Edvard I Moser, May‐Britt Moser, P. Andersen,
Certain kinds of learning may be related to potentiation of transmission at specific hippocampal synapses. We investigated whether transmission across the perforant-path/granule-cell synapses of the dentate gyrus is facilitated when rats are learning about novel objects in an open field during exploration. Such studies are complicated by the sensitivity of hippocampal field potentials to brain temperature change. To control for this, we have recorded both brain temperature and field potentials and ...
Tópico(s): Neural dynamics and brain function
1994 - Cold Spring Harbor Laboratory Press | Learning & Memory
Edvard I Moser, May‐Britt Moser, Per Andersen,
To investigate whether hippocampal synaptic transmission is enhanced during learning, we recorded synaptic field potentials in the dentate gyrus in response to stimulation of the perforant path in rats exploring a novel environment. Because these signals rapidly grow during brain temperature elevation, caused by any motor activity, the potentials were compared with signals sampled at similar brain temperatures after passive warming. Both the field excitatory postsynaptic potential (f-EPSP) and the ...
Tópico(s): Memory and Neural Mechanisms
1993 - Lippincott Williams & Wilkins | Neuroreport
Boaz Wultz, Terje Sagvolden, Edvard I Moser, May‐Britt Moser,
Spontaneously hypertensive rats (SHR) show a pervasive hyperactivity in several paradigms. Thus, these rats may be used as an animal model of childhood hyperactivity also called Attention-Deficit Hyperactivity Disorder. This disorder is frequently treated with psychomotor stimulant drugs, but little is known about the effects of such drugs on behavior. The present study investigated the behavioral effects of 1-24 mg/kg methylphenidate (Ritalin) on the exploratory behavior of male SHR and Wistar-Kyoto ...
Tópico(s): Neural and Behavioral Psychology Studies
1990 - Academic Press | Behavioral and Neural Biology
Edvard I Moser, May‐Britt Moser,
Long-term potentiation (LTP) has become a leading candidate mechanism for memory formation. The proposed link between LTP and memory rests primarily on a single type of behavioural evidence: disruption of learning by interventions that block critical steps in the induction of LTP. As such blockade may disrupt non-mnemonic functions also, the LTP–learning question should be approached with multiple strategies. One alternative approach is to determine whether hippocampus-dependent learning is blocked ...
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
1999 - Elsevier BV | Neuroscience & Biobehavioral Reviews
P. Andersen, Edvard I Moser, May‐Britt Moser, Mari Trommald,
Learning through exploration gives increased synaptic field potentials in the perforant path/dentate synapses, largely due to an activity-dependent brain temperature increase. After temperature compensation, spatial learning was associated with small, but significant, STP-like changes of the field potential lasting 20-30 min. A group of spatially trained adult rats showed faster spatial learning and about 10% higher basal dendritic spine density (LY-filled) compared to two control groups. With unchanged ...
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
1996 - Elsevier BV | Journal of Physiology-Paris
Edvard I Moser, May‐Britt Moser,
Abstract The hippocampus plays a crucial role in the encoding and retrieval of episodic memory. In this issue of Neuron , Nakazawa and coworkers show that synaptic modification in hippocampal CA3 neurons is critical for immediate storage of information, a key feature of episodic memory.
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
2003 - Cell Press | Neuron
Hill-Aina Steffenach, Robert S. Sloviter, Edvard I Moser, May‐Britt Moser,
Longitudinally oriented axon collaterals of CA3 pyramidal cells may be critical for integrating distributed information in the hippocampus. To investigate the possible role of this pathway in the retention of spatial memory, we made a single transversely oriented cut through the dorsal CA3 region of each hippocampus. Although the lesion involved <3% of the hippocampal volume, it nonetheless disrupted memory retention in a water maze in preoperatively trained rats. New learning in a different water ...
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
2002 - National Academy of Sciences | Proceedings of the National Academy of Sciences
Kirsten G. Kjelstrup, Frode A. Tuvnes, Hill-Aina Steffenach, Robert Murison, Edvard I Moser, May‐Britt Moser,
The hippocampus has a critical role in several fundamental memory operations, including the conditioning of fear to contextual information. We show that the hippocampus is necessary also for unconditioned fear, and that the involved circuitry is at the ventral pole of the hippocampus. Rats with selective hippocampal lesions failed to avoid open arms in an elevated plus-maze and had decreased neuroendocrine stress responses during confinement to a brightly lit chamber. These effects were reproduced ...
Tópico(s): Stress Responses and Cortisol
2002 - National Academy of Sciences | Proceedings of the National Academy of Sciences
Stefan Leutgeb, Jill K. Leutgeb, Edvard I Moser, May‐Britt Moser,
Abstract Environments with overlapping features are represented by distinct patterns of activity in the hippocampus, enabling information to be stored and retrieved with minimal interference. This orthogonalization of correlated inputs is thought to take place within the hippocampus itself. However, the orthogonalization process has been shown to take days to develop in CA1. This prolonged time course is in striking contrast to the fast encoding of behavioral memory by the hippocampus. To explore ...
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
2006 - Wiley | Hippocampus
Bruce L. McNaughton, Francesco P. Battaglia, Ole Jensen, Edvard I Moser, May‐Britt Moser,
Tópico(s): Sleep and Wakefulness Research
2006 - Nature Portfolio | Nature reviews. Neuroscience
Edvard I Moser, May‐Britt Moser, P. Lipa, M. R. Newton, Frank P. Houston, Carol A. Barnes, Bruce L. McNaughton,
One of several tenable hypotheses that can be proposed to explain the complex dynamics of spatially selective hippocampal neural activity postulates that the region of space over which a given cell receives its external input is actually much smaller than the classical ‘place field.’ According to this notion, the later portions of the field reflect some form of network hysteresis resulting from ‘reverberatory’ activity within reentrant, synaptically coupled cell assemblies within the hippocampus. ...
Tópico(s): Neural dynamics and brain function
2004 - Elsevier BV | Neuroscience
Marianne Fyhn, Sturla Molden, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
As the interface between hippocampus and neocortex, the entorhinal cortex is likely to play a pivotal role in memory. To determine how information is represented in this area, we measured spatial modulation of neural activity in layers of medial entorhinal cortex projecting to the hippocampus. Close to the postrhinal-entorhinal border, entorhinal neurons had stable and discrete multipeaked place fields, predicting the rat's location as accurately as place cells in the hippocampus. Precise positional ...
Tópico(s): Stress Responses and Cortisol
2004 - American Association for the Advancement of Science | Science
Charlotte N. Boccara, Francesca Sargolini, Veslemøy Hult Thoresen, Trygve Solstad, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
Tópico(s): Sleep and Wakefulness Research
2010 - Nature Portfolio | Nature Neuroscience
Rosamund F. Langston, James A. Ainge, Jonathan J. Couey, Cathrin B. Canto, Tale L. Bjerknes, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
In the adult brain, space and orientation are represented by an elaborate hippocampal-parahippocampal circuit consisting of head-direction cells, place cells, and grid cells. We report that a rudimentary map of space is already present when 2 1/2-week-old rat pups explore an open environment outside the nest for the first time. Head-direction cells in the pre- and parasubiculum have adultlike properties from the beginning. Place and grid cells are also present but evolve more gradually. Grid cells ...
Tópico(s): Neuroscience and Neuropharmacology Research
2010 - American Association for the Advancement of Science | Science
Edvard I Moser, May‐Britt Moser,
Abstract Not all areas of neuronal systems investigation have matured to the stage where computation can be understood at the microcircuit level. In mammals, insights into cortical circuit functions have been obtained for the early stages of sensory systems, where signals can be followed through networks of increasing complexity from the receptors to the primary sensory cortices. These studies have suggested how neurons and neuronal networks extract features from the external world, but how the ...
Tópico(s): Neuroscience and Neuropharmacology Research
2008 - Wiley | Hippocampus
Laura L Colgin, Edvard I Moser, May‐Britt Moser,
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
2008 - Elsevier BV | Trends in Neurosciences
Kirsten Brun Kjelstrup, Trygve Solstad, Vegard Heimly Brun, Torkel Hafting, Stefan Leutgeb, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
To determine how spatial scale is represented in the pyramidal cell population of the hippocampus, we recorded neural activity at multiple longitudinal levels of this brain area while rats ran back and forth on an 18-meter-long linear track. CA3 cells had well-defined place fields at all levels. The scale of representation increased almost linearly from <1 meter at the dorsal pole to approximately 10 meters at the ventral pole. The results suggest that the place-cell map includes the entire hippocampus ...
Tópico(s): Neurogenesis and neuroplasticity mechanisms
2008 - American Association for the Advancement of Science | Science
Vegard Heimly Brun, Stefan Leutgeb, Hui‐Qiu Wu, Robert Schwarcz, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
Place-specific firing in the hippocampus is determined by path integration-based spatial representations in the grid-cell network of the medial entorhinal cortex. Output from this network is conveyed directly to CA1 of the hippocampus by projections from principal neurons in layer III, but also indirectly by axons from layer II to the dentate gyrus and CA3. The direct pathway is sufficient for spatial firing in CA1, but it is not known whether similar firing can also be supported by the input from ...
Tópico(s): Traumatic Brain Injury and Neurovascular Disturbances
2008 - Cell Press | Neuron
Vegard Heimly Brun, Trygve Solstad, Kirsten Brun Kjelstrup, Marianne Fyhn, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
Abstract Grid cells are topographically organized in the sense that, within the dorsal part of the medial entorhinal cortex, the scale of the grid increases systematically with anatomical distance from the dorsal border of this brain area. The ventral limit of the spatial map is currently not known. To determine if the grid map extends into the intermediate and ventral parts of the medial entorhinal cortex, we recorded activity from entorhinal principal cells at multiple dorsoventral levels while ...
Tópico(s): Stress Responses and Cortisol
2008 - Wiley | Hippocampus
Marianne Fyhn, Torkel Hafting, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
Abstract The medial entorhinal cortex (EC) is a part of the neural network for the representation of self‐location in the rat. The key cell type of this system is the grid cell, whose multiple firing fields span the environment in a remarkably regular triangular or hexagonal pattern. The basic properties of grid cells and other cell types have been described, but the neuronal mechanisms responsible for the formation and maintenance of the place code remain elusive. These mechanisms can be investigated ...
Tópico(s): Neurogenesis and neuroplasticity mechanisms
2008 - Wiley | Hippocampus
Edvard I Moser, May‐Britt Moser,
The resting brain recapitulates activity patterns that occurred during a recent experience, possibly to aid long-term memory formation. Surprisingly, corresponding brain activity also occurs before an event happens. See Letter p.397 Place cells in the hippocampus track an animal's position in its environment. Previous work contends that sequential place-cell maps are produced during the first visit to a new area, and later consolidated at rest or during sleep. George Dragoi and Susumu Tonegawa report ...
Tópico(s): Neuroscience and Neuropharmacology Research
2011 - Nature Portfolio | Nature
Karel Ježek, Espen J. Henriksen, Alessandro Treves, Edvard I Moser, May‐Britt Moser,
Tópico(s): Neural dynamics and brain function
2011 - Nature Portfolio | Nature
C.B. Alme, Chenglin Miao, Karel Ježek, Alessandro Treves, Edvard I Moser, May‐Britt Moser,
Significance The hippocampus is thought to store a large number of experiences that, despite their similarity, can be individually retrieved with minimal interference. Studies have shown that place cells in hippocampal area CA3 form statistically independent representations of pairs of environments. It has remained unclear, however, whether CA3 place cells maintain this independence when the number of environments is increased. We recorded activity from CA3 in 11 environments with nearly identical ...
Tópico(s): Neuroinflammation and Neurodegeneration Mechanisms
2014 - National Academy of Sciences | Proceedings of the National Academy of Sciences
Tale L. Bjerknes, Edvard I Moser, May‐Britt Moser,
Local space is represented by a number of functionally specific cell types, including place cells in the hippocampus and grid cells, head direction cells, and border cells in the medial entorhinal cortex (MEC). These cells form a functional map of external space already at the time when rat pups leave the nest for the first time in their life, at the age of 2.5 weeks. However, while place cells have adult-like firing fields from the outset, grid cells have irregular and variable fields until the ...
Tópico(s): Neurogenesis and neuroplasticity mechanisms
2014 - Cell Press | Neuron
Kei M. Igarashi, Hiroshi Ito, Edvard I Moser, May‐Britt Moser,
Decades of neuroscience research have shed light on the hippocampus as a key structure for the formation of episodic memory. The hippocampus is divided into distinct subfields – CA1, CA2 and CA3. While accumulating evidence points to cellular and synaptic heterogeneity within each subfield, this heterogeneity has not received much attention in computational and behavioural studies and subfields have until recently been considered functionally uniform. However, a couple of recent studies have demonstrated ...
Tópico(s): Neural dynamics and brain function
2014 - Wiley | FEBS Letters
Tale L. Bjerknes, Rosamund F. Langston, Ingvild Ulsaker Kruge, Edvard I Moser, May‐Britt Moser,
Mammalian navigation is thought to depend on an internal map of space consisting of functionally specialized cells in the hippocampus and the surrounding parahippocampal cortices [1O'Keefe J. Dostrovsky J. The hippocampus as a spatial map. Preliminary evidence from unit activity in the freely-moving rat.Brain Res. 1971; 34: 171-175Crossref PubMed Scopus (3810) Google Scholar, 2Ranck J.B. Head direction cells in the deep cell layer of dorsal presubiculum in freely moving rats.in: Buzsáki G. Vanderwolf ...
Tópico(s): Sleep and Wakefulness Research
2014 - Elsevier BV | Current Biology
Sheng-Jia Zhang, Jing Ye, Jonathan J. Couey, Menno P. Witter, Edvard I Moser, May‐Britt Moser,
The mammalian space circuit is known to contain several functionally specialized cell types, such as place cells in the hippocampus and grid cells, head-direction cells and border cells in the medial entorhinal cortex (MEC). The interaction between the entorhinal and hippocampal spatial representations is poorly understood, however. We have developed an optogenetic strategy to identify functionally defined cell types in the MEC that project directly to the hippocampus. By expressing channelrhodopsin- ...
Tópico(s): Photoreceptor and optogenetics research
2013 - Royal Society | Philosophical Transactions of the Royal Society B Biological Sciences
Edvard I Moser, May‐Britt Moser, Yasser Roudi,
One of the major breakthroughs in neuroscience is the emerging understanding of how signals from the external environment are extracted and represented in the primary sensory cortices of the mammalian brain. The operational principles of the rest of the cortex, however, have essentially remained in the dark. The discovery of grid cells, and their functional organization, opens the door to some of the first insights into the workings of the association cortices, at a stage of neural processing where ...
Tópico(s): Neuroscience and Neuropharmacology Research
2013 - Royal Society | Philosophical Transactions of the Royal Society B Biological Sciences
Edvard I Moser, May‐Britt Moser,
An ultimate goal of neuroscience is to understand the mechanisms of mammalian intellectual functions, many of which are thought to depend extensively on the cerebral cortex. While this may have been considered a remote objective when Neuron was launched in 1988, neuroscience has now evolved to a stage where it is possible to decipher neural-circuit mechanisms in the deepest parts of the cortex, far away from sensory receptors and motoneurons. In this review, we show how studies of place cells in ...
Tópico(s): Memory and Neural Mechanisms
2013 - Cell Press | Neuron
Tora Bonnevie, Benjamin Dunn, Marianne Fyhn, Torkel Hafting, Dori Derdikman, John L. Kubie, Yasser Roudi, Edvard I Moser, May‐Britt Moser,
Tópico(s): Sleep and Wakefulness Research
2013 - Nature Portfolio | Nature Neuroscience