A brain has distributed memory system, that is, each part of brain has several types of memories that work in somewhat different ways, to suit particular purposes. According to the stored time of contents memory can be divided into long term memory, short term memory and working memory. Research topics in memory exist coding, extract and retrieval of information. Current working memory attracts more researchers to involve.

Working memory will provides temporal space and enough information for complex tasks, such as understanding speech, learning, reasoning and attention. There are memory and reasoning functions in the working memory. It consists of three components: that is, central nervous performance system, video space primary processing and phonetic circuit.

Memory phenomena have also been categorized as explicit or implicit. Explicit memories involve the hippocampus-medial temporal lobe system. The most common current view of the memorial functions of the hippocampal system in declarative memory [5]. There are a lot of research issues which are waiting for us to resolve. What is the readout system from the hippocampal system to behavioural expression of learning in declarative memory? Where are the long-term declarative memories stored after the hippocampal system? What are the mechanisms of time-limited memory storage in hippocampus and storage of permanent memories in extra- hippocampal structures? Implicit memory involves the cerebellum, amygdala, and other systems. The cerebellum is necessary for classical conditioning of discrete behavioural responses under all condition. It is learning to make specific behavioural responses. The amygdalar system is learning fear and associated autonomic responses to deal with the situation.