[Music] eyewitnesses are trusted to give evidence in court that could result in convictions but how accurate is its testimony and what are the factors that make outwards test me more or less accurate in this video we're going to cover the effects of misleading information post event discussion and anxiety to examine how accurate eyewitness testimony really is psycboost.com over 170 videos to help you with your qualification and patreon supporters can access bonus resources tutorial videos and the discord channel misleading information before jumping into misleading information i need to give you a little background information on the ideas of this guy bartlett baller argued that memories are not accurate snapshots of the past that are carefully stored away in our mind no butler argued that our memories are reconstructive and butler developed an idea called a schema and these are packages of information that we use to understand the world around us now schemas are a really important part of psychology and come up again and again in this course for a more detailed explanation of schemas jump over to my cognitive psychology video maybe after this one when applied to memory though we could say that schemas reflect our attitudes and stereotypes and we use schemas to construct our memories so this is a problem for eyewitness testimony if memory is reconstructive then it's not accurate in its reconstruction it's changed and will produce errors false memories are bartlett called confabulations this explains how misleading information influences memory this can include leading questions so the words that i use to ask a question can imply a certain response and this influences the memory that someone reports and there are two possibilities one that the actual memory does change it replaces the old memory completely and we'll call this substitution bias but there is a second possibility the memory doesn't actually change but there's an emotional pressure that alters your response and we would call that response bias before we come to the research i want to define post-event discussion this is the contamination of eyewitness testimony with another witness's memory reducing accuracy when witnesses discuss what they've seen we find that the testimony alters to match the accounts of other witnesses and this is called memory conformity have a look at this clip how fast were the cars traveling when they smashed into each other okay what was it about how i asked that question that we would say is leading of course it's the word smashed a researcher called loftus showed traffic accident clips like that one to participants and that's how fast were the cars going when they hit each other changing the verb hit into smashed collided bumped and contacted the results showed that the more extreme the verb the faster the participants guessed the car was traveling contacted was a slower speed at 31.8 miles per hour and smashed with the fastest at 40.5 now this does suggest that misleading information in the form of leading questions can influence a recall of eyewitness testimony in a second study one week after being asked if the cars smashed or hit each other the participants were invited back and completed a follow-up questionnaire one of the questions was did you see any broken glass now more than twice as many participants said they'd seen broken glass in the smash condition now it's been a week since the first part of the study and it's likely the participants might not even remember that the word smashed or hit was originally used i would argue that this is a real change in the memory so substitution bias not just response bias now i've already discussed post event discussion that witnesses change their recall to be in line with other witnesses and here's an interesting research study showing the effect gabba showed videos of the same crime to pairs of participants but each member of the pair was shown a different video showing the crime from separate perspectives now if they were allowed to discuss what they'd seen with the other witness when interviewed later alone 71 percent of the participants would include items they hadn't seen in their video but head in the discussion and this is a demonstration of memory conformity that witnesses will change their recall to match other witnesses anxiety another factor that affects eyewitness testimony is anxiety a quick definition of anxiety is is a mental state of arousal you tense up and you feel overly cautious there are biological factors too like an increased heart rate now it seems a fair point that anxiety may have a role to play in the accuracy of eyewitness testimony which is important as in many situations that use eyewitness testimony witnesses are recalling anxious situations like violent crimes but none of the lab-based research we've looked at so far makes the participants anxious so maybe those studies lack validity there are a few suggestions of how anxiety affects recall some psychologists argue anxiety decreases recall people are so anxious that they become distracted not paying attention so they can't accurate recall later one aspect of this theory is the weapon focus effect the eyewitness is so focused on the gun or the knife that they don't look at the face of the criminal on the other hand there are psychologists who argue that high levels of anxiety actually increase recall the anxiety makes a witness more alert to the situation around them as well as a stronger emotion making a stronger memory but there is a third theory that brings both these two opposite ideas together the jerks dodson law of arousal this theory suggests that with very low anxiety recall is low because a witness isn't paying attention as anxiety increases the witness becomes more aware and focused so recall improves but a certain point the witness becomes too anxious and stressed and in that panic loses concentration resulting in less accurate eyewitness testimony as you can see we can draw a graph to represent the accuracy of eyewitness testimony with low medium and high anxiety the classic research on anxiety and eyewitness testimony was conducted by johnson and scott in this study unaware or we can call them naive participants sat outside a lab waiting to take part in a study but little did they know the study had already started the participants either heard a conversation about equipment failure and a man walking out with greasy hands and a pen or a hostile conversation breaking glass and furniture being knocked over a man walked out but this time with a knife and his hand covered in blood when asked to identify the man from 50 photographs 49 of the participants could identify the man with a pen but only 33 could identify the man with the knife well this study did cause anxiety and the results suggest that anxiety caused by the knife resulted in weapon focus and less accurate eyewitness testimony now we could certainly criticize this as still being a lab study but we do see a similar effect in a field study by peters who showed that recall was worse for identifying a nurse who gave an injection to the participant than for a researcher who was also in the room this suggests weapon focus for the syringe reduced accuracy but there is of course counter evidence thirteen witnesses to a real life deadly shooting were interviewed by researchers uvul and kutchel four months after the event the researchers found recall to be highly accurate the participants managed to resist leading questions and high levels of stress didn't seem to impact the accuracy of eyewitness recall some of the most accurate recall was from the people who would have been the most dressed as they were closest to the shooting additional evaluations we can finish by exploring a range of additional evaluations firstly there's been real-world applications of research on the limitations of eyewitness testimony in particular the development of the cognitive interview the cognitive interview is the subject of the next memory video but all of the lab-based eyewitness studies can be criticized as having low validity because of the lack of consequences incorrect eyewitness testimony in a courtroom under oath can lead to wrongful convictions and this may lead to more accurate eyewitness testimony lab studies also suffer from demand characteristics with participants memories not actually changing but perhaps picking up on the language used and guessing a response that they think the researcher wants to hear this could be a problem especially in research looking at leading questions and finally much of the research investigating anxiety could be unethical researchers have a duty not to harm participants and to gain informed consent research like johnson and scott needs to break both of these guidelines and asking participants to recall the details of a murder they've witnessed could be a traumatic experience have a go at this real exam question on factors affecting eyewitness testimony if you're a psych boost patron at the norm level and above you can access the tutorial on psycboost.com and in it i'll talk you through a model answer for this question and some general tips for everyone else don't forget to like and subscribe so you don't miss the videos released right up to your exams and i'll see you in the next cycles video improving the accuracy of eyewitness testimony you