential broadband power increases. It not clear, however, which processes contribute gamma activity, or their dynamics roles during memory...
Summary Objectives Interictal epileptiform discharges ( IED s) have been linked to memory impairment, but the spatial and temporal dynamics of this relationship remain elusive. In present study, we aim systematically characterize brain areas times at which s affect memory. Methods Eighty epilepsy patients participated in a delayed free recall task while undergoing intracranial electroencephalography EEG ) monitoring. We analyzed locations timing relative behavioral data order measure their...
Direct electrical stimulation of the human brain can elicit sensory and motor perceptions as well recall memories. Stimulating higher order association areas lateral temporal cortex in particular was reported to activate visual auditory memory representations past experiences (Penfield Perot, 1963). We hypothesized that this effect could be used modulate processing. Recent attempts at enhancement have been focused on hippocampus other mesial lobe structures, with a few reports improvement...
The medial temporal lobe (MTL) is widely implicated in supporting episodic memory and navigation, but its precise functional role organizing across time space remains elusive. Here we examine the specific cognitive processes implemented by MTL structures (hippocampus entorhinal cortex) to organize using electrical brain stimulation, leveraging ability establish causal links between regions features of behavior. We studied neurosurgical patients both sexes who performed spatial-navigation...
Neuroimaging experiments implicate the posterior cingulate cortex (PCC) in episodic memory processing, making it a potential target for responsive neuromodulation strategies outside of hippocampal network. However, causal evidence role that PCC plays encoding is lacking. In human female and male participants (N = 17) undergoing seizure mapping, we investigated functional properties using deep brain stimulation (DBS) stereotactic electroencephalography. We used verbal free recall paradigm...
Models of memory formation posit that episodic depends critically on the hippocampus, which binds features an event to its context. For this reason, contrast between study items are later recollected with their associative pair versus those for no association is made fails should reveal electrophysiological patterns in hippocampus selectively involved encoding. Extensive data from studies rodents support a model theta oscillations fulfill role, but results humans have not been as clear....