13 D eyewitness testimony 2015 by rachel Hume

Face Recognition

grace_mccombie_parker — 2015-09-22 13:58:11 UTC

One problem with face recognition is that it can be affected
by unconscious transference. Ainsworth (1995) showed this when participants
were shown an article about an assault that contained 3 photos, 2 photos were
of the suspect whilst the third was of a “good Samaritan”. The participants
were split into 3 groups a week later, with group one being shown the suspect,
group 2 had the Good Samaritan included and the third group was random.
Ainsworth found that in the second group, 50% chose the Samaritan as the
suspect as they had a more familiar face. A difficulty with recognising faces
is shown by Ainsworth (1998), who found that unfamiliar faces are more
difficult to recognise as we have developed fewer mental images of them. This
causes difficulty as unfamiliar faces are more subjected to influence from
estimator and system variables. This shows that face recognition alone is not
wholly reliable as we tend to only see offenders once, however when it is
incorporated with other factors it could be more effective. A limitation of
eyewitness testimonies is technology. It’s been found by Pitchford et al (2010)
that traditional methods of facial construction has only led to a recognisable face
4.2% of the time. They found using the EvoFIT method, which is more global,
produced a recognisable face 24.5% of the time. This shows that we can’t rely
entirely on face recognition for eyewitness testimonies as they still are only
effective less than a ¼ of the time, even with the new EvoFIT method. Therefore, face recognition is a very significant limiting factor for eyewitness testimony as it has been proven that it isn't completely accurate. Studies have shown that the accuracy of eyewitness testimonies are not as accurate as desired, as there are also other factors that limit face recognition, such as the frequency of seeing a certain face, therefore making it a limiting factor of eyewitness testimonies and their accuracy.

What is the most significant factor limiting the accuracy of EWT???

thomas_salmon — 2015-09-22 13:59:24 UTC

Flashbulb memory

2015-09-23 08:27:18 UTC

Stress

2015-09-23 11:43:41 UTC

Yuille and Cutshall in 1986 conducted a study that
contradicted previous research and suggested that eye witness testimony is surprisingly
accurate. They found that witnesses of an armed robbery in Canada had
remarkably accurate memories of the stressful event which involved weapons. They
found accurate memories and recall even 18 months after the event had occurred
and misleading questions had no effect. Their research suggests that stress
doesn’t affect the accuracy of memory, however a weakness of
this study was that the witnesses who experienced the highest levels of stress
were actually closer to the event, and this may have helped with the accuracy
of their memory recall. A contrasting piece of research comes from Loftus’
study in 2013 on US military personnel. These men were trained to not give any
information despite use of torture against them. When asked to identify the
individual who carried out the torture 84% identified the wrong perpetrator
after being asked questions and shown a picture. Later, 27% reported to have
seen a weapon when there wasn’t one. This suggests that stress hinders memory instead
of helping it. Loftus’ study, however, is not representative of the general
population therefore the results cannot be directly applied to witnesses in
normal criminal cases. From the conflicting pieces of research it is difficult
to determine whether or not stress limits the accuracy of eye witness testimony
or whether it increases a person’s capacity to remember events. As there is a
lack of consistency in the studies, this suggests there is something wrong with
the effect of stress on a person’s ability to recall events.

reconstructive nature of memory / schema

rachellhume — 2015-09-23 12:16:56 UTC

The
reconstructive nature of our memory could be supported by factors such as
schemas, which alter encoded information to provide an inaccurate recall.
Schemas are cognitive phrasing, for example racial schemas may cause a person
to recall a black person committing the crime when the actual offender was white. Kleider et al (2007) showed
participants a man and a women performing stereotype-consistent then
stereotype-inconsistent actions and found during recall a reliance on schemas
to increase as memory faded over time (2 days). The results suggested that as
time increases, the effect of schemas increases. Particularly as eyewitness
recalls occur months after the incidents, there is a greater potential for
schemas to alter the accuracy of recall. However we can’t be certain either if
schemas played an effect in the study or whether people had poor memories,
particularly as this was a cognitive study meaning we can’t visually see the
cognitive functions of the brain, raising other [RH1] issues, as such, limiting
the validity of the overall approach. However it must be noted that Kleider also found that
visual scenes were typically well remembered. This raises questions about the
degree of effect that schemas have. Due to the distinctive nature of crime, a
person may remember and recall information more vividly than normal. Schemas
could therefore just ‘fill in the gaps’ to our memory rather than physically
change or interfere with our memory . Overman et al (2013) found significant
findings in light of this and to do with age. They found that older people who
have lower cognitive function than younger people had an increased schema-based
processing in recalling a crime scene. This again supports the idea that our
cognition relies on schemas like a leaning post to fill in the gaps where
information is missing. Particularly as older
people have a significant decrease in cognitive function, schemas may have a
significant function in aiding recall in older people. The evidence
above also suggests that our cognition uses schemas to ‘fill in the gaps’ to
our memory so it is unlikely that an accurate memory will be altered by schemas

[RH1]This
may limit the validity of cognitive approaches

FlashBulb

2015-09-24 08:37:06 UTC

In contrast to the evidence that suggests eyewitness
testimony is inaccurate, the idea of flashbulb memory shows that under certain
conditions we can recall in accurate detail. Flashbulb memories are distinctly
vivid, long-lasting memories of a personal circumstance usually caused by
emotional arousal. It is this emotion that increases the ability to recall the
details of a specific event that may improve the accuracy of eyewitness
testimony. Davidson, Cook and Glisky looked at everyday memories compared to
the memories of the 9/11 World Trade Centre attack, a year after the attack
occurred. There was a high, positive correlation between the initial and
subsequent recollection of the 9/11 attack. This suggested that events that
evoke a strong emotional response create accurate memories and therefore in
this situation eyewitness testimonies are accurate. Davidson, Cook and Glisky
used both old and young people and the results suggested that memory retention
doesn’t change with age. A strength of this study is that it was done a year
after the event happened therefore the memory would have had to be stored for a
long time. It had high ecological validity but a lack of control. A limitation
of this study is that it only found a correlation not necessarily a causation
of the improved memory. Brown and Kulik (1977) also argued that we all have a
specific biological memory mechanism triggered by significant, often unexpected
and emotional events or experiences. A contrasting piece of research was conducted by Bohannon III, John Neil in 1988, he looked into the flashbulb memories for the Challenger Space Shuttle disaster who interviewed participants close after the event and 8 months after. Few subjects had flash bulb memories of the disaster, after eight months. Less than
35% had a detailed memories of the event suggesting that memory is inaccurate
and therefore eyewitness testimonies are inaccurate. However, there could have
been individual differences of reaction to the event therefore some may not
have been emotionally affected by the event meaning their memories surrounding
the disaster are no flashbulb memories. Flashbulb memories are not necessarily accurate in evert respect, but they demonstrate that the emotional content of an event can greatly enhance the strength of the memory formed. This increases the accuracy of an eyewitness
testimony if the event experienced was particularly emotionally poignant. However,
some studies suggest that flashbulb memory decays over time suggesting it isn’t
accurate a long time after the event has occurred. The inconsistency of this
phenomenon means it cannot be assumed that an eyewitness’s account is accurate.

Weapon focus

2015-09-24 08:51:35 UTC

Stress (re done)

2015-09-24 08:59:53 UTC

In 1908 Yerkes and Dodson completed research into the effect of stress and arousal on a person’s ability to perform tasks such as memory. They believed that a person’s memory will be improved by stress/arousal up a certain point where it reaches an optimum level. They believe that any excess levels of stress or arousal from this point onwards would lead to a person’s memory recall decreasing in accuracy. This is important for Eyewitness testimonies as you could say that a person directly involved in a crime would have too higher levels of stress and their ability to recall information would drop significantly. However there is another problem with this theory as everybody will be effected differently by stress and you cannot tell some people there recollection of events could be used in court and somebody else that they cannot. Yuille and Cutshall in 1986 conducted a study that contradicted previous research and suggested that eye witness testimony is surprisingly accurate. They found that witnesses of an armed robbery in Canada had remarkably accurate memories of the stressful event which involved weapons. They found accurate memories and recall even 18 months after the event had occurred and misleading questions had no effect. Their research suggests that stress doesn’t affect the accuracy of memory, however a weakness of this study was that the witnesses who experienced the highest levels of stress were actually closer to the event, and this may have helped with the accuracy of their memory recall. A contrasting piece of research comes from Loftus’ study in 2013 on US military personnel. These men were trained to not give any information despite use of torture against them. When asked to identify the individual who carried out the torture 84% identified the wrong perpetrator after being asked questions and shown a picture. Later, 27% reported to have seen a weapon when there wasn’t one. This suggests that stress hinders memory instead of helping it. Loftus’ study, however, is not representative of the general population therefore the results cannot be directly applied to witnesses in normal criminal cases. As both of these pieces of research are biological we can safely say that they are objective and scientific providing us with quantitative data that we can compare and contrast. However, as it is the Biological approach, we can say that this research is nomothetic and reductionist in theory as it assumes that everybody is the same in terms of the way they are made up. From these conflicting pieces of research it is difficult to determine whether or not stress limits the accuracy of eye witness testimony or whether it increases a person’s capacity to remember events. As there is a lack of consistency in the studies, this suggests there is something unpredictable with research on the effect of stress on a person’s ability to recall events, with no clear answer being discovered.