Abstract Recollection is thought to be the hallmark of episodic memory. Here we provide evidence that hippocampus binds together diverse elements forming an event, allowing holistic recollection via pattern completion all elements. Participants learn complex ‘events’ from multiple overlapping pairs elements, and are tested on pairwise associations. At encoding, element ‘types’ (locations, people objects/animals) produce activation in distinct neocortical regions, while hippocampal activity...

Grid cells in the entorhinal cortex (EC) of rodents [1] and humans [2] fire a hexagonally distributed spatially periodic manner. In concert with other spatial medial temporal lobe (MTL) [3-6], they provide representation our location within an environment [7, 8] are specifically thought to allow represented be updated by self-motion [9]. Grid-like signals have been seen throughout autobiographical memory system [10], suggesting much more general role [11, 12]. may us move viewpoint...

Grid cells in the rodent medial entorhinal cortex exhibit remarkably regular spatial firing patterns that tessellate all environments visited by animal. Two theoretical mechanisms could generate this spatially periodic activity pattern have been proposed: oscillatory interference and continuous attractor dynamics. Although a variety of evidence has cited support each, some aspects two are complementary, suggesting combined model may best account for experimental data. The proposes grid is...

Memory retrieval is believed to involve a disparate network of areas, including medial prefrontal and temporal cortices, but the mechanisms underlying their coordination remain elusive. One suggestion that oscillatory coherence mediates inter-regional communication, implicating theta phase theta-gamma phase-amplitude coupling in mnemonic function across species. To examine this hypothesis, we used non-invasive whole-head magnetoencephalography (MEG) as participants retrieved location objects...

Events are thought to be stored in episodic memory as coherent representations, which the constituent elements bound together so that a cue can trigger reexperience of all via pattern completion. Negative emotional content strongly influence memory, but opposing theories predict strengthening or weakening coherence. Across series experiments, participants imagined number person-location-object events with half including negative element (e.g., an injured person), and was tested across within...

Significance Rodent hippocampal theta-band oscillations are observed throughout translational movement, implicating theta in the encoding of self-motion. Interestingly, increases power particularly prominent around movement onset. Here, we use intracranial recordings from epilepsy patients navigating a desktop virtual reality environment to demonstrate that is also increased human hippocampus onset and remainder movement. Importantly, these greater both before during longer paths, directly...

Decreases in low-frequency power (2-30 Hz) alongside high-frequency increases (>40 have been demonstrated to predict successful memory formation. Parsimoniously, this change the frequency spectrum can be explained by one factor, a tilt of (from steep flat) indicating engaged brain regions. A competing view is that contains several distinct oscillatory fingerprints, each serving different computations. Here, we contrast these two theories parallel magnetoencephalography (MEG)-intracranial...

Abstract Hippocampal theta oscillations have been implicated in associative memory humans. However, findings from electrophysiological studies using scalp electroencephalography or magnetoencephalography, and those intracranial are mixed. Here we asked 10 pre-surgical epilepsy patients undergoing recording, along with 21 participants magnetoencephalography recordings, to perform an task, examined whether hippocampal activity during encoding was predictive of subsequent performance. Across...

Hippocampal place cells in freely moving rodents display both theta phase precession and procession, which is thought to play important roles cognition, but the neural mechanism for producing shift remains largely unknown. Here, we show that firing rate adaptation within a continuous attractor network causes activity bump oscillate around external input, resembling sweeps of decoded position during locomotion. These forward backward naturally account procession individual neurons,...

Fluent retrieval and execution of movement sequences is essential for daily activities, but the neural mechanisms underlying sequence planning remain elusive. Here participants learned finger press with different orders timings reproduced them in a magneto-encephalography (MEG) scanner. We classified MEG patterns each examined pattern dynamics during preparation production. Our results demonstrate "competitive queuing" (CQ) upcoming action representations, extending previous computational...

Hippocampal theta oscillations have been implicated in spatial memory function both rodents and humans. What is less clear how hippocampal interacts with higher frequency to support long-term memory. Here we asked 10 presurgical epilepsy patients undergoing intracranial EEG recording perform a task desktop virtual reality found that increased power two discrete bands ("low" 2-5 Hz "high" 6-11 Hz) during cued retrieval was associated improved performance. Similarly, coupling between "low"...

Frontotemporal dysconnectivity is a key pathology in schizophrenia. The specific nature of this unknown, but animal models imply dysfunctional theta phase coupling between hippocampus and medial prefrontal cortex (mPFC). We tested hypothesis by examining neural dynamics 18 participants with schizophrenia diagnosis, both medicated unmedicated; 26 age, sex IQ matched control subjects. All completed two tasks known to elicit hippocampal-prefrontal coupling: spatial memory task (during...

Altered neural dynamics in the medial prefrontal cortex (mPFC) and hippocampus may contribute to cognitive impairments complex chromosomal disorder Down syndrome (DS). Here, we demonstrate non-overlapping behavioral differences associated with distinct abnormalities hippocampal mPFC electrophysiology during a canonical spatial working memory task three partially trisomic mouse models of DS (Dp1Tyb, Dp10Yey, Dp17Yey) that together cover all regions homology human chromosome 21 (Hsa21). Dp1Tyb...

Successful navigation relies on reciprocal transformations between spatial representations in world-centered (allocentric) and self-centered (egocentric) frames of reference. The neural basis allocentric has been extensively investigated with grid, border, head-direction cells the medial entorhinal cortex (MEC) forming key components a 'cognitive map'. Recently, egocentric have also identified several brain regions, but evidence for coexistence neurons encoding variables each reference frame...

Abstract Neuroimaging studies have typically relied on rigorously controlled experimental paradigms to probe cognition, in which movement is restricted, primitive, an afterthought or merely used indicate a subject’s choice. Whilst powerful, these do not often resemble how we behave everyday life, so new generation of ecologically valid experiments are being developed. Magnetoencephalography (MEG) measures neural activity by sensing extracranial magnetic fields. It has recently been...

Most presynaptic terminals in the central nervous system are characterized by two functionally distinct vesicle populations: a recycling pool, which supports action potential-driven neurotransmitter release via exocytosis, and resting pool. The relative proportions of these pools highly variable between individual synapses, prompting speculation on their specific relationship, possible functions pool.Using fluorescence imaging FM-styryl dyes synaptophysinI-pHluorin(sypHy) as well correlative...

Hippocampal-medial prefrontal interactions are thought to play a crucial role in mental simulation. Notably, the frontal midline/medial pFC (mPFC) theta rhythm humans has been linked introspective and working memory. In parallel, rhythms have proposed coordinate processing medial temporal cortex, retrosplenial cortex (RSc), parietal during movement of viewpoint imagery, extending their association with physical rodent models. Here, we used noninvasive whole-head MEG investigate oscillatory...

The encoding of information in spike phase relative to local field potential (LFP) oscillations offers several theoretical advantages over equivalent firing rate codes. One notable example is provided by place and grid cells the rodent hippocampal formation, which exhibit precession-firing at progressively earlier phases 6-12 Hz movement-related theta rhythm as their spatial fields are traversed. It often assumed that such coding relies on a high amplitude baseline oscillation with...

Abstract Slow waves of neuronal activity are a fundamental component sleep that proposed to have homeostatic and restorative functions. Despite this, their interaction with pathology is unclear there only indirect evidence presence during wakefulness. Using intracortical recordings from the temporal lobe 25 patients epilepsy, we demonstrate existence local wake slow (LoWS) key features waves, including down-state firing. Consistent reduction in activity, LoWS were associated slowed cognitive...

Hippocampal place cells in freely moving rodents display both theta phase precession and procession, which is thought to play important roles cognition, but the neural mechanism for producing shift remains largely unknown. Here we show that firing rate adaptation within a continuous attractor network causes activity bump oscillate around external input, resembling sweeps of decoded position during locomotion. These forward backward naturally account procession individual neurons,...