RESUMEN
In interval reproduction tasks, animals must remember the event starting the interval and anticipate the time of the planned response to terminate the interval. The interval reproduction task thus allows for studying both memory for the past and anticipation of the future. We analyzed previously published recordings from the rodent medial prefrontal cortex [J. Henke et al., eLife10, e71612 (2021)] during an interval reproduction task and identified two cell groups by modeling their temporal receptive fields using hierarchical Bayesian models. The firing in the "past cells" group peaked at the start of the interval and relaxed exponentially back to baseline. The firing in the "future cells" group increased exponentially and peaked right before the planned action at the end of the interval. Contrary to the previous assumption that timing information in the brain has one or two time scales for a given interval, we found strong evidence for a continuous distribution of the exponential rate constants for both past and future cell populations. The real Laplace transformation of time predicts exponential firing with a continuous distribution of rate constants across the population. Therefore, the firing pattern of the past cells can be identified with the Laplace transform of time since the past event while the firing pattern of the future cells can be identified with the Laplace transform of time until the planned future event.
Asunto(s)
Neuronas , Corteza Prefrontal , Corteza Prefrontal/fisiología , Corteza Prefrontal/citología , Animales , Ratas , Neuronas/fisiología , Teorema de Bayes , Masculino , Modelos Neurológicos , Memoria/fisiología , Percepción del Tiempo/fisiología , Potenciales de Acción/fisiologíaRESUMEN
This study investigated whether the electric field magnitude (E-field) delivered to the left dorsolateral prefrontal cortex (L-DLPFC) changes resting-state brain activity and the L-DLPFC resting-state functional connectivity (rsFC), given the variability in tDCS response and lack of understanding of how rsFC changes. Twenty-one healthy participants received either 2 mA anodal or sham tDCS targeting the L-DLPFC for 10 min. Brain imaging was conducted before and after stimulation. The fractional amplitude of low-frequency fluctuation (fALFF), reflecting resting brain activity, and the L-DLPFC rsFC were analyzed to investigate the main effect of tDCS, main effect of time, and interaction effects. The E-field was estimated by modeling tDCS-induced individual electric fields and correlated with fALFF and L-DLPFC rsFC. Anodal tDCS increased fALFF in the left rostral middle frontal area and decreased fALFF in the midline frontal area (FWE p < 0.050), whereas sham induced no changes. Overall rsFC decreased after sham (positive and negative connectivity, p = 0.001 and 0.020, respectively), with modest and nonsignificant changes after anodal tDCS (p = 0.063 and 0.069, respectively). No significant differences in local rsFC were observed among the conditions. Correlations were observed between the E-field and rsFC changes in the L-DLPFC (r = 0.385, p = 0.115), left inferior parietal area (r = 0.495, p = 0.037), and right lateral visual area (r = 0.683, p = 0.002). Single-session tDCS induced resting brain activity changes and may help maintain overall rsFC. The E-field in the L-DLPFC is associated with rsFC changes in both proximal and distally connected brain regions to the L-DLPFC.
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Estudios Cruzados , Corteza Prefontal Dorsolateral , Imagen por Resonancia Magnética , Estimulación Transcraneal de Corriente Directa , Humanos , Estimulación Transcraneal de Corriente Directa/métodos , Masculino , Femenino , Adulto , Adulto Joven , Corteza Prefontal Dorsolateral/fisiología , Vías Nerviosas/fisiología , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Mapeo EncefálicoRESUMEN
The dorsolateral prefrontal cortex (dlPFC) is reliably engaged in working memory (WM) and comprises different cytoarchitectonic layers, yet their functional role in human WM is unclear. Here, participants completed a delayed-match-to-sample task while undergoing functional magnetic resonance imaging (fMRI) at ultra-high resolution. We examine layer-specific activity to manipulations in WM load and motor response. Superficial layers exhibit a preferential response to WM load during the delay and retrieval periods of a WM task, indicating a lamina-specific activation of the frontoparietal network. Multivariate patterns encoding WM load in the superficial layer dynamically change across the three periods of the task. Last, superficial and deep layers are non-differentially involved in the motor response, challenging earlier findings of a preferential deep layer activation. Taken together, our results provide new insights into the functional laminar circuitry of the dlPFC during WM and support a dynamic account of dlPFC coding.
Asunto(s)
Imagen por Resonancia Magnética , Memoria a Corto Plazo , Corteza Prefrontal , Humanos , Memoria a Corto Plazo/fisiología , Masculino , Femenino , Adulto , Adulto Joven , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Corteza Prefontal Dorsolateral/fisiología , Corteza Prefontal Dorsolateral/diagnóstico por imagen , Mapeo Encefálico/métodosRESUMEN
The reinforcing nature of social interactions is necessary for the maintenance of appropriate social behavior. However, the neural substrates underlying social reward processing and how they might differ based on the sex and internal state of the animal remains unknown. It is also unclear whether these neural substrates are shared with those involved in nonsocial rewarding processing. We developed a fully automated, two choice (social-sucrose) operant assay in which mice choose between social and nonsocial rewards to directly compare the reward-related behaviors associated with two competing stimuli. We performed cellular resolution calcium imaging of medial prefrontal cortex (mPFC) neurons in male and female mice across varying states of water restriction and social isolation. We found that mPFC neurons maintain largely non-overlapping, flexible representations of social and nonsocial reward that vary with internal state in a sex-dependent manner. Additionally, optogenetic manipulation of mPFC activity during the reward period of the assay disrupted reward-seeking behavior across male and female mice. Thus, using a two choice operant assay, we have identified sex-dependent, non-overlapping neural representations of social and nonsocial reward in the mPFC that vary with internal state and that are essential for appropriate reward-seeking behavior.
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Neuronas , Optogenética , Corteza Prefrontal , Recompensa , Conducta Social , Animales , Corteza Prefrontal/fisiología , Femenino , Masculino , Neuronas/fisiología , Ratones , Ratones Endogámicos C57BL , Caracteres Sexuales , Conducta Animal/fisiología , Condicionamiento Operante/fisiología , Conducta de Elección/fisiología , Aislamiento Social/psicologíaRESUMEN
Task-related studies have consistently reported that listening to speech sounds activate the temporal and prefrontal regions of the brain. However, it is not well understood how functional organization of auditory and language networks differ when processing speech sounds from its resting state form. The knowledge of language network organization in typically developing infants could serve as an important biomarker to understand network-level disruptions expected in infants with hearing impairment. We hypothesized that topological differences of language networks can be characterized using functional connectivity measures in two experimental conditions (1) complete silence (resting) and (2) in response to repetitive continuous speech sounds (steady). Thirty normal-hearing infants (14 males and 16 females, age: 7.8 ± 4.8 months) were recruited in this study. Brain activity was recorded from bilateral temporal and prefrontal regions associated with speech and language processing for two experimental conditions: resting and steady states. Topological differences of functional language networks were characterized using graph theoretical analysis. The normalized global efficiency and clustering coefficient were used as measures of functional integration and segregation, respectively. We found that overall, language networks of infants demonstrate the economic small-world organization in both resting and steady states. Moreover, language networks exhibited significantly higher functional integration and significantly lower functional segregation in resting state compared to steady state. A secondary analysis that investigated developmental effects of infants aged 6-months or below and above 6-months revealed that such topological differences in functional integration and segregation across resting and steady states can be reliably detected after the first 6-months of life. The higher functional integration observed in resting state suggests that language networks of infants facilitate more efficient parallel information processing across distributed language regions in the absence of speech stimuli. Moreover, higher functional segregation in steady state indicates that the speech information processing occurs within densely interconnected specialized regions in the language network.
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Conectoma , Red Nerviosa , Espectroscopía Infrarroja Corta , Percepción del Habla , Humanos , Femenino , Masculino , Lactante , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiología , Percepción del Habla/fisiología , Conectoma/métodos , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , LenguajeRESUMEN
The regulation of emotions is a crucial facet of well-being and social adaptability, with explicit strategies receiving primary attention in prior research. Recent studies, however, emphasize the role of implicit emotion regulation, particularly implicating the ventromedial prefrontal cortex (VMPFC) in association with its implementation. This study delves into the nuanced role of the VMPFC through focality-optimized multichannel transcranial direct current stimulation (tDCS), shedding light on its causal involvement in implicit reappraisal. The primary goal was to evaluate the effectiveness of VMFPC-targeted tDCS and elucidate its role in individuals with high trait anxiety. Participants engaged in implicit and explicit emotion regulation tasks during multichannel tDCS targeting the VMPFC. The outcome measures encompassed negative emotion ratings, pupillary diameter, and saccade count, providing a comprehensive evaluation of emotion regulation efficiency. The intervention exhibited a notable impact, resulting in significant reductions in negative emotion ratings and pupillary reactions during implicit reappraisal, highlighting the indispensable role of the VMPFC in modulating emotional responses. Notably, these effects demonstrated sustained efficacy up to 1 day postintervention. This study underscores the potency of VMPFC-targeted multichannel tDCS in augmenting implicit emotion regulation. This not only contributes insights into the neural mechanisms of emotion regulation but also suggests innovative therapeutic avenues for anxiety disorders. The findings present a promising trajectory for future mood disorder interventions, bridging the gap between implicit emotion regulation and neural stimulation techniques.
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Regulación Emocional , Corteza Prefrontal , Estimulación Transcraneal de Corriente Directa , Humanos , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Regulación Emocional/fisiología , Masculino , Femenino , Adulto , Adulto Joven , Ansiedad/fisiopatología , Ansiedad/terapia , Movimientos Sacádicos/fisiología , Emociones/fisiologíaRESUMEN
While it is widely acknowledged that exercise has positive effects on cognitive function, the specific impacts of different types of exercises, particularly open and closed skill exercises, on cognitive impairment continue to be a debated topic. In this study, we used fNIRS and cognitive psychology tasks to investigate the effects of different types of exercises on cognitive function and brain activity in young adults. We conducted an observational study to assess the cognitive function of participants who had engaged in these exercises for a long period. Additionally, we examined the effects of open skill exercise (badminton) and closed skill exercise (calisthenics) on localized blood flow in the prefrontal lobe of the brain using an experimental research method. Specifically, during the Stroop task, the badminton group exhibited significantly higher â³HbO2 in channel 18, corresponding to the dorsolateral prefrontal cortex, compared to the calisthenics group (F = 4.485, P < 0.05, η2 = 0.074). In the 2-back task, the calisthenics group showed significantly higher â³HbO2 in channel 17, corresponding to the frontopolar area, dorsolateral prefrontal cortex and inferior prefrontal gyrus, than the badminton group (F = 8.842, P < 0.01, η2 = 0.136). Our findings reveal that open skill exercises are more effective in enhancing cognitive inhibition, thereby increasing attention capacity, self-regulation, and flexibility in response to environmental changes. Conversely, closed skill exercises demonstrate greater efficacy in improving working memory within cognitive functions, showcasing an enhanced capacity for information processing and storage. These data indicate that while both open and closed skill exercises are beneficial for cognitive function, they exhibit significant distinctions in some aspects.
Asunto(s)
Cognición , Ejercicio Físico , Espectroscopía Infrarroja Corta , Humanos , Cognición/fisiología , Masculino , Adulto Joven , Espectroscopía Infrarroja Corta/métodos , Femenino , Ejercicio Físico/fisiología , Adulto , Corteza Prefrontal/fisiologíaRESUMEN
The ability to switch between rules associating stimuli and responses depend on a circuit including the dorsomedial prefrontal cortex (dmPFC) and the subthalamic nucleus (STN). However, the precise neural implementations of switching remain unclear. To address this issue, we recorded local field potentials from the STN and from the dmPFC of neuropsychiatric patients during behavioral switching. Drift-diffusion modeling revealed that switching is associated with a shift in the starting point of evidence accumulation. Theta activity increases in dmPFC and STN during successful switch trials, while temporally delayed and excessive levels of theta lead to premature switch errors. This seemingly opposing impact of increased theta in successful and unsuccessful switching is explained by a negative correlation between theta activity and the starting point. Together, these results shed a new light on the neural mechanisms underlying the rapid reconfiguration of stimulus-response associations, revealing a Goldilocks' effect of theta activity on switching behavior.
Asunto(s)
Corteza Prefrontal , Núcleo Subtalámico , Ritmo Teta , Humanos , Corteza Prefrontal/fisiología , Ritmo Teta/fisiología , Masculino , Femenino , Adulto , Núcleo Subtalámico/fisiología , Persona de Mediana Edad , Estimulación Encefálica ProfundaRESUMEN
Cognitive flexibility enables individuals to alter their behavior in response to changing environmental demands, facilitating optimal behavior in a dynamic world. The inability to do this, called behavioral inflexibility, is a pervasive behavioral phenotype in alcohol use disorder (AUD), driven by disruptions in cognitive flexibility. Research has repeatedly shown that behavioral inflexibility not only results from alcohol exposure across species but can itself be predictive of future drinking. Like many high-level executive functions, flexible behavior requires healthy functioning of the prefrontal cortex (PFC). The scope of this review addresses two primary themes: first, we outline tasks that have been used to investigate flexibility in the context of AUD or AUD models. We characterize these based on the task features and underlying cognitive processes that differentiate them from one another. We highlight the neural basis of flexibility measures, focusing on the PFC, and how acute or chronic alcohol in humans and non-human animal models impacts flexibility. Second, we consolidate findings on the molecular, physiological and functional changes in the PFC elicited by alcohol, that may contribute to cognitive flexibility deficits seen in AUD. Collectively, this approach identifies several key avenues for future research that will facilitate effective treatments to promote flexible behavior in the context of AUD, to reduce the risk of alcohol related harm, and to improve outcomes following AUD. This article is part of the Special Issue on "PFC circuit function in psychiatric disease and relevant models".
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Alcoholismo , Corteza Prefrontal , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/fisiología , Corteza Prefrontal/fisiopatología , Humanos , Animales , Alcoholismo/fisiopatología , Alcoholismo/psicología , Etanol/farmacología , Etanol/administración & dosificación , Cognición/fisiología , Cognición/efectos de los fármacos , Función Ejecutiva/fisiología , Función Ejecutiva/efectos de los fármacosRESUMEN
Radiation therapy and stereotactic radiosurgery are common treatments for brain malignancies. However, the impact of radiation on underlying neuronal circuits is poorly understood. In the prefrontal cortex (PFC), neurons communicate via action potentials that control cognitive processes, thus it is important to understand the impact of radiation on these circuits. Here we present a novel protocol to investigate the effect of radiation on the activity and survival of PFC networks in vitro. Escalating doses of radiation were applied to PFC slices using a robotic radiosurgery platform at a standard dose rate of 10 Gy/min. High-density multielectrode array recordings of radiated slices were collected to capture extracellular activity across 4,096 channels. Radiated slices showed an increase in firing rate, functional connectivity, and complexity. Graph-theoretic measures of functional connectivity were altered following radiation. These results were compared to pharmacologically induced epileptic slices where neural complexity was markedly elevated, and functional connections were strong but remained spatially focused. Finally, propidium iodide staining revealed a dose-dependent effect of radiation on apoptosis. These findings provide a novel assay to investigate the impacts of clinically relevant doses of radiation on brain circuits and highlight the acute effects of escalating radiation doses on PFC neurons.
Asunto(s)
Potenciales de Acción , Neuronas , Corteza Prefrontal , Animales , Corteza Prefrontal/efectos de la radiación , Corteza Prefrontal/fisiología , Neuronas/efectos de la radiación , Neuronas/fisiología , Potenciales de Acción/efectos de la radiación , Red Nerviosa/efectos de la radiación , Red Nerviosa/fisiología , Masculino , Electrodos , Ratas , Apoptosis/efectos de la radiación , Radiocirugia/métodosRESUMEN
The benefits of learning a motor skill extend to improved task-specific cognitive abilities. The mechanistic underpinnings of this motor-cognition relationship potentially rely on overlapping neural resources involved in both processes, an assumption lacking causal evidence. We hypothesize that interfering with prefrontal networks would inhibit concurrent motor skill performance, long-term learning and associated cognitive functions dependent on similar networks (transfer). We conducted a randomised, double-blinded, sham-controlled brain stimulation study using transcranial direct current stimulation (tDCS) in young adults spanning over three weeks to assess the role of the prefrontal regions in learning a complex balance task and long-term cognitive performance. Balance training combined with active tDCS led to higher performance variability in the trained task as compared to the sham group, impacting the process of learning a complex task without affecting the learning rate. Furthermore, active tDCS also positively influenced performance in untrained motor and cognitive tasks. The findings of this study help ascertaining the networks directly involved in learning a complex motor task and its implications on cognitive function. Hence, opening up the possibility of harnessing the observed frontal networks involved in resource mobilization in instances of aging, brain lesion/injury or dysfunction.
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Cognición , Corteza Prefrontal , Estimulación Transcraneal de Corriente Directa , Humanos , Corteza Prefrontal/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Cognición/fisiología , Masculino , Femenino , Método Doble Ciego , Adulto , Adulto Joven , Destreza Motora/fisiología , Aprendizaje/fisiologíaRESUMEN
Primates must adapt to changing environments by optimizing their behavior to make beneficial choices. At the core of adaptive behavior is the orbitofrontal cortex (OFC) of the brain, which updates choice value through direct experience or knowledge-based inference. Here, we identify distinct neural circuitry underlying these two separate abilities. We designed two behavioral tasks in which two male macaque monkeys updated the values of certain items, either by directly experiencing changes in stimulus-reward associations, or by inferring the value of unexperienced items based on the task's rules. Chemogenetic silencing of bilateral OFC combined with mathematical model-fitting analysis revealed that monkey OFC is involved in updating item value based on both experience and inference. In vivo imaging of chemogenetic receptors by positron emission tomography allowed us to map projections from the OFC to the rostromedial caudate nucleus (rmCD) and the medial part of the mediodorsal thalamus (MDm). Chemogenetic silencing of the OFC-rmCD pathway impaired experience-based value updating, while silencing the OFC-MDm pathway impaired inference-based value updating. Our results thus demonstrate dissociable contributions of distinct OFC projections to different behavioral strategies, and provide new insights into the neural basis of value-based adaptive decision-making in primates.
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Corteza Prefrontal , Animales , Masculino , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Conducta Animal/fisiología , Adaptación Psicológica/fisiología , Núcleo Caudado/fisiología , Núcleo Caudado/diagnóstico por imagen , Recompensa , Tomografía de Emisión de Positrones , Macaca mulatta , Vías Nerviosas/fisiología , Conducta de Elección/fisiología , Toma de Decisiones/fisiología , Tálamo/fisiología , Tálamo/diagnóstico por imagen , Mapeo Encefálico/métodosRESUMEN
Due to its central role in cognitive control, the dorso-lateral prefrontal cortex (dlPFC) has been the target of multiple brain modulation studies. In the context of the present pilot study, the dlPFC was the target of eight repeated neurofeedback (NF) sessions with functional near infrared spectroscopy (fNIRS) to assess the brain responses during NF and with functional and resting state magnetic resonance imaging (task-based fMRI and rsMRI) scanning. Fifteen healthy participants were recruited. Cognitive task fMRI and rsMRI were performed during the 1st and the 8th NF sessions. During NF, our data revealed an increased activity in the dlPFC as well as in brain regions involved in cognitive control and self-regulation learning (pFWE < 0.05). Changes in functional connectivity between the 1st and the 8th session revealed increased connectivity between the posterior cingulate cortex and the dlPFC, and between the posterior cingulate cortex and the dorsal striatum (pFWE < 0.05). Decreased left dlPFC-left insula connectivity was also observed. Behavioural results revealed a significant effect of hunger and motivation on the participant control feeling and a lower control feeling when participants did not identify an effective mental strategy, providing new insights on the effects of behavioural factors that may affect the NF learning.
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Corteza Prefontal Dorsolateral , Imagen por Resonancia Magnética , Neurorretroalimentación , Espectroscopía Infrarroja Corta , Humanos , Neurorretroalimentación/métodos , Masculino , Espectroscopía Infrarroja Corta/métodos , Femenino , Adulto , Imagen por Resonancia Magnética/métodos , Corteza Prefontal Dorsolateral/fisiología , Corteza Prefontal Dorsolateral/diagnóstico por imagen , Adulto Joven , Cuerpo Estriado/fisiología , Cuerpo Estriado/diagnóstico por imagen , Mapeo Encefálico/métodos , Proyectos Piloto , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Cognición/fisiologíaRESUMEN
Studies have shown that motor-cognitive dual task can greatly improve motor/cognitive function. However, the therapeutic effect of motor-cognitive dual task is still limited. How to improve dual-task performance is the key to solving this problem. Scalp acupuncture is a non-drug intervention method of traditional Chinese medicine to treat brain-derived diseases by acupuncturing the corresponding projection area of cerebral cortex function on the scalp. Studies have shown that scalp acupuncture helps improve neuronal damage and cognitive dysfunction and plays a neuroprotective function in central nervous system diseases. However, no relevant studies have discussed the synergistic gain effect of motor-cognitive dual task and scalp acupuncture. Therefore, this protocol aims to demonstrate the standardized operation of scalp acupuncture synchronizing motor-cognitive dual task and motor-cognitive dual task and compares the differences between these two tasks in healthy subjects through a randomized cross-over trial. This protocol initially revealed the possible influence mechanism of scalp acupuncture synchronizing motor-cognitive dual task on cognitive performance, gait control, and cortical brain function, which can provide new ideas and a theoretical basis for clinical exploration of new and effective non-drug treatment of integrated Chinese and Western medicine.
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Terapia por Acupuntura , Marcha , Corteza Prefrontal , Cuero Cabelludo , Humanos , Cuero Cabelludo/fisiología , Terapia por Acupuntura/métodos , Corteza Prefrontal/fisiología , Marcha/fisiología , Cognición/fisiología , Adulto , Estudios Cruzados , MasculinoRESUMEN
Acetylcholine regulates various cognitive functions through broad cholinergic innervation. However, specific cholinergic subpopulations, circuits and molecular mechanisms underlying recognition memory remain largely unknown. Here we show that Ngfr+ cholinergic neurons in the substantia innominate (SI)/nucleus basalis of Meynert (nBM)-medial prefrontal cortex (mPFC) circuit selectively underlies recency judgements. Loss of nerve growth factor receptor (Ngfr-/- mice) reduced the excitability of cholinergic neurons in the SI/nBM-mPFC circuit but not in the medial septum (MS)-hippocampus pathway, and impaired temporal order memory but not novel object and object location recognition. Expression of Ngfr in Ngfr-/- SI/nBM restored defected temporal order memory. Fiber photometry revealed that acetylcholine release in mPFC not only predicted object encounters but also mediated recency judgments of objects, and such acetylcholine release was absent in Ngfr-/- mPFC. Chemogenetic and optogenetic inhibition of SI/nBM projection to mPFC in ChAT-Cre mice diminished mPFC acetylcholine release and deteriorated temporal order recognition. Impaired cholinergic activity led to a depolarizing shift of GABAergic inputs to mPFC pyramidal neurons, due to disturbed KCC2-mediated chloride gradients. Finally, potentiation of acetylcholine signaling upregulated KCC2 levels, restored GABAergic driving force and rescued temporal order recognition deficits in Ngfr-/- mice. Thus, NGFR-dependent SI/nBM-mPFC cholinergic circuit underlies temporal order recognition memory.
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Acetilcolina , Neuronas Colinérgicas , Corteza Prefrontal , Animales , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/fisiología , Acetilcolina/metabolismo , Ratones , Masculino , Ratones Noqueados , Reconocimiento en Psicología/fisiología , Núcleo Basal de Meynert/metabolismo , Núcleo Basal de Meynert/fisiología , Ratones Endogámicos C57BL , Células Piramidales/metabolismo , Células Piramidales/fisiología , Hipocampo/metabolismo , Receptores de Factor de Crecimiento NerviosoRESUMEN
BACKGROUND: Our previous study synthesized the analgesic effects of repetitive Transcranial Magnetic Stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) trials up to 2019. There has been a significant increase in pain trials in the past few years, along with methodological variabilities such as sample size, stimulation intensity, and rTMS paradigms. OBJECTIVES/METHODS: This study therefore updated the effects of DLPFC-rTMS on chronic pain and quantified the impact of methodological differences across studies. RESULTS: A total of 36 studies were included. Among them, 26 studies were clinical trials (update = 9, 307/711 patients), and 10 (update = 1, 34/249 participants) were provoked pain studies. The updated meta-analysis does not support an effect on neuropathic pain after including the additional trials (pshort-term = 0.20, pmid-term = 0.50). However, there is medium-to-large analgesic effect in migraine trials extending up to six weeks follow-up (SMDmid-term = -0.80, SMDlong-term = -0.51), that was not previously reported. Methodological differences wthine the studies were considered. DLPFC-rTMS also induces potential improvement in the emotional aspects of pain (SMDshort-term = -0.28). CONCLUSIONS: The updated systematic meta-analysis continues to support analgesic effects for chronic pain overall. However, the updated results no longer support DLPFC-rTMS for pain relief in neuropathic pain, and do supports DLPFC-rTMS in the management of migraine. There is also evidence for DLPFC-rTMS to improve emotional aspects of pain.
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Corteza Prefontal Dorsolateral , Estimulación Magnética Transcraneal , Humanos , Estimulación Magnética Transcraneal/métodos , Corteza Prefontal Dorsolateral/fisiología , Manejo del Dolor/métodos , Dolor Crónico/terapia , Neuralgia/terapia , Corteza Prefrontal/fisiología , Corteza Prefrontal/fisiopatologíaRESUMEN
Academic achievement is a critical measure of intellectual ability, prompting extensive research into cognitive tasks as potential predictors. Neuroimaging technologies, such as functional near-infrared spectroscopy (fNIRS), offer insights into brain hemodynamics, allowing understanding of the link between cognitive performance and academic achievement. Herein, we explored the association between cognitive tasks and academic achievement by analyzing prefrontal fNIRS signals. A novel quantum annealer (QA) feature selection algorithm was applied to fNIRS data to identify cognitive tasks correlated with CSAT scores. Twelve features (signal mean, median, variance, peak, number of peaks, sum of peaks, range, minimum, kurtosis, skewness, standard deviation, and root mean square) were extracted from fNIRS signals at two time windows (10- and 60-s) to compare results from various feature variable conditions. The feature selection results from the QA-based and XGBoost regressor algorithms were compared to validate the former's performance. In a two-step validation process using multiple linear regression models, model fitness (adjusted R2) and model prediction error (RMSE) values were calculated. The quantum annealer demonstrated comparable performance to classical machine learning models, and specific cognitive tasks, including verbal fluency, recognition, and the Corsi block tapping task, were correlated with academic achievement. Group analyses revealed stronger associations between Tower of London and N-back tasks with higher CSAT scores. Quantum annealing algorithms have significant potential in feature selection using fNIRS data, and represents a novel research approach. Future studies should explore predictors of academic achievement and cognitive ability.
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Algoritmos , Cognición , Corteza Prefrontal , Espectroscopía Infrarroja Corta , Humanos , Espectroscopía Infrarroja Corta/métodos , Cognición/fisiología , Masculino , Femenino , Corteza Prefrontal/fisiología , Corteza Prefrontal/diagnóstico por imagen , Adulto , Adulto Joven , Aprendizaje AutomáticoRESUMEN
Prefrontal cortical activity represents stimuli in working memory tasks in a low-dimensional manifold that transforms over the course of a trial. Such transformations reflect specific cognitive operations, so that, for example, the rotation of stimulus representations is thought to reduce interference by distractor stimuli. Here we show that rotations occur in the low-dimensional activity space of prefrontal neurons in naïve male monkeys (Macaca mulatta), while passively viewing familiar stimuli. Moreover, some aspects of these rotations remain remarkably unchanged after training to perform working memory tasks. Significant training effects are still present in population dynamics, which further distinguish correct and error trials during task execution. Our results reveal automatic functions of prefrontal neural circuits allow transformations that may aid cognitive flexibility.
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Macaca mulatta , Memoria a Corto Plazo , Neuronas , Corteza Prefrontal , Animales , Corteza Prefrontal/fisiología , Corteza Prefrontal/citología , Masculino , Neuronas/fisiología , Memoria a Corto Plazo/fisiología , Cognición/fisiología , Estimulación LuminosaRESUMEN
The executive control process of monitoring information in working memory depends on the mid-dorsolateral prefrontal cortical region (cytoarchitectonic areas 46 and 9/46) in interaction with the hippocampal memory system. Anatomical studies demonstrated strong connectivity between the mid-dorsolateral prefrontal cortex and the medial parietal area PGm that lies on the precuneus. Area PGm is also strongly connected with the attentional system on the lateral inferior parietal lobule (area PG) and the limbic retrosplenial/posterior cingulate region that interacts with the hippocampal memory system. Thus, in terms of anatomical connectivity, area PGm appears to be a critical node for the integration of executive control processing from the prefrontal cortex with the online attentional and memory related processing. This hypothesis was tested in macaque monkeys with the crossed unilateral lesion methodology. A unilateral lesion in the mid-dorsolateral prefrontal cortex was combined with a unilateral lesion in area PGm in the opposite hemisphere. The results demonstrated an impairment on the externally ordered working memory task that assesses the monitoring of information in working memory. Thus, the medial parietal area PGm is a critical node in mediating the functional interaction between the prefrontal region for the executive control process of monitoring information and the memory system.
Asunto(s)
Memoria a Corto Plazo , Lóbulo Parietal , Animales , Memoria a Corto Plazo/fisiología , Lóbulo Parietal/fisiología , Masculino , Vías Nerviosas/fisiología , Macaca mulatta , Corteza Prefontal Dorsolateral/fisiología , Corteza Prefrontal/fisiologíaRESUMEN
The orbitofrontal cortex (OFC) is crucial for tracking various aspects of expected outcomes, thereby helping to guide choices and support learning. Our previous study showed that the effects of reward timing and size on the activity of single units in OFC were dissociable when these attributes were manipulated independently ( Roesch et al., 2006). However, in real-life decision-making scenarios, outcome features often change simultaneously, so here we investigated how OFC neurons in male rats integrate information about the timing and identity (flavor) of reward and respond to changes in these features, according to whether they were changed simultaneously or separately. We found that a substantial number of OFC neurons fired differentially to immediate versus delayed reward and to the different reward flavors. However, contrary to the previous study, selectivity for timing was strongly correlated with selectivity for identity. Taken together with the previous research, these results suggest that when reward features are correlated, OFC tends to "pack" them into unitary constructs, whereas when they are independent, OFC tends to "crack" them into separate constructs. Furthermore, we found that when both reward timing and flavor were changed, reward-responsive OFC neurons showed unique activity patterns preceding and during the omission of an expected reward. Interestingly, this OFC activity is similar and slightly preceded the ventral tegmental area dopamine (VTA DA) activity observed in a previous study ( Takahashi et al., 2023), consistent with the role of OFC in providing predictive information to VTA DA neurons.