Short Term Memory example essay topic
Memory is said to be the primary aspect of cognitive processes. Short-term memory, sometimes known as working memory is the component of memory where new information is held while it is mentally processed. It is a temporary holding bin for new information. Short-term memory is also the component of memory where much of our thinking, or information processing occurs.
The capacity of short-term memory is limited and can only hold a small amount of information. Consequently, an item usually remains in short term memory, unless it was rehearsed, for average of 20 to 30 sec. Much effort has gone into trying to analyze how short-term memory recall can be affected by some digressing activity. Pellegrino examined the effect of the different types of distraction and the length of the delay had on retention and recall of a stimulus. Pellegrino reported an experiment in which subjects were presented with (1) either a word or picture and (2) were subsequently distracted by the acoustic (counting form a particular number) or acoustic + visual distraction (counting backwards while trying to locate the shape of a nonlabelabl structure from a matrix of confusing lines). The results showed that recall of pictures were greater for the acoustic whereas the acoustic + visual distraction task together word recall was significantly different.
Pictures were superior to words at all delay intervals under single acoustic distraction, whereas dual distraction consistently reduced picture retention while simultaneously facilitating word retention. Peterson and Peterson (1959) reported a study of the short-term retention of individual verbal items. In this study the results of two identical experiments with the exception of a few conditions were reported. Both experiments examined the progress of retention after the brief presentation of an item. The subjects were presented with a consonant syllable followed by a three-digit number from which they had to count backwards by three's or four's until prompted by the experimenter to stop and recall the consonant syllables. Partial counterbalancing was used to ensure that each syllable occurred equally often over a group at each recall interval.
Subjects were given practice trials of which they were coached on the ways they should respond to the stimulus in the study. The only difference between the two experiments was that the latter was a between-subject study in which the subjects were either given no time, 1 sec. or 3 sec. to rehearse the consonant syllable before starting to count backwards. The results of both experiments showed that the 3-sec. and 18-sec. delay of recall were significantly different from each other. The probability of recall decreased with the duration of the arbitrating activity. Likewise, Bennet Murdock (1961) reported a series of experiments in which a number of different factors that could affect one's memory was examined. Among the three experiments that were reported was the replication of the Peterson and Peterson experiment with the exception of a few conditions.
It was conducted in a series of four sessions, which varied from a single consonant syllable to single, monosyllable non-homophonic words from a list of very common words. The results showed that session 1 and 3 were not significantly different from one another. However, session 2 was highly significant from sessions 1 and 3 combined. Recall seemed to be greater if the items formed a word that can be associated with a particular thing as opposed to the single consonant items. The present study is a replicate of the Peterson and Peterson study.
The independent variable in this study was the rate of the delay before recall. The dependent variable was the mean percentage correct of recall. It is highly anticipated that the results from the present study will be similar to that of the Peterson and Peterson study. It is hypothesized that as the delay period with some form of distraction got longer, the lower the percentage of recall would be. Method Participants Eighteen undergraduate students in an experimental psychology class took part in this study. All the participants were Queens College students of the City University of New York, whom were required to participate in the study.
The sample consisted of sixteen females and 2 males of whom 9 were seniors and 9 were juniors. The mean age of the participants was 24.94 with a standard deviation of 6.89. Sixteen of the participants were right-handed; two were ambidextrous. Vision was normal or corrected for all the participants. Materials Researchers used an experiment, Short Term Memory, a computer based program designed for the disk of the MEL Lab Manual: Experiments, in Perception, Cognition, Social Psychology and Human Factors. The data was recorded through the use of a pen and paper.
The experiment took place in a small classroom where the participants were placed in cubicles where the computers were positioned. Design and Procedure The experiment was a single factor within-subject design with 3 different conditions of 45 different trials. There were 15 trials at each condition. Partial counterbalancing was used to ensure that sequence effects were properly controlled.
The participants in the experiment were randomly assigned to groups, where the professor then gave the regulations for which they were to follow. The following are the instructions that were given to the students by the instructor. In this version, the computer will present a set of three consonants and a three-digit number. The experimenter is to read those aloud to the subject (letter and the numbers), pressing the spacebar as the lasts digit is read.
After that, the subject is to count backwards by threes (out loud) from the number the experimenter read to them, counting in time to the tones that the computer presents once each second. The experimenter is to hit the spacebar each time the subject reports a number. For example, if the number were 765, the subject would say 762,759,756,753,750, and 747, etc. until told to stop. The counting backwards by threes should continue until a different tone is heard.
At that point, the subject is to report the letters they can recall out loud to the experimenter, who enters them into the computer. The computer will then report whether the recall was accurate, and the experimenter should report this information to the subject. The letters must be recalled in the same order in which they were presented. Only a completed recall IN ORDER will be counted as correct.
There will be 45 trials. No practice trials are given, so please read the instructions carefully. Press the spacebar to begin the experiment (James, J.S., Schneider, W. & Rogers, K.A., 1994) After completing all 45 trials, the participants were asked to switch roles such that the experimenter became the participant. The experiment took each participant eighteen minutes to complete. Each participant was tested individually.
Results The results from the data indicated that as the delay period increased, the percentage of recall simultaneously decreased notably as well. An alpha level of. 05 was used for all the statistical tests. As shown in figure 1, the mean of the trials tend to decrease as the distraction period increased.
The proportion of recall in the 18-sec. conditions tends to be increasingly lower than that at the 3-sec. conditions. There appears to be a considerable decrease in the proportion of recall by an average of 17.77%. As for the measures of variability, particularly the standard deviation the participants tended to score within or close to one standard deviation of the mean. The data revealed that the variability at the 9-sec. conditions and the 18-sec. conditions did not differ as much as the variability between the 3-sec. conditions and the 18-sec. conditions. A two-tailed test revealed that the differences were highly significant t (17) = 4.48, p.