Motor cortex inputs driving new dendritic spine dynamics
In their Science Advances publication, Sohn et al. from Yoshiyuki Kubota’s group at the National Institute for Physiological Sciences (NIPS) in Japan and Matthew Larkum’s group at Charité in Berlin used NeuroNexus acute, 16-channel probes (A1x16-5mm-100-177-A16) to record M1 neurons during optogenetic inactivation of M2 in C57BL/6J mice. Electrode sites spanned 100µm to 1600µm below the pial surface. Their study characterizes two presynaptic connections involved in pyramidal neuron spine dynamics during motor learning. Transient spines appear and disappear at corticocortical connections, while new and enlarging spines appear at thalamocortical connections.
Read more: https://doi.org/10.1126/sciadv.abm0531
Vagal nerve stimulation may accelerate motor refinement in primary motor cortex via cholinergic signaling
NeuroNexus 32-channel acute and reusable optoelectrodes (A1x32-Edge-10mm-20-177-OA32LP) were used for single-unit recording and opto-tagging of cholinergic neurons in the basal forebrain of healthy mice during vagal nerve stimulation (VNS) following a reach learning task. Spencer Bowles et al. in Cristin Welle’s lab at the University of Colorado School of Medicine describe in Neuron that VNS accelerates motor learning. They propose that VNS effects target behavior-responsive neurons in the primary motor cortex and reinforce correct behavior through acetylcholine signaling. Their results may help refine VNS treatment.
Read more: https://doi.org/10.1016/j.neuron.2022.06.017
Thalamocortical mediation of sensory response timing
Peter Borden and colleagues in Garrett Stanley’s lab at Georgia Tech published in Neuron using NeuroNexus 32-channel acute probes and optoelectrodes (A1x32-5mm-25-177-A32, A1x32-Poly3-5mm-25s-177-OA32LP) to map and record single- and multi-unit activity in mouse somatosensory (whisker) thalamus (VPm) and cortex (S1). Their study tested thalamic mediation of cortical sensory activity, e.g., perception, in awake animals. During optogenetic hyperpolarization of VPm, thalamocortical bursting increased but did not result in increased S1 responses. Rather, S1 synchrony increased, having implications for sensory detection and disrimination.
Read more: https://doi.org/10.1016/j.neuron.2022.06.008
Ripple generation in awake mouse
The dynamics of hippocampal ripple generation was explored through recordings with NeuroNexus acute 32-channel probes (A1x32-15mm-100-177-A32) in awake mice. The 3.1 mm span of recording sites on the linear probe with 100 µm site spacing enabled current source density (CSD) analysis across some of cortex, through dentate gyrus (DG) and CA1, and into thalamus. Results published in eLife from Koichiro Kajikawa et al. and the Thanos Siapas group at Caltech describe hyperpolarization in CA3 together with depolarization in DG and CA1 leading up to ripple-frequency LFPs.
Read more: https://elifesciences.org/articles/69596
Clozapine for neural plasticity after stroke
Jongwook Cho et al and the Hyoung‑Ihl Kim group from Gwangju Institute of Science and Technology (GIST) in Korea published Translational Stroke Research. They used NeuroNexus A1x16-10mm-100-177-A16 probes to measure single-unit activity before and after a single dose of clozapine in a rat model of stroke. Recordings in the sensory-parietal cortex confirmed a significant and persistent increase in firing rate associated with DREADD-based chemogenetic neuromodulation. Results showing increases in markers of neural plasticity support clozapine as a viable option for post-stroke recovery treatment.
Read more: https://doi.org/10.1007/s12975-022-01059-8
Neural correlates of gastric and intestinal signaling
Single-unit recordings were conducted with 16-channel NeuroNexus probes (A2x2-tet-10mm-150-150-121-A16) in the lateral reticular formation (LRN) or the parasubthalamic nucleus (PSTn) of transgenic mice during stomach balloon inflation trials. The results in Cell from Zhang et al. and Ivan E de Araujo’s group at the Icahn School of Medicine at Mount Sinai revealed that LRN neurons detect gastric contractions and PSTn neurons respond to the presence of Glucagon-like peptide-1 (GLP-1). Their new understanding of a gut-brain sensorimotor circuit can help treat gastric disorders.
Read more: https://doi.org/10.1016/j.cell.2022.05.007
Distinguishing nociceptive from tactile input in mouse S1
Pain processing in the mouse somatosensory cortex (S1) was characterized by positioning NeuroNexus 4-shank, 32-channel probes (A4x8-5mm-100-200-177-A32, A4x8-5mm-50-200-177-A32 or Buzsaki32-A32) to distinguish neurons encoding nociceptive versus tactile information. Hironobu Osaki et al. from Tokyo Women’s Medical University performed simultaneous single-unit and multi-unit recordings in E-row barrel fields (BF, tactile) and the adjacent dysgranular region (Dys, nociceptive) using different shanks of their probes. The dense layouts of the probes also enabled distinguishing cortical layers: layer 2/3 processes the two inputs separately, but they converge in layer 5.
Read more: https://doi.org/10.1038/s41467-022-31272-w
Spinal cord stimulation parameters for maximal pain relief
Lee et al. from Nevro Corporation used NeuroNexus A4x4-3mm-50-125-177-A16 probes for acute, single-unit recordings during electrical stimulation in the rat dorsal spinal cord. Probe insertion targeted lamina II-III rostro-caudally along a single mediolateral position. Their findings suggest that simultaneous 10 kHz stimulation applied at a rostral location with 40 Hz stimulation applied at a caudal location has the greatest potential for clinical pain relief through maximal activation of inhibitory interneurons.
Read more: https://doi.org/10.1016/j.neulet.2022.136705
Cortical layers across 40 weeks of chronic recording
NeuroNexus A1x16-3mm-100-703-HZ16 chronic 16-channel probes were implanted into rat somatosensory cortex and used for microstimulation as well as unit recordings to compute neuronal detection thresholds semi-weekly for 16 weeks and regularly for a period of 40 weeks post implant. Spatial resolution was key to differentiating threshold changes correlated with inflammation and scarring in different cortical layers. The results in Frontiers in Neuroscience by Morgan Urdandeta et al. with the Shelley Fried (Massachusetts General Hospital) and Kevin Otto (University of Florida) groups demonstrate that layers 4 and 5 may be the best target for chronic intracortical microstimulation (ICMS) implant longevity.
Read more: https://doi.org/10.3389/fnins.2022.908858
Auditory processing after transient hearing loss in adolescence
The Dan Sanes lab at New York University used NeuroNexus 64-channel Buzsaki64_5x12-H64LP_30mm and A4x16-Poly2-5mm-23s-200-177-H64LP_30mm probes to test auditory processing in adolescent gerbils subject to transient hearing loss. They used custom-mounted NeuroNexus dDrive microdrives to chronically implant the probes to span the tonotopic axis of the left core auditory cortex. Their single-unit and multi-unit recordings demonstrated that perturbation of sensory development during adolescence, separate from the earlier critical period, can cause perceptual deficits attributed to abnormal cortical function.
Read more: https://doi.org/10.1038/s41467-022-30455-9
Late cortical activity in visual perception
In this study of visual stimulus detection and perception, NeuroNexus 32- and 64-channel probes (A1x32-Poly2-10mm-50s-177, A2x16-10mm-100-500-177, A4x8-5mm-100-200-177, A1x64-Poly2-6mm-23s-160) were used for daily insertions into the mouse visual cortex. Recordings included single unit and multiunit activity, plus local field potentials for current source density (CSD) analysis. Additional acute recording techniques and how to distinguish visual cortical layers based on electrophysiology are described in the Nature Communications publication by Lohuis et al. with Cyriel Pennartz and Umberto Olcese at the University of Amsterdam. Their results reveal a neural correlate for late activity in visual perception, namely recurrent, multisensory connections to the visual cortex.
Read more: https://doi.org/10.1038/s41467-022-30600-4
In vivo electrophysiology changes with IL-4Rα deficiency
Hanuscheck et al with Johannes Vogt from the University Medical Center of the Johannes Gutenberg University in Mainz, Germany used NeuroNexus A1x16-3mm-50-177 probes to record single units and LFPs in hippocampus and prefrontal cortex of interleukin-4 (IL-4Rα) deficient mice. Their publication in the Journal of Experimental Medicine reported in vivo electrophysiology showing that theta and gamma power, as well as number of active units and individual unit firing rates are increased when neuronal IL-4Rα is low.
Read more: https://doi.org/10.1084/jem.20211887
Spatially selective cortical activation by intraneural nerve stimulation
A NeuroNexus E32-1000-30-200 ECoG grid was placed on the rabbit visual cortex to record electrically evoked potentials due to intraneural optic nerve stimulation. The study by Dr. Diego Ghezzi’s group at Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland is in the Journal of Neural Engineering and highlights the ability to activate relatively few nerve fibers using their novel stimulating electrode layout. The selectivity resulted in spatially constrained activation in the visual cortex.
Read more: https://doi.org/10.1088/1741-2552/ac6d7e
Motor population coding during failed retention tasks
Single-unit data collected with NeuroNexus A4x8-5mm-100-200-177-A32 probes in the mouse anterior lateral motor cortex (ALM) was openly shared by the Karel Svoboda lab. The present study in eNeuro from Chae et al. at Catholic Kwandong University in South Korea pooled data from two datasets and across delayed-response task trials to create a model of ALM population activity. Their results demonstrate that selectivity is greatest for neurons most strongly correlated with the population activity, but that when selective neurons’ activity is decorelated from the population, even if some neurons encode correctly, memory fails on that trial.
Read more: https://doi.org/10.1523/ENEURO.0490-21.2022
Multimodal recordings of hippocampal seizures
Mulcahey et al. with Hajime Takano at The Children’s Hospital of Philadelphia used the NeuroNexus SmartBox to record for hours at a time both with standard probes and a customized adaptor to connect their graphene arrays. NeuroNexus A4x8-5mm-200-400-177-A32 probes were coated with DiI and inserted into the dorsal hippocampus, CA1 of 8-12 week old C57BL6 mice to record seizures. The silicon probes provided layer-specific resolution for multi-unit activity (MUA) and local field potentials (LFP).
Modulating cortical responses to odor
Olfactory system function was studied using NeuroNexus Buzsaki32-CM32 probes for acute experiments in the mouse piriform cortex. Tal Dalal and Rafi Haddad of Bar-Ilan University recorded single units and LFPs across cortical layers in awake and anesthetized animals, as well as during periods of optical stimulation of the olfactory bulb to enhance gamma oscillations. The authors reported that multi-channel silicon probe recordings gave the same results as single tungsten electrode recordings. Their findings in Cell Reports reveal that granule cell - mitral/tufted cell interactions govern odor responses in cortex.
Read more: https://doi.org/10.1016/j.celrep.2022.110693
Cortical cell type- and layer-specific circuits encoding head direction
Giuseppe Balsamo et al with Andrea Burgalossi at the University of Tuebingen used NeuroNexus acute, two-shank, dual-fiber Buzsaki16-OA16LP optoelectrodes in the mouse presubiculum (PreS) for simultaneous optical perturbation and single-unit recording. Probes were coated with DiI dye before each recording to mark insertion tracks. The researchers then cleaned the probes in 1% Tergazyme for repeated use. Their findings published in Cell Reports shed light on the species-conserved microcircuitry of head direction representation in cortex.
Read more: https://doi.org/10.1016/j.celrep.2022.110684
Behavioral discrimination of optical stimulation enhanced by brain topography
NeuroNexus single-shank 64-channel probes (A1x64-Poly2-6mm-23s-160) were used for multiple oblique penetrations into mouse somatosensory cortex to record single-unit responses while optogenetic stimulation was projected across the recording window. Subsequent findings are published in Lassagne et al in Cell Reports from Luc Estebanez and Valerie Ego-Stengel at Université Paris-Saclay. Their results demonstrate that mice were trained to discriminate the angle of the projected optogenetic bar, but performed worse or were less able to predict success when cortical topography was not continuous (e.g., in the leg area vs barrel cortex).
Read more: https://doi.org/10.1016/j.celrep.2022.110617
Setting standards for anesthetized and sleep-state ephys
Ileana Hanganu-Opatz and Simon Wiegert collaborated to publish a large electrophysiology dataset in Nature Scientific Data. They recorded in mouse CA1 with NeuroNexus A1x16-5mm-50-703-A16 probes, measuring hours of LFP and single-unit data during anesthetized, transitional, and natural sleep states. Analyses of data quality included isolation of the theta band LFP, and measuring single neuron refractory periods.
Read more: https://doi.org/10.1038/s41597-022-01244-2
Cortical representation of sound spectral complexity
This study in Hearing Research took advantage of NeuroNexus 2D probes (A4x8-5mm-50-200-177-A32) to record in a rostral-caudal and dorsal-ventral plane in auditory cortex of the mouse. They were able to distinguish between the primary auditory cortex (A1) and the anterior auditory field (AAF) based on the direction of their tonotopic axes. The linear layout on each shank of the probes enabled laminar analyses to isolate single units in different cortical layers. The results from Tania Rinaldi-Barkat and Magdalena Solyga in the Brain & Sound Lab at Basel University demonstrate that A1 encodes spectral complexity while AAF does not.
Read more: https://doi.org/10.1016/j.heares.2022.108455
Medial septum GABAergic neurons encode reward signals
NeuroNexus optoelectrode polytrodes (A1x16-Poly2-5mm-50s-177-OA16LP) were used for recordings in the mouse medial septum (MS). Nearby groups of electrode sites along the polytrode were sorted as tetrodes. The optoelectrode configuration with fiber termination 200µm above the electrode sites enabled opto-tagging of four different neuron types in transgenic mice. The Nature Communications results from the laboratories of Dr. Li Zhang and Dr. Huizhong Tao at the University of Southern California demonstrate that the somatostatin-positive (SOM) subtype of GABAergic neurons in the medial septum mediate reward association in learning.
Read more: https://doi.org/10.1038/s41467-022-28854-z
CA1 pyramidal cells encode navigation task-relevant information
NeuroNexus high-density Poly3 acute probes (A1x32-Poly3-10mm-25s-177-A32 or A1x32-Poly3-5mm-25s-177-A32) were used to target all 32 recording sites to the CA1 layer of mouse hippocampus for recording individual pyramidal cell spikes. Probes were re-used for multiple sessions in different locations within a craniotomy on successive days. The results from Annabelle Singer’s group at Georgia Tech demonstrate that non-place cells distinguish correct and incorrect behavioral trials when spatial information encoded by place cells is ambiguous relative to the task. They also showed that this encoding does not function normally in a mouse model of Alzheimer’s Disease.
Read more: https://doi.org/10.1073/pnas.2107337119
Bilateral movement coordination in the striatum
Pavel Rueda-Orozco’s lab at UNAM used NeuroNexus Buzsaki64 probes in both acute and chronic experiments to test the role of intratelencephalic bilateral cortico-striatal (bcs-IT) pathways in bilateral forelimb movements. For free behavior, they implanted NeuroNexus Buzsaki64 probes on NeuroNexus dDrives and targeted rat somatosensory cortex and dorsolateral striatum in the same track. Probes were advanced 75-100µm per day and hundreds of units were recorded. Read more about their findings about movement control in Science Advances.
Read more: https://doi.org/10.1126/sciadv.abk2241
fMRI overconnectivity from cortical inactivation
A collaboration between the labs of Stefano Panzeri and Alessandro Gozzi published in Nature Communications. Multiple single-shank NeuroNexus probes (A1x16-5mm-50-703-A16) were inserted simultaneously using the Multi-Probe Manipulator to measure electrophysiological coherence as suggested by resting state fMRI scans. Four-shank probes (A4x8-5mm-200-400-703-A32) were inserted to span midline and target medial prefrontal cortex (PFC) in both hemispheres of the mouse. Their results reveal causes of increased fMRI connectivity.
Read more: https://doi.org/10.1038/s41467-022-28591-3
Hippocampal plasticity induced by tFUS
Niu et al. from Bin He’s lab at Carnegie Mellon University inserted NeuroNexus probes (e.g., A1x16-5mm-50-177-CM16LP and 32-channel designs) at a 50-degree lateral angle to target rat hippocampus. They used the silicon probes to record field EPSPs during transcranial focused ultrasound (tFUS) and revealed that tFUS can induce lasting changes in connectivity.
Read more: https://doi.org/10.1016/j.brs.2022.01.015
Passive responses to echolocation sounds in bat hippocampus
Recent findings published in Hippocampus from the Cynthia Moss lab at Johns Hopkins University reveal that hippocampus neurons in bat respond to echolocation sound duration, but not to features that are typically associated with positioning and navigation. They performed multiple penetration acute recordings using high-density NeuroNexus Buzsaki16 probes to sample ensembles of neurons simultaneously.
Read more: https://doi.org/10.1002/hipo.23407
Auditory temporal processing in aging mice
NeuroNexus 32-channel linear probes (e.g., A1x32-mm-6mm-100-177) were inserted vertically into the inferior colliculus (IC) of aged CBA/J and C57BL/6 mice ranging from 2 or 3 months to 24 months. The 3.1mm coverage of the probes’ electrode sites spanned the full IC, and probes were cleaned and re-used for multiple penetrations. Recordings during auditory tests parse out the effects of central versus peripheral auditory deficits on temporal processing as a model of speech processing. Read the paper by Land and Kral from Hannover Medical School in Neurobiology of Aging.
Respiratory modulation of cortico-hippocampal activity
Nikolas Karalis and Anton Sirota’s publication in Nature Communications uses NeuroNexus standard 16-shank probes (A16x1-2mm-50-177) in prefrontal cortex plus custom designed polytrodes (A1x64-Poly2-6mm-23s-160) in both prefrontal cortex and hippocampus of behaving mice. They recorded single units and measured LFPs both for current source density (CSD) analysis, and to study the oscillations coupled to breathing. Control recordings were done during optogenetically induced ripples. Read more about their results.
Read more: https://doi.org/10.1038/s41467-022-28090-5
Hippocampal rhythms gate tFUS responses
Nguyen et al. and Jacek Dmochowski’s lab at City College of New York recorded local field potentials and multi-unit activity with NeuroNexus A1x32-15mm-100-177-A32 probes. They inserted probes with an angle to target adult rat hippocampal CA1, CA3 and dentate gyrus simultaneously and recorded during transcranial focused ultrasound stimulation (tFUS). Their results published in Brain Stimulation demonstrate that response to tFUS depends on pre-stimulation oscillations and sharp-wave ripples, SWRs.
Read more: https://doi.org/10.1016/j.brs.2022.01.002
Circuit control by all-optical synapses
A fascinating collaboration between Ute Hochgeschwender at Central Michigan University and Christopher Moore at Brown University is out in Nature Communications Biology. They combine simultaneous gamma band LFP recordings with NeuroNexus A1x32-Poly2-5mm-50s-177 probes and imaging for bioluminescence directly adjacent to the silicon shank in barrel cortex of luciferase-expressing mice. These recordings confirm Interluminescence: presynaptic bioluminescence activating postsynaptic opsins.
Read more: https://doi.org/10.1038/s42003-021-02981-7
Hippocampal changes in autism phenotypes
NeuroNexus chronic, 32-channel silicon probes were implanted chronically in behaving adult mice expressing autism-spectrum phenotypes. Paterno et al. from Scott Baraban’s lab at UCSF utilized A4x8-5mm-200-400-703-CM32 probes to record hippocampal LFPs and specifically gamma oscillations. They also used hippocampal sharp-wave ripples (SWR) and dentate spikes to localize the probe. Final probe location was determined with DiI, which was applied before implant. See more of their surgical methods and translational results in Cell Reports.
Read more: https://doi.org/10.1016/j.celrep.2021.109970
Early misconnectivity in a psychiatric risk model
This Journal of Neuroscience paper by Song and Xu et al. from Dr. Ileana Hanganu-Opatz’s lab presents electrophysiology and optogenetics results using NeuroNexus multi-shank, multi-fiber optoelectrodes (A4x4-5mm-100-125-703-OA16LP). The lateral coverage from multiple shanks positioned recording sites in both layers 2/3 and 5/6 of developing mouse (ages P8-10 and P20-24) prefrontal cortex (PFC). They tested excitation and connectivity between PFC and hippocampus (CA1) in a model of mental disorder.
McMahon et al. and the Michel Lemay lab performed simultaneous spinal cord recordings with two NeuroNexus A8x8-5mm-200-200-177, 64-channel probes. They made multiple insertions with the same probe at different spinal segments, and recordings were made during stepping motion, electrical stimulation, as well as control at rest. Probe location marking with DiO was done after recordings were completed. Read more about their discoveries here.
Read more: https://doi.org/10.1152/jn.00202.2021
NeuroNexus optoelectrodes, acute (A1x32-Poly3-10mm-50-177-OA32LP) as well as oDrive-implanted (A1x32-Poly3-10mm-50-177-OH32LP-21mm), are cited in the Cell Press STAR Protocols publication by Tang et al. with Alexandre Charlet’s group. The probes were used for simultaneous electrophysiological recording and opto-tagging of oxytocin neurons. This protocol includes tips for using NeuroNexus oDrives and for spike sorting silicon probe high-density recordings.
Read more: https://doi.org/10.1016/j.xpro.2021.101032
Sales et al. at the University of Bristol inserted NeuroNexus A1x32-Poly3-10mm-25s-177 silicon probes into intact, mechanically stabilized nerve fibers 1-5 times per experiment for 5 experiments with consistent impedance and recording quality. They were able to detect action potential conduction along the multi-channel probe within the nerve.
Kimura and Yoshimura (Science Advances) recorded in layer 5 of visual cortex and analyzed single-unit and LFP data from NeuroNexus 2-shank tetrodes (A2x2-tet-3mm-150-150-121) used across multiple penetrations over several days of experiments. They discovered that single neuron and population responses to low-contrast visual stimuli enabled improved perception after training.
Xu et al. from Dr. Ileana Hanganu-Opatz lab used NeuroNexus acute one-shank optoelectrodes (A1x16-5mm-100-703-OA16LP; A1x16-5mm-50-703-OA16LP) and four-shank optoelectrodes (A4x4-3mm-100-125-703-OA16LP) to target and span recording sites across lateral entorhinal cortex (LEC), CA1 area of the hippocampus (HP), and the prelimbic subdivision of prefrontal cortex (PFC), respectively. Their results uncover novel mechanisms of miswiring in the neonatal brain and highlight the critical role of the LEC for the function of prefrontal-hippocampal circuits.
Read more: https://doi.org/10.1038/s41467-021-27114-w
Dr. Troy Margrie’s group from University College London published their new findings in Neuron. They recorded single units in freely moving mice with chronically implanted NeuroNexus probes (A1x32-Poly2-5mm-50s-177-CM32). They found that angular head velocity (AHV) cells in the retrosplenial cortex (RSP) may be used in path integration by updating the spatial map upon animal movement, and may increase the accuracy of self-motion perception.
Read more: https://doi.org/10.1016/j.neuron.2021.10.031
Dooley et al. from Mark Blumberg’s lab at the University of Iowa examined movement-related activity in ventral lateral (VL) and ventral posterior (VP) thalamic nuclei, as well as primary motor cortex (M1) in postnatal rats, ages P12, P16 and P20. They implanted NeuroNexus probes A1x16-3mm-100-177, A1x16-10mm-100-177, or A2x16-10mm-50-500-177 and recorded single units and twitches. They demonstrate that a cerebellar internal model of movement arises at P20.
Read more: https://doi.org/10.1016/j.cub.2021.10.014
The collaborative team of Ivan Soltesz from Stanford University, Attila Losonczy from Columbia University, Gyorgy Buzsaki from New York University and Z. Josh Huang from Cold Spring Harbor and Duke University recently published their results in Neuron. They implanted NeuroNexus Q-trodes (Q1x4-3mm-100-177-HQ4_21mm) for continuous monitoring of sharp wave-ripples in CA1 and 32-channel optoelectrode (A1x32-Poly3-10mm-50-177-OCM32LP) to measure blue light-evoked responses in CA1 of awake mice. Their results show that axo-axonic cells (AACs) are brain-state dependent and correlated with the onset of locomotion or whisking episodes. The postsynaptic effect of AACs on pyramidal cell spike generation is inhibitory and can remap place fields in the CA1 network.
Read more: https://doi.org/10.1016/j.neuron.2021.09.033
Liu at.al published their results in Nature Communications using NeuroNexus A4x8-5mm microelectrode arrays. Single neuron recordings were captured during optogenetic stimulation with blue, green and red light emitted by trichromatic upcoversion nanoparticles with excitation-specific luminescence. They showed the separation of blue, green, and red color emissions by measuring the spike activity of multiple neuronal populations under selective activation with different wavelengths of near infrared light.
Read more: https://doi.org/10.1038/s41467-021-25993-7
Grosmark et al. from Columbia University published their findings in Nature Neuroscience. They implanted NeuroNexus Qtrodes into the CA1 hippocampus to collect pyramidal cell LFPs contralateral to calcium imaging in mice. They tracked hippocampal place cells over 2 weeks during both online spatial reward learning behavior and offline resting. Their results demonstrate long-lasting, context-specific reactivation of run-related hippocampal neural ensembles as well as the reinstatement of place-related neural sequences. Their findings suggest that post-learning offline memory consolidation plays a complementary and computationally distinct role in learning compared to online encoding.
Read more: https://doi.org/10.1038/s41593-021-00920-7
Sultana et al. used NeuroNexus acute probes to assess whether enzymatic digestion of Perineuronal nets (PNNs) in the prefrontal cortex (PFC) affected neural activity of DISC1 (Disruption in Schizophrenia) mutation mouse model. They found that following chondroitinase treatment, electrophysiological recordings from the PFC exhibited a reduced proportion of spontaneous, high‐frequency firing neurons, and an increased proportion of irregularly firing neurons, with increased spike count and reduced interspike intervals in control animals.
Read more: https://doi.org/10.3390/ijms222011140
Hirokazo Takahashi’s lab used a NeuroNexus probe to simultaneously target the auditory cortex and thalamus of rats. Their published results in Nature Scientific Reports demonstrate that information flow was dynamic depending on the stimulus processing mode and that thalamo-cortical communication was strengthened during stimulus presentation, while disappeared during spontaneous activity.
Read more: https://doi.org/10.1038/s41598-021-98660-y
Craft et al. recorded from the olfactory bulb (OB) of rats using NeuroNexus 32-channel probes (A4x2-tet design) to capture odor evoked spiking activity of putative mitral cells (MCs). They found significant differences in evoked firing rates and spike count covariances. Then, using data-driven models, they provided a framework for how the brain codes odors with different modes of olfaction.
Read more: https://doi.org/10.1371/journal.pcbi.1009169
George Dragoi’s lab at Yale University used chronically implanted Buzsaki64 probes to study populations of simultaneously recorded place cells in rats. Subject exploration of novel environments promoted response generalization, while accumulated experience over several weeks improved discriminability. The results suggest new schemes for how the brain encodes new experiences.
Read more: https://doi.org/10.1016/j.neuron.2021.08.013
Cristin Welle’s lab recently published their new system for integrating chronic, extracellular electrophysiology using NeuroNexus A1x16-3mm-100-177-CM16LP probes with video data to conduct closed-loop stimulation experiments. The linear array was implanted in the mouse motor cortex and captured spike data from all layers during freely moving reach behaviors. These recordings provided neural data to complement behavioral data such that reach-related activity could be extracted.
Read more: https://doi.org/10.1088/1741-2552/ac1ed1
Gao et al. with Alexey Ponomarenko’s group in Berlin, Germany published in Nature Communications! NeuroNexus 32-channel linear probes and 8-shank probes were used to record single spikes and complex spike bursts in hippocampal CA1 neurons of awake behaving mice. Experimental manipulations included KCNQ3 genetic mutation affecting pyramidal cell M-type potassium channels and optogenetic disruption of up-stream circuitry. The paper parses out the factors contributing to coordination of spikes and bursts and how these may impact memory function.
Read more: https://doi.org/10.1038/s41467-021-24805-2
Bilal Haider’s lab at Georgia Tech used NeuroNexus 32-channel probes with linear and poly3 layouts to record neural activity across layers of V1 and LGN, respectively, in head-fixed stationary mice. Their results showed that OFF responses dominated in the central visual field, whereas ON and OFF responses were more balanced in the periphery. These findings were consistent across LFP, spikes, and subthreshold membrane potential in V1, and were aligned with spatial biases in ON and OFF responses in LGN.
Read more: https://doi.org/10.1016/j.cub.2021.06.094
Edelman et al. from Stanford University implanted NeuroNexus 16-channel linear neural electrodes (A1x16-5mm-50-703-A16) into the bilateral primary motor cortex and striatum of mice. They found that functional ultrasound imaging (fUSI) is a more sensitive hemodynamic readout of optogenetically-induced neuronal activity compared to fMRI. Additionally, they found that LFP signals in the bilateral M1 and striatum co-localized better with fUSI activation patterns than those of fMRI. By isolating the arterial and venous components of the vascular response, they showed that fUSI can map large-scale neural circuit activity with vessel-type specificity.
Winkel et al. used NeuroNexus Optoelectrode (A1x16-10 mm-100-177-OA16LP) and SmartBox neural interface processor to capture local field potential data from V1 of mice. They showed that TrkB activation in PV interneurons dynamically regulates the intrinsic properties of the same interneurons by decreasing their intrinsic excitability and switching the PV network into a plastic configuration, which orchestrates adult cortical plasticity states and mediates the effects of antidepressants on neuronal plasticity.
Read more: https://doi.org/10.1038/s41380-021-01211-0
Carl Schoonover et al. published their results in Nature by implanting NeuroNexus A1x32-Poly3-5mm-25s-177 silicon probes into the primary olfactory cortex of mice. They showed that odor-evoked activity in the mouse anterior piriform cortex exhibits rapid and cumulative reorganization over time.
Read more: https://doi.org/10.1038/s41586-021-03628-7
Multi-shank NeuroNexus 32- and 64-channel probes were used to record across and through rodent visual cortex, while single-shank NeuroNexus probes spanned lateral regions to enable tracking of receptive fields. Penetrations were marked with DiI. The results by Eugenio Piasini and Liviu Soltuzu et al. in Davide Zoccolan’s group revealed a hierarchy in processing of dynamic visual stimuli that includes increasingly sustained responses by deeper “ventral stream” visual areas.
Read more: https://doi.org/10.1038/s41467-021-24456-3
Timothy Brown’s team from the University of Manchester used the NeuroNexus SmartBox and 32-, 64-, and 256-channel probes of three different designs (linear, tetrode, polytrode) to record from lateral geniculate nucleus (LGN) in mice with altered M-cone spectral sensitivity (Opn1mwR). Multispectral stimuli were used to address the color processing and neuron properties at higher visual processing stages. Their findings show that cones alone support a diverse capacity for color discrimination that operates for small spatially localized stimuli and diffuse changes in illumination across a range of light levels, providing a robust substrate for mouse color vision. They also demonstrated that cone inputs to opponent neurons derive from the central and upper visual field.
Read more: https://doi.org/10.1016/j.cub.2021.05.024
Multiple NeuroNexus probe designs (A2x32-5mm-25-200-177, A4x8-5mm-100-200-177, Buzsaki32 and Buzsaki64) were used by Andrew King’s lab at Oxford to record from primary sensory cortices, auditory thalamus and inferior colliculus in mice. NeuroNexus probes were also combined with optical stimulation for optogenetics experiments and with DiI dye for acute penetration histology in this study in Nature Communications. The results demonstrate that activity in somatosensory cortex caused by whisker stimulation suppresses sound-evoked activity in primary auditory cortex via the colliculus and thalamus, providing an example of subcortical pathways mediating intra-cortical communication.
Read more: https://doi.org/10.1038/s41467-021-24200-x
Oran et. al used NeuroNexus linear probes (A1x16-10mm-100- 500-177) to evaluate the mechanisms of interhemispheric correlations and their dependence on behavioral state in the barrel cortex of awake mice. They showed that the interhemispheric correlations between the two barrel cortices depend on whisking state, and that the majority of these correlations were decreased during whisking compared to quiet wakefulness. Furthermore, despite general elevated firing rate in the whisking state, the activity of imaged callosal fibers was decreased. These results suggest the causal role of corpus callosum activity in mediating interhemispheric communication, as well as its dependence on the behavioral state of the animal.
Read more: https://doi.org/10.1038/s41467-021-24310-6
Gaillet et al. used the NeuroNexus ECoG array, E32-1000-30-200, to record cortical activity along with a support vector machine classification algorithm to classify cortical responses originating from visual and electrical stimuli. They confirmed an increase in classification accuracy with increased center-to-center separation on patterned visual stimulation. Additionally, their results demonstrated the classification accuracy's dependence on the current amplitude, with higher accuracy at higher amplitudes. They also used a regression model to add a predictive capacity. Using a regression model, they showed that cortical activities elicited by electrical stimulation are meaningfully different, as it highlights features that vary in a linear manner, which can be expected from cortical activity patterns resulting from the stimulation of a gradually shifted portion of the visual field. These results represent a necessary, although not sufficient, condition for an optic nerve prosthesis to deliver vision with non-overlapping phosphene.
Read more: https://doi.org/10.1088/1741-2552/abf523
Results of Krichberger et al. paper using Neuronexus A1x32-5mm-25-177 linear probes along with optogenetics revealed how figure-ground modulation is necessary for perception. Also, they showed that the interactions between lower (V1) and higher areas of the visual cortex shape visual perception, enabling the co-selection of image elements that belong to a single figure and their segregation from the background.
Read more: https://doi.org/10.1126/sciadv.abe1833
Richter et al. explored the possibility of exchanging neural information between the brains of guinea pig and human. They determined characteristic frequency and recorded guinea pig inferior colliculus (ICC) neural response patterns to single spoken words with NeuroNexus A1x16-5mm-100-177 probes. The single-word spike trains were then played through corresponding electrodes of cochlear implants in human subjects. Subject performance on a few word recognition tests was better than chance, confirming the possibility of lexical information transmission from an animal auditory system to the human auditory system.
Read more: https://doi.org/10.1038/s41598-021-90823-1
The Kraskov group used NeuroNexus 32-channel polytrodes (A1x32-Poly3-5mm-25s-177) to record fast and slow motor cortex (M1) pyramidal tract neurons (PTNs) in macaque. Their findings emphasize the importance of pairing electrophysiological and optogenetic approaches in classifying neurons into anatomical and morphological categories.
Read more: https://doi.org/10.1093/cercor/bhab147
Viejo and Peyrache took advantage of NeuroNexus 8-shank polytrodes to sample from multiple sub-nuclei in the anterior thalamus in awake behaving mice. They were able to identify head direction (HD) cells in the AD nucleus and characterize firing rates and burstiness of HD and non-HD cells. Results demonstrated that AD HD cells specifically increase gain and coherence during hippocampal sharp wave ripples.
Read more: https://doi.org/10.1038/s41467-020-15842-4
Congratulations to the Colonnese lab for their new publication in #eNeuro. They used Poly2 probes for dense acute recordings in mouse pup V1 to demonstrate that retinal input does not govern developmental increases in cortical activity. Their recordings were done with the NeuroNexus SmartBox system. Learn more about the updated system here.
Read more: https://doi.org/10.1523/ENEURO.0184-21.2021
Using NeuroNexus linear arrays, dense sampling through the auditory cortex enabled computation of bipolar derivation LFPs for supragranular and infragranular layers. LFPs were also sampled across the posterior auditory field within the ectosylvian sulcus. This study is a great example of using NeuroNexus probes to target hard-to-reach areas.
Read more: https://doi.org/10.3389/fnins.2020.625721
Yu et al. studied the effects of transcranial focused ultrasound modulation by opto-tagging and recording from different neuron types using NeuroNexus opto-electrodes and standard probes. Neural data was recorded using the NeuroNexus SmartBox.
Read more: https://doi.org/10.1038/s41467-021-22743-7
Nelson Totah et al. recently published their paper studying prefrontal cortical control of the locus coeruleus. They use two different NeuroNexus 32-channel probe designs to record single units in anesthetized rats.
Read more: https://doi.org/10.1152/jn.00677.2020
There's a new paper out from Dr Tracy Cui's lab in which NeuroNexus probes were tested under precise stimulation conditions. We are proud to provide devices with consistent electrode site properties to enable studies like this. Congratulations Sally Zheng and co-authors!
Read more: https://doi.org/10.1002/anbr.202000092
It's always exciting when translational studies come out with NeuroNexus as part of the basic science.
Congratulations to the authors!
Read more: https://doi.org/10.1126/scitranslmed.abb4422
Morgan Urdaneta's publication out of Kevin Otto's lab is here! Read it to see how NeuroNexus linear arrays enabled them to define tachaxies across cortical layers.
Read more: https://doi.org/10.1088/1741-2552/abedde
Hot off the presses! We're excited about this new publication featuring a one-of-a-kind custom NeuroNexus silicon microelectrode. This probe has two different shank lengths, as well as a combination of recording and simulation electrode sites.
Read more: https://doi.org/10.3389/fnhum.2021.618626
This collaboration between the Dietmar Schmitz and Gyorgy Buzsaki labs utilized 32-channel and 256-channel multi-shank NeuroNexus probes and optoelectrodes. The geometry of the probes enabled positioning shanks in the mouse hippocampus/dentate gyrus, subiculum and granular retrosplenial cortex simultaneously. Through acute electrophysiology and optogenetic manipulation, this team defined a pathway by which sharp wave ripples communicate from the hippocampus to cortex.
Read more: https://doi.org/10.1038/s41467-020-15787-8
This publication in eNeuro provides highlights valuable data obtained from acute recordings with standard NeuroNexus catalog probes in macaque visual cortices. The researchers covered the skull with acrylic resin, performed a craniotomy through the resin, then inserted silicon probes through a slit in the dura. Re-use of the probes and multiple recordings in the same animals were achieved with this method. Original recordings were published here. The present study’s computational results suggest that saliency of visual stimuli are represented in primary visual cortex.
Read more: https://doi.org/10.1523/ENEURO.0200-20.2020
Neuronexus A2x16-10mm-150-500-177-A32, 2-shank laminar probes were used to record the control frequency tuning profile of the guinea pig inferior colliculus. The animals were then acutely deafened and probe recordings were used to characterize inferior colliculus activity during use of cochlear implants with different stimulation profiles. This study in Hearing Research points to a solution for reducing channel interactions in cochlear implants, with the potential to improve speech detection for cochlear implant users.
Read more: https://doi.org/10.1016/j.heares.2020.108070
Koch et al. from John Wolf’s Lab published their study on functional status of hippocampal neurons after traumatic brain injury (TBI). A NeuroNexus 32-channel probe (A1X32-Poly2-5mm-50s-177-H32) was used for laminar recording in CA1 in a rat TBI model. They reported that hippocampal CA1 single-unit activity post-TBI can maintain a normal firing rate despite significantly reduced, layer-specific loss of input. However, maintaining normal synchronization to the dominant oscillations within the hippocampus is impaired.
Read more: https://doi.org/10.1523/ENEURO.0495-19.2020
Lipinski et al. published their study on adult neuron identity recently! A NeuroNexus 32-channel linear array with 50um site spacing (approx 1.5mm recording span) was used to record simultaneously from the CA1 and dentate gyrus in mutant mice with an inducible genetic mutation to delete two transcriptional co-activators. Across acute multi-channel recordings, drops in activity were observed within 2 weeks of genetic ablation.
Read more: https://doi.org/10.1038/s41467-020-16246-0