scholarly journals Regulation of memory storage through epigenetic alterations: a new role for RNA

2018 ◽  
Vol 40 (5) ◽  
pp. 12-15
Author(s):  
Alexis Bédécarrats ◽  
David L. Glanzman
Keyword(s):  
Synaptic Plasticity ◽  
Significant Loss ◽  
Memory Storage ◽  
Long Term Memory ◽  
Plasticity Model ◽  
Epigenetic Alterations ◽  
Physical Changes ◽  
Ramón Y Cajal

A fundamental assumption in modern psychology and neuroscience is that memory is stored as physical changes in the brain. More than a century ago, the famous neuroanatomist Ramón Y Cajal (see the article entitled “Santiago Ramón y Cajal, the ultimate scientist?” in this issue of The Biochemist) postulated that changes in the strength of synaptic connections between neurons were the physical substrate for memory. Extensive experimental evidence has since established the dominance of this connectionist view, referred to as the “synaptic plasticity” model. However, although the synaptic plasticity model broadly accords with the results of neurobiological studies of learning and memory, it does not fully account for the extraordinary resilience of memory despite the significant loss of synapses during such phenomena as development, trauma and ageing. Here, we will focus on the newly discovered role of small non-coding RNAs (ncRNAs) as potential master regulators of learning-induced epigenesis, neuronal plasticity and, ultimately, memory. In support of this idea, recent data from our lab indicate that RNA can promote the transfer of long-term memory from a trained to an untrained (naïve) animal.

Role of atypical protein kinases in maintenance of long-term memory and synaptic plasticity

2017 ◽  
Vol 82 (3) ◽  
pp. 243-256 ◽  
Author(s):  
A. A. Borodinova ◽  
A. B. Zuzina ◽  
P. M. Balaban
Keyword(s):  
Synaptic Plasticity ◽  
Protein Kinases ◽  
Long Term Memory ◽  
Term Memory

scholarly journals Reading Memory Formation from the Eyes

2018 ◽  
Author(s):  
Anne Bergt ◽  
Anne E. Urai ◽  
Tobias H. Donner ◽  
Lars Schwabe
Keyword(s):  
Synaptic Plasticity ◽  
Memory Formation ◽  
Pupil Dilation ◽  
Long Term Memory ◽  
Term Memory ◽  
Pupil Response ◽  
Rapid Formation ◽  
The Brain

At any time, we are processing thousands of stimuli, but only few of them will be remembered hours or days later. Is there any way to predict which ones? Here, we show that the pupil response to ongoing stimuli, an indicator of physiological arousal, is a reliable predictor of long-term memory for these stimuli, over at least one day. Pupil dilation was tracked while participants performed visual and auditory encoding tasks. Memory was tested immediately after encoding and 24 hours later. Irrespective of the encoding modality, trial-by-trial variations in pupil dilation predicted which stimuli were recalled in the immediate and 24 hours-delayed tests. These results show that our eyes may provide a window into the formation of long-term memories. Furthermore, our findings underline the important role of central arousal systems in the rapid formation of memories in the brain, possibly by gating synaptic plasticity mechanisms.

scholarly journals Dynamic Integrative Synaptic Plasticity Explains the Spacing Effect in the Transition from Short- to Long-Term Memory

2019 ◽  
Vol 31 (11) ◽  
pp. 2212-2251 ◽  
Author(s):  
Terry Elliott
Keyword(s):  
Synaptic Plasticity ◽  
Mapk Pathway ◽  
Spacing Effect ◽  
Long Term Memory ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Term Memory ◽  
Low Pass

Repeated stimuli that are spaced apart in time promote the transition from short- to long-term memory, while massing repetitions together does not. Previously, we showed that a model of integrative synaptic plasticity, in which plasticity induction signals are integrated by a low-pass filter before plasticity is expressed, gives rise to a natural timescale at which to repeat stimuli, hinting at a partial account of this spacing effect. The account was only partial because the important role of neuromodulation was not considered. We now show that by extending the model to allow dynamic integrative synaptic plasticity, the model permits synapses to robustly discriminate between spaced and massed repetition protocols, suppressing the response to massed stimuli while maintaining that to spaced stimuli. This is achieved by dynamically coupling the filter decay rate to neuromodulatory signaling in a very simple model of the signaling cascades downstream from cAMP production. In particular, the model's parameters may be interpreted as corresponding to the duration and amplitude of the waves of activity in the MAPK pathway. We identify choices of parameters and repetition times for stimuli in this model that optimize the ability of synapses to discriminate between spaced and massed repetition protocols. The model is very robust to reasonable changes around these optimal parameters and times, but for large changes in parameters, the model predicts that massed and spaced stimuli cannot be distinguished or that the responses to both patterns are suppressed. A model of dynamic integrative synaptic plasticity therefore explains the spacing effect under normal conditions and also predicts its breakdown under abnormal conditions.

scholarly journals The Medial Prefrontal Cortex and Fear Memory: Dynamics, Connectivity, and Engrams

2021 ◽  
Vol 22 (22) ◽  
pp. 12113
Author(s):  
Lucie Dixsaut ◽  
Johannes Gräff
Keyword(s):  
Prefrontal Cortex ◽  
Medial Prefrontal Cortex ◽  
Memory Formation ◽  
Memory Storage ◽  
Long Term Memory ◽  
Brain Areas ◽  
Long Term Storage ◽  
And Storage

It is becoming increasingly apparent that long-term memory formation relies on a distributed network of brain areas. While the hippocampus has been at the center of attention for decades, it is now clear that other regions, in particular the medial prefrontal cortex (mPFC), are taking an active part as well. Recent evidence suggests that the mPFC—traditionally implicated in the long-term storage of memories—is already critical for the early phases of memory formation such as encoding. In this review, we summarize these findings, relate them to the functional importance of the mPFC connectivity, and discuss the role of the mPFC during memory consolidation with respect to the different theories of memory storage. Owing to its high functional connectivity to other brain areas subserving memory formation and storage, the mPFC emerges as a central hub across the lifetime of a memory, although much still remains to be discovered.

Genetic Approaches to the Study of Synaptic Plasticity and Memory Storage

CNS Spectrums ◽  
2003 ◽  
Vol 8 (8) ◽  
pp. 597-610 ◽  
Author(s):  
Ted Abel ◽  
Michael P. Kaplan
Keyword(s):  
Synaptic Plasticity ◽  
Molecular Mechanisms ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Memory Storage ◽  
Long Term Memory ◽  
Protein Signaling ◽  
Term Memory ◽  
Element Binding Protein

ABSTRACTLong-term memory is believed to depend on long-lasting changes in the strength of synaptic transmission known as synaptic plasticity. Understanding the molecular mechanisms of long-term synaptic plasticity is one of the principle goals of neuroscience. Among the most powerful tools being brought to bear on this question are genetically modified mice with changes in the expression or biological activity of genes thought to contribute to these processes. This article reviews how strains of mice with alterations in the cyclic adenosine monophosphate/protein kinase A/cyclic adenosine monophosphate-response element-binding protein signaling pathway have advanced our understanding of the biological basis of learning and memory.

Sign in / Sign up

Export Citation Format

Share Document