scholarly journals Multiple memory formation in glassy landscapes

2021 ◽  
Vol 7 (33) ◽  
pp. eabg7133
Author(s):  
Chloe W. Lindeman ◽  
Sidney R. Nagel
Keyword(s):  
Periodic Orbits ◽  
Memory Formation ◽  
Identical Position ◽  
Sheared Suspensions ◽  
Insight Into ◽  
Simple Models

Cyclically sheared jammed packings form memories of the shear amplitude at which they were trained by falling into periodic orbits where each particle returns to the identical position in subsequent cycles. While simple models that treat clusters of rearranging particles as isolated two-state systems offer insight into this memory formation, they fail to account for the long training times and multiperiod orbits observed in simulated sheared packings. We show that adding interactions between rearranging clusters overcomes these deficiencies. In addition, interactions allow simultaneous encoding of multiple memories, which would not have been possible otherwise. These memories are different in an essential way from those found in other systems, such as multiple transient memories observed in sheared suspensions, and contain information about the strength of the interactions.

Nitric Oxide Signals That Aplysia Have Attempted to Eat, a Necessary Component of Memory Formation After Learning That Food Is Inedible

2006 ◽  
Vol 96 (3) ◽  
pp. 1247-1257 ◽  
Author(s):  
Ayelet Katzoff ◽  
Tziona Ben-Gedalya ◽  
Itay Hurwitz ◽  
Nimrod Miller ◽  
Yehoshua Z. Susswein ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Methylene Blue ◽  
Rejection Rate ◽  
Memory Formation ◽  
Critical Component ◽  
No Donor ◽  
Ad Libitum ◽  
Ad Libitum Feeding ◽  
Insight Into ◽  
Stimulation Of

Inhibiting nitric oxide (NO) synthesis during learning that food is inedible in Aplysia blocks subsequent memory formation. To gain insight into the function of NO transmission during learning we tested whether blocking NO synthesis affects aspects of feeding that are expressed both in a nonlearning context and during learning. Inhibiting NO synthesis with L-NAME and blocking guanylyl cyclase with methylene blue decreased the efficacy of ad libitum feeding. D-NAME had no effect. L-NAME also decreased rejection responses frequency, but did not affect rejection amplitude. The effect of L-NAME was explained by a decreased signaling that efforts to swallow are not successful, leading to a decreased rejection rate, and a decreased ability to reposition and subsequently consume food in ad libitum feeding. Signaling that animals have made an effort to swallow is a critical component of learning that food is inedible. Stimulation of the lips with food alone did not produce memory, but stimulation combined with the NO donor SNAP did produce memory. Exogenous NO at a concentration causing memory also excited a key neuron responding to NO, the MCC. Block of the cGMP second-messenger cascade during training by methylene blue also blocked memory formation after learning. Our data indicate that memory arises from the contingency of three events during learning that food is inedible. One of the events is efforts to swallow, which are signaled by NO by cGMP.

scholarly journals A Bifurcation Analysis and Sensitivity Study of Brake Creep Groan

2021 ◽  
Vol 31 (16) ◽  
Author(s):  
Shaun Smith ◽  
James Knowles ◽  
Byron Mason ◽  
Sean Biggs
Keyword(s):  
Periodic Orbits ◽  
Degrees Of Freedom ◽  
Initial Conditions ◽  
Period Doubling ◽  
Nonlinear Behavior ◽  
Sensitivity Study ◽  
Friction Model ◽  
Model Parameters ◽  
Period Doubling Bifurcations ◽  
Simple Models

Creep groan is the undesirable vibration observed in the brake pad and disc as brakes are applied during low-speed driving. The presence of friction leads to nonlinear behavior even in simple models of this phenomenon. This paper uses tools from bifurcation theory to investigate creep groan behavior in a nonlinear 3-degrees-of-freedom mathematical model. Three areas of operational interest are identified, replicating results from previous studies: region 1 contains repelling equilibria and attracting periodic orbits (creep groan); region 2 contains both attracting equilibria and periodic orbits (creep groan and no creep groan, depending on initial conditions); region 3 contains attracting equilibria (no creep groan). The influence of several friction model parameters on these regions is presented, which identify that the transition between static and dynamic friction regimes has a large influence on the existence of creep groan. Additional investigations discover the presence of several bifurcations previously unknown to exist in this model, including Hopf, torus and period-doubling bifurcations. This insight provides valuable novel information about the nature of creep groan and indicates that complex behavior can be discovered and explored in relatively simple models.

scholarly journals Perceptual Boundaries Cause Mnemonic Trade-Offs Between Local Boundary Processing and Across-Trial Associative Binding

2017 ◽  
Author(s):  
Andrew C. Heusser ◽  
Youssef Ezzyat ◽  
Ilana Shiff ◽  
Lila Davachi
Keyword(s):  
Temporal Order ◽  
Memory Formation ◽  
Organizational Processes ◽  
Trade Off ◽  
Local Boundary ◽  
Trade Offs ◽  
Behavioral Studies ◽  
Temporal Order Memory ◽  
Episodic Memories ◽  
Insight Into

Episodic memories are not veridical records of our lives, but rather are better described as organizedsummaries of experience. Theories and empirical research suggest that shifts in perceptual, temporal, andsemantic information lead to a chunking of our continuous experiences into segments, or “events.”However, the consequences of these contextual shifts on memory formation and organization remainsunclear. In a series of 3 behavioral studies, we introduced context shifts (or “event boundaries”) betweentrains of stimuli and then examined the influence of the boundaries on several measures of associativememory. In Experiment 1, we found that perceptual event boundaries strengthened associative bindingof item-context pairings present at event boundaries. In Experiment 2, we observed reduced temporalorder memory for items encoded in distinct events relative to items encoded within the same event, anda trade-off between the speed of processing at boundaries, and temporal order memory for items thatflanked those boundaries. Finally, in Experiment 3 we found that event organization imprinted structureon the order in which items were freely recalled. These results provide insight into how boundary- andevent-related organizational processes during encoding shape subsequent representations of events inepisodic memory.

scholarly journals Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning

2021 ◽  
Author(s):  
Haneen Kayyal ◽  
Sailendrakumar Kolatt Chandran ◽  
Adonis Yiannakas ◽  
Nathaniel Gould ◽  
Mohammad Khamaisy ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Sensory Information ◽  
Insular Cortex ◽  
Memory Formation ◽  
Intrinsic Properties ◽  
Insight Into ◽  
Taste Experience ◽  
Neophobic Response

To survive in an ever-changing environment, animals must detect and learn salient information. The anterior insular cortex (aIC) and medial prefrontal cortex (mPFC) are heavily implicated in salience and novelty processing, and specifically, the processing of taste sensory information. Here, we examined the role of aIC-mPFC reciprocal connectivity in novel taste neophobia and memory formation, in mice. Using pERK and neuronal intrinsic properties as markers for neuronal activation, and retrograde AAV (rAAV) constructs for connectivity, we demonstrate a correlation between aIC-mPFC activity and novel taste experience. Furthermore, by expressing inhibitory chemogenetic receptors in these projections, we show that aIC-to-mPFC activity is necessary for both taste neophobia and its attenuation. However, activity within mPFC-to-aIC projections is essential only for the neophobic reaction but not for the learning process. These results provide an insight into the cortical circuitry needed to detect, react to- and learn salient stimuli, a process critically involved in psychiatric disorders.

Spatiotemporal Distributions of Unstable Periodic Orbits in Noisy Coupled Chaotic Systems

2003 ◽  
Vol 13 (09) ◽  
pp. 2673-2680
Author(s):  
Kevin Dolan ◽  
Annette Witt ◽  
Jürgen Kurths ◽  
Frank Moss
Keyword(s):  
Periodic Orbits ◽  
Unstable Periodic Orbits ◽  
Coupling Structure ◽  
Spatially Extended ◽  
Experimental Time Series ◽  
Linear Correlation Analysis ◽  
Spatially Extended Systems ◽  
Recurrence Method ◽  
Dynamical Information ◽  
Insight Into

Techniques for detecting encounters with unstable periodic orbits (UPOs) have been very successful in the analysis of noisy, experimental time series. We present here a technique for applying the topological recurrence method of UPO detection to spatially extended systems. This approach is tested on a network of diffusively coupled chaotic Rössler systems, with both symmetric and asymmetric coupling schemes. We demonstrate how to extract encounters with UPOs from such data, and present a preliminary method for analyzing the results and extracting dynamical information from the data, based on a linear correlation analysis of the spatiotemporal occurrence of encounters with these low period UPOs. This analysis can provide an insight into the coupling structure of such a spatially extended system.

scholarly journals Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Haneen Kayyal ◽  
Sailendrakumar Kolatt Chandran ◽  
Adonis Yiannakas ◽  
Nathaniel Gould ◽  
Mohammad Khamaisy ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Sensory Information ◽  
Insular Cortex ◽  
Memory Formation ◽  
Intrinsic Properties ◽  
Insight Into ◽  
Taste Experience ◽  
Neophobic Response

To survive in an ever-changing environment, animals must detect and learn salient information. The anterior insular cortex (aIC) and medial prefrontal cortex (mPFC) are heavily implicated in salience and novelty processing, and specifically, the processing of taste sensory information. Here, we examined the role of aIC-mPFC reciprocal connectivity in novel taste neophobia and memory formation, in mice. Using pERK and neuronal intrinsic properties as markers for neuronal activation, and retrograde AAV (rAAV) constructs for connectivity, we demonstrate a correlation between aIC-mPFC activity and novel taste experience. Furthermore, by expressing inhibitory chemogenetic receptors in these projections, we show that aIC-to-mPFC activity is necessary for both taste neophobia and its attenuation. However, activity within mPFC-to-aIC projections is essential only for the neophobic reaction but not for the learning process. These results provide an insight into the cortical circuitry needed to detect, react to- and learn salient stimuli, a process critically involved in psychiatric disorders.

scholarly journals Differential regulation of native and learned behavior by creb-1/crh-1 in Caenorhabditis elegans

2019 ◽  
Author(s):  
Yogesh Dahiya ◽  
Saloni Rose ◽  
Shruti Thapliyal ◽  
Shivam Bhardwaj ◽  
Maruthi Prasad ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Memory Formation ◽  
Long Term Memory ◽  
Null Mutant ◽  
Term Memory ◽  
Learned Behavior ◽  
C Elegans ◽  
Insight Into ◽  
Null Mutants

1.AbstractMemory formation is crucial for the survival of animals. Here, we study the effect of different crh-1 (C. elegans homolog of mammalian CREB1) mutations on the ability of C. elegans to form long-term memory (LTM). Null mutants in creb1/crh-1 are defective in LTM formation across phyla. We show that specific isoforms of CREB1/CRH-1, CRH-1c and CRH-1e, are primarily responsible for memory related functions of the transcription factor in C. elegans. Silencing of CRH-1e expressing neurons during training for LTM formation abolishes the long-term memory of the animal. Further, CRH-1e expression in RIM or AVE neurons is sufficient to rescue long-term memory defects of creb1/crh-1 null mutants. We show that apart from being LTM defective, creb1/crh-1 null mutant animals show defects in native chemotaxis behavior. We characterize the amino acids K247 and K266 as responsible for the LTM related functions of CRH-1 while being dispensable for it’s native chemotaxis behavior. These findings provide insight into the spatial and temporal workings of a crucial transcription factor and can be further exploited to find CREB1 targets involved in the process of memory formation.

scholarly journals Identical Shapes Results in a Failed Memory Formation of Location of Dark Surroundings in Planarians

2021 ◽  
Author(s):  
Kaiyuan Huang ◽  
Yufei Liu ◽  
Yixi Duan ◽  
Kehan Chen ◽  
Ziyun Xiao ◽  
...  
Keyword(s):  
3D Printing ◽  
Spatial Learning ◽  
Brain Structure ◽  
Memory Formation ◽  
Training Method ◽  
Learning Paradigm ◽  
Printing Techniques ◽  
Insight Into

Abstract Planarians, the first kind of animal to have evolved a brain structure1 yet has not evolved visual sense, was demonstrated to have a capability of spatial learning in the last several decades2, but what does the navigation of planarians depends on is still unknown. Here, we provide an objective, strictly variable-controlled planarian training method using 3D printing techniques3 fabricated mazes. Then we use modifications of the mazes to first demonstrate a learning paradigm that worms can memorize the location of a darkened surrounding through training. However, a memory formation failure was found that in the situation of providing identical shapes in a maze, planarians cannot memorize the location of the darkened surrounding. Thus, this result shows the planarians associated darkness with the crude shape of the objects they have crawled on, which is a kind of spatial learning. This finding provides not only a key insight into spatial learning information that planarians are processing but also an interpretation of the origin of memory formation where higher grades of memory formation might originate from.

Calibration problems in hydrogen luminosities

1966 ◽  
Vol 24 ◽  
pp. 322-330
Author(s):  
A. Beer
Keyword(s):  
Galactic Structure ◽  
B Stars ◽  
Insight Into

The investigations which I should like to summarize in this paper concern recent photo-electric luminosity determinations of O and B stars. Their final aim has been the derivation of new stellar distances, and some insight into certain patterns of galactic structure.

Stochasting modeling of planetary ring systems

1984 ◽  
Vol 75 ◽  
pp. 461-469 ◽  
Author(s):  
Robert W. Hart
Keyword(s):  
Maximum Entropy ◽  
Ring System ◽  
The Sun ◽  
Ultimate State ◽  
Interparticle Interactions ◽  
Ring Systems ◽  
First Order ◽  
Planetary Ring ◽  
Insight Into

ABSTRACTThis paper models maximum entropy configurations of idealized gravitational ring systems. Such configurations are of interest because systems generally evolve toward an ultimate state of maximum randomness. For simplicity, attention is confined to ultimate states for which interparticle interactions are no longer of first order importance. The planets, in their orbits about the sun, are one example of such a ring system. The extent to which the present approximation yields insight into ring systems such as Saturn's is explored briefly.

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