At the beginning of the 20^(th)century,German scientist Richard Semon introduced the term'engram'to describe the neural substrate implicated in the processes of memory formation and retrieval[1].The trace of t...At the beginning of the 20^(th)century,German scientist Richard Semon introduced the term'engram'to describe the neural substrate implicated in the processes of memory formation and retrieval[1].The trace of the corresponding biophysical and biochemical changes in the brain responding to an external stimulus is called an engram,and understanding the physical manifestations of memory formation and recall remains a fundamental yet unresolved question[2].展开更多
Post-traumatic stress disorder(PTSD)is a psychiatric disorder caused by traumatic past experiences,rooted in the neurocircuits of fear memory formation.Memory processes include encoding,storing,and recalling to forget...Post-traumatic stress disorder(PTSD)is a psychiatric disorder caused by traumatic past experiences,rooted in the neurocircuits of fear memory formation.Memory processes include encoding,storing,and recalling to forgetting,suggesting the potential to erase fear memories through timely interventions.Conventional strategies such as medications or electroconvulsive therapy often fail to provide permanent relief and come with significant side-effects.This review explores how fear memory may be erased,particularly focusing on the mnemonic phases of reconsolidation and extinction.Reconsolidation strengthens memory,while extinction weakens it.Interfering with memory reconsolidation could diminish the fear response.Alternatively,the extinction of acquired memory could reduce the fear memory response.This review summarizes experimental animal models of PTSD,examines the nature and epidemiology of reconsolidation to extinction,and discusses current behavioral therapy aimed at transforming fear memories to treat PTSD.In sum,understanding how fear memory updates holds significant promise for PTSD treatment.展开更多
While a hippocampal–cortical dialogue is generally thought to mediate memory consolidation,which is crucial for engram function,how it works remains largely unknown.Here,we examined the interplay of neural signals fr...While a hippocampal–cortical dialogue is generally thought to mediate memory consolidation,which is crucial for engram function,how it works remains largely unknown.Here,we examined the interplay of neural signals from the retrosplenial cortex(RSC),a neocortical region,and from the hippocampus in memory consolidation by simultaneously recording sharp-wave ripples(SWRs)of dorsal hippocampal CA1 and neural signals of RSC in free-moving mice during the delayed spatial alternation task(DSAT)and subsequent sleep.Hippocampal–RSC coordination during SWRs was identified in nonrapid eye movement(NREM)sleep,reflecting neural reactivation of decision-making in the task,as shown by a peak reactivation strength within SWRs.Using modified generalized linear models(GLMs),we traced information flow through the RSC–CA1–RSC circuit around SWRs during sleep following DSAT.Our findings show that after spatial training,RSC excitatory neurons typically increase CA1 activity prior to hippocampal SWRs,potentially initiating hippocampal memory replay,while inhibitory neurons are activated by hippocampal outputs in post-SWRs.We further identified certain excitatory neurons in the RSC that encoded spatial information related to the DSAT.These neurons,classified as splitters and location-related cells,showed varied responses to hippocampal SWRs.Overall,our study highlights the complex dynamics between the RSC and hippocampal CA1 region during SWRs in NREM sleep,underscoring their critical interplay in spatial memory consolidation.展开更多
文摘At the beginning of the 20^(th)century,German scientist Richard Semon introduced the term'engram'to describe the neural substrate implicated in the processes of memory formation and retrieval[1].The trace of the corresponding biophysical and biochemical changes in the brain responding to an external stimulus is called an engram,and understanding the physical manifestations of memory formation and recall remains a fundamental yet unresolved question[2].
基金supported by the National Key Research and Development Project of China(2021ZD0202800)the National Natural Science Foundation of China(U21A20418,82003727).
文摘Post-traumatic stress disorder(PTSD)is a psychiatric disorder caused by traumatic past experiences,rooted in the neurocircuits of fear memory formation.Memory processes include encoding,storing,and recalling to forgetting,suggesting the potential to erase fear memories through timely interventions.Conventional strategies such as medications or electroconvulsive therapy often fail to provide permanent relief and come with significant side-effects.This review explores how fear memory may be erased,particularly focusing on the mnemonic phases of reconsolidation and extinction.Reconsolidation strengthens memory,while extinction weakens it.Interfering with memory reconsolidation could diminish the fear response.Alternatively,the extinction of acquired memory could reduce the fear memory response.This review summarizes experimental animal models of PTSD,examines the nature and epidemiology of reconsolidation to extinction,and discusses current behavioral therapy aimed at transforming fear memories to treat PTSD.In sum,understanding how fear memory updates holds significant promise for PTSD treatment.
基金the Shuimu Tsinghua Scholar ProgramProject funded by National Natural Science Foundation of China(62125106,61860206003,and 62088102)+4 种基金in part by Shenzhen Science and Technology Research and Development Funds(JCYJ20180507183706645)in part by Ministry of Science and Technology of China(2021ZD0109901)in part by Beijing National Research Center for Information Science and Technology(BNR2020RC01002)China Postdoctoral Science Foundation(2020TQ0172,2020M670338,and YJ20200109)Postdoctoral International Exchange Program(YJ20210124)。
基金supported by the National Key R&D Program of China(2019YFA0709504 and 2021ZD0202805)the National Natural Science Foundation of China(32471083,82271292,and 31900719)+2 种基金the Innovative Research Team of High-level Local Universities in Shanghai,111 Project(B18015)Shanghai Municipal Science and Technology Major Project(2018SHZDZX01)Shanghai Center for Brain Science and Brain-Inspired Technology.
文摘While a hippocampal–cortical dialogue is generally thought to mediate memory consolidation,which is crucial for engram function,how it works remains largely unknown.Here,we examined the interplay of neural signals from the retrosplenial cortex(RSC),a neocortical region,and from the hippocampus in memory consolidation by simultaneously recording sharp-wave ripples(SWRs)of dorsal hippocampal CA1 and neural signals of RSC in free-moving mice during the delayed spatial alternation task(DSAT)and subsequent sleep.Hippocampal–RSC coordination during SWRs was identified in nonrapid eye movement(NREM)sleep,reflecting neural reactivation of decision-making in the task,as shown by a peak reactivation strength within SWRs.Using modified generalized linear models(GLMs),we traced information flow through the RSC–CA1–RSC circuit around SWRs during sleep following DSAT.Our findings show that after spatial training,RSC excitatory neurons typically increase CA1 activity prior to hippocampal SWRs,potentially initiating hippocampal memory replay,while inhibitory neurons are activated by hippocampal outputs in post-SWRs.We further identified certain excitatory neurons in the RSC that encoded spatial information related to the DSAT.These neurons,classified as splitters and location-related cells,showed varied responses to hippocampal SWRs.Overall,our study highlights the complex dynamics between the RSC and hippocampal CA1 region during SWRs in NREM sleep,underscoring their critical interplay in spatial memory consolidation.
