Learning And Memory example essay topic
After the surgery was performed, it was clear that H.M. had a profound loss of memory for new events following the removal of the hippocampus. Although H. M was able to remember events prior the surgery, he was unable to form new memories and take in new facts into long term memory. One interesting note was that although his declarative memory was severely impaired, his procedural memory remained intact. This was discovered through a series of tasks administered to HM. One task was a mirror drawing task and required HM to draw a picture of an object from its mirror image. It was found that HM showed improvement in his drawing skills upon doing the task over a period of time, although HM denied any recollection of ever having done the task before.
Moreover, HM was found to have a normal learning curve regarding the task, and retained his skills, regardless of his inability to remember the events. On another occasion, a psychologist had concealed a drawing pin in his hand and pricked HM as they shook hands. The following day, HM refused to shake the psychologist's hand, although he denied he ever saw the psychologist before. Such observations are consistent with the associations that the hippocampus is necessary to form declarative, episodic memory. The hippocampus is thought to be associated with short term memory and in consolidating which episodic acts will be stored as long term memories. Animal studies have shown that damage to the hippocampus hinders the learning process.
For example, rats with removed hippocampi were unable to remember where they had or had not been, and hence were effectively hindered from learning a new maze. Such observations suggest that the hippocampus is needed in learning contextual or spatial information. In another study, it was found that monkeys with hippocampus damage were unable to navigate though once familiar areas. And in yet another study with monkeys, it was observed that destroying the hippocampus and amygdala, destroyed previous learning and prevented new learning from taking place. From the observations with patients and animal studies alone, the important role of the hippocampus in memory and learning is quite obvious. However, the hippocampus is not the only area of the brain that accounts for the process of learning and memory storage as it seems that the hippocampus effects certain types of memory and learning more than others, such as declarive memory and spatial, contextual learning versus procedural tasks.
The interplays of the hippocampus to other parts of the brain is an important area of study of memory and learning and much is still to researched and consolidated on the subject.