The Encoding of Contextual Fear Conditioning - 1296 Words

The formation of new memories requires protein synthesis dependent changes in synaptic structure and plasticity in the hippocampus. Studies in humans and animals suggest that these memories are initially stored in hippocampus but later transferred to cortex for permanent storage. This phenomenon is described as systems consolidation of memories. While the specific role for new protein synthesis in hippocampus in early encoding of memories is established, whether protein synthesis in medial prefrontal cortex play a major role in encoding of memories is unclear. To address this question, we used contextual fear conditioning (CFC) of mouse, a behavior training that induce long lasting memories. A single training session produces robust lifelong memory (8) that can be measured using automated procedures (9). Several studies have used CFC training as a model to study hippocampal-cortical communications and mechanisms underlying systems consolidation of memories. Contextual fear memories a re initially stored in hippocampus and then moved to medial prefrontal cortex (mPFC) for long-term storage. We assume that if encoding of contextual fear memories require protein synthesis at both hippocampus and PFC, we will be able to identify translationally active mRNAs in hippocampus and PFC. Because RNAs associated with polyribosomes indicate translational activation, we first isolated polyribosomes from mPFC and hippocampus at two time points (one hour and six hours, hereafter T1 and T2Show MoreRelatedThe Effect Of New Protein Synthesis At Prl Cortex900 Words   |  4 Pages training. Mice infused with anisomycin (n= 12) immediately after conditioning showed impairment in contextual fear memory compared with vehicle-infused animals (saline, n=18) when tested 24 hours after CFC training (DF=28, F=7.19, t-test: p 0.05) (Figure 2A). Surprisingly, irrespective of the overall decrease in freezing percentage, mice injected with anisomycin did not show any statistical difference in the level of freezing within the first 2 minutes of the test (Figure 2B). By the thirdRead MoreAging And Young Blood944 Words   |  4 Pagesset up two cognitive testings, contextual fear conditioning and radial arm water maze (RAWM). The unpaired aged mice are divided into two groups, with one group injected with young plasma and the other injected with aged plasma before the testings. The two groups show no significantly different performance during the training phases of the two testings. Nevertheless, during the testing phases, the mice rejected with young plasma show improved freezing in contextual memory testing and better performanceRead MoreEssay On Aging1000 Words   |  4 Pagescapable to potentiate synaptic plasticity in aged mice. 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For behaviorism, learning is the acquisition of new behavior through conditioning. There are two types of possible conditioning: 1)  Classical conditioning, where the behavior becomes a reflex response to stimulus as in the case of  Pavlovs Dogs. Pavlov was interested in studying reflexes, when he saw that the dogs drooled without the proper stimulus. Although noRead MoreOcd - Symptoms, Causes, Treatment131367 Words   |  526 Pagesemotion of fear, is a universal human experience that plays a central role in human adaptation and survival. The basic function of fear is to signal a threat or impending danger (Barlow, 2002). The feeling of anxiousness associated with making a speech before 3 4 THE NATURE OF OCD a large audience or going for a job interview is understandable, given the potential for embarrassment or rejection. Even some of the phobias that are well known to clinicians, such as acrophobia (fear of heights)