PSYCHOLOGY Essay, Research Paper
The intention of this essay is to discuss the assertion that the human memory is fragile, in light of psychological research concerning encoding, storage and retrieval. This is a subject area with a vast quantity of information to draw from and to include all this in the essay would make it far too long. Therefore, for each of the process areas, one example has been researched and discussed.
The conclusion of this essay is that from the three examples described, it would appear that the human memory is indeed fragile and able to be influenced even without a person?s knowledge. Appreciation and understanding of these weaknesses is of great importance in the criminal justice system. As police officers we have a duty to search for the truth, not a vague idea of what it may be.
The process that will be discussed under this heading is stress of witnesses and how that effects encoding of memories.
It would be reasonable to suppose that witnessing or being the victim of a serious crime, a subject would feel the affects of stress. It is how, if at all, this has a bearing on the encoding process for those memories, and the impact that has on investigations.
There are two main applications relating to stress in this section. The first relates to the YERKES-DODSON Law, describing the basic relationship between a crime and a witness?s ability to recall accurate detail (Yerkes & Dodson 1908 as stated in Gruneberg & Morris 1992). This is described as being an inverted U shape curve and states that performance related to stress occurs in a curvilinear fashion. Very low levels of stress produces poor performance, moderate levels of stress facilitate performance and excess amounts of stress hinder performance and bring it back down. The function of the U will alter along with the different way people deal with stress and the circumstances of the to-be-remembered (TBR) event.
Peters ((1988) as stated in Grunberg & Morris 1992) supported Yerkes & Dodson?s hypothesis with his empirical studies. He concluded that stress directly affected the ability of a witness to report crime. His experiment studied subjects meeting a nurse who injected them and a researcher who did not. Then one day and one week later photographs were shown to the subjects of these two people. From this he found that he received better descriptions and identifications from the photographs of the researcher than of the nurse. This he concluded demonstrated that as arousal increases, much beyond normal, accuracy of the memory suffers.
The second application in this section comes by way of an opposing theory to that of Yerkes & Dodson and Peters. Laboratory studies conducted by various professionals (Hever & Reisberg 1990; Christianson, Loftus, Hoffman & Loftus 1991; Christianson & Loftus 1991 and Yuille & Cutshall 1986 as stated in Gruneberg & Morris 1992) concluded that high levels of stress does not necessarily lead to poor memory.
The study conducted by Yuille & Cuthall ((1986) as stated in Milne & Bull 1999) indicated that following a highly stressful incident (a homicide) witnesses accuracy rate was 93% when interviewed two days after the TBR event. Even four to five months later the accuracy rate was 88%. Christianson & Hubinette ((1993) as stated in Milne & Bull 1999) with their study of bank tellers following an armed robbery, also supported this theory with the accuracy of their information. However, both of these studies looked at the accuracy or quality of the information from the witnesses, not the quantity.
These studies only recorded subjects that were in close proximity to or involved in the incident. They do not concluded in their research that proximity of the witness might counter balance the high stress to aid memory (Gruneberg & Morris 1992).
In their study of a one hundred and twenty probationary police officers, Yuille, Davies, Gibling, Marxsen & Parker ((1994) as stated in Milne & Bull 1999) researched both these areas. Whilst putting the probationers in both stressful and non-stressful simulations, they concluded that stress decreased the quantity of accurate information but improved the accuracy and the resistance to decay over time.
Yuille & Cutshall ((1989) as stated in Milne & Bull 1999) go onto suggest that the accurate encoding and recalling of information may result from the subject rehearsing the scene in his or her mind, or recounting it to others so reinforcing it in their memory.
Howe, Courage & Peterson ((1994 as stated in Milne & Bull 1999) go further and say, the very stressful nature of the event will focus the subjects attention to core aspects of it. There may be internal feelings or external event factors, however, this narrowing of attention may assist with the memories being stored and remembered for longer.
This focusing, however, can be draw back as well as an aid to the encoding of information. At the scene of an armed robbery, there can be tendency to focus on a particular part of the event; this is called detail salience. In particular the presence of a weapon, especially a lethal weapon, can focus the witnesses attention so much that other detail such as description of the offenders are not paid attention to and therefore not encoded and stored.
In their experiment Loftus, Loftus & Messo ((1987 as stated in Gruneberg & Morris 1992) monitored the eye movements of two groups of subjects. Each group was shown one film; the films were almost identical except for one section of it. In the first film a man points a gun at a cashier and she hands over some money. In the second film instead of a gun, the man hands over a cheque and again the cashier hands over some money.
In the debriefs the group viewing the ?gun? scenario ?fixated? on the gun and were less able to recall other aspects of the film, such as descriptions, than the subjects who viewed the second scenario.
The application of these studies to aspects of policing, particularly investigative interviewing is important. Where quantity and quality of information is being judged, and where a victim has suffered from intense stress such as weapon focus, not to understand the impact these issues have on the nature of encoding is short sighted and limiting.
Despite the conflicting evidence I believe that stress in witnesses is a good indicator of the fragile nature of the memory in the instance of encoding.
Storage or Retention
For the second section of this essay, the area of post event information will be looked at prior to interviews. Within this, the question as to whether misleading information replaces (overwrites) or co-exists with the original information is discussed.
Once a memory has been encoded, it is not passive and it can be influenced. With the passing of time some of these memories can just be forgotten or fade, as the cues become weak. However, it is the potential for events to influence the original memory, that has caused much controversy amongst psychologists over the years.
Fruzzette, Toland, Teller & Loftus ((1992) as stated in Milne & Bull 1999) remind us that every one views a TBR event differently, and therefore will attend to different aspects of it. A witness to a road traffic accident may overhear another witness mention one particular aspect of this accident, and even if they had already attended to it themselves, the likelihood of them recalling that particular piece information post incident is increased. (Bekerian & Bowers 1983 as stated in Gruneberg & Morris 1992).
If the same witness to the accident overhears another witness recounting an aspect of the accident that they themselves did not attend to, then the chances of this new piece of information being recalled later is also increased.
So from the above it has been demonstrated that encoded facts can be enhanced by them being mentioned prior to interview. And we can see that new or misleading information that had not existed before, can take its place in the memory. Even the ability to recount accurate information can be affected by being given false or misleading information. Some studies demonstrated that the decrease in accurate information was as much as 30%-40%.
Research has also been undertaken regarding the impact of time and if the new information relates to central or peripheral aspects of the TBR event. Loftus, Miller & Burns ((1978) as state in Milne & Bull 1999) reported that the increased time delay between the supplementing of the misinformation and recall strengthened rather than weakened this new information.
Some researchers such as Dritsas & Hamilton 1977 (as stated in Gruneberg & Morris 1992) concluded that the strength of the memory might determine the extent to which it can be altered by any new misleading information. Additionally, the issue of central or peripheral preference, they concluded that aspects such as weapon focus ,which are central aspects, are less likely to be influenced that those on the peripheral.
Finally in this section the issue of whether the misleading or new information overwrites or co-exists with the original memory. As with most aspects of psychology opposing theories exists. The substitution hypothesis proposes that the ?new? (misleading) information does indeed overwrite the original memory in a permanent way. (Loftus 1979; Loftus & Ketcham 1991 as stated in Milne and Bull 1999). Zaragoza & Koshminder ((1989) as stated in Milne & Bull 1999) believed that the new detail does not make up part of the memory, but the ?effect occurs as a result of demand characteristics factors inherent in the testing situation ie.social pressure?.
In contrast to this theory McClosky & Zaragoza ((1985 as stated in Milne & Bull 1999) believe that the new and original memories can co-exists together. They surmise that given the correct retrieval conditions, the original memory was accessible. They suggest that instructing the subject to ignore the post-incident information could do this. However, other studies have demonstrated that even after having been given that instruction, subjects still continue to supply parts of the misleading information (Weingardt, Toland & Loftus 1994 as stated in Milne & Bull 1999). Even the causes of this type of misrepresentation of memories such as the source attribution theory can not fully explain this difficult but interesting field of the memory (Lindsay & Johnson 1989 as stated in Milne & Bull 1999).
Whichever theory a person subscribed to, it has now been well documented that false memories can occur at any stage following a TBR event, and these can be influenced in a number of ways. The importance for investigative interviewing is therefore evident. Even before the stage of recording a formal statement of interview has been reached, other witnesses and bystanders can begin the process of false memory paradigm.
By making officers aware of the impact misleading information clearly has on our memories, they can begin to protect and maintain its integrity. Here again I believe that the fragile nature of our memory can be seen and its implications highlighted.
In the third and final section of this essay the area of recovered memory syndrome will be discussed.
Although the issue of recovered or repressed memory has come to the forefront of the law, and indeed media, over the past few decades, its theory started as far back as Freud. The issue here is if a memory has been blocked, why? And is the method by which the memory is recovered quantifiable. For example some of the most sensational cases have resulted from repressed memories having been recovered during hypnosis or therapy. In the proceeding section how easy it is for misleading information to be introduced was discussed. This highlights the tenuous nature of memories ?recovered? after some time has elapsed.
Freud & Breuer ((1924) as stated in Rapaport 1942) when talking about hypnotic hypermnesia maintained;
?that a hysterical symptom could be traced back to an
original traumatic experience?
The implication is that the original memory is so traumatic that its existence is rejected or excluded by the conscious mind.
Hull ((1933) as stated in Rapaport 1942) tries to explain why childhood experiences long forgotten are recalled under hypnotic regression. He concludes that there are two hypotheses; Either the memory trace of a childhood memory is not particularly weaker than a normal memory, but that a trauma or emotional complex blocks or inhibits the recall somehow. The second hypothesis states that the recall is to do with the fact that a hypnotic trance automatically lowers the recall threshold to reveal these memories.
Since these early days of this kind of research, a greater understanding has developed and improved research methods. One of the initial problems with childhood/infantile amnesia is that it is well documented now that generally we have no memories before the age of three or four. (Fivush & Hammond 1990; Fivush, Pipe, Murachver & Reese 1997 as stated in Milne & Bull 1999).
Even in older subjects doubts as to the nature of repressed memories have been raised and not just in the UK. In the USA in 1990, George Franklin was convicted of the murder of a child twenty years before. The primary evidence rested on that his own daughter, Eileen, recalled that in 1969 when she was eight years old, witnessed her father killing her best friend. (Memon & Young Legal and Criminological Psychology page 131 and Hallanon, Park, Paul and Thomson, Time April 17 1995 page 56). However, in 1995 following an appeal, this conviction was overturned, but it acts an example of the impact so called repressed or recovered memories can have.
It is not that psychologists disbelieve that acts of abuse can occur or violent crime witnessed, but it is how the credibility of these memories can be ensured.
The view that ?recovered? memories are only available to be remembered at the appropriate time (i.e. in therapy) lacks scientific support according to Loftus 1993 (as stated in Milne & Bull 1999) and is a rare phenomena according to Read & Lindsay 1992 (as stated in Milne & Bull 1999). Thomson ((1995b) as stated in Milne & Bull 1999) suggested that suppression is the more likely explanation. On these occasions a subject chooses not to volunteer the information, so making the difference between the two clear.
Regardless of the theory one chooses to support, the existence of repressed or recovered memory is now well into the public domain and the legal system. There are several issues that relate it directly to its delicate nature and the implications for investigating officers. As with police officers, therapists and counsellors can be poorly trained and inexperienced when dealing with this kind of phenomena. By assisting a client to recover a repressed memory, making a suggestive remark or asking a leading question, a contribution can be made, even unwittingly, to the events that are then reported (Thomson 1995b as stated in Milne & Bull 1999).
The essence of the research into the syndrome, encompasses a wish to have an empathy with a victim of such a terrible crime. Whilst having the belief and expertise that if there were in fact a case to answer, then the recovery process goes to support the truth, not a miscarriage of justice.
The aim of this essay was to demonstrate the fragile nature of the memory, by using three examples that are linked in some way. The overall theme is that whilst we still do not understand everything there is to know about our memories, if indeed we ever will, we now know enough to make every effort in the criminal justice system to account for them.
To ignore all this evidence when conducting an investigation in to a crime, no matter what the circumstances is irresponsible at best, and negligent at worst. With the implementation of European Court Human Rights in October this year, it will be even more important that all agencies not just the police have a greater understanding of the fragile nature of memory.