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Brown Peterson Task
The Brown Peterson task is one of the most commonly used methods for testing short-term memory. The Brown Peterson task is widely used in clinical neuropsychology to test for short term memory and also be used to understand working memory. The Brown Peterson task reveals that there is a short term and long term memory component for retrieval performance. * Here is how it works: individuals asked to recall items on a list after they have delays in which they perform an interference task such as mental addition. The reason for the delayed interference task is because it requires mental rehearsal, which causes a delay in recall performance. This delayed interference task also has an impact on the forgetting function. Another effect on recall is, the more complex the interference task; the lower the number of items that can be recalled from the list.

The Brown Peterson task has also been used to test short-term memory in relation to educational level and age. In a particular study: education level was related to performance on the Brown Peterson task. Individuals with a lower education level reported fewer items compared to those with a high education level. The impact of education was related to the type of interference task. For example, individuals with a higher education level were less likely to be affected by difficult cognitive tasks compared to those with a low education level. Age did not have an affect on the Brown Peterson task in this experiment. However, previous studies have produced both negative and positive results with relation to age on the Brown Peterson task. * . *

History of Brown Peterson task
In previous studies, most researchers have found no age differences in short term forgetting using the Brown Peterson task. However, Inman and Parkinson have identified and corrected methodological flaws of the Brown Peterson task in earlier studies. They found that the probability of short-term recalled decreased a faster rate in old people compared to young people. They also found that age differences were removed when memory capacities were equated for young and old adults by showing them the memory lists before a trial until a criterion of recall was found. Various questions regarding the theory and empirical evidence still remain regarding the Brown Peterson task forgetting among different ages. An important issue with the Brown Peterson task is to investigate age differences in passive forgetting process or the integration of age differences in passive processes with differences in age differences in active list-relate processing. Parkinson et al, thought it was important to complete this task in a setting wit divided attention in which list retention and the distractor task processing would compete for the same limited attentional resources. They predicted that older adults would have poorer recall due to their decreased ability to divide attention. There has also been much controversy with the Brown Peterson task in regards to whether it fits into the existing stimulus-response interference theory. However, many researchers agree that the Brown Peterson task demands on clarification in terms of retrieval processes that go further than the original hypothesis of simple trace decay.

Differences in BP Recall as a Function of Age and Retention Interval
In the following study, the researchers were interested in testing the differences in the Brown Peterson task recall as a function of age and retention interval. The researchers individually tested all participants by giving them a letter span test prior to the Brown Peterson task. The participants completed two Brown Peterson trials and there were five minute breaks between them. The Brown Peterson task consisted of a memory set (3, 4 or 5 letters) and an interpolated task (“sum” or “read” digit pairs). Three blocks of forty trials were run, one block each with the memory sets (3, 4 and 5 letters.) Letters were presented on the same display used for letter span testing. The letter presentation was sequential in the same location at the centre of the display at a rate of two letters per second. Each letter was on display for 220 ms. On each trial a new series of letters was presented; and of these letters they were selected at random. Next, the participants were asked to read each letter aloud when it was presented. The results indicated that the span was a much bigger predictor of performance than age. However, age was associated with the likeliness to make omission errors, but this wasn’t significant overall when span was included. These findings match what has been found in previous studies. . *

When do Age Differences Effect Performance?
In the following study, age differences had an effect on the Brown Peterson task only when recall required secondary memory. Age differences did not have an effect on primary memory. Primary memory is tested for when recall follows a three second delay and secondary memory is recall following an eighteen second delay. The effect of secondary memory demonstrates that older adults have worse recall than younger adults. It is important to note that this effect is not caused by an increase in the rate of forgetting by primary memory. *

Consequences of Findings with Brown Peterson Task with Memory Span in 1960s
There has been controversy over the need to postulate two stores. The philosophy of science argument is relevant, because a more parsimonious theory is better than a more complicated one if it can explain the same findings. This is the principle of Ocham's razor. Several findings indicate that the single-store theory is not supported. The most important discovery was made by psychologist Brenda Milner. She made the first clear-cut demonstration of amnesia in association with damage in specific brain strucure (medial temporal lobes) in patient H.M. SHe established new research field aiming to link specific memory functions to specific brain regions. The clasic findings in amnesic patients indicate normal short term memory cpacity on digit-span task, normal forgetting curve on Brown Peterson task and normal recency effect but impaired primacy effect on the list learning task. This suggest that long term memory but not short term memory is affected by amnesia. *

Amnesic Patients and the Brown Peterson Task
The Brown Peterson task has been used in combination with the Huppert and Piercy task to test whether amnesic patients forget information abnormally fast. The Brown Peterson task traditionally measures verbal recall and the Huppert and Piercy task measures memory for visual information. The Brown Peterson task is responsible for analyzing recall, whereas the Huppert and Piercy task tests for recognition of information. The major difference between these two methods is that the Brown Peterson task measures the rate of forgetting at short delays (a few seconds) and the Huppert and Piercy task measures forgetting at longer delays (10 minutes or more). Together, these tasks are used to measure the forgetting rate of amnesic patients. In the following study, researchers investigated forgetting rate in amnesic patients, which had medial temporal lobe damage or diencephalic damage. The researchers modified the classic Brown Peterson task. They continued to use relatively short delays (7-120 seconds), but they tested for recognition as opposed to recall. The researchers also used a matching method at the earliest delay, which is similar to the Huppert and Piercy task. The results of this study indicated that there was significantly abnormally fast forgetting in both temporal lobe and diencephalic amnesic patients for delays which were more than 120 seconds. These results are important, because it indicates that both types of amnesic patients suffer from abnormally fast forgetting. Future studies should test whether rapid forgetting found in the particular experiment relates to other information such as faces or shapes and why precise-matching recognition has an impact on rapid forgetting. The results also demonstrate that amnesic patients have a memory impairment at much shorter delays at which material is lost much more quickly than healthy individuals in this particular study. The results of this particular study differ from previous studies, which suggest that amnesic patients do not have accelerate forgetting on either task. *

Implications of Brown-Peterson Task
There are various implications of the Brown Peterson task. First, it is useful for understanding short term memory deficits in patients with Alzheimer’s disease, understanding normal age differences in problem-solving and cognition. Also, the effects of the Brown-Peterson task reveal that decay and perturbation are responsible for retroactive interference .*. *.

The Modified Version of the Brown Peterson Task
The brown Peterson task was modified to test working memory in amnesic patients. The modified brown Peterson task: amnesic patients were presented with either a high or low frequency word or non-word, for 4-8 seconds. Working memory may be impaired in amnesia for tasks that require recalling novel/new stimuli, but working memory will remain intact for information that is familiar and easy to remember. *

Previous studies have shown that exercise have an affect on specific types of cognitive performance such as reaction time, visual search, mathematics and decision making. There is less evidence that exercise facilitates memory. In this particular experiment, individuals completed the Brown Peterson task prior to and following 40 minutes of aerobic exercise. Their performance on this task did not change. * 	Alzheimer patients in the BP task is due to trouble renewing or updates information in working memory, which means that there are problems in the central executive. Types of errors include: confusions, perservations, omissions, order alterations. The rate of forgetfulness across control group and Alzheimer patients was similar. * Previous research has shown that patients with schizophrenia have deficits in processes that are linked to working memory. The modified Brown Peterson task used to compare individuals with schizophrenia vs control group. The results indicated that there was rapid decline in schizophrenia patients. There were also more intrusion errors.

Alternative Traditional Use of the Brown Peterson Task
There are other various uses of the Brown Peterson task. For example, it can be used as an attempt to eliminate as completely as possible as maintenance or elaborative rehearsal during the retention interval. In the following study, the purpose was to place all attentional resources in the distractor activity so that only the effects of passive forgetting processes would be observed in recall performance. The results revealed that young adults have greater attentional capacity to process the distractor task and to simultaneously engage in maintenance and/or elaborative rehearsal. This is in comparison to elders. *

Further Research
In future studies, researchers are interested in comparing performances of old and young adults across multiple memory task; storage and retrieval deficits relationship with aging. *