Memory consolidation in the cerebellar cortex

Several forms of learning, including classical conditioning of the eyeblink, depend upon the cerebellum. In examining mechanisms of eyeblink conditioning in rabbits, reversible inactivations of the control circuitry have begun to dissociate aspects of cerebellar cortical and nuclear function in memory consolidation. It was previously shown that post-training cerebellar cortical, but not nuclear, inactivations with the GABA(A) agonist muscimol prevented consolidation but these findings left open the question as to how final memory storage was partitioned across cortical and nuclear levels. Memory consolidation might be essentially cortical and directly disturbed by actions of the muscimol, or it might be nuclear, and sensitive to the raised excitability of the nuclear neurons following the loss of cortical inhibition. To resolve this question, we simultaneously inactivated cerebellar cortical lobule HVI and the anterior interpositus nucleus of rabbits during the post-training period, so protecting the nuclei from disinhibitory effects of cortical inactivation. Consolidation was impaired by these simultaneous inactivations. Because direct application of muscimol to the nuclei alone has no impact upon consolidation, we can conclude that post-training, consolidation processes and memory storage for eyeblink conditioning have critical cerebellar cortical components. The findings are consistent with a recent model that suggests the distribution of learning-related plasticity across cortical and nuclear levels is task-dependent. There can be transfer to nuclear or brainstem levels for control of high-frequency responses but learning with lower frequency response components, such as in eyeblink conditioning, remains mainly dependent upon cortical memory storage

Analisis algoritma pencarian pada pohon-B

Pohon Telusur m-Cabang banyak diterapkan dalam external storage unfair iiialiage dgitct &lam jib-4A. -yang besar. Karerta alum kusatitat-3 etiperinkaa wain formasi potion variasi lairmya yang dapat menampung data dalam jumlah besar dan memiliki ketinggian minimum sedemikian sehingga data dapat dioperasikan dengan lebih effisien dan effektif Kriteria ini dipenuhi oleh Pohon-B. Dalam togas akhir ini, dijelaskan dua wacana panting dalam pembahasan Pohon-B, yaitu metode split yang diguuakan dalam proses penyisipan den consolidation dalam penghaptuum beserta anaiisis keduanya. Multiway (m-way ) search trees are mostly used, especially to store and to manage data on external storage in large quantities. For this quantity reason, it is necessary to examine another variety of tree formation which is able to accomodate data in large quantities with minimum height such that data can be operated and accessed more efficiently and more effectively. These criteria are fulfilled by B-trees In this final project, two main problems ( which are most discussed ) will be explained in discussing B-trees, that is, split method which is used in insertion process and consolidation method in deletion process with both analyses

Development and application of a novel cake strength tester

Caking can cause many problems in industries during processing or storage of particulate materials. Caking magnitude depends on several factors, for instance temperature, consolidation stress and storage time. In this research paper, a novel force displacement and easy-to-use caking tester for measuring quantitatively cake strength as a result of elevated temperature, consolidation stress and storage time is introduced. The developed tester outweighed the conventional uniaxial unconfined failure caking tester due to the defined location of the failure plane to maximise repeatability, the necessity for a lower quantity of powder, maximised exposed surface and lower wall friction as well as production costs. The experimental design has been conducted by changing the temperature, consolidation stress and storage duration. The results showed that the tester could distinguish cake strength between different experimental conditions. A statistical model has been successfully developed to study the effect of each variable on the cake strength

Dynamics of Hippocampal and Cortical Activation during Consolidation of a Nonspatial Memory

Observations of temporally graded retrograde amnesia after hippocampal damage suggest that the hippocampal region plays a critical, time-limited role in memory consolidation. However, these observations do not indicate where permanentmemory is stored, nor do they clarify whether the hippocampus normally remains involved in a nonessential way. Evidence from multiple neural imaging studies indicate the time-limited role of the hippocampus and suggest that the anterior cingulate cortex is a critical storage site of different types of long-term memory. However, each of the previous studies examined spatial memory, leaving open the question of whether different cortical areas support long-term memory for other types ofmaterial. We characterized the course of involvement of cortical and hippocampal areas in animals trained in an explicitlynonspatial task. First, we confirmed previous findings that hippocampal damage produces temporally graded retrogradeamnesia for the social transmission of a food preference (STFP) within our experimental protocol. Damage to thehippocampal region 1 d, but not 21 d, after training impaired subsequent recall of STFP. Then, we characterized theanatomical patterns of activation of the immediate early gene c-fos during retrieval of STFP immediately and 1, 2, and 21 dafter training. The ventral subiculum was activated during retrieval shortly after learning, but the level of activation declined at successive times. In contrast, olfactory recipient regions including piriform, entorhinal, and orbitofrontal cortex showed the opposite pattern, increasingly greater activation in successively later retrieval tests. These findings support the view that different cortical networks support long-term memory for different types of information

The Effects of Non-Contingent Extrinsic and Intrinsic Rewards on Memory Consolidation

Emotional and arousing treatments given shortly after learning enhance delayed memory retrieval in animal and human studies. Positive affect and reward induced prior to a variety of cognitive tasks enhance performance, but their ability to affect memory consolidation has not been investigated before. Therefore, we investigated the effects of a small, non-contingent, intrinsic or extrinsic reward on delayed memory retrieval. Participants (n = 108) studied and recalled a list of 30 affectively neutral, imageable nouns. Experimental groups were then given either an intrinsic reward (e.g., praise) or an extrinsic reward (e.g., $1). After a one-week delay, participants’ retrieval performance for the word list was significantly better in the extrinsic reward groups, whether the reward was expected or not, than in controls. Those who received the intrinsic reward performed somewhat better than controls, but the difference was not significant. Thus, at least some forms of arousal and reward, even when semantically unrelated to the learned material, can effectively modulate memory consolidation. These types of treatments might be useful for the development of new memory intervention strategies