Theta-band phase locking during encoding leads to coordinated entorhinal-hippocampal replay

Precisely timed interactions between hippocampal and cortical neurons during replay epochs are thought to support learning. Indeed, research has shown that replay is associated with heightened hippocampal-cortical synchrony. Yet many caveats remain in our understanding. Namely, it remains unclear how this offline synchrony comes about, whether it is specific to particular behavioral states, and how-if at all-it relates to learning. In this study, we sought to address these questions by analyzing coordination between CA1 cells and neurons of the deep layers of the medial entorhinal cortex (dMEC) while rats learned a novel spatial task. During movement, we found a subset of dMEC cells that were particularly locked to hippocampal LFP theta-band oscillations and that were preferentially coordinated with hippocampal replay during offline periods. Further, dMEC synchrony with CA1 replay peaked ∼10 ms after replay initiation in CA1, suggesting that the distributed replay reflects extra-hippocampal information propagation and is specific to "offline" periods. Finally, theta-modulated dMEC cells showed a striking experience-dependent increase in synchronization with hippocampal replay trajectories, mirroring the animals' acquisition of the novel task and coupling to the hippocampal local field. Together, these findings provide strong support for the hypothesis that synergistic hippocampal-cortical replay supports learning and highlights phase locking to hippocampal theta oscillations as a potential mechanism by which such cross-structural synchrony comes about

„NORMAL IS NOT JUST ONE SPECIFIC EXPERIENCE“ WOMEN´S EXPERIENCES AND VIEW OF NORMAL BIRTH: A QUALITATIVE RESEARCH

To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked DownloadVerndun eðlilegra fæðinga hefur verið mikilvægt viðfangsefni innan ljósmóðurfræða síðustu áratugi. Þar er iðulega stillt upp mismunandi sýn læknisfræðinnar og ljósmóðurfræðinnar en sjónum sjaldnar beint að upplifun kvenna sjálfra og hvað fyrir þeim eðlileg fæðing er. Í þessari rannsókn var markmiðið að fá fram reynslu kvenna og sýn á eðlilega fæðingu. Aðferðafræði rannsóknarinnar er eigindleg og byggist á viðtölum við tíu konur, fjölbyrjur og frumbyrjur, sem eiga samtals nítján fæðingar að baki. Viðtölin eru greind með fyrirbærafræðilegri aðferð Vancouver-skólans. Við heildargreiningu á fyrirbærinu eðlileg fæðing er unnið úr reynslu allra kvennanna og spunninn sameiginlegur vefur. Undirstöðuþemað við úrvinnslu á sögum kvennanna er Að gera fæðingarreynsluna að sinni eðlilegu fæðingu. Í þeirri ferð er fólgin óvissa, þar sem eðlilegt er að fá hjálp og ef vel tekst til eru þar tækifæri til valdeflingar. Sjö meginþemu með undirþemum eru greind sem öll hafa áhrif innbyrðis á heildarupplifun og lýsingu á fyrirbærinu eðlileg fæðing. Þessi þemu eru eftirfarandi: að hafa stjórn, stuðningur ljósmóður, sameiginlegt verkefni, öryggi og umhverfi, reynsla af sársauka, að taka á móti eigin barni, ekki eðlileg fæðing. Í skilgreiningum fagfólks á eðlilegri fæðingu hafa jafnan andstæðurnar „inngrip“ og „ekki inngrip“ legið til grundvallar. Í hugum þeirra kvenna sem rætt var við í rannsókninni er þessi tvískipting ekki útgangspunktur eðlilegrar fæðingar. Allar konurnar líta svo á að þær eigi eðlilega fæðingu að baki – jafnvel náttúrulega fæðingu – þrátt fyrir fjölbreytt inngrip og ólíkar fæðingarsögur. Sýn þessara kvenna brýtur á vissan hátt upp hugtakið eðlileg fæðing eins og það hefur hingað til verið skilgreint innan ljósmóðurfræðinnar. Niðurstöður rannsóknarinnar styðja ljósmæður í að leggja einstaklingsbundnari skilning á mörk hins eðlilega, treysta á innsæisþekkingu og mæta konum á þeirra eigin forsendum í fæðingu. Rannsaka mætti hvernig tæknilegt, félagslegt og menningarlegt umhverfi barneignarþjónustu hefur áhrif á persónubundnar skilgreiningar á eðlilegri fæðingu.Protecting normal birth has for a number of years been an important and significant topic in midwifery. The contrasting visions of the medico-technical approach and the physio-social midwifery approach are regularly juxtaposed, but less space has been given to what women´views are and how they experience normal birth. This research explores women´s own perceptions of what normal birth is. The methodology of the research is qualitative and based on interviews with ten women, both multiparous and primiparous, who have given a total of nineteen births. Anlalysis of data was based on the Vancouver School of doing phenomenology. Through making a comprehensive analysis of the phenomenon of normal birth from the point of view of women, a collective multi- -voice construction of their normal birth was designed. The overriding theme which emerged was “Making birth your own normal birth experience.” This journey of birth is full of uncertainty, where it is normal to get help, but the experience can also be an empowering self-discovery. Seven central themes with sub themes emerged which are all inter-related. Together they make up the holistic experience of „ÞAÐ ER EKKI EITTHVAÐ EITT EÐLILEGT“ Reynsla og sýn kvenna á eðlilega fæðingu: Eigindleg rannsókn „NORMAL IS NOT JUST ONE SPECIFIC EXPERIENCE“ WOMEN´S EXPERIENCES AND VIEW OF NORMAL BIRTH: A QUALITATIVE RESEARCH LJÓSMÆÐRABLAÐIÐ - JÚLÍ 2018 39 normal birth. These themes are: to be in control, midwife´s support, a joint venture, safety and surroundings, experience of pain, to receive your child, not a normal birth. “Intervention” or “non- intervention” into the birth process, which is the critical dichotomy many birth professionals use to define normal birth, is not a central concern in the women´s experiences. All the women interviewed describe their births as normal – even natural – despite there having been varied interventions and birth stories at work. Their views critically challenge traditional definitions of normal birth. This may encourage us to consider more subjective and contextual approaches to defining normalcy. It vitalizes our reliance on our intuitive knowledge and prioritizes meeting women on their own terms in every birth experience. For future studies it would be interesting to explore techno - social and cultural aspects of maternity services on personal definitions of normal birth

Temporally delayed linear modelling (TDLM) measures replay in both animals and humans

There are rich structures in off-task neural activity which are hypothesised to reflect fundamental computations across a broad spectrum of cognitive functions. Here, we develop an analysis toolkit - Temporal Delayed Linear Modelling (TDLM) for analysing such activity. TDLM is a domain-general method for finding neural sequences that respect a pre-specified transition graph. It combines nonlinear classification and linear temporal modelling to test for statistical regularities in sequences of task-related reactivations. TDLM is developed on the non-invasive neuroimaging data and is designed to take care of confounds and maximize sequence detection ability. Notably, as a linear framework, TDLM can be easily extended, without loss of generality, to capture rodent replay in electrophysiology, including in continuous spaces, as well as addressing second-order inference questions, e.g., its temporal and spatial varying pattern. We hope TDLM will advance a deeper understanding of neural computation and promote a richer convergence between animal and human neuroscience

Reynsla kvenna af tvíburameðgöngu með áherslu á andlega líðan og stuðning ljósmæðra

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Intracellular Fas ligand in normal and malignant breast epithelium does not induce apoptosis in Fas-sensitive cells

Fas ligand (FasL) is expressed on some cancers and may play a role in the immune evasion of the tumour. We used immuno-histochemistry to study the expression of Fas and FasL in tissue samples from breast cancer patients, as well as normal breast tissue. Our results show that Fas and FasL are co-expressed both in normal tissue and in breast tumours. Fas and FasL mRNA were expressed in fresh normal and malignant breast tissue, as well as cultured breast epithelium and breast cancer cell lines. Flow cytometry analysis of live cells failed to detect FasL on the surface of normal or malignant breast cells; however, both stained positive for FasL after permeabilization. Fas was detected on the surface of normal breast cells and T47D and MCF-10A cell lines but only intracellularly in other breast cell lines tested. Neither normal breast epithelium nor breast cell lines induced Fas-dependent apoptosis in Jurkat cells. Finally, 20 tumour samples were stained for apoptosis. Few apoptotic cells were detected and there was no increase in apoptotic cells on the borders between tumour cells and lymphocytes. We conclude that FasL is expressed intracellularly in both normal and malignant breast epithelium and unlikely to be important for the immune evasion of breast tumours. © 2000 Cancer Research Campaign http://www.bjcancer.co

Episodic memory development: Bridging animal and human research

Human episodic memory is not functionally evident until about 2 years of age and continues to develop into the school years. Behavioral studies have elucidated this developmental timeline and its constituent processes. In tandem, lesion and neurophysiological studies in non-human primates and rodents have identified key neural substrates and circuit mechanisms that may underlie episodic memory development. Despite this progress, collaborative efforts between psychologists and neuroscientists remain limited, hindering progress. Here, we seek to bridge human and non-human episodic memory development research by offering a comparative review of studies using humans, non-human primates, and rodents. We highlight critical theoretical and methodological issues that limit cross-fertilization and propose a common research framework, adaptable to different species, that may facilitate cross-species research endeavors

Temporally delayed linear modelling (TDLM) measures replay in both animals and humans

There are rich structures in off-task neural activity which are hypothesised to reflect fundamental computations across a broad spectrum of cognitive functions. Here, we develop an analysis toolkit - Temporal Delayed Linear Modelling (TDLM) for analysing such activity. TDLM is a domain-general method for finding neural sequences that respect a pre-specified transition graph. It combines nonlinear classification and linear temporal modelling to test for statistical regularities in sequences of task-related reactivations. TDLM is developed on the non-invasive neuroimaging data and is designed to take care of confounds and maximize sequence detection ability. Notably, as a linear framework, TDLM can be easily extended, without loss of generality, to capture rodent replay in electrophysiology, including in continuous spaces, as well as addressing second-order inference questions, e.g., its temporal and spatial varying pattern. We hope TDLM will advance a deeper understanding of neural computation and promote a richer convergence between animal and human neuroscience

Coordinated grid and place cell replay during rest

Hippocampal replay has been hypothesized to underlie memory consolidation and navigational planning, yet the involvement of grid cells in replay is unknown. During replay we found grid cells to be spatially coherent with place cells, encoding locations 11 ms delayed relative to the hippocampus, with directionally modulated grid cells and forward replay exhibiting the greatest coherence with the CA1 area of the hippocampus. This suggests grid cells are engaged during the consolidation of spatial memories to the neocortex