After looking though different slides I found an interesting region in the brain. The slide consisted of a the brain cut on the sagittal plane which results in a division of the left and right side of the brain into two equal parts. When finding this area of interest in the mouse brain atlas, it was found to be a couple of sub regions of the hippocampus: CA1 and CA3. After briefly mentioning the importance of these two sub regions, I will focus my attention on the hippocampus as a whole.
According to Eric Kandel, a professor and neuropsychiatrist, the hippocampus has three important regions: CA1, CA3, and the dentate gyrus. CA1 is near the output area of the hippocampus and its individual cells code for space. Since we know the hippocampus has a large involvement in memory, the CA1 region has a large involvement in the long-term memory for space. If there is a lesion in this area, you interfere with memory storage. It is also suggested that the CA1 performs a match–mismatch comparison of memory retrieval with
sensory input. CA1 is considered to be the main output pathway to the Entorhinal cortex and subiculum. CA3 on the other hand, is known to have many excitatory pyramidal cells which project to CA2 and CA1 by
…show more content…
Schaffer collaterals. Unlike CA1, CA3 has a large amount of cells that send recurrent collaterals. Now that these sub regions have been briefly addressed, we can focus our attention on the hippocampus as a whole.
The hippocampus gets its name because its structure is similar to that of a seahorse. It is part of the limbic system, which is the area of the brain associated with emotions and memory. The hippocampus is involved in the storage of long-term memory, especially in declarative memory which is remembrance of things like facts of events. Because of its location as part of the limbic system, the hippocampus also attaches emotions to the memories. It also plays a key role in spatial navigation. There is a dialogue between the hippocampus and the neocortex, and is thought to be the cause of the formation, consolidation, and retrieval of
memories Along with its involvement of long-term memory and spatial navigation, the hippocampus plays a key role in learning and stress regulation. According to a study done, the hippocampus shows an impressive capacity for structural reorganization. This supports neuroplasticity, and it is generally accepted that the hippocampus remains structurally plastic throughout life which is known as long-term potentiation. When damaged, you are unable to form new memories. An early study of hippocampal dysfunction was of patient H.M, who had large portions of the medial temporal lobe when trying to cure him of seizures. Most of his cognitive functions remained intact but he was not able to create new memories for facts or events. Alzheimer’s disease affects the hippocampus first and severely, before other parts of the cortex. As well as in both schizophrenia and some sever depressions, the hippocampus appears to shrink. What I found fascinating, was that there is evidence that this shrinkage can be prevented and maybe even reversed with treatment.
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...
Organized in the class Actinopterygii, seahorses, Hippocampus spp., are marine dwelling organisms found in bodies of water which span from tropical to temperate zones around the Earth. As cited by Foster in Life History and Ecology of Seahorses, research by R. A. Fritschze suggests that the genus Hippocampus diverged at least 20 million years ago from its ancestral origins. Research pertaining to organisms organized under the genus Hippocampus are conflicting in regards to the number species contained within it, although a general figure places the number at around fifty discovered species(website source). These odd-looking organisms reside at shallow depths of less than 30 meters and can be found in habitats containing seagrass beds and coral reefs(Foster 10). Hippocampus spp. are all predatory organisms, their main sources of food consist of small crustaceans and fish, as well as other organisms which are small enough to be consumed(lourie 10). Although Hippocampus spp. are predatory, their size and restricted mobility capabilities place them at risk of being prey for other carnivorous organisms.
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.
Through studies performed on sleep-deprived rats, experimental results have shown a decrease in cellular activity in the hippocampus. The hippocampus is responsible for most of the brain’s memory processing. When entering into sleep deprivation, the brain will experience consequences such as a failure for the hippocampus to encode, consolidate, or retrieve signals powering memory processing. As a result, researchers are looking for cellular characteristics that could lead to further details into the relationship between sleep deprivation and memory impairment. There are several different ways memory can be disrupted, one suggested in being an imbalance of neurotransmitters in the hippocampal region of the brain. Both hormonal and oxidative stress are also factors that are observed to play major roles of memory impairment in the hippocampus. These
Alzheimer’s is a progressive, degenerative disease of the brain and individuals with the disease suffer from many symptoms such as memory loss, agitation, impaired judgment, and difficulty communicating with others. The different lobes affected include the parietal lobe which deals with language, temporal lobe which deals with memory and frontal lobe which deals with behavior and judgment. The specific type of memory loss that an Alzheimer’s patient deals with is declarative memory. Declarative memory is remembrance of facts such as people’s names, what their faces look like and important dates from our past (Marieb and Hoehn 2013). The formation of these memories can only happen when the temporal lobe or more specifically the hippocampus are able to receive acetylcholine inputs. Patients with Alzheimer’s loose this input which prevents making new memories and remembering old ones (Marieb and Hoehn 2013).
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
lobes 1. The second is the hippocampus (meaning seahorses in Greek) which it resembles2) which is located below the cerebral cortex and responsible for short term memory. If we study samples of these two sections, we would find three. irregularities which are not found in normal brain matter. These three are called neurofibrillary tangles, neuritic plagues and granulovacuolar.
The researchers suggested that by increasing hippocampal neurogenesis in adult rats, the existing memories tended to weaken thereafter and retrieval of contextual fear memories would be difficult. In contrast, when the hippocampal neurogenesis was reduced, the existing memories would be more protected and retrieval of fear memories would be possible afterward. Frankland et al., (2013) discussed the effects of hippocampal neurogenesis on infantile amnesia by comparing guinea pigs to rats or mice. Researchers suggested that guinea pigs are born with most of their neurons complete and don’t experience as much neurogenesis when they are infants as mice and rats. Therefore, they were shown to retain memories of special discrimination as well as adult guinea pigs. This demonstrates that infant guinea pigs do not experience infantile amnesia due to their low levels of postnatal hippocampal
The term "spatial cognition" is used to describe those processes controlling behavior that must be directed at particular location, as well as those responses that depend on location or spatial arrangement of stimuli (1). Navigation refers to the process of strategic route planning and way finding, where way finding is defined as a dynamic step-by-step decision-making process required to negotiate a path to a destination (2). As a spatial behavior, negotiation demands a spatial representation; a neural code that distinguishes one place or spatial arrangement of stimuli from another (1). What, though, serves as such a representation in navigation and from where are these representations derived? The processes occurring within the hippocampus provide such representations.
Chemically, the brain has a myriad of purposes, but one of the most interesting is its capability to process memory. The brain is able to fill in gaps in our vision and memory and store the information
When diagnosed with probable Alzheimer's disease the effect of plagues and tangles are now starting to be seen in many ways including, memory loss in which individuals may have trouble learning new information and consistently ask the same question multiple times, along with disorientation which is an indication that the Hippocampus is being affected by plagues and tangles. The Hippocampus is usually one of the first areas affected by the disease (Brayne, 2014).
amygdala and the hippocampus. Those parts of the brain link fear and memory together. With
there has been a lot of talk of left brain and right brain people. Levy's
Long-term memory is how humans process in the present, recall information from the past, or think about the future. Without long-term memory one cannot remember past memories, today, or what we may plan to do in the future. On top of that, there is no learning without long-term memory and the progress that we see today in our fast pace driven world would not exist. This is why the study and understanding of long-term memory is important for further knowledge of human nature. The long-term memory itself takes in many different forms of information including images, sounds, and meaning. The orientation of memory encompasses three important stages and the first is encoding. Encoding takes places in different locations inside the brain and this
The human body is divided into many different parts called organs. All of the parts are controlled by an organ called the brain, which is located in the head. The brain weighs about 2. 75 pounds, and has a whitish-pink appearance. The brain is made up of many cells, and is the control centre of the body. The brain flashes messages out to all the other parts of the body.