Data also taken from http://www.ahaf.org/alzdis/about/brain_headBorder.jpg
The image on the left is the outside of the brain, viewed from the side, showing the major lobes (frontal, parietal, temporal and occipital) and the brain stem structures (pons, medulla oblongata, and cerebellum).
The image on the right is a side-view showing the location of the limbic system inside the brain. The limbic system consists of a number of structures, including the fornix, hippocampus, cingulate gyrus, amygdala, the parahippocampal gyrus and parts of the thalamus.The hippocampus is one of the first areas affected by Alzheimer's disease. As the disease progresses, damage extends throughout the lobes.
There are 3 areas of the brain which are
Amygdala – limbic structure involved in many brain functions, including emotion, learning and memory. It is part of a system that processes "reflexive" emotions like fear and anxiety.
Limbic system – a group of interconnected structures that mediate emotions, learning and memory.
Temporal lobe – processes hearing, memory and language functions.
I found some artical at http://biology.about.com/b/2004/12/09/brain-anatomy-hippocampus.htm
which tells us that the hippocampus is the part of the brain that is involved in memory forming, organizing, and storing. It is particularly important in forming new memories and connecting emotions and senses, such as smell and sound, to memories.
This makes me question the integrity of the other site so I need to find some more evidence. What is the hippocampus?
Taken from http://en.wikipedia.org/wiki/Hippocampus
The hippocampus is a part of the forebrain, located in the medial temporal lobe. It forms a part of the limbic system and plays a part in long term memory and spatial navigation. Humans and other mammals have two hippocampi, one in each side of the brain.
The name derives from its curved shape in coronal sections of the brain, which resembles a seahorse (Greek: hippos = horse, kampi = curve).
I have found out that it is just part of the Limbic System which is explained above. It was just a more accurate description of which part of the system focuses on memory. The hippocampus is still yet to be fully understood and we are unsure of its precise role.
Damage to the hippocampus usually results in profound difficulties in forming new memories (anterograde amnesia), and normally also affects access to memories prior to the damage (retrograde amnesia). Although the retrograde effect normally extends some years prior to the brain damage, in some cases older memories remain - this sparing of older memories leads to the idea that consolidation over time involves the transfer of memories out of the hippocampus to other parts of the brain.
I read this further down on wiki which tells us that this part of the brain has been seen to form new memories and not recall them. If this part of the brain is damaged it leads to new memories from being created. Like in the movie I have reviewed '50 First Dates' the main character can't form new memories after a day, this might have been due to damage in her hippocampus from a car accident.
London's taxi drivers must learn a large number of places — and know the most direct routes between them (they have to pass a strict test, The Knowledge, before being licensed to drive the famous black cabs). A study at University College London by Maguire, et al (2000) showed that part of the hippocampus is larger in taxi drivers than in the general public, and that more experienced drivers have bigger hippocampi.
I also found this quite interesting, that the hippocampi is larger in people who need to access large amounts of information on a regular basis, like a london taxi driver. I could use something like this in my work, maybe some style of photography showing the area of the brain enlarged, like a revirsed fish eye effect showing the center of the image to be large.
http://biology.about.com/library/organs/brain/blhippocam.htm
Here i found a little list in bullet form about the
Function:
* Consolidation of New Memories
* Emotions
* Navigation
* Spatial Orientation
Location:
* The hippocampus is a horseshoe shaped sheet of neurons located within the temporal lobes and adjacent to the amygdala.
Image taken from http://www.technovelgy.com/graphics/content/hippocampus.jpg
What is the Temporal Lobe?
The superior temporal gyrus includes an area (within the Sylvian fissure) where auditory signals from the cochlea (relayed via several subcortical nuclei) first reach the cerebral cortex. This part of the cortex (primary auditory cortex) is involved in hearing. Adjacent areas in the superior, posterior and lateral parts of the temporal lobes are involved in high-level auditory processing. In humans this includes speech, for which the left temporal lobe in particular seems to be specialized. Wernicke's area, which spans the region between temporal and parietal lobes, plays a key role (in tandem with Broca's area, which is in the frontal lobe). The functions of the left temporal lobe are not limited to low-level perception but extend to comprehension, naming, verbal memory and other language functions. Sound processing is controlled by the temporal lobes- in the Broca’s area and Wernicke’s area.
There is nothing much about memory and the temporal lobe on wiki accept it tells us that tghe fuctions of the left side are linked with verbal memory and language. There is another parag
The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemispheres) are thought to be involved in episodic/declarative memory. Deep inside the medial temporal lobes, the hippocampi seem to be particularly important for memory function - particularly transference from short to long term memory and control of spatial memory and behavior.
This links into what i have already looked (the hippocampi) but i have found at that it is involed with episodic memory, which I previously looked at in LTM (long term memory) post.
What is the amygdalae?
(taken from wiki)
The amygdalae are almond-shaped groups of neurons located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.
The amygdalae also are involved in the modulation of memory consolidation. Following any learning event, the long-term memory for the event is not instantaneously formed. Rather, information regarding the event is slowly assimilated into long-term storage over time, a process referred to as memory consolidation.
During the consolidation period, the memory can be modulated. In particular, it appears that emotional arousal following the learning event influences the strength of the subsequent memory for that event. Greater emotional arousal following a learning event enhances a person's retention of that event. Experiments have shown that administration of stress hormones to mice immediately after they learn something enhances their retention when they are tested two days later.
I find this really intesting, i know that emotions enchanced memory. As a widely used example a lot of people have a stong memory of 9/11 when the twin towers fell. People can tell you where they where and what they were doing, even what they were wearing or eating when the event happened. This is due to an emotion repsonse enhancing the memory. Looking at the encahncement of memory is just another area I have overlooked untill now but could go onto my research list to look further into it.
The amygdalae, especially the basolateral nuclei, are involved in mediating the effects of emotional arousal on the strength of the memory for the event, as shown by many laboratories including that of James McGaugh. These laboratories have trained animals on a variety of learning tasks and found that drugs injected into the amygdala after training affect the animals' subsequent retention of the task. These tasks include basic classical conditioning tasks such as inhibitory avoidance, where a rat learns to associate a mild footshock with a particular compartment of an apparatus, and more complex tasks such as spatial or cued water maze, where a rat learns to swim to a platform to escape the water. If a drug that activates the amygdalae is injected into the amygdalae, the animals had better memory for the training in the task. If a drug that inactivates the amygdalae is injected, the animals had impaired memory for the task.
I find this VERY intresting, the fact that taking drugs can enhance your memory. I dont know the side effects of the drug but to me it seams like an amazing idea to use it. I can think of many purposes where lives could be saved if the drug was used with teaching, an example would be the training of soldiers or even more so people within the medical profession to help them have a better memory of the tasks they were to perform. Children in school would have better memories of there teaching, surly allowing faster advancement.
Evidence from work with humans indicates that the amygdala plays a similar role. Amygdala activity at the time of encoding information correlates with retention for that information. However, this correlation depends on the relative "emotionalness" of the information. More emotionally-arousing information increases amygdalar activity, and that activity correlates with retention.
What is the Temporal Lobe?
The superior temporal gyrus includes an area (within the Sylvian fissure) where auditory signals from the cochlea (relayed via several subcortical nuclei) first reach the cerebral cortex. This part of the cortex (primary auditory cortex) is involved in hearing. Adjacent areas in the superior, posterior and lateral parts of the temporal lobes are involved in high-level auditory processing. In humans this includes speech, for which the left temporal lobe in particular seems to be specialized. Wernicke's area, which spans the region between temporal and parietal lobes, plays a key role (in tandem with Broca's area, which is in the frontal lobe). The functions of the left temporal lobe are not limited to low-level perception but extend to comprehension, naming, verbal memory and other language functions. Sound processing is controlled by the temporal lobes- in the Broca’s area and Wernicke’s area.
There is nothing much about memory and the temporal lobe on wiki accept it tells us that tghe fuctions of the left side are linked with verbal memory and language. There is another parag
The medial temporal lobes (near the Sagittal plane that divides left and right cerebral hemispheres) are thought to be involved in episodic/declarative memory. Deep inside the medial temporal lobes, the hippocampi seem to be particularly important for memory function - particularly transference from short to long term memory and control of spatial memory and behavior.
This links into what i have already looked (the hippocampi) but i have found at that it is involed with episodic memory, which I previously looked at in LTM (long term memory) post.
What is the amygdalae?
(taken from wiki)
The amygdalae are almond-shaped groups of neurons located deep within the medial temporal lobes of the brain in complex vertebrates, including humans. Shown in research to perform a primary role in the processing and memory of emotional reactions, the amygdalae are considered part of the limbic system.
The amygdalae also are involved in the modulation of memory consolidation. Following any learning event, the long-term memory for the event is not instantaneously formed. Rather, information regarding the event is slowly assimilated into long-term storage over time, a process referred to as memory consolidation.
During the consolidation period, the memory can be modulated. In particular, it appears that emotional arousal following the learning event influences the strength of the subsequent memory for that event. Greater emotional arousal following a learning event enhances a person's retention of that event. Experiments have shown that administration of stress hormones to mice immediately after they learn something enhances their retention when they are tested two days later.
I find this really intesting, i know that emotions enchanced memory. As a widely used example a lot of people have a stong memory of 9/11 when the twin towers fell. People can tell you where they where and what they were doing, even what they were wearing or eating when the event happened. This is due to an emotion repsonse enhancing the memory. Looking at the encahncement of memory is just another area I have overlooked untill now but could go onto my research list to look further into it.
The amygdalae, especially the basolateral nuclei, are involved in mediating the effects of emotional arousal on the strength of the memory for the event, as shown by many laboratories including that of James McGaugh. These laboratories have trained animals on a variety of learning tasks and found that drugs injected into the amygdala after training affect the animals' subsequent retention of the task. These tasks include basic classical conditioning tasks such as inhibitory avoidance, where a rat learns to associate a mild footshock with a particular compartment of an apparatus, and more complex tasks such as spatial or cued water maze, where a rat learns to swim to a platform to escape the water. If a drug that activates the amygdalae is injected into the amygdalae, the animals had better memory for the training in the task. If a drug that inactivates the amygdalae is injected, the animals had impaired memory for the task.
I find this VERY intresting, the fact that taking drugs can enhance your memory. I dont know the side effects of the drug but to me it seams like an amazing idea to use it. I can think of many purposes where lives could be saved if the drug was used with teaching, an example would be the training of soldiers or even more so people within the medical profession to help them have a better memory of the tasks they were to perform. Children in school would have better memories of there teaching, surly allowing faster advancement.
Evidence from work with humans indicates that the amygdala plays a similar role. Amygdala activity at the time of encoding information correlates with retention for that information. However, this correlation depends on the relative "emotionalness" of the information. More emotionally-arousing information increases amygdalar activity, and that activity correlates with retention.
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