Learning and memory are the main ways by which a living being adapts to changes and the uncertainty of the environment. An experience capable of producing changes in the nervous system and showing modifications in the behavior is considered as learning. Memory, a phenomenon usually inferred from those changes, makes us feel our lives are a continuum as time goes by (Morgado, I., 2011).
Learning produces morphological changes in dendritic spines, which could form the structural basis of memory. The mechanisms used are part of the basic structure of neurons. Serial triggers of different receptors promote morphological changes of the cytoskeleton, such changes are stabilized by the protein synthesis and the induction of new receptors on the membrane enabling the memory consolidation. Long-term memory is based on persistent structural changes (new dendritic spines). Short-term memory or retention of information for a short time is based on ephemeral, electrical or molecular changes in the neural networks involved. But if the changes persist as a result of the repetition of the experience, it can activate protein synthesis and make lasting structural changes (Morgado, I., 2011).
Implicit memory (MI), explicit memory (ME) and working memory (MT), three memory systems are distinguished. MI is also called procedural, it is information that allows us to perform motor and cognitive habits. It is gradually acquired and perfected with practice. It is usually faithful, rigid, durable and highly influenced by biological predisposition memory; this is the case of people with specific skills for a particular sport, acoustic or language skills. ME is the storage of facts (semantic memory) and events (episodic memory). MT is the conscious representation and temporal manipulation of the information necessary to perform complex cognitive operations, such as learning, language comprehension and reasoning (Morgado, I., 2011, psychobiology of learning and memory).