eneuro最新文献

{"title":"Auditory encoding of natural speech at subcortical and cortical levels is not indicative of cognitive decline.","authors":"Elena Bolt, Nathalie Giroud","doi":"10.1523/ENEURO.0545-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0545-23.2024","url":null,"abstract":"More and more patients worldwide are diagnosed with dementia, which emphasizes the urgent need for early detection markers. In this study, we built on the auditory hypersensitivity theory of a previous study-which postulated that responses to auditory input in the subcortex as well as cortex are enhanced in cognitive decline-, and examined auditory encoding of natural continuous speech at both neural levels for its indicative potential for cognitive decline. We recruited study participants aged 60 years and older, who were divided into two groups based on the Montreal Cognitive Assessment, one group with low scores (n = 19, participants with signs of cognitive decline), and a control group (n = 25). Participants completed an audiometric assessment and then we recorded their electroencephalography while they listened to an audiobook and click sounds. We derived Temporal Response Functions and evoked potentials from the data and examined response amplitudes for their potential to predict cognitive decline, controlling for age and hearing loss. Contrary to our expectations, no evidence of auditory hypersensitivity was observed in participants with signs of cognitive decline; response amplitudes were comparable in both cognitive groups. Moreover, the combination of response amplitudes showed no predictive value for cognitive decline. These results challenge the proposed hypothesis and emphasize the need for further research to identify reliable auditory markers for the early detection of cognitive decline.Significance statement Research on cognitive decline needs more studies uncovering markers for subtle neural changes in the pre-dementia stage. Neural markers for auditory processing have a potential that has not been widely explored in studies. Here, for the first time, we used natural, continuously spoken language to examine neural processing in two groups of older adults with and without cognitive decline. We quantified how well the brain tracks speech not only at the cortical but also at the subcortical level. In contrast to previous research suggesting that subcortical and cortical auditory responses are enhanced in cognitive decline, we found no group differences. We believe that this study represents an important contribution to the search for markers of cognitive health in old age.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"37 24","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140663156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Loss of Midbrain Dopamine Neurons Does Not Alter GABAergic Inhibition Mediated by Parvalbumin-Expressing Interneurons in Mouse Primary Motor Cortex.","authors":"Suraj Cherian, Gabriel Simms, Liqiang Chen, Hong-Yuan Chu","doi":"10.1523/ENEURO.0010-24.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0010-24.2024","url":null,"abstract":"The primary motor cortex (M1) integrates sensory and cognitive inputs to generate voluntary movement. Its functional impairments have been implicated in the pathophysiology of motor symptoms in Parkinson's disease (PD). Specifically, dopaminergic degeneration and basal ganglia dysfunction entrain M1 neurons into the abnormally synchronized bursting pattern of activity throughout the cortico-basal ganglia-thalamocortical network. However, how degeneration of the midbrain dopaminergic neurons affects the anatomy, microcircuit connectivity, and function of the M1 network remains poorly understood. The present study examined whether and how loss of dopamine (DA) affects the morphology, cellular excitability, and synaptic physiology of layer 5 parvalbumin-expressing (PV+) cells in the M1 of mice of both sexes. Here we reported that loss of midbrain dopaminergic neurons does not alter the number, morphology, and physiology of layer 5 PV+ cells in M1. Moreover, we demonstrated that the number of perisomatic PV+ puncta of M1 pyramidal neurons as well as their functional innervation of cortical pyramidal neurons were not altered following the loss of DA. Together, the present study documents an intact GABAergic inhibitory network formed by PV+ cells following the loss of midbrain dopaminergic neurons.Significance statement The pyramidal neurons in the motor cortex manifests highly synchronized bursting pattern of activity in parkinsonian state, but the underlying circuit mechanisms are poorly understood. One can easily consider PV interneurons-mediated inhibitory network as a potential microcircuitry mechanism. However, whether loss of DA affects cortical PV+ network remains unknown. The present work documented that loss of DA in parkinsonian state does not alter the number, morphology, cellular excitability, and synaptic physiology of PV+ cells in M1. An intact robust PV+ perisomatic inhibition of pyramidal neurons provides a microcircuit substrate for thalamic afferents to entrain cortical neurons to pathological oscillations throughout the cortico-basal ganglia-thalamocortical network in parkinsonian state.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"16 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140663546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increased retinal metabolism induced by flicker in the isolated mouse retina.","authors":"R. Linsenmeier, Andrey V Dmitriev","doi":"10.1523/ENEURO.0509-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0509-23.2024","url":null,"abstract":"Both the retina and brain exhibit neurovascular coupling, increased blood flow during increased neural activity. In the retina increased blood flow can be evoked by flickering light, but the magnitude of the metabolic change that underlies this not known. Local changes in oxygen consumption (QO2) are difficult to measure in vivo when both supply and demand are changing. Here we isolated the C57BL/6J mouse retina and supplied it with oxygen from both sides of the tissue. Microelectrode recordings of PO2 were made in darkness and during 20 sec of high scotopic flickering light at 1 Hz. Flicker led to a PO2 increase in the outer retina and a decrease in the inner retina, indicating that outer retinal QO2 (QOR) decreased and inner retinal QO2 (QIR) increased. A four-layer oxygen diffusion model was fitted to PO2 values obtained in darkness and at the end of flicker to determine the values of QOR and QIR QOR in flicker was 76 ± 14% (mean and SD, n=10) of QOR in darkness. The increase in QIR was smaller, 6.4 ± 5.0%. These metabolic changes are likely smaller than the maximum changes, because with no regeneration of pigment in the isolated retina, we limited the illumination. Further modeling indicated that at high illumination, QIR could increase by up to 45%, which is comparable to the magnitude of flow changes. This suggests that the blood flow increase is at least roughly matched to the increased metabolic demands of activity in the retina.Significance Statement Neural activity increases blood flow in the inner half of the retina as in the brain, but the underlying change in metabolism has been difficult to measure. Here we have measured the increase in metabolism (oxygen consumption, QO2) in mouse retina during flicker. Flicker at high scotopic illumination increased inner retinal QO2 by less than 10% compared to darkness, considerably smaller in magnitude than the well-known light-evoked decrease in QO2 in the outer retina under the same conditions. In the brain, the blood flow increase is larger than is required by the increase in QO2, but in the retina the increase in metabolism and blood flow appear to be more closely matched.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":" 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140685200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulation of neural spiking in motor cortex-cerebellar networks during sleep spindles.","authors":"Pierson Fleischer, Aamir Abbasi, T. Gulati","doi":"10.1523/ENEURO.0150-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0150-23.2024","url":null,"abstract":"Sleep spindles appear to play an important role in learning new motor skills. Motor skill learning engages several regions in the brain with two important areas being the motor cortex (M1) and the cerebellum. However, the neurophysiological processes in these areas during sleep, especially how spindle oscillations affect local and cross-region spiking, are not fully understood. We recorded activity from the M1 and cerebellar cortex in 8 rats during spontaneous activity to investigate how sleep spindles in these regions are related to local spiking as well as cross-region spiking. We found that M1 firing was significantly changed during both M1 and cerebellum spindles and this spiking occurred at a preferred phase of the spindle. On average, M1 and cerebellum neurons showed most spiking at the M1 or cerebellum spindle peaks. These neurons also developed a preferential phase-locking to local or cross-area spindles with the greatest phase-locking value at spindle peaks; however, this preferential phase-locking wasn't significant for cerebellar neurons when compared to cerebellum spindles. Additionally, we found the percentage of task-modulated cells in the M1 and cerebellum that fired with non-uniform spike-phase distribution during M1/ cerebellum spindle peaks were greater in the rats that learned a reach-to-grasp motor task robustly. Finally, we found that spindle-band LFP coherence (for M1 and cerebellum LFPs) showed a positive correlation with success rate in the motor task. These findings support the idea that sleep spindles in both the M1 and cerebellum recruit neurons that participate in the awake task to support motor memory consolidation.Significance Statement Neural processing during sleep spindles is linked to memory consolidation. However, little is known about sleep activity in the cerebellum and whether cerebellum spindles can affect spiking activity in local or distant areas. We report the effect of sleep spindles on neuron activity in the M1 and cerebellum-specifically their firing rate and phase-locking to spindle oscillations. Our results indicate that awake practice neuronal activity is tempered during local M1 and cerebellum spindles, and during cross-region spindles, which may support motor skill learning. We describe spiking dynamics in motor networks spindle oscillations that may aid in the learning of skills. Our results support the sleep reactivation hypothesis and suggest that awake M1 activity may be reactivated during cerebellum spindles.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":" 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140685650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inhibition of Neuron Restrictive Silencing Factor (REST/NRSF) Chromatin Binding Attenuates Epileptogenesis.","authors":"Alicia M Hall, Noriko Kamei, M. Shao, Hyun-Seung Mun, Kevin Chen, Yuncai Chen, T. Baram","doi":"10.1523/ENEURO.0006-24.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0006-24.2024","url":null,"abstract":"The mechanisms by which brain insults lead to subsequent epilepsy remain unclear. Insults including trauma, stroke, infections and long seizures (status epilepticus; SE) increase the nuclear expression and chromatin binding of the neuronal restrictive silencing factor / RE-1 silencing transcription factor (NRSF/REST). REST/NRSF orchestrates major disruption of the expression of key neuronal genes, including ion channels and neurotransmitter receptors, potentially contributing to epileptogenesis. Accordingly, transient interference with REST/NRSF chromatin binding after an epilepsy-provoking SE suppressed spontaneous seizures for the 12- day duration of a prior study. However, whether the onset of epileptogenesis was suppressed or only delayed has remained unresolved. The current experiments determined if transient interference with REST/NRSF chromatin binding prevented epileptogenesis enduringly, or, alternatively, slowed epilepsy onset.Epileptogenesis was elicited in adult male rats via systemic kainic acid-induced SE (KA-SE). We then determined if decoy, NRSF-binding-motif oligodeoxynucleotides (NRSE-ODNs), given twice following KA-SE (a) prevented REST/NRSF binding to chromatin, using chromatin immunoprecipitation; (b) prevented the onset of spontaneous seizures, measured with chronic digital video-EEG.Blocking NRSF function transiently after KA-SE significantly lengthened the latent period to a first spontaneous seizure. Whereas this intervention did not influence the duration and severity of spontaneous seizures, total seizure number and seizure burden were lower in the NRSE- ODN compared with scrambled-ODN cohorts.Transient interference with REST/NRSF function after KA-SE delays and moderately attenuates insult-related hippocampal epilepsy, but does not abolish it. Thus, the anticonvulsant and antiepileptogenic actions of NRSF are but one of the multifactorial mechanisms generating epilepsy in the adult brain.Significance Statement The mechanisms by which brain insults can lead to subsequent epilepsy remain unclear. Insults may influence neuronal functions by enduringly changing their gene expression programs, often via changes in master regulators such as transcription factors (TFs). The TF REST/NRSF is activated by insults, alters gene expression selectively, and thus promotes aberrant neuronal function and connectivity. Previously, blocking REST/NRSF function transiently in developing brain prevented cognitive problems that accompany SE-induced epilepsy. Here, blocking REST/NRSF DNA binding transiently following SE in adult rats delayed and attenuated epileptogenesis, but did not abolish it.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":" 23","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140683265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulatory effects on laminar neural activity induced by near-infrared light stimulation with a continuous waveform to the mouse inferior colliculus in vivo.","authors":"Hiromu Sato, Futoshi Sugimoto, Takahiro Yoshikawa, Takashi Tateno","doi":"10.1523/ENEURO.0521-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0521-23.2024","url":null,"abstract":"Infrared neural stimulation (INS) is a promising area of interest for the clinical application of a neuromodulation method. This is in part because of its low invasiveness, whereby INS modulates the activity of neural tissue mainly through temperature changes. Additionally, INS may provide localized brain stimulation with less tissue damage. The inferior colliculus (IC) is a crucial auditory relay nuclei, and a potential target for clinical application of INS to treat auditory diseases and develop artificial hearing devices. Here, using continuous INS with low to high power density, we demonstrate laminar modulation of neural activity in the mouse IC in the presence and absence of sound. We investigated stimulation parameters of INS to effectively modulate neural activity in a facilitatory or inhibitory manner. A mathematical model of INS-driven brain tissue was first simulated, temperature distributions were numerically estimated, and stimulus parameters were selected from the simulation results. Subsequently, INS was administered to the IC of anesthetized mice, and the modulation effect on neural activity was measured using an electrophysiological approach. We found that the modulatory effect of INS on spontaneous neural activity was bidirectional between facilitatory and inhibitory effects. The modulatory effect on sound-evoked responses produced only an inhibitory effect to all examined stimulus intensities. Thus, this study provides important physiological evidence on the response properties of IC neurons to INS. Overall, INS can be used for the development of new therapies for neurological diseases and functional support devices for auditory central processing.Significance statement Using continuous infrared neural stimulation (INS) of low to high power density, we sought to examine laminar modulation of neural activity in the mouse inferior colliculus (IC) in the presence and absence of sound. We found that the modulatory effect of INS on spontaneous neural activity was bidirectional between facilitatory and inhibitory effects. Additionally, the modulatory effect on sound-evoked responses produced only an inhibitory effect at all examined stimulus intensities. Thus, this study provides important physiological evidence on the response properties of IC neurons to INS. Moreover, INS can be used for the development of new therapies for neurological diseases and functional support devices for auditory central processing.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"12 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140697460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electrophysiological properties of proprioception-related neurons in the intermediate thoracolumbar spinal cord.","authors":"Felipe Espinosa, Iliodora V. Pop, H. Lai","doi":"10.1523/ENEURO.0331-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0331-23.2024","url":null,"abstract":"Proprioception, the sense of limb and body position, is required to produce accurate and precise movements. Proprioceptive sensory neurons transmit muscle length and tension information to the spinal cord. The function of excitatory neurons in the intermediate spinal cord, which receive this proprioceptive information, remains poorly understood. Using genetic labeling strategies and patch clamp techniques in acute spinal cord preparations in mice, we set out to uncover how two sets of spinal neurons, Clarke's column (CC) and Atoh1-lineage neurons, respond to electrical activity and how their inputs are organized. Both sets of neurons are located in close proximity in lamina V-VII of the thoracolumbar spinal cord and have been described to receive proprioceptive signals. We find that a majority of CC neurons have a tonic firing-type and express a distinctive hyperpolarization-activated current (Ih). Atoh1-lineage neurons, which cluster into two spatially distinct populations, are mostly a fading firing-type and display similar electrophysiological properties to each other, possibly due to their common developmental lineage. Finally, we find that CC neurons respond to stimulation of lumbar dorsal roots, consistent with prior knowledge that CC neurons receive hindlimb proprioceptive information. In contrast, using a combination of electrical stimulation, optogenetic stimulation, and transsynaptic rabies virus tracing, we found that Atoh1-lineage neurons receive heterogeneous, predominantly local thoracic inputs that include Parvalbumin-lineage sensory afferents and local interneuron presynaptic inputs. Altogether, we find that CC and Atoh1-lineage neurons have distinct membrane properties and sensory input organization, representing different subcircuit modes of proprioceptive information processing.Significance Statement How excitatory spinal cord neurons in the intermediate spinal cord integrate and relay proprioceptive sensory information is not well understood. Our investigation focuses on two sets of spinal neurons that receive proprioceptive information, but whose electrophysiological response properties have not been previously described. We characterize both their passive and active electrophysiological properties in addition to their input connectivity. We identify unique electrophysiological signatures of each population as well as features of their input organization. We find that a hyperpolarization-activated current distinguishes Clarke's column neurons and that Atoh1-lineage neurons receive predominantly local inputs. These experiments lay the foundation for future endeavors aimed at understanding the mechanisms by which proprioceptive information is integrated and relayed through these neurons.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"36 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140695814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topography and ensemble activity in auditory cortex of a mouse model of Fragile-X-Syndrome.","authors":"Simon L. Wadle, Tamara C Ritter, Tatjana T X Wadle, J. J. Hirtz","doi":"10.1523/ENEURO.0396-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0396-23.2024","url":null,"abstract":"Autism spectrum disorder (ASD) is often associated with social communication impairments and specific sound processing deficits, for example problems in following speech in noisy environments. To investigate underlying neuronal processing defects located in the auditory neocortex (AC), we performed two-photon Ca2+ imaging in FMR1 (Fragile X Messenger Ribonucleoprotein 1) knockout (KO) mice, a model for Fragile-X-Syndrome (FXS), the most common cause of hereditary ASD in humans. For primary AC (A1) and the anterior auditory field (AAF), topographic frequency representation was less ordered compared to control animals. We additionally analyzed ensemble AC activity in response to various sounds and found subfield-specific differences. In A1, ensemble correlations were lower in general, while in secondary AC (A2), correlations were higher in response to complex sounds, yet not to pure tones (PT). Furthermore, sound specificity of ensemble activity was decreased in AAF. Repeating these experiments one week later revealed no major differences regarding representational drift. Nevertheless, we found subfield- and genotype-specific changes in ensemble correlation values between the two times points, hinting at alterations in network stability in FMR1 KO mice. These detailed insights into AC networks activity and topography in FMR1 KO mice add to the understanding of auditory processing defects in FXS.Significance statement Communicative challenges often observed in people with autism spectrum disorder might be due to defects in cortical brain circuits responsible for sound analysis. To investigate these in detail, we used a mouse model of Fragile-X-Syndrome, which often is associated with autism spectrum disorder in humans. We found several alterations compared to control animals, including a less well-ordered topography of frequency analysis in auditory cortex. Furthermore, neuronal population activity patterns in response to various sounds were altered. This was also highly dependent on whether pure tones or complex sounds were presented. These data help to understand the causes of sound processing defects in Fragile-X-Syndrome.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"36 S152","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140694798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct hippocampal oscillation dynamics in trace eye-blink conditioning task for retrieval and consolidation of associations.","authors":"Kayeon Kim, M. Nokia, Satu Palva","doi":"10.1523/ENEURO.0030-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0030-23.2024","url":null,"abstract":"Trace eyeblink conditioning (TEBC) has been widely used to study associative learning in both animals and humans. In this paradigm, conditioned responses (CRs) to conditioned stimuli (CS) serve as a measure for retrieving learned associations between the CS and the unconditioned stimuli (US) within a trial. Memory consolidation i.e. learning over time, can be quantified as an increase in the proportion of CRs across training sessions. However, how hippocampal oscillations differentiate between successful memory retrieval within a session and consolidation across TEBC training sessions remains unknown. To address this question, we recorded local-field potentials (LFPs) from the rat dorsal hippocampus during TEBC and investigated hippocampal oscillation dynamics associated with these two functions. We show that transient broadband responses to the CS were correlated with memory consolidation, as indexed by an increase in CRs across TEBC sessions. In contrast, induced alpha (8-10 Hz) and beta (16-20 Hz) band responses were correlated with the successful retrieval of the CS-US association within a session, as indexed by the difference in trials with and without CR.Significance statement Trace eyeblink conditioning is widely used to study the neural basis of learning. How brain oscillatory signatures for instantaneous retrieval of associations differ from those reflecting long-term memory consolidation is not well understood. We recorded local-field potentials from the rat hippocampus during conditioning to dissociate oscillation dynamics associated with these functions. We show that a transient, early, broadband response is correlated with memory consolidation (increase in conditioned responses across training sessions) whereas long-latency sustained alpha and gamma oscillations are associated with the performance within a given trial in a session.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"82 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140695409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resting state networks of awake adolescent and adult squirrel monkeys using ultra-high field (9.4T) functional magnetic resonance imaging.","authors":"Walid Yassine, Fernando B de Moura, Sarah L. Withey, Lei Cao, Brian D. Kangas, Jack Bergman, S. Kohut","doi":"10.1523/ENEURO.0173-23.2024","DOIUrl":"https://doi.org/10.1523/ENEURO.0173-23.2024","url":null,"abstract":"Resting state networks (RSNs) are increasingly forwarded as candidate biomarkers for neuropsychiatric disorders. Such biomarkers may provide objective measures for evaluating novel therapeutic interventions in nonhuman primates often used in translational neuroimaging research. This study aimed to characterize the RSNs of awake squirrel monkeys and compare the characteristics of those networks in adolescent and adult subjects. Twenty-seven squirrel monkeys (n=12 adolescents [6 male/6 female] ∼2.5 years and n=15 adults [7 male/8 female] ∼9.5 years) were gradually acclimated to awake scanning procedures; whole-brain fMRI images were acquired with a 9.4 Tesla scanner. Group level independent component (ICA) analysis (30 ICs) with dual regression was used to detect and compare RSNs. Twenty ICs corresponding to physiologically meaningful networks representing a range of neural functions, including motor, sensory, reward, and cognitive processes were identified in both adolescent and adult monkeys. The reproducibility of these RSNs was evaluated across several ICA model orders. Adults showed a trend for greater connectivity compared to adolescent subjects in two of the networks of interest: (1) in the right occipital region with the OFC network and (2) in the left temporal cortex, bilateral occipital cortex, and cerebellum with the posterior cingulate network. However, when age was entered into the above model, this trend for significance was lost. These results demonstrate that squirrel monkey RSNs are stable and consistent with RSNs previously identified in humans, rodents, and other nonhuman primate species. These data also identify several networks in adolescence that are conserved and others that may change into adulthood.Significance Statement Functional magnetic resonance imaging procedures have revealed important information about how the brain is modified by experimental manipulations, disease states, and aging throughout the lifespan. Preclinical neuroimaging, especially in nonhuman primates, has become a frequently used means to answer targeted questions related to brain resting-state functional connectivity. The present study characterized resting state networks (RSNs) in adult and adolescent squirrel monkeys; twenty RSNs corresponding to networks representing a range of neural functions were identified. The RSNs identified here can be utilized in future studies examining the effects of experimental manipulations on brain connectivity in squirrel monkeys. These data also may be useful for comparative analysis with other primate species to provide an evolutionary perspective for understanding brain function and organization.","PeriodicalId":506486,"journal":{"name":"eneuro","volume":"313 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140698261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}