A. Evaluate evidence that non-declarative long-term memory is preserved in amnesia.
Amnesic patients tend to suffer from permanent or temporal, normally partial or total loss of episodic memory and an impaired capacity to form and store new memories. On the other hand, they seem to demonstrate unimpaired performance of behaviours involving prior experiences on tests which do not require any intentional or conscious recollection of those experiences (Schacter, 1992). Hence, most amnesic patients demonstrate the ability to retain and learn new behaviours through priming and conditioning, and acquire new perceptual, cognitive, motor and emotional skills which cannot be traced back to an explicit memory but can be demonstrated implicitly.
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The combined findings provide the foundation for the hypothesis that there is more than one kind of memory, or rather that skill-based memories must be organised differently from fact-based memories since the former seem to be preserved in amnesia as opposed to the latter.
Further supportive evidence comes from priming studies; priming refers to the improved capacity for detecting or processing a novel or familiar stimuli based on recent experience (Tulving & Schater, 1990). In a famous study by Heist et al. (1991) amnesic patients and control subjects studied words and non-words. They were then given a perceptual identification test with briefly presented previously studied and unstudied items. Perceptual priming was measured as the increase in the probability of identifying the former versus the letter items. Amnesic patients exhibited entirely normal priming for both old words and non-words. On the other hand, they showed significant impairment in recognizing items that had appeared on the administered test. Priming of non-words did not appear to be based on the activation of words that were phonologically or orthographically similar to the non-words. The non-word results suggest that priming can involve the acquisition of new information, rather than simply the activation of pre-existing representations. Researchers concluded that intact perceptual priming in amnesic patients reflects specific changes
In the last half century several theories have emerged with regard to the best model for human memory. In each of these models there was a specific way to help people recall words and
It is apparent that patient H.M.’s memory has not been affected by any general intellectual loss. H.M has severe anterograde amnesia, but surprisingly has spared implicit memory. Implicit memory is a type of memory in which past experiences aid the presentation of a task without mindful awareness of the experiences. There have been many tests conducted on the patient to test this spared memory.
The 6-hour time point was added as a second experiment to try to unpick a reason for the deficit seen at 24-hours. Again at the 6-hour time point in both the novel object location task and the novel object preference task there is impairment in the animals treated with MPL ability to distinguish between novel and familiar. This indicates that there is a change occurring by the 6-hour time point in some part of the memory. The treatment with 1g/L MPL for 5 days is causing a change that impacts either the consolidation or retrieval of knowledge at these longer time points. The fact that at a 1-hour delay there is no deficit would suggest that treatment with 1g/L MPL for 5 days does not impair the acquisition phase of learning.
Since hippocampus plays an important function in the brain, it has become a great topic for many conducted research not only on human but also animals, specifically primates and rodents. In primate model of amnesia, the experiment is performed through three main tasks – delayed nonmatch to sample, object discrimination paradigm and motor skill learning across multiple trials (Eichenbaum et al, 1992). In delayed non-matching test, both amnesic and intact monkey show nearly same performance rate in remembering objects across delayed in short period of time (Eichenbaum et al, 1992). In contrast, amnesic monkeys show a great impairment for longer delayed conditions, hours, in picking the right non-matched samples (Eichenbaum et al, 1992). Likewise, in object discrimination task, amnesic monkeys are unable to recognize objects, as compared to control monkeys (Eichenbaum et al, 1992).These tests suggest the importance of hippocampus in acquisition of new information and recollection old events from episodic memory. Additionally, hippocampus also contributes largely to relational representation, as a characteristic of declarative memory (Eichenbaum et al, 1992). This can be shown through odor discrimination and place
After a new memory is learnt, it enters the process of encoding during which the memory is labile and capable of disruption until it becomes stabilised over a period of time (Nader & Einarsson, 2010; Nader et al, 2000). This process is called consolidation and originally consisted of the theory that once stabilised in the brain, it remains fixed (Suzuki et al, 2004). This theory has been rebutted by the acceptance of reconsolidation, a theory that imposes the ideology that when memories are retrieved, through similar experiences (Lee, 2009), they become labile until,
Amnesia is a critical health issue that happens to all us in our lifetimes. Whether it is from sports, a health condition that turn for the worst, or our body just slowly deteriorate and break apart. Scientists and doctors collaborate to find a way to prevent amnesia or put it to a standstill. The sole reason why Amnesia struck me is because I personally experience some small form of amnesia. When I was younger, I got hit near my right eyebrow by a hockey puck. I lost consciousness for a minute and woke up on the ground, not remembering what happened and to discovered my head is bleeding. I often find myself forgetting a lot of things such as things that was recently spoken or discussed. However, it is not just me that prompted me to learn and research about Amnesia. My father often forget things as well. He is only in his 50’s and had multiple surgeries that made me wonder if his surgeries has to do anything with it.
Our ability to retain information from our every day experiences is due to our episodic memory (Berk, 238). This research paper examines the effects of genetics as well as the participants’ personal lifestyles in the hopes of assessing the reasons behind the stability and decline in episodic memory (Josefsson et al., 2012). The investigation is important in understanding the development of our episodic memory by knowing what effects our ability to retain every day experiences. It may also help our understanding of how information processing can be improved or stabilized.
On Thursday, March 2nd, 2017 our class had welcomed a guest speaker for our adulthood and aging course. Our guest speaker, Dr. Parks, had spent a considerable amount of time teaching our class about different dimensions and aspects of memory. Although, the class learned a wide array of information; Dr. Parks notable amount of our time presenting information on prospective memory. The term prospective memory can be defined as “memory to perform future actions without specific reminders.” After learning about perspective memory the class had learned additional information about two different types of perspective memory. The first type of perspective memory is event based PM (completed when a cue present); and the other is time based PM (completed at specific time).
Since Nader, Schafe & LaDoux (2000), challenged the previously heralded definition of memory consolidation, an influx of research addressing various theories of; consolidation, reconsolidation and potential clinical implications have surfaced. This essay aims to conglomerate the current understanding of memory reconsolidation, furthermore addressing the resonance upon clinical psychology.
A fundamental aspect of human memory is that the more time elapsed since an event, the fainter the memory becomes. This has been shown to be true on a relatively linear scale with the exception of our first three to four years of life (Fitzgerald, 1991). It is even common for adults not to have any memory before the age of six or seven. The absence of memory in these first years has sparked much interest as to how and why it happens. Ever since Freud (1916/1963) first popularized the phenomenon there have been many questions and few robust empirical studies. Childhood amnesia is defined as the period of life from which no events are remembered (Usher & Neisser, 1993) beginning at birth and ending at the onset of your
built on a combined approach of clinical observation and theoretical model proposals. The former was
Conversely, D.B had intact semantic memory, yet was unable to retrieve personally relevant past memories (Klein, Loftus & Kihlstrom, 2002). Patient D.B, however produced more Essentially, what has been identified through neuroimaging studies (reference) are four regions that comprise the brain’s default mode network and are responsible for prospection and autobiographical memory: the anteromedial prefrontal cortex (amPFC) , the medial temporal lobe (MTL), the posterior cingulate/precuneus (PCC/pCUN) and the lateral parietal and temporal lobes ( Schacter et al., 2012).. With these regions identified, theories of its instantiation came about, such as the constructive episodic simulation hypothesis (Schacter & Addis, 2007). It states that future
I found the most compelling evidence is dissociations between priming and other memory systems. The first piece of this evidence was about intact priming in amnesic patients. It was only briefly stated as the first of five different kinds of dissociations; the priming effects in amnesic patients who cannot remember the study episode in priming experiment are as large as those in normal subjects. But it is convincing enough to infer a single RPS separated from episodic memory. The same type of evidence in the different section also fortifies this inference of PRS. Especially, an example of an alexic patient (P.T.) seemed noteworthy. This patient showed priming effect in a word identification test even though she was only able to perform letter-by-letter
The lexical decision task is often used in tandem with semantic priming in cognitive research involving semantic memory, working memory and psycholinguistics. It is often used to better understand the way in which knowledge in the brain is organized within semantic networks. For example Gadsby, Arnott and Copland (2008) used the lexical decision task with semantic priming in order to examine the working memory capacity and its ability to inhibit dominant responses. In this study they found that when firstly primed with an alternate word to the target word individuals with high working memory capacity were able to better inhibit the dominant response as compared to low capacity individuals. In addition a study by Tulving, Hayman and Macdonald (1991) found that patients with anterograde amnesia were able to learn some semantic information implicitly, as there were priming effects present for previously tested
Case 1 tells the story of Henry Molaison (HM), a man with no memory. He lost his memory due to the operation of suctioned out the hippocampus to treat his epileptic seizures. At that time, it was not known yet that the hippocampus was essential for making memories. After operation, his seizures were significantly reduced, but Henry suffered a global amnesia. Owen et al. (2007) describes patients with global amnesia as perceptive and attentive but with a total loss of short-term memory and some trouble accessing memories of the recent past. Henry could not learn new things as he quickly forgot everything that he had learned. He could learn at a subconscious level only.