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by Lauren Lin Déjà vu is the hard to describe and sometimes eerie feeling that you’ve already experienced something before, despite knowing that you’re in a new situation. For example, you could feel as though you’ve already watched a certain movie, even though you can’t remember when, and you objectively think that it should be the first time that you’ve seen it. Over the years, people have attributed this phenomenon to a variety of causes, ranging from reincarnation, to glitches in our memory, to supernatural theories.
While some of these explanations are interesting to think about, many lack scientific evidence. However, despite the numerous scientists who research déjà vu, there hasn’t been a theory that everyone can seem to agree on. Some research has indicated that there may be a connection between our memory system and the feeling of déjà vu. Anne M. Cleary, a psychologist at Colorado State University, investigated the relationship between déjà vu and our recognition memory—the type of memory that alerts us that we have already experienced what we are currently going through. Recognition memory has two subdivisions: recollection and familiarity. Recollection-based recognition is when we can explicitly remember when in the past we have experienced something. For example, if you went and saw the new Star Wars movie for the second time, you’d experience recollection-based recognition because you would know that it’s your second time seeing the movie. Familiarity recognition is when we are less sure about why we seem to recognize a situation, which is why it is thought to be responsible for déjà vu. Cleary performed a series of experiments that induced déjà vu, and discovered that when small fragments of memories (such as geometric shapes) overlap with a new experience, it may create the false impression that you’ve seen or done something before. On the other hand, Akira O’Connor and his research team at the University of St. Andrews used a word task to elicit déjà vu and to measure the brain activity of 21 volunteers using fMRI. O’Connor discovered that areas of the brain usually associated with memories were inactive during the test and that déjà vu may be mediated by frontal areas of the brain that play a role in decision making, which were active. Therefore, déjà vu may not be a consequence of poor memory. Rather, O’Connor hypothesized that déjà vu comes from the brain realizing that there has been a mistake in the recall process, and so it might signify that your memory checking system is functioning well. This is consistent with the fact that younger people experience déjà vu more frequently and that its occurrence decreases as age increases, since memory checking abilities deteriorate as people grow older. A case that seems to be promising for further study is that of a 23-year-old British man who appears to have “chronic déjà vu.” The man reported that he felt as though he was reliving experiences for extended periods of time, and his condition became so disruptive that he stopped watching television, listening to the radio, and reading newspapers. He was otherwise healthy, and his brain scan results didn’t suggest any abnormalities, which led researchers to believe that his chronic déjà vu had a psychological cause. The man used to have depression and anxiety, but so far no conclusions can be made about the reason behind his condition. However, déjà vu has been found to be connected to certain psychoneurological disorders, like temporal lobe epilepsy. Those who have temporal lobe epilepsy tend to experience mood and memory difficulties and frequently experience déjà vu during aura (subjective perceptions that occur around the same time as seizures and sometimes serve as warning that a seizure is about to happen). Researchers are working hard to gain a better understanding of déjà vu, but its cause remains elusive for now. Will we be able to find out why déjà vu happens? Only time will tell, and you’ve definitely heard that before.
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by Omri NachmaniSeeing is believing. But in the case of school textbooks and PowerPoint presentations, seeing becomes much more passive and disengaging. If you’re lucky enough to possess a powerful imagination, you could make any lecture - whether it’s about the powerhouse of the cell or the American Civil War - just as realistic as if you were seeing it for yourself. For the rest of us, a little push would be well appreciated.. That’s why, when I received a piece of cardboard as a Christmas gift, I was soon unable to put it down. This Google Cardboard “device”, paired with your run-of-the-mill smartphone, turns into a fully immersive virtual reality headset. Thus began my year-long obsession with this up and coming technological revolution.
by Alana Duffy Many of us have watched an episode or two of Criminal Minds and wondered to ourselves, “how can someone be so messed up? What could turn a normal human being into a heartless, psychopathic monster?” Most psychopaths in mainstream media have usually been through some sort of traumatic childhood event. However, most Law and Order type programming often ignores the nature side of the Nature vs. Nurture debate. Environment and life experiences are suggested to play a large role in the creation of a psychopath, but so do genetics and physical abnormalities of the brain.
Most of us experience varying degrees of stress at some point or another, and how we react to these events is partially regulated by a series of genetic predispositions. One explanation is the Diathesis-Stress model, which suggests that people inherit certain stress responses. The term ‘diathesis’ represents these genetically inherited tendencies. However, these behaviours don’t become prominent until a certain environmental trigger occurs. This suggests that someone could be a psychopath and not know it until they’ve been triggered by a certain stressful event. Exams aren’t typically a stressor involved in psychopathy, but I’d be lying if I said I’ve never made a joke about killing the person sitting across from me because they’ve been yelling on the phone for 45 minutes. More commonly, triggers amongst psychopaths include physical or emotional neglect, or general familial instability during childhood. But here’s the thing: not everyone who experiences one or more of these childhood stressors becomes a raging murderer. This illustrates that genes have a large role in our emotional reactions to a situation. Thankfully the particular genotype (MAOA-L) found in psychopaths seems to be relatively rare. But what exactly is MAOA-L, and why is it important? This gene is a low-expression variant of the MAOA (Monoamine Oxidase A) gene that has been linked to an increased risk of violent and aggressive behaviour. Monoamine Oxidase A is an enzyme responsible for breaking down monoamine neurotransmitters such as dopamine and epinephrine (more commonly known as adrenaline). A mutation in the MAOA gene leads to a deficiency of Monoamine Oxidase A, which in turn causes an excess of monoamine transmitters. This contributes to the impulsive and violent behavior of psychopaths. Additionally, genes regulate the physical development of our brains. The limbic system, an area of the brain involved in memory formation and emotional processing, is often underdeveloped in psychopaths. We gather new life experiences through our senses, and this sensory input travels to the hippocampus (our memory processing and storage centre) where it is consolidated and compared with our previous experiences. The amygdala, a structure involved in emotional responses, then decides how we should feel about the situation based on past events. Considering this, it is unsurprising to learn that neuro-imaging studies show reduced blood flow (an indicator of brain activity) to the hippocampus and amygdala - psychopaths don’t process experiences the same way “normal” people do. Therefore, they don’t always have the proper emotional response to a situation. Essentially, they don’t make the necessary connections to learn from previous mistakes and thus don’t feel guilty about their actions. Another area of interest in the psychopathic brain is the prefrontal cortex of the frontal lobe of the brain. The frontal lobe is responsible for motor function, problem solving, memory, language, judgement, social behavior, and a host of other things. In particular, the prefrontal cortex is in charge of forward planning, prediction of outcomes, expectation processing, and social control. Once the amygdala has processed memory experience and has decided on an appropriate (or highly irrational) emotional response, this idea travels to the prefrontal cortex, where it is then decided whether the action is actually a good idea. You probably know where I’m going with this. The prefrontal cortex is yet another area in the psychopathic brain that doesn’t work the way it’s supposed to. Lesions in this area are typically associated with uninhibited behavior, and in psychopaths there is an overall reduction in metabolism and activity here. The characteristic impulsiveness and lack of concern for consequences seen in psychopaths is largely due to prefrontal cortex dysfunction. Remember the Stauffer Library example mentioned earlier, about someone talking loudly on the phone? Most of us are neurologically developed enough to know that murder is an irrational and immoral response to any situation. Additionally, the consequences are too great. Orange Is The New Black is a great show, but jail is still very unappealing. I don’t know about you, but personally all I ever do is give the person dirty looks, or maybe get annoyed enough to actually say something. However, a true psychopath may not make those connections. They process the world differently and cannot assign rational emotional responses to their experiences. They likely wouldn’t consider or care about the repercussions of their actions. So, the next time you complain to your friends about the “psycho” who keeps quadruple-texting you, take a moment to be thankful that you are over-exaggerating. |
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