LIVIVO - Das Suchportal für Lebenswissenschaften

switch to English language
Erweiterte Suche

Ihre letzten Suchen

  1. AU="Das, Anup"
  2. AU=Su Li
  3. AU="Ekobena, Pierre"
  4. AU="Wilson, Colin H"
  5. AU="Salvato, M"
  6. AU="Hense, Peter"
  7. AU="Chien, Jung-Ting"
  8. AU="Rashidi, Muhammad Mahdi"
  9. AU="Gryton, Igal"
  10. AU="Carvajal, Zaira Y García"
  11. AU="Li, Kaixun"
  12. AU="Khuituan, Pissared"
  13. AU="L.Milano, "
  14. AU="Chandramouli, Vaishnavi"
  15. AU="Jose Luis Lavín"
  16. AU="Csályi, Kitti"
  17. AU="Orobello, Nicklas C"
  18. AU=Kim Chang H.
  19. AU="Livingston, Abel"
  20. AU="DeKoven, Mitchell P"
  21. AU="Kubota, Katsumi"

Suchergebnis

Treffer 1 - 10 von insgesamt 292

Suchoptionen

  1. Artikel: Hippocampal-parietal cortex causal directed connectivity during human episodic memory formation: Replication across three experiments.

    Das, Anup / Menon, Vinod

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Hippocampus-parietal cortex circuits are thought to play a crucial role in memory and attention, but their neural basis remains poorly understood. We employed intracranial EEG from 96 participants (51 females) to investigate the neurophysiological ... ...

    Abstract Hippocampus-parietal cortex circuits are thought to play a crucial role in memory and attention, but their neural basis remains poorly understood. We employed intracranial EEG from 96 participants (51 females) to investigate the neurophysiological underpinning of these circuits across three memory tasks spanning verbal and spatial domains. We uncovered a consistent pattern of higher causal directed connectivity from the hippocampus to both lateral parietal cortex (supramarginal and angular gyrus) and medial parietal cortex (posterior cingulate cortex) in the delta-theta band during memory encoding and recall. This connectivity was independent of activation or suppression states in the hippocampus or parietal cortex. Crucially, directed connectivity from the supramarginal gyrus to the hippocampus was enhanced in participants with higher memory recall, highlighting its behavioral significance. Our findings align with the attention-to-memory model, which posits that attention directs cognitive resources toward pertinent information during memory formation. The robustness of these results was demonstrated through Bayesian replication analysis of the memory encoding and recall periods across the three tasks. Our study sheds light on the neural basis of casual signaling within hippocampus-parietal circuits, broadening our understanding of their critical roles in human cognition.
    Sprache Englisch
    Erscheinungsdatum 2024-03-21
    Erscheinungsland United States
    Dokumenttyp Preprint
    DOI 10.1101/2023.11.07.566056
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  2. Artikel: Electrophysiological dynamics of a triple network model of cognitive control: A multi-experiment replication.

    Das, Anup / Menon, Vinod

    bioRxiv : the preprint server for biology

    2024  

    Abstract: Dynamic interactions between large-scale brain networks are thought to underpin human cognitive processes, but their underlying electrophysiological dynamics remain unknown. The triple network model, which highlights the salience, default mode, and ... ...

    Abstract Dynamic interactions between large-scale brain networks are thought to underpin human cognitive processes, but their underlying electrophysiological dynamics remain unknown. The triple network model, which highlights the salience, default mode, and frontoparietal networks, provides a fundamental framework for understanding these interactions. To unravel the electrophysiological mechanisms underlying these network dynamics, we utilized intracranial EEG recordings from 177 participants across four distinct memory experiments. Our findings revealed a consistent pattern of directed information flow from the anterior insula, a key node of the salience network, to both the default mode and frontoparietal networks. Notably, this pattern of information transmission was observed regardless of the nature of the tasks, whether they involved externally driven stimuli during encoding or internally governed processes during free recall. Moreover, the directed information flow from the anterior insula to the other networks was present irrespective of the activation or suppression states of individual network nodes. Furthermore, we observed a specific suppression of high-gamma power in the posterior cingulate cortex/precuneus node of the default mode network during memory encoding, but not recall, suggesting a task-specific functional down-regulation of this region. Crucially, these results were reliably replicated across all four experiments, underscoring the robustness and generalizability of our findings. Our study significantly advances the understanding of how coordinated neural network interactions underpin cognitive operations and highlights the critical role of the anterior insula in orchestrating the dynamics of large-scale brain networks. These findings have important implications for elucidating the neural basis of cognitive control and its potential disruptions in various neurological and psychiatric disorders.
    Sprache Englisch
    Erscheinungsdatum 2024-04-20
    Erscheinungsland United States
    Dokumenttyp Preprint
    DOI 10.1101/2024.02.28.582593
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  3. Artikel ; Online: The Hiring of Labour for Field Cultivation: A Study in the Brahmaputra Valley of Northeast India

    Das, Anup Kumar

    International Journal of Rural Management. 2023 Aug., v. 19, no. 2 p.274-297

    2023  

    Abstract: On the basis of household-level data, the present study examines the hiring of farm labour in the Brahmaputra Valley of Assam in the north-eastern part of India. By adopting a multi-stage sampling technique, the primary data were collected from 237 ... ...

    Abstract On the basis of household-level data, the present study examines the hiring of farm labour in the Brahmaputra Valley of Assam in the north-eastern part of India. By adopting a multi-stage sampling technique, the primary data were collected from 237 randomly selected field crop cultivating households located in the lower, upper and central parts of the Brahmaputra Valley. The hiring of labour for field cultivation is extensive among the sample farm households of all size groups, but it varies across locations and activities. There are three forms of farm labour hiring, among which the hiring of labour on daily basis is common and pre-dominant. The wage of farm labourers is not same across activities, sex and locations. The estimation of independent double hurdle model depicts the farm size, type of cultivator and age of head of the household as the common factors that affect both the adoption and the extent of hiring of farm labour. The availability of family labour is another factor that affects the extent of hiring of farm labour.
    Schlagwörter farm labor ; farm size ; farms ; field crops ; hiring ; models ; India ; Agriculture ; hired farm labour ; Brahmaputra Valley ; double hurdle model
    Sprache Englisch
    Erscheinungsverlauf 2023-08
    Umfang p. 274-297.
    Erscheinungsort SAGE Publications
    Dokumenttyp Artikel ; Online
    ZDB-ID 2210261-9
    ISSN 0973-0680 ; 0973-0052
    ISSN (online) 0973-0680
    ISSN 0973-0052
    DOI 10.1177/09730052221097187
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

  4. Artikel ; Online: Concurrent- and After-Effects of Medial Temporal Lobe Stimulation on Directed Information Flow to and from Prefrontal and Parietal Cortices during Memory Formation.

    Das, Anup / Menon, Vinod

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2023  Band 43, Heft 17, Seite(n) 3159–3175

    Abstract: Electrical stimulation of the medial temporal lobe (MTL) has the potential to uncover causal circuit mechanisms underlying memory function. However, little is known about how MTL stimulation alters information flow with frontoparietal cortical regions ... ...

    Abstract Electrical stimulation of the medial temporal lobe (MTL) has the potential to uncover causal circuit mechanisms underlying memory function. However, little is known about how MTL stimulation alters information flow with frontoparietal cortical regions implicated in episodic memory. We used intracranial EEG recordings from humans (14 participants, 10 females) to investigate how MTL stimulation alters directed information flow between MTL and PFC and between MTL and posterior parietal cortex (PPC). Participants performed a verbal episodic memory task during which they were presented with words and asked to recall them after a delay of ∼20 s; 50 Hz stimulation was applied to MTL electrodes on selected trials during memory encoding. Directed information flow was examined using phase transfer entropy. Behaviorally, we observed that MTL stimulation reduced memory recall. MTL stimulation decreased top-down PFC→MTL directed information flow during both memory encoding and subsequent memory recall, revealing aftereffects more than 20 s after end of stimulation. Stimulation suppressed top-down PFC→MTL influences to a greater extent than PPC→MTL. Finally, MTL→PFC information flow on stimulation trials was significantly lower for successful, compared with unsuccessful, memory recall; in contrast, MTL→ventral PPC information flow was higher for successful, compared with unsuccessful, memory recall. Together, these results demonstrate that the effects of MTL stimulation are behaviorally, regionally, and directionally specific, that MTL stimulation selectively impairs directional signaling with PFC, and that causal MTL-ventral PPC circuits support successful memory recall. Findings provide new insights into dynamic casual circuits underling episodic memory and their modulation by MTL stimulation.
    Mesh-Begriff(e) Female ; Humans ; Brain Mapping/methods ; Prefrontal Cortex/physiology ; Temporal Lobe/physiology ; Parietal Lobe/physiology ; Memory, Episodic ; Magnetic Resonance Imaging/methods
    Sprache Englisch
    Erscheinungsdatum 2023-03-24
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.1728-22.2023
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  5. Artikel ; Online: Replicable patterns of causal information flow between hippocampus and prefrontal cortex during spatial navigation and spatial-verbal memory formation.

    Das, Anup / Menon, Vinod

    Cerebral cortex (New York, N.Y. : 1991)

    2022  Band 32, Heft 23, Seite(n) 5343–5361

    Abstract: Interactions between the hippocampus and prefrontal cortex (PFC) play an essential role in both human spatial navigation and episodic memory, but the underlying causal flow of information between these regions across task domains is poorly understood. ... ...

    Abstract Interactions between the hippocampus and prefrontal cortex (PFC) play an essential role in both human spatial navigation and episodic memory, but the underlying causal flow of information between these regions across task domains is poorly understood. Here we use intracranial EEG recordings and spectrally resolved phase transfer entropy to investigate information flow during two different virtual spatial navigation and memory encoding/recall tasks and examine replicability of information flow patterns across spatial and verbal memory domains. Information theoretic analysis revealed a higher causal information flow from hippocampus to lateral PFC than in the reverse direction. Crucially, an asymmetric pattern of information flow was observed during memory encoding and recall periods of both spatial navigation tasks. Further analyses revealed frequency specificity of interactions characterized by greater bottom-up information flow from hippocampus to PFC in delta-theta band (0.5-8 Hz); in contrast, top-down information flow from PFC to hippocampus was stronger in beta band (12-30 Hz). Bayesian analysis revealed a high degree of replicability between the two spatial navigation tasks (Bayes factor > 5.46e+3) and across tasks spanning the spatial and verbal memory domains (Bayes factor > 7.32e+8). Our findings identify a domain-independent and replicable frequency-dependent feedback loop engaged during memory formation in the human brain.
    Mesh-Begriff(e) Humans ; Spatial Navigation ; Bayes Theorem ; Spatial Memory ; Hippocampus ; Prefrontal Cortex
    Sprache Englisch
    Erscheinungsdatum 2022-01-06
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 1077450-6
    ISSN 1460-2199 ; 1047-3211
    ISSN (online) 1460-2199
    ISSN 1047-3211
    DOI 10.1093/cercor/bhac018
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  6. Artikel ; Online: A distributed land cover classification of FP and CP SAR observation using MapReduce-based multi-layer perceptron algorithm over the Mumbai mangrove region of India

    Roy, Sukanta / Das, Anup / Omkar, Subbaramajois Narasipur

    International Journal of Remote Sensing. 2023 Mar. 04, v. 44, no. 5 p.1510-1532

    2023  

    Abstract: Globally, the rapid loss of mangrove forests often creates long-lasting environmental damage alongside coastlines, mudflats, and river banks. All-weather, physical monitoring of such areas is almost impossible because of inaccessibility to swampy areas ... ...

    Abstract Globally, the rapid loss of mangrove forests often creates long-lasting environmental damage alongside coastlines, mudflats, and river banks. All-weather, physical monitoring of such areas is almost impossible because of inaccessibility to swampy areas and a hostile substrate. Subsequently, conventional field surveys are relatively unavailable to monitor human encroachment in coastal areas like the Mumbai mangrove region of India. In this context, the polarimetric synthetic aperture radar (PolSAR) remote sensing tool becomes a potential candidate for mangrove conservation and management. Since the Mumbai mangrove region of India exists over the extensive land cover, the large-scale classification can articulate the continuous encroachment because of the location of human settlements or activities across this metropolitan coastal city. For this, the traditional algorithms need the essential improvisation to apply for large-scale data analysis, aiming simultaneously at getting the highest decisive and time efficiency. Here, we introduce a shallow learning model of MapReduce-based Multi-Layer Perception (MLP) algorithm to classify the hybrid compact polarimetric (CP) and fully polarimetric (FP) feature space. Even though a shallow learning model of the automated method is easily scalable, it requires a distinctive shallow learnable feature set for better land cover classification. In this effort, this paper investigates the efficacy of derived feature space compared to direct polarimetric measurements of sensors and shows that the shallow learnable feature set is more effective with both CP & FP observations. Simultaneously, the relevancy of the proposed distributed model of MLP is also justified compared to distributed extreme learning machine (DELM) algorithm and provides a practically implementable scaled-MLP algorithm of shallow learning model. Ultimately, this paper comes up with a better polarimetric signature of land types for both the CP and FP datasets, which can be used in an alternative manner as per data availability for a multi-sensor data analysis.
    Schlagwörter algorithms ; automation ; data collection ; humans ; land cover ; models ; polarimetry ; synthetic aperture radar ; India ; Polarimetric SAR ; Landuse - landcover ; neural networks ; mangrove
    Sprache Englisch
    Erscheinungsverlauf 2023-0304
    Umfang p. 1510-1532.
    Erscheinungsort Taylor & Francis
    Dokumenttyp Artikel ; Online
    ZDB-ID 1497529-4
    ISSN 1366-5901 ; 0143-1161
    ISSN (online) 1366-5901
    ISSN 0143-1161
    DOI 10.1080/01431161.2023.2185114
    Datenquelle NAL Katalog (AGRICOLA)

    Zusatzmaterialien

    Kategorien

  7. Artikel ; Online: Sensing and Automation Technologies for Ornamental Nursery Crop Production: Current Status and Future Prospects.

    Mahmud, Md Sultan / Zahid, Azlan / Das, Anup Kumar

    Sensors (Basel, Switzerland)

    2023  Band 23, Heft 4

    Abstract: The ornamental crop industry is an important contributor to the economy in the United States. The industry has been facing challenges due to continuously increasing labor and agricultural input costs. Sensing and automation technologies have been ... ...

    Abstract The ornamental crop industry is an important contributor to the economy in the United States. The industry has been facing challenges due to continuously increasing labor and agricultural input costs. Sensing and automation technologies have been introduced to reduce labor requirements and to ensure efficient management operations. This article reviews current sensing and automation technologies used for ornamental nursery crop production and highlights prospective technologies that can be applied for future applications. Applications of sensors, computer vision, artificial intelligence (AI), machine learning (ML), Internet-of-Things (IoT), and robotic technologies are reviewed. Some advanced technologies, including 3D cameras, enhanced deep learning models, edge computing, radio-frequency identification (RFID), and integrated robotics used for other cropping systems, are also discussed as potential prospects. This review concludes that advanced sensing, AI and robotic technologies are critically needed for the nursery crop industry. Adapting these current and future innovative technologies will benefit growers working towards sustainable ornamental nursery crop production.
    Mesh-Begriff(e) Artificial Intelligence ; Prospective Studies ; Automation ; Technology ; Crop Production
    Sprache Englisch
    Erscheinungsdatum 2023-02-06
    Erscheinungsland Switzerland
    Dokumenttyp Journal Article ; Review
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s23041818
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  8. Konferenzbeitrag ; Buch ; Online: Accessing India's Open Educational Resources

    Das, Anup Kumar

    2020  

    Abstract: The presentation titled "Accessing India’s Open Educational Resources" was presented in the National Webinar on Awareness of eResources and Their Access by the Academic Community to overcome the COVID19 Pandemic, organized by Sonamukhi College, Bankura, ... ...

    Abstract The presentation titled "Accessing India’s Open Educational Resources" was presented in the National Webinar on Awareness of eResources and Their Access by the Academic Community to overcome the COVID19 Pandemic, organized by Sonamukhi College, Bankura, West Bengal, India on 21st September 2020. The event was organized to celebrate the International Open Access Week 2020.
    Schlagwörter Open Educational Resources ; OER ; Open Content ; Open Access ; NEP2020 ; National Education Policy ; India ; South Asia ; Ministry of Education ; Asia ; Open Courseware ; covid19
    Sprache Englisch
    Erscheinungsdatum 2020-09-21
    Erscheinungsland eu
    Dokumenttyp Konferenzbeitrag ; Buch ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

    Zusatzmaterialien

    Kategorien

  9. Artikel ; Online: Asymmetric Frequency-Specific Feedforward and Feedback Information Flow between Hippocampus and Prefrontal Cortex during Verbal Memory Encoding and Recall.

    Das, Anup / Menon, Vinod

    The Journal of neuroscience : the official journal of the Society for Neuroscience

    2021  Band 41, Heft 40, Seite(n) 8427–8440

    Abstract: Hippocampus and prefrontal cortex (PFC) circuits are thought to play a prominent role in human episodic memory, but the precise nature, and electrophysiological basis, of directed information flow between these regions and their role in verbal memory ... ...

    Abstract Hippocampus and prefrontal cortex (PFC) circuits are thought to play a prominent role in human episodic memory, but the precise nature, and electrophysiological basis, of directed information flow between these regions and their role in verbal memory formation has remained elusive. Here we investigate nonlinear causal interactions between hippocampus and lateral PFC using intracranial EEG recordings (26 participants, 16 females) during verbal memory encoding and recall tasks. Direction-specific information theoretic analysis revealed higher causal information flow from the hippocampus to PFC than in the reverse direction. Crucially, this pattern was observed during both memory encoding and recall, and the strength of causal interactions was significantly greater during memory task performance than resting baseline. Further analyses revealed frequency specificity of interactions with greater causal information flow from hippocampus to the PFC in the delta-theta frequency band (0.5-8 Hz); in contrast, PFC to hippocampus causal information flow were stronger in the beta band (12-30 Hz). Across all hippocampus-PFC electrode pairs, propagation delay between the source and target signals was estimated to be 17.7 ms, which is physiologically meaningful and corresponds to directional signal interactions on a timescale consistent with monosynaptic influence. Our findings identify distinct asymmetric feedforward and feedback signaling mechanisms between the hippocampus and PFC and their dissociable roles in memory recall, demonstrate that these regions preferentially use different frequency channels, and provide novel insights into the electrophysiological basis of directed information flow during episodic memory formation in the human brain.
    Mesh-Begriff(e) Adolescent ; Adult ; Biofeedback, Psychology/physiology ; Drug Resistant Epilepsy/physiopathology ; Drug Resistant Epilepsy/surgery ; Electroencephalography/methods ; Female ; Hippocampus/physiology ; Humans ; Male ; Mental Recall/physiology ; Middle Aged ; Prefrontal Cortex/physiology ; Verbal Learning/physiology ; Young Adult
    Sprache Englisch
    Erscheinungsdatum 2021-08-25
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 604637-x
    ISSN 1529-2401 ; 0270-6474
    ISSN (online) 1529-2401
    ISSN 0270-6474
    DOI 10.1523/JNEUROSCI.0802-21.2021
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

  10. Artikel ; Online: Causal dynamics and information flow in parietal-temporal-hippocampal circuits during mental arithmetic revealed by high-temporal resolution human intracranial EEG.

    Das, Anup / Menon, Vinod

    Cortex; a journal devoted to the study of the nervous system and behavior

    2021  Band 147, Seite(n) 24–40

    Abstract: Mental arithmetic involves distributed brain regions spanning parietal and temporal cortices, yet little is known about the neural dynamics of causal functional circuits that link them. Here we use high-temporal resolution (1000 Hz sampling rate) ... ...

    Abstract Mental arithmetic involves distributed brain regions spanning parietal and temporal cortices, yet little is known about the neural dynamics of causal functional circuits that link them. Here we use high-temporal resolution (1000 Hz sampling rate) intracranial EEG from 35 participants, 362 electrodes, and 1727 electrode pairs, to investigate dynamic causal circuits linking posterior parietal cortex (PPC) with ventral temporal-occipital cortex and hippocampal regions which constitute the perceptual, visuospatial, and mnemonic building blocks of mental arithmetic. Nonlinear phase transfer entropy measures capable of capturing information flow identified dorsal PPC as a causal inflow hub during mental arithmetic, with strong causal influences from fusiform gyrus in ventral temporal-occipital cortex as well as the hippocampus. Net causal inflow into dorsal PPC was significantly higher during mental arithmetic, compared to both resting-state and verbal memory recall. Our analysis also revealed functional heterogeneity of casual signaling in the PPC, with greater net causal inflow into the dorsal PCC, compared to ventral PPC. Additionally, the strength of causal influences was significantly higher on dorsal, compared to ventral, PPC from the hippocampus, and ventral temporal-occipital cortex during mental arithmetic, when compared to both resting-state and verbal memory recall. Our findings provide novel insights into dynamic neural circuits and hubs underlying numerical problem solving and reveal neurophysiological circuit mechanisms by which both the visual number form processing and declarative memory systems dynamically engage the PPC during mental arithmetic.
    Mesh-Begriff(e) Brain Mapping ; Electrocorticography ; Hippocampus/physiology ; Humans ; Magnetic Resonance Imaging ; Mathematics ; Parietal Lobe/physiology
    Sprache Englisch
    Erscheinungsdatum 2021-12-17
    Erscheinungsland Italy
    Dokumenttyp Journal Article ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 280622-8
    ISSN 1973-8102 ; 0010-9452
    ISSN (online) 1973-8102
    ISSN 0010-9452
    DOI 10.1016/j.cortex.2021.11.012
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Zusatzmaterialien

    Kategorien

Zum Seitenanfang