Explanations Of Forgetting!


Psychology Retake! Mind Map on Explanations Of Forgetting!, created by 06ballgo on 06/04/2013.
Mind Map by 06ballgo, updated more than 1 year ago
Created by 06ballgo almost 10 years ago

Resource summary

Explanations Of Forgetting!
  1. Trace Decay: Information that enters the STM leaves a trace in the brain due to the excitation of nerve cells. This neural activity gradually dies away unless the material is rehearsed.
    1. Hebb (1949) - Argued that whilst learning is taking place, the engram which will eventually be formed is very delicate and liable to disruption because it is an active trace. With learning, it grows stronger until a permanent engram is formed.
      1. Some researchers argue that if knowledge and skills (in LTM) are not used and practised, then the engram will decay.
        1. Research Study: Waugh And Norman (1965) Aim: To investigate STM using a serial probe technique and support trace decay as a theory. Method: A repeated measures design, was conducted where participants were presented with lists of 16 digits at a rate of one to four per second. The last digit, known as the probe, occurred once before in the list and the task was to recall the digit which had followed it. It was predicted that participants would recall the digit more accurately if they were presented rapidly (four per second) as there would be less time for the trace to decay, than if they were presented more slowly (one digit per second) Results: There was no relationship between speed of presentation and recall, which suggested trace decay was not a major source of forgetting on this task. Conclusion: Waugh and Norman concluded that forgetting is probably better explained by interference rather than decay.
          1. Evaluation: Lacks ecological validity as the tasks set were artificial and therefore may not be relevant to everyday life.
            1. Evaluation of Trace Decay: - Difficult to test trace decay theory because if participants are tested after different time periods they could be rehearsing. Therefore strengthening the trace. Forgetting could be due to interference from the task rather than decay of the memory trace, - Trace decay theory has difficulty dealing with situations where items which cannot be remembered at one time can be remembered at a future time, even though no additional presentations have been made. - Experiment by Peterson and Peterson is used as evidence for the role of decay in STM, as their findings show that after 18 seconds the trace has almost completely decayed when rehearsal is prevented. - Waugh and Norman who set out to support trace decay, concluded that interference is the most likely cause of forgetting in STM.
        2. DISPLACEMENT THEORY: Explains forgetting from the STM in terms of the limited capacity of this store. It suggests that there are a limited number of 'SLOTS' for information in STM (approx. 7 suggested by Miller) and when the system is 'FULL' the oldest material is 'PUBLISHED OUT' or displaced by incoming information.
          1. The study by Waugh and Norman, using their serial probe task, offers support for the displacement theory of forgetting. They found that if the probe was one of the digits at the beginning of the list, recall was small because later digits would have displayed earlier ones. However, if the probe was presented towards the end of the list, recall was high, since the last digits would still be available in short term memory. the poorer recall of items in the middle of the serial position curve could also be attributed to displacement.
            1. Evaluation of Displacement: ~ Displacement theory seems to give an adequate account of forgetting from STM when applied to the multi store model of memory. Empirical evidence, such as Murdock's primary/recency experimental findings, offers support for the displacement theory. However, more recent models of memory, such as the working memory model, have indicated that STM is much more complex than the unitary, limited capacity short- term store first proposed by Atkinson and Shiffrin's multi-store model of memory.
          2. Interference Theory: ~ Is concerned with what occurs before, during and after learning. At the beginning of the storage process, interference can prevent new information from passing from STM to LTM. In LTM, as the store of information grows, there will be increasing interference between competing memories.
            1. There are Two types of Interference: ~ Proactive interference, where earlier learning interferes with what you are trying to learn at present. E.G. you have learnt Spanish and are now having difficulty learning French. ~ Retroactive interference, where more recent learning interferes with the recall of earlier material. E.G. you know your present mobile number but cannot now remember your previous one.
              1. Research Study: Keppel and Underwood (1962) Aim: To investigate the effects of proactive interference on recall from memory. Method: In a repeated measures design, participants were given a series of trails where they had to learn trigrams (for example TXK) and then count backwards for 3,9 or 18 seconds (the independent variable). The order of testing was balanced to control for order effects. The dependent variable was the recall of the trigram. Results: On the first trail, performance was almost 100 per cent even though some participants had only 3 second intervals whilst others had 18 seconds. On the second and third trials, performance falls steadily as the interval increases. If decay is the sole explantation for forgetting, performance should fall as the interval increases on the first trail as well as subsequent trails. Conclusion: The inferior performance on later trails was due to interference, the first trigram learned is remembered perfectly.
                1. There is no preceding item to interfere. This type of interference is proactive because earlier learning of trigrams interferes with later learning. Evaluation: This study has low ecological validity as this situation would not arise in real life.
                  1. Evaluation of Interference Theory: ~ The strongest support for interference theory comes from lab studies such as the Keppel and Underwood study. However, such lab studies tend to use nonsense syllables as the stimulus material. When meaningful material is used, interference theory suffers as a general theory of forgetting because the situations it best deals with are rarely encountered in everyday life. Studies such as Baddeleys lack ecological validity.
                2. Lack Of Consolidation: ~ Time-dependent changes occur in the nervous system as a result of learning. In order for information In STM to become an LTM, it must go through a process known as consolidation. During consolidation, STM is repeatedly activated. If something interrupts the process, say a bang to the head, then STM cannot be consolidated and memories cannot be 'STORED' for long-term access.
                  1. Research Study: Yarnell And Lynch (1970) Aim: ~ To investigate memory loss due to concussion. Method: ~ A field study was carried out with American footballers who were concussed for a brief period of time during a game. They were approached immediately as they regained consciousness and asked for details of the events that occurred in the game just prior to the injury. They were asked again 20 minutes later. Results: ~ Accurate information was given when the footballers were questioned immediately after they regained consciousness, but the same information was not available 20 minutes later. Conclusion: ~ The consolidation process had been disrupted and therefore the information about the game was not available in long-term store. Evaluation: ~ Field study, high in ecological validity. Problems occurred with control however. Ethical implications when questioning patients when they had only just become conscious.
                    1. Evaluation Of Lack of Consolidation: ~ Patients who have been concussed often suffer retrograde amnesia, which is a loss of memory for events prior to the concussion. This may be because the consolidation process has been interrupted. ~ Electro- convulsion therapy (ECT) causes memory loss for events just before the therapy is given. Evidence suggests that after a one-hour delay between learning and ECT, perfect retention occurs. This suggests that the essential consolidation period required, to ensure information reaches long-term store., is up to one hour. There is evidence from both animals and humans to support the theory that a consolidation process is necessary to prevent memory disruption and loss.
                      1. Retrieval Failure: ~ According to retrieval failure theory, memories cannot be recalled because the correct retrieval cues are not being used. The role of retrieval cues is demonstrated by the 'TIP OF THE TOUNGE' phenomenon, in which we know that we know something but cannot retrieve it from LTM at that particular time. Tulving ~ Investigated retrieval failure in LTM. He gave participants a list of words and then asked them to write down as many as they could remember in any order. Later participants were asked to recall them a second and then a third time. Tulving found that not all of the same words were recalled across the three occasions, and one word was recalled on the third occasion that had not been recalled on the earlier trails. These findings cannot be explained by trace decay because if the trace had decayed it would have never be available, but retrieval failure theory would argue that different retrieval cues were used on the three occasions.
                        1. This resulted in the difference in recall.
                          1. Tulving used the term 'CUE DEPENDENT FORGETTING' to explain that in the same cues are not present at recall as during the original learning, then recall is poor. There are two types of cue-dependent forgetting:
                            1. CONTEXT-DEPENDENT FORGETTING ~ Which occurs if the relevant environmental variables that were present when learning took place are missing at recall, these variables act as external cues. STATE-DEPENDENT FORGETTING ~ which occurs in the absence of relevant psychological or physiological variables that were present during learning, these variables act as internal cues. A study by Bower (1981) showed that when the mood of participants at learning and recall was matched recall was superior to mismatch of mood at learning and recall.
                              1. Research Study: Godden and Baddeley. Aim: ~ To see if cues from the environment affect recall. Method: ~ Field experiment was carried out with deep- sea divers who learned lists of words either on land or underwater (independent variable). Recall of words (dependent variable) was then tested in the same or different context. Results: ~ Those who learned and recalled in different contexts, showed more than a 30 per cent deficit compared to those who learned and recalled in the same context. Conclusion: ~ Environmental context affects memory, and superior recall occurs when environmental conditions at learning and recall match. Evaluation: ~ Although this was a field experiment which means it is more ecologically valid than controlled lab studies, the extreme conditions do not really reflect memory in everyday conditions.
                                1. Evaluation of Retrieval failure: ~ Explains things that cannot be explained by trace decay theory. ~ Lots of empirical evidence to support Cue-dependent forgetting. ~ However, evidence has been criticised, E.G. Bowers study manipulating the mood of participants under hypnosis has never been replicated. This study also suffers from dubious ethics. In addition studies have also been carried out in fairly extreme conditions or where the status is very different whereas in real life we rarely have to recall things under such extreme conditions. These studies can therefore lack ecological validity.
                                  1. Motivated Forgetting Theory: ~ Suggests that we may be motivated to forget. Freud says that some experiences are so painful that if they were allowed to enter consciousness they would produce overwhelming anxiety. Instead, these experiences are repressed and stored in the unconscious, thereby becoming inaccessible. In motivated forgetting, the original experience has been stored but it has now become inaccessible. The most likely outcome of an individual trying to retrieve this memory is that it is more likely then to become repressed.
                                    1. Research Study: Glucksberg and Lloyd (1967) ~ Aim: To investigate motivated forgetting. Method: ~ Repeated design experiment participants are required to learn a paired-associate list of words. They were then asked to read a second list of words some of which were related to the B words on the paired-associate list. The related words on the second list were accompanied by an unexpected and unavoidable electric shock. Participants were then asked to recall the original A-B list of paired associate words (dependent variable) Results: ~ The B words that were related to the second list of words leanrt were forgotten significantly more often than the control words. Evaluation: ~ Ethical implications around the issues of deception and use of electric shocks in this study. motivated forgetting is also concerned with emotional and personal events which could effect participants.
                  Show full summary Hide full summary


                  Unit 1 Sociology: Family Types
                  Spanish: Grammar 3.2
                  Selam H
                  GCSE PHYSICS: Energy Transfer
                  Mind Maps with GoConqr
                  Manikandan Achan
                  P1 quiz
                  I M Wilson
                  Chemistry (C3)
                  Amy Lashkari
                  The Rise of the Nazis
                  The Circulatory System
                  Shane Buckley
                  An Timpeallacht (Foclóir)
                  Sarah Egan
                  Writing successful GCSE English essays
                  Sarah Holmes
                  What You Can Do Using GoConqr
                  Micheal Heffernan