Emerging targets for the pharmacology of learning and memory
Section snippets
The various facets of memory
The majority of organisms exhibit cognitive functions that we identify as learning and memory. Studies of animal models and patients with circumscribed memory impairment have contributed to our understanding of cognitive processes, suggesting that memory is not a single entity, but there are different kinds of memory involving distinct neuronal systems in the brain [1]. The most persistent form of information storage is genetic, one that is constituted by innate, prefixed responses provided to
In search of a memory site
As mentioned, memory can be divided into various components and forms on the basis of the content (i.e. semantic or episodic), the type (i.e. associative), the level of processing (i.e. encoding, retrieval) and the duration (i.e. short-term and long-term) [11]. But how can we define learning and memory? Learning can be considered a process that allows us to acquire new information about the world and “which manifests itself by adaptative changes in individual behaviour as a result of
The role of the hippocampus in cognitive processes
Fundamental information on the role of a specific area of the brain in learning and memory derived from the most studied amnesic patient, H.M., who underwent bilateral removal of his medial temporal lobe that includes the hippocampus and the amygdala. The operation alleviated H.M.’s epilepsy, but also resulted in anterograde amnesia and partial loss of memory for events which occurred in the decade preceding the operation. Memory of more remote events was not affected; working memory did not
Learning and memory as multilevel phenomena: a foreshortening on cellular and molecular mechanisms of cognitive processes
In view of previous considerations, learning and memory can be analysed at different levels of biological organization. After a brief overview regarding the different forms of memory, and a few considerations on some circuits involved (in particular the hippocampus), the next part of this review will deal with some cellular and molecular levels of cognitive processes. Because learning and memory are dynamic processes, although not instantaneous changes, Burgoyne and Rose proposed that any cell,
New emerging targets for pharmacologic therapy of memory impairment
In this context, we will now consider some of the multiple possibilities of intervention to affect signal transduction cascades, with the aim to enlighten new pharmacological approaches to address memory deficits. In addition to a brief mention of glutamate, the review will be focused on some of the emerging extracellular and intracellular signals involved in memory trace formation such as angiotensin, carbonic anhydrase and APP. Attention will also be paid to the control of gene expression in
Conclusions
One of the most important efforts of the last decade in research is to gain a better insight on the mechanisms involved in cognitive function. Understanding the biochemical basis of learning and memory processes can certainly help to elucidate how to restore normal brain functioning. For years pharmacological research has been looking for novel routes and therapeutic approaches to address the problem of memory impairment. The biochemical entities participating in signal transduction cascades
Acknowledgements
The authors wish to thank Madelon Cook (Blanchette Rockefeller Neurosciences Institute, Rockville, MD, USA) for her help in carefully reviewing the text.
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