Various clinical and psychological studies have shown that the hippocampus in the medial temporal lobe is responsible for important learning and memory. In the majority of studies, many researchers propose that the hippocampus is responsible for long-term memory (LTM). LTM impairments occur when damages to bilateral hippocampi are present and can result in anterograde amnesia (difficulty in forming recent memories), retrograde amnesia (difficulty in retrieving memories from the past), or both. However, in this paper, the relationship between the hippocampus and fear memory will be explored explicitly.
Understanding the reasoning behind amnesia and the hippocampus is of critical importance in neuroscience. Discussed by Cipolotti & Bird (2006), LTM impairments can lead to anterograde and retrograde amnesia if the medial temporal lobe (MTL) is damaged bilaterally. Specifically, the two most important types of LTM related to anterograde and retrograde amnesia are episodic and semantic memories. Conversely, many researchers have long debated the true functions of the hippocampus and have allowed two theories to emerge. The standard model of consolidation (SMC) assumes that the hippocampus is important in consolidating LTM, while the multiple trace theory (MTT) argues that information is encoded by specific memory traces by the hippocampus. These two theories help further explain the vast functions of the hippocampus. However, in regards to amnesic patients, the SMC has proven to be more widely accepted due to reported results implying that the hippocampus is important in consolidating LTM. In contrast, in anterograde patients, memories can be retrieved through recollection and familiarity. In fact, it has been proposed that the recol...
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...eezing in mice that were previously fear conditioned in a different setting, which suggests that light-induced fear memory recall is setting specific. What this suggests is that activating a population of hippocampus neurons that may have previously had memory traces stored, is enough for a memory to be recalled (Liu et al, 2012). The development of optogenetics has provided great insight in fear memory recall, nevertheless, more research into further testing if different types of memories can be recalled through optogenetics. By exploring this possibility, this may help amnesic patients in recalling lost memories.
The function of the hippocampus is crucial for LTM consolidation and with recollection and familiarity, however recent research in mice and recent development in optogenetics has enhanced a new understanding between hippocampus and fear memory recall.
“At the University of California at Irvine, experiments in rats indicate that the brain’s hormonal reaction to fear can be inhibited, softening the formation of memories and the emotions they evoke” (Baard).
Hippocampus is a small, curved region, which exists in both hemispheres of the brain and plays a vital role in emotions, learning and acquisition of new information. It also contributes majorly to long term memory, which is permanent information stored in the brain. Although long term memory is the last information that can be forgotten, its impairment has become very common nowadays. The dysfunction is exemplified by many neurological disorders such as amnesia. There are two types of amnesia, anterograde and retrograde. Anterograde amnesia is inability in forming new information, while retrograde refers to the loss of the past memory. As suggested by Cipolotti and Bird (2006), hippocampus’s lesions are responsible for both types of amnesia. According to multiple trace theory, the author suggests that hippocampal region plays a major role in effective retrieving of episodic memory (Cipolotti and Bird, 2006). For example, patients with hippocampal damage show extensively ungraded retrograde amnesia (Cipolotti and Bird, 2006). They have a difficult time in retrieving information from their non-personal episodic events and autobiographical memory. However, this theory conflicts with standard model of consolidation. The difference between these theories suggests that researchers need to do more work to solve this controversy. Besides retrieving information, hippocampus is also important in obtaining new semantic information, as well as familiarity and recollection (Cipolotti and Bird, 2006). For instance, hippocampal amnesic patient V.C shows in ability to acquire new semantic knowledge such as vocabularies and factual concepts (Cipolotti and Bird, 2006). He is also unable to recognize and recall even...
Wilson J.T.L., Teasdale, G.M., Hadley, D.M., & Wiedmann, K.D., Lang, D. (2012). Post-traumatic amnesia: still a valuable yardstick. Journal of Neurology, Neurosurgery, and Psychiatry, 56, 198-201
amygdala and the hippocampus. Those parts of the brain link fear and memory together. With
However, scientists are beginning to uncover that stress can also inhibit the plasticity and neurogenesis within the hippocampus. By inhibiting these processes, stress can negatively influence the mechanism responsible for memory consolidation in the brain. These effects, if not treated promptly with suitable sleep, could have harmful and damaging effects on nerve cells in the hippocampus. By identifying these effects within sleep deprivation, scientists can formulate new effective drugs and mechanisms to enhance memory impairment caused by sleep loss.
According to these two cases, these inspire us to understand that the hippocampus is an important brain region that is used for converting short-term memory into long-term memory.
Rasch, B., & Born, J. (2008). Reactivation and consolidation of memory during sleep. Current Directions in Psychological Science, 17, 188-192. doi: 10.1111/j.14678721.2008.00572.x
Amnesia, a severe long-term memory loss disease, is caused by damaged brain tissue. There are two different types of amnesia. Retrograde amnesia is also known as backward moving. This is when you have a hard time remembering the past, especially episodic memories. This occurs because of memory consolidation. Memory consolidation is the process of a new memory setting until it becomes permanently in the brain. If this process is disrupted, the memory may be lost (Hockenberry and Hockenberry page 265). Anterograde amnesia is also known as forward moving. This is when you are unable to form new
Anterograde Amnesia (AA) is commonly known as short term memory loss. It is the inability to form any new memories after a neurological or psychological trauma in the brain. “Current definitions of anterograde amnesia emphasize the presence of severe and permanent deficits for the recall of recent events (typically with poor recognition) that contrast with intact short-term memory, IQ, semantic memory, skill learning, simple classical conditioning, perceptual learning, and priming” (Aggleton, 2008, p. 1442). Also, according to Aggleton, AA causes the inability to recall autobiographical events (episodic memory). Research shows that damage to the diencephalon or frontal lobe can cause AA. Damage to the diencephalon impairs memory performance because it encodes new experiences for future recall and damage to the frontal lobe of the brain weaken memory performance because the it is involved in regulates access explicit memory (Mendev 2007). Duff, Wszalek, Tranel & Cohen (2008) stated...
The question then becomes whether declarative and non-declarative memory are in fact separate or different manifestations of the same neural process. From research on H.M., we find evidence for the existence of a declarative memory system that is independent of non-declarative memory and other forms of intelligence. H.M. had the capacity to hold information in his head for a period of time, suggesting that his working memory was intact (Squire and Wixted, 2011). Further evidence that not all memory is the same is the fact that H.M. acquired a motor skill despite not being able to remember actually learning the skill, thus showing the difference between episodic and semantic memory. Amnesiacs are able to acquire the perceptual skill of reading mirror-reversed words at a normal rate compared to controls (Cohen and Squire, 1980), demonstrating that the ability to learn new perceptual skills also remains intact. Of the forms of non-declarative memory, procedural memory involves the cerebellum, motor cortex, and basal ganglia (General Intro the Neurobiology…). Thus, non-declarative memory can, in a way, be seen as a more primitive form of memory that is not acquired through the integration and consolidation of neural events in the medial temporal lobe, but rather through learned associations outside of the
...Baddeley (1966) study of encoding in the short term memory and long term memory supports the MSM model on the mode of processing such that words are processed on recall and both models share the same opinion that processing does influence recall. Finally, the MSM model of memory states that all information is stored in the long term memory, however, this interpretation contrasts with that of Baddeley (1974) who argue that we store different types of memories and it is unlikely that they occur only in the LTM store. Additionally, other theories have recognised different types of memories that we experience, therefore it is debatable that all these different memories occur only in the long-term memory as presumed by the multi-store model which states the long term memory store as with unlimited capacity, in addition it also fails to explain how we recall information.
Making and storing memories is a complex process involving many regions of the brain. (3). Most experts agree that we have two stages of memories - short-term memory and long-term memory. Short-term memory is the immediate memory we have when we first hear or perceive someth...
Hippocampus plays an important job in the formation of new memories about experienced events such as the episodic or the autobiographical memory. It is also a part of larger medial temporal lobe memory system responsible for general declarative memory. General declarative memory is a type of memories that can be explicitly verbalized. If damage to hippocampus occurs only in one hemisphere, our brain can still retain near-normal memory functioning. But even so the hippocampus is damage; some types of memory such as abilities to learn new skills will not be affected. The reason is because, some abilities depends on different types of memory and different regions of the brain such as procedural memory. Hippocampus also plays role in spatial memory and navigation. Many hippocampal neurons have “place fields” and the discovery of place cells in 1970’s led to the theory that hippocampus might act as cognitive
In order to understand the functional relationship between learning and memory we have to first define what both learning and memory are. Learning can be described as “the acquisition of knowledge or skills through experience, practice, or study, or by being taught” (Merriam-Webster, 2014). “Memory is the means by which we draw on our past experiences in order to use this information in the present” (Sternberg, 1999). Base on this definitions one can conclude memory is essential part of our lives. Without any memory of the past, we would not be able to operate in the present or reminisce about the future. We would not be able to remember what we did a few days ago, what we have accomplished today, or what we intend to do tomorrow. Without memory our ability to learn would not exist. Learning and Memory are linked to our cognitive abilities as well as that of animals. An example that can be used to show the relationship between learning and memory is the study of how a rat behaves in a maze. As we all know rats have been used in experimental mazes since at least the early 20th century. Hundreds if not thousands of studies have looked at how rats run different types of mazes, from T-maze, to radial arm mazes, and to water mazes. These maze studies help scientist study spatial learning and memory in rats. Maze studies helped us uncover general principles about learning that can be applied to several species, including mankind. In today’s modern societies, mazes tend to be used to determine whether different treatments affect learning and memory in rats. According to Kolata al, 2005 case study the tasks that comprise the learning battery were specifically chosen so that each one placed specific sensory, motor, motivational, and info...
Rasch, Björn, and Jan Born. "About Sleep 's Role in Memory." Physiological Reviews. American Physiological Society, n.d. Web. 06 May 2016.