Crime and Memory
Eyewitness testimony is paramount in determining the outcome of judicial proceedings. This makes sense considering how much we rely on our memory on a day-to-day basis. However, we’ve all forgotten where we parked the car, and we’ve all found ourselves walking into a room without remembering what our intentions were. While these are minor slip-ups, which we can write off, some of us may know what it’s like to be accused of saying or doing something we don’t believe we said or did. This might cause a bit of tension between or in groups of people, but being accused and convicted of a crime we did not commit is something that very few people have experienced.
According to Innocent Project – a non-profit organization that uses DNA testing to help exonerate wrongly convicted criminals – over 70% of 239 convictions based on eyewitness testimony have been overturned using genetic testing. (1) This makes us question why we use eyewitness testimony at all, and more importantly, makes us think about the accuracy of our own memories.
List of people exonerated using DNA testing
Click here if you would like to see part 2 of this documentary or here if you would like to view another documentary regarding crime and memory.
How the Brain Lies
As medical advancements and psychological research continues to progress, society (particularly the judicial system) is obligated to keep up, and we the people will eventually be left wondering: can you read my mind? While technology hasn’t progressed to mind-reading levels, scientists have made a few discoveries regarding the brain and what it looks like when someone is lying, even if they truly believe they are telling the truth. Researchers have discovered two different brain regions that may respond differently to true and false recognition. Apparently, our medial temporal lobe (MTL): parahippocampal gyrus shows greater activity during true recognition than false recognition. However, our hippocampus reacts equally to both. (2) Similar results have also been shown in other regions of the brain including the bilateral occipital cortices and the right parahippocampal gyrus. (3)
With that being said, science is still too far away to implement brain scanning lie detectors, and judges are far from accepting fMRIs as legitimate evidence for a crime. Hence, it’s at least safe to say that we can’t exactly read anyone’s mind yet. But if technology could help us detect our own lies, then one has to wonder what he or she would want to know or find out, if anything.
Why the Brain Lies
Although we get mad at ourselves for misplacing our keys, forgetting may be an adaptation rather than a design fault, and it may be a design fault that we actually want to have. After all, we don’t want or care to know where we parked the car last week. We need to know where we parked it today, and we don’t want to have to sift through all of our memories to do so. It’s efficient to have prioritized memories. However, when we forget we often question how or why this happens. From a cognitive point of view, neuroscientists tend to group causes of forgetting into three categories involving encoding, storage, and retrieval. Within each category there are many hypotheses that explain how forgetting can occur. Maybe we’re not in the correct setting to remember something, or perhaps similar memories are overlapping and are hard to tell apart. Whatever the case, the fact that our brain can drop the ball at so many levels should tell us something about the power of forgetting. In fact, sometimes people don’t want to know a particular piece of information, or they intentionally block out memories. (4)
Furthermore, even if forgetting is unintentional, and we fully believe in the accuracy of our memories, then why has criminology proven us wrong, and why do we tell different versions of the same story? If humans can make eyewitness errors regarding the most horrendous crimes and forget where their phones are, then who are we to not question everything in between? Humans do use past experiences to judge how the future will turn out, but if our past experiences can only be so accurate, then how do we know we’re making the right choices going forward? Looking back, it’s interesting to think about what we do and do not remember. However, the more important question is if we would want to remember everything when we do reminisce.
References
(1) Arkowitz, H., & Lilienfeld, S. O. (2009, January 8). Why Science Tells Us Not to Rely on Eyewitness Accounts. Retrieved from http://www.scientificamerican.com/article/do-the-eyes-have-it
(2) Cabeza, R., Rao, S. M., Wagner, A. D., Mayer, A. R., & Schacter, D. L. (2001). Can medial temporal lobe regions distinguish true from false? An event-related functional MRI study of veridical and illusory recognition memory. Proceedings of the National Academy of Sciences, 98(8), 4805-4810. doi:10.1073/pnas.081082698
(3) Okado, Y., & Stark, C. (2003). Neural processing associated with true and false memory retrieval. Cognitive, Affective, & Behavioral Neuroscience, 3(4), 323-334. doi:10.3758/cabn.3.4.323
(4) Ward, J. (2015). The remembering brain. In The student’s guide to cognitive neuroscience (3rd ed., pp. 195-230). Hove, East Sussex: Psychology Press.