6 research outputs found
Recommended from our members
Reconsolidation-Extinction Interactions in Fear Memory Attenuation: The Role of Inter-Trial Interval Variability
Fear extinction typically results in the formation of a new inhibitory memory that
suppresses the original conditioned response. Evidence also suggests that extinction
training during a retrieval-induced labile period results in integration of the extinction
memory into the original fear memory, rendering the fear memory less susceptible to
reinstatement. Here we investigated the parameters by which the retrieval-extinction
paradigm was most effective in memory updating. Specifically, we manipulated the intertrial intervals (ITIs) between conditional stimulus (CS) presentations during extinction,
examining how having interval lengths with different degrees of variability affected the
strength of memory updating. We showed that randomizing the ITI of CS presentations
during extinction led to less return of fear via reinstatement than extinction with a fixed
ITI. Subjects who received variable ITIs during extinction also showed higher freezing
during the ITI, indicating that the randomization of CS presentations led to a higher
general reactivity during extinction, which may be one potential mechanism for memory
updating
Recommended from our members
Targeting mitochondria via methylene blue : implications in memory enhancement and neuroprotection
Memory—though seemingly simple in concept—is altogether a notoriously elusive and difficult process to understand. While some memories are fragile and changeable under certain circumstances, others are persistent and difficult to erase. This work is a comprehensive investigation into memories: how to change persistent ones, enhance complicated ones and protect delicate ones. The first objective of this work was to explore a strategy for manipulating fear memories, which are notoriously difficult to erase. This was done by testing different parameters for attenuation of fear using extinction as a strategy for interrupting fear memory reconsolidation. Briefly, by manipulating extinction parameters such that subjects were unable to predict the occurrence of fearful stimuli, we were able to maximize the degree of memory updating. Since memory processing is contingent upon specific neuronal activity, and neuronal activity is primarily fueled by products of mitochondrial respiration, the second and third objectives of this work focused largely on how manipulating mitochondrial activity enhances and protects memory processes respectively. This was done using mitochondrial enhancer methylene blue (USP grade). Methylene blue (MB) is a synthetic dye with a unique ability to cross the blood-brain barrier and diffuse into neuronal mitochondria. There, it serves as a redox electron cycler, increasing neurons’ capacity for mitochondrial respiration. The second objective of this work examined the effect of post-extinction administration of MB and its interaction with reconsolidation update mechanisms in the persistent attenuation of fear memories. Building on findings from the first objective, we found that administering MB after extinction helped subjects maintain the fear attenuation induced by extinction. The third objective explored the ability of MB to prevent the cognitive deficits arising from chronic cerebral hypoperfusion, a risk factor for mild cognitive impairment and Alzheimer’s disease. Finally, quantitative cytochrome oxidase histochemistry (a marker for mitochondrial activity) was used to map the effects of MB on brain mitochondria in the hypoperfusion model. Methylene blue attenuated some of the cognitive deficits that arose from chronic cerebral hypoperfusion, which was reflected in enhanced brain mitochondrial activity.Psycholog
A description of the ABCD organizational structure and communication framework
The Adolescent Brain Cognitive Development (ABCD) study is designed to be the largest study of brain development and child health in the United States, performing comprehensive assessments of 11,500 children repeatedly for 10 years. An endeavor of this magnitude requires an organized framework of governance and communication that promotes collaborative decision-making and dissemination of information. The ABCD consortium structure, built upon the Matrix Management approach of organizational theory, facilitates the integration of input from all institutions, numerous internal workgroups and committees, federal partners, and external advisory groups to make use of a broad range of expertise to ensure the study’s success. Keywords: Adolescence, Development, Neuroimaging, Longitudinal, Organizational framework, Governanc
A description of the ABCD organizational structure and communication framework.
The Adolescent Brain Cognitive Development (ABCD) study is designed to be the largest study of brain development and child health in the United States, performing comprehensive assessments of 11,500 children repeatedly for 10 years. An endeavor of this magnitude requires an organized framework of governance and communication that promotes collaborative decision-making and dissemination of information. The ABCD consortium structure, built upon the Matrix Management approach of organizational theory, facilitates the integration of input from all institutions, numerous internal workgroups and committees, federal partners, and external advisory groups to make use of a broad range of expertise to ensure the study's success