Learning and Memory Essay -- Biology Essays Research Papers

Learning and Memory Learning and memory are not unitary processes. Learning is the process by which new information is acquired; memory is the process by which that knowledge is retained. Learning can be divided into two types: 1)Explicit memory is the conscious acquisition of knowledge about people, places and things. It occurs in the highly developed vertebrate brain ,mainly in the diencephalic structure (1). 2) Implicit memory is the non conscious learning of motor skills and other tasks. It does not depend on the temporal lobe, but involves the sensory, motor associated pathways in the expression of learning process. This type of memory can be studied in higher invertebrates whereas explicit learning is only studied in mammals (2). After reviewing the enormous amount of information pertaining to memory and learning, I decided to focus on two areas of interest: the actual mechanism of learning and the process of consolidation which relates to how something that is learned is then stored as memory. The first area of interest involving learning has been elucidated by the concept of long term potentiation (LTP) in mammals and vertebrates and the second related area of consolidation has been elucidated by an invertebrate model of Aplysia. Long term potentiation can be defined as a long lasting increase in synaptic effectiveness which follows from high frequency of stimulation of afferent fibers. Although LTP occurs throughout the nervous system, it's focus has mainly been in the hippocampus which is involved in the formation of certain memories (1). Furthermore, LTP has been found to occur in not only the mammalian brain but also in other vertebrates such as the goldfish, bullfrog, bird and lizard. Characteristics of L... ...ns needed for growth. This shows that long term changes in both mammals and Aplysia are linked to gene induction which leads to synaptic growth (3,4). In conclusion, the structural changes implicated in long term memory are due to new protein and mRNA synthesis. These changes in transcription and translation can be initiated by repeated exposure to modulatory transmitters (5 HT) which mimic the effects of hormones and growth factors. Furthermore, through second messenger systems that regulate gene expression, modulatory transmitters utilized for learning can initiate synaptic growth. Internet Sources: http://oac.hsc.uth.tmc.edu/apstracts/1995/jn/April/8n.html http://oac.hsc.uth.tmc.edu/apstracts/1997/jn/December/353N.html http://oac.hsc.uth.tmc.edu/apstracts/1997/jn/February/45n.html http://oac.hsc.uth.tmc.edu/apstracts/1997/jn/December/320N.html