Ikier, S., Tekcan, A.I., Guelgoez, S., & Kuentay, A. (2003). Whose life is it anyway? Adoption of each other’s autobiographical memories by twins. Applied Cognitive Psychology, 17, 237-247.
Abe, N., et al. (2008). Neural correlates of true memory, false memory, and deception. Cerebral Cortex, 18, 2811-2819
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The left side of the brain confabulates our memories and ability to recall those memories. The two readings by Ikier and Abe attempt to discover the regions in the brain that confabulation occur and its different types. Ikier reveals three testing modes (true, deception and false memory) to locate which parts of our brain are responsible for correct and false recognition. However the article lacked a deep explanation defining the difference between false memory and deception. I don’t actually think they were able to test whether the subjects were confabulating or pretending to confabulate. This requires some sort of question and answer process where the subject can respond with, “I know” or “I don’t know” as mentioned in the background of the article. Instead, they flashed words for two seconds at a time recalling new and true targets of a memory. I guess I’m a bit confused as to how that works. I understand if it’s a true target and subjects used their index finger to indicate it being a true, but if it’s a false target how can you differentiate between false memory and deception? They seem like two different categories with one answer in this study.
Abe who tests the differences in twins and siblings takes the confabulation idea further. In sum, Abe found little differences in twins and slight differences between siblings. I think it’s important to note in Abe’s discussion how twins are treated almost the same throughout their childhood which would explain the little or no difference in their experiences. Twins are treated like a unit rather than individuals most of the time compared to siblings who’s ages are different. I think it would be interesting to take a look at collective memories that we share with others like Abe mentioned between best friends, couples, etc. that could give us a better clue on recalling our memories correctly. The experiences that we go through with our friends, marital spouses, etc would definitely be different because we interpret things differently. Why should twins be the exception because they were raised in the same manner? Twins also don’t think the same way, they have noticeable differences in the way they perceive things and have different brain sizes. This alone proves that memories aren’t identical.
In the study by Ikier, et al (2003) entitled Whose Life is it Anyway? Adoption of Each Other’s Autobiographical Memories By Twins, researchers studied the disputed memories between monozygotic (idential) twins, dizygotic (fraternal) twins, and same-sex pairs of siblings. Each individual twin or sibling was interviewed and asked to describe both personal memories and any memories in which the protagonist was uncertain, and to rate these memories on importance, the amount of detailed imagery, and how often it was discussed with the other twin. I was especially interested in how frequently the disputed memory was discussed between the twins—perhaps frequent rehearsal of the memory would make each person more convinced they had been the one to experience it, not their twin. Alternatively, maybe whichever twin was most emphatic about the memory would convince the other one it had occurred to them, regardless of the truth. Ikier, et al found that disputed memories often took place very early in childhood, which corresponds with the idea of infantile amnesia. Additionally, these disputed memories were not rated as important or detailed, nor where they discussed frequently with the other twin. Identical twins had the highest rating of disputed memories, but fraternal twins had slightly more disputed memories than the non-twin siblings.
Since the disputed memories in question were not important events that happened in very early childhood, this partially explains why the protagonist of the memory remained ambiguous. The researchers also theorized that perhaps the parents were themselves unsure about which twin the event in question had happened to, and thus could have been rehearsing the same memory with both. Since monozygotic twins are often similar in temperment and clearly physically identical, it wouldn’t be difficult for parents to be unsure, and even more likely for grandparents to be unsure of which twin had experienced which event. This reminded me of a previous study we’ve read for class, Harpaz-Rotem and Hirst’s (2005) study on low-elaborative and high-elaborative mothers, and how the parents’ efforts have a significant effect on recall of early childhood events. As an only child, the phemnomen of disputed memory is alien to me, but I thought the study results made intuitive sense—distant memories of early childhood can be difficult to access, and being an identical twins must complicate that even further.
Abe’s study of the neural correlated of true memory, false memory, and deception found that lying, whether pretending to know or not to know, activates the left prefrontal cortex, while false memories are associated with right hippocampal activation. These fMRI images, coupled with findings of longer reaction time in deceptive responses, indicate that lying requires greater higher-order cognitive processes than the retrieval of illusory memories. This makes intuitive sense, as one is generally aware of their own deception, whereas a mistake or a false/misinformed belief may be expressed with complete confidence and is not generally taxing on a cognitive level. What I’m interested in knowing is whether over time synthesis would occur and a shift in neuronal activity would develop. I guess I’m proposing a cognitive rational for ‘repression.’ Rather than repression being due to dissociation, perhaps it is the evolution of a cognitive process (deception,) into a memory oriented one governed by the hippocampus, so over time one could form a false memory out of deception.
In “Whose Life Is It Anyway? Adoption of Each Other’s Autobiographical Memories by Twins,” I found it particularly interesting that “the relative insignificance of the events contribute to the process of adopting others’ memories.” I want to know more about this. My first thought is that the most significant events are the truest ones for the reason that one’s real experience, the real encoding of it, adds to the experience’s importance. But I wonder why this is so. I can relate this question to the other reading, “Neural Correlates of True Memory, False Memory, and Deception.” This study predicts “that the regions responsible for auditory processing would be preferentially active during true versus false recognition due to sensory reactivation, because true memories engage perceptual encoding processes that are presumably not involved in the creation of false memories.” It makes sense that true memories would activate the regions of the brain that are responsible for auditory processing because auditory processing is something that seems to mainly take place during encoding, but I wonder if such physical resonance of an event also adds to the significance of the true memory. I come to this possibility because the existence of encoding—or lack there of— is one difference that exists between true and false memories. Therefore, the physical encoding of a memory and the memory’s overall significance may correlate.
But if this is so, I wonder what it is about the physicality of a memory’s encoding that adds to the significance of that memory. The most important memories seem to be the memories that help to shape one’s identity, their sense of self. Therefore, I wonder what role the encoding of the memory plays in the incorporation of that memory into one’s identity. It seems it would play a crucial one. Even though memories are reconstructed and get integrated into one’s self in various ways over time, the initial encoding of the memory must have some effect on the subsequent integration of it into one’s identity.
It seems that once one’s self already becomes invested in that memory, particularly by encoding it, that that memory contains more significance. The trueness of it seems to lie in its encoding, and thus a different amount—or different sort—of resonance in the remember exists than if the process of encoding hadn’t taken place. I want to know more about this, to know more about the role that the physicality of encoding plays in one’s sense of self, and thus the significance of their memories.
In the study of false memory, it seems increasingly imperative that studies such as Abe’s “Neural Correlates of True Memory, False Memory, and Deception” examine the distinction between memory impairment and purposeful memory distortion (lying) on a neurobiological level.
Although these sorts of studies are still in their beginnings, the repercussions of false memories have proved to be far reaching- from family destroying false allegations to issues of eyewitness testimony. Although preliminary, I believe Abe’s work is incredibly important in a “real life” setting.
In all my studies of false memory (as this is my literature review topic) there were a few things that stood out remarkably to me in this piece. The first thing was the discussion of neurological proof that the same methods are used in encoding information as well as recalling it. This seems to have been proven in numerous ways- studies have shown (I don’t have a particular reference here…) that memories are recalled typically in the same way that they are encoded. If there is a memory was particularly sensory (vivid imagery, etc.) than it will most likely be recalled with the same vividness and appeal to whichever sense was most integral in its encoding. I think the fact that this can now be seen literally with brain functions will be important to continuation of memory research.
In regards to distorting memory, I think it is important that the article shows the neurological distinction between purposeful deception and false memory. This is important, but also a problem, with methods of distinguishing false memory. If technology became advanced enough to scan the brain of every eyewitness in order to determine their validity, although you might be able to tell if they were lying, there is no way to distinguish if their memory is true or not. I believe this has to do with Roedigger and McDermott’s “remember v. know” experiment, which Abe’s fMRI study was partially based on. This experiment showed (when using word lists) that 72% of subjects “remembered” (had an episodic memory) hearing words that weren’t present, as opposed to “know” (semantic knowledge of the word). In this way, it is understandable that there is no biological distinction either. Subjects literally remembered hearing the non-present word, which is to say that false memories can truly deceive the brain.
The most interesting aspect of the study, I thought, was when the fMRI revealed that although the right anterior hippocampus was activated during a false memory (recalling a non-presented word), the same language components that exist in true recall were not present. I find this fascinating and also think it may relate to Nelson and Fivush’s language development hypothesis. The fact that false memories lack verbal recall also implies what I stated earlier about encoding and recall- the false memory was never actually encoded verbally, and thus when recalled, the verbal component would be nonexistent. This also proves the importance of language when forming a true autobiographical memory- literally the language component is neurologically necessary for proper encoding and subsequent recall.
What are the consequences if lying requires greater higher-order cognitive processes than telling the truth? At this moment polygraphs, commonly called "lie detectors," are instruments that monitor a person's physiological reactions. As a person is questioned about a certain event or incident, the examiner looks to see how the person's heart rate, blood pressure, respiratory rate and electro-dermal activity (sweatiness, in this case of the fingers) change in comparison to normal levels. Fluctuations may indicate that person is being deceptive, but exam results are open to interpretation by the examiner. I restate all this because Abe’s study made me think about how our brain images might expose a lie. In the future, with better knowledge of the brain and brain-imaging technology, we might have the ability to gage whether a person is lying by pinpointing in a particular moment whether they are using their higher-order cognitive processes or not. The consequences of this would be huge, immeasurable, scary. “You can’t handle the truth!” (A Few Good Men). I believe that we as a society cannot handle this type of “truth.”
http://www.youtube.com/watch?v=5j2F4VcBmeo
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