A5068870868- Neural dynamics and brain function
- Neuroscience and Neuropharmacology Research
- Neuroscience and Neural Engineering
- EEG and Brain-Computer Interfaces
- Epilepsy research and treatment
- Photoreceptor and optogenetics research
- Functional Brain Connectivity Studies
- Memory and Neural Mechanisms
- Neurological disorders and treatments
- Ion channel regulation and function
- Pharmacological Effects and Toxicity Studies
- stochastic dynamics and bifurcation
- Advanced Memory and Neural Computing
- Advanced MRI Techniques and Applications
- Neural and Behavioral Psychology Studies
- Meningioma and schwannoma management
- Fetal and Pediatric Neurological Disorders
- Molecular Communication and Nanonetworks
- Neurofibromatosis and Schwannoma Cases
- Cerebrospinal fluid and hydrocephalus
- Advanced Fluorescence Microscopy Techniques
- Sleep and Wakefulness Research
- Advanced Neuroimaging Techniques and Applications
- Neurobiology of Language and Bilingualism
- Fractal and DNA sequence analysis
Krembil Foundation
2013-2025
University of Toronto
2015-2024
University Health Network
2015-2024
Krembil Research Institute
2016-2024
Toronto Western Hospital
2015-2024
Ontario Brain Institute
2018-2024
Allen Institute for Brain Science
2021-2024
Sungkyunkwan University
2024
Institute for Basic Science
2024
University of Lübeck
2024
Sporadic arteriovenous malformations of the brain, which are morphologically abnormal connections between arteries and veins in brain vasculature, a leading cause hemorrhagic stroke young adults children. The genetic this rare focal disorder is unknown.
Retaining information in working memory is a demanding process that relies on cognitive control to protect memoranda-specific persistent activity from interference
Abstract A broad range of brain pathologies critically relies on the vasculature, and cerebrovascular disease is a leading cause death worldwide. However, cellular molecular architecture human vasculature remains incompletely understood 1 . Here we performed single-cell RNA sequencing analysis 606,380 freshly isolated endothelial cells, perivascular cells other tissue-derived from 117 samples, 68 fetuses adult patients to construct atlas developing fetal, control diseased vasculature. We...
To date, there is little experimental evidence supporting or refuting electrotonic interactions through gap junctions in the generation and/or spread of seizure activity mammalian brain. We have studied junctional mechanisms vitro calcium-free induced model epilepsy using electrophysiological and staining techniques CA1 area hippocampus. Lucifer yellow pyramidal neurons revealed that dye coupling was increased 2.3 times hippocampal slices made hyperexcitable by perfusion with artificial...
Autobiographical memory (AM) provides the opportunity to study interactions among brain areas that support search for a specific episodic (construction), and later experience of mentally reliving it (elaboration).While hippocampus supports both construction elaboration, is unclear how hippocampal-neocortical connectivity differs between these stages, this involves anterior posterior segments hippocampus, as have been considered retrieval general concepts recollection processes,...
Significance During flexible goal-directed behavior, our frontal cortex coordinates goal-relevant information from widely distributed neuronal systems to prioritize the relevant over irrelevant information. This coordination may be realized by entraining multiple with slow activity oscillation phase-align their local fast oscillatory activity. We analyzed this spatially coupling in macaques during actual attentional stimulus selection. identified that successful—but not failed—selection of...
Summary Purpose The clinical relevance of resting state functional connectivity in neurologic disorders, including mesial temporal lobe epilepsy ( mTLE ), remains unclear. This study investigated how the default mode network changes with unilateral damage to one its nodes, hippocampus HC and such can be exploited clinically characterize memory deficits indicate postsurgical change. Methods Functional magnetic resonance imaging (fMRI) scans neuropsychological assessments (Warrington...
Visual exploration in primates depends on saccadic eye movements (SEMs) that cause alternations of neural suppression and enhancement. This modulation extends beyond retinotopic areas, is thought to facilitate perception; yet saccades may also influence brain regions critical for forming memories these exploratory episodes. The hippocampus, example, shows oscillatory activity generally associated with encoding information. Whether or how hippocampal oscillations are influenced by unknown. We...
Abstract In the human neocortex coherent interlaminar theta oscillations are driven by deep cortical layers, suggesting neurons in these layers exhibit distinct electrophysiological properties. To characterize this potential distinctiveness, we use vitro whole-cell recordings from 2 and 3 (L2&3), layer 3c (L3c) 5 (L5) of cortex. Across all observe notable heterogeneity, indicating pyramidal an electrophysiologically diverse population. L5 cells most excitable prominent sag current...
Cortical processing depends on finely tuned excitatory and inhibitory connections in neuronal microcircuits. Reduced inhibition by somatostatin-expressing interneurons is a key component of altered associated with treatment-resistant major depressive disorder (depression), which implicated cognitive deficits rumination, but the link remains to be better established mechanistically humans. Here we test effect reduced somatostatin interneuron-mediated cortical human microcircuits using...
A myriad of pathological changes associated with epilepsy can be recast as decreases in cell and circuit heterogeneity. We thus propose recontextualizing epileptogenesis a process where reduction cellular heterogeneity, part, renders neural circuits less resilient to seizure. By comparing patch clamp recordings from human layer 5 (L5) cortical pyramidal neurons epileptogenic non-epileptogenic tissue, we demonstrate significantly decreased biophysical heterogeneity seizure-generating areas....
Abstract We developed a heart-on-a-chip platform that integrates highly flexible, vertical, 3D micropillar electrodes for electrophysiological recording and elastic microwires the tissue’s contractile force assessment. The high aspect ratio microelectrodes were 3D-printed into device using conductive polymer, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). A pair of quantum dots/thermoplastic elastomer nanocomposite printed to anchor tissue enable continuous flexible...
Humans have the remarkable cognitive capacity to rapidly adapt changing environments. Central this is ability form high-level, abstract representations that take advantage of regularities in world support generalization1. However, little known about how these are encoded populations neurons, they emerge through learning and relate behaviour2,3. Here we characterized representational geometry neurons (single units) recorded hippocampus, amygdala, medial frontal cortex ventral temporal...
Small amplitude depolarizations (fast prepotentials, spikelets) recorded in mammalian neurons are thought to represent either dendritic action potentials or presynaptic attenuated by gap junctions. We have used whole-cell recordings an vitro calcium-free model of epilepsy record spikelets from CA1 the rat hippocampus. It was found that spikelet appearance closely correlated with occurrence dye coupling between pyramidal neurons, indicating both phenomena share a common substrate. Spikelets...
How the brain transitions into a seizure is poorly understood. Recurrent seizure-like events (SLEs) in low-Mg 2+ /high-K + perfusate were measured CA3 region of intact mouse hippocampus. The SLE was divided “preictal phase,” which abruptly turns higher frequency “ictal” phase. Blockade GABA A receptors shortened preictal phase, abolished interictal bursts, and attenuated slow depolarization, with no effect on ictal duration, whereas SLEs blocked by glutamate receptor blockade. In pyramidal...
Despite a wealth of EEG epilepsy data that accumulated for over half century, our ability to understand brain dynamics associated with remains limited. Using from 15 controls and 9 left temporal lobe (LTLE) patients, in this study we characterize how the healthy differ "dynamically balanced" state patients treated anti-epileptic drugs context resting state. We show such differences can be observed band power, synchronization network measures, as well deviations small world (SWN) architecture...
The advancement of implantable medical devices for the treatment neurological disorders demands energy-efficient, low-latency processors responsive, safe, and personalized neuromodulation. A 130-nm CMOS neural interface processor is presented to perform brain-state classification closed-loop control using programmable-waveform electrical stimulation. architecture features an autoencoder network both spatial filtering dimensionality reduction. Dedicated feature extraction blocks are...
Computational models predict that focal damage to the Default Mode Network (DMN) causes widespread decreases and increases of functional DMN connectivity. How such alterations impact functioning in a specific cognitive domain as episodic memory remains relatively unexplored. Here, we show patients with unilateral medial temporal lobe epilepsy (mTLE) structural leads indeed patterns connectivity alterations, specifically decreased between both lobes (MTLs) posterior part increased...