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everyday tasks, they relied on their residual arm less than expected but instead, exhibited increased use of their face, lower limbs, and other objects to compensate for their missing hand’s function. The functional MRI data showed this was BY JULIA SUNSTRUM related to increased blood flow to the missing-hand territory during the movements of other, originally unexpected and sometimes quite ave you ever been overcome by the distant, body parts. overwhelming sensation that you have experienced this exact situation before? Remapping in “the missing hand This is the phenomenon of déjà vu – the territory was selective to those body two-fold feeling that something is familiar parts used for compensatory purposes”, but the knowledge that it shouldn’t be. said the authors. “The typical hand territory may not necessarily represent Most people, approximately 2/3rds, the hand per se, but rather any other report experiencing the fleeting sense of body part that can mimic the missing déjà vu, which is French for “already hand’s functionality.” seen”. Interestingly, it is most common
EPILEPSY PROVIDES INSIGHT INTO DÉJÀ VU PHENOMENON
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This idea may be groundbreaking because it changes the subtle misunderstanding of the homunculus as “body part” specific to “function” specific. Instead of brain regions representing individual body parts like the lip, hands, and leg, they represent specific types of functional movements. With this new understanding of body representations in the brain, treatments that are used for phantom limb pain like the mirror box, which uses a mirrored illusion to trick the brain into believing the residual limb is actually the amputated limb, can be optimized by focusing on specific movements, and appropriate therapies can be developed to maximize the ability of the residual limb territory to re-wire itself.
between the ages of 15-25 and is more likely to occur during times of stress or exhaustion. Despite the high prevalence, scientists do not understand the underlying cause. The feeling itself is hard to study because spontaneous déjà vu cannot be induced or created by researchers.
So, what causes this feeling? Research suggests it may be the result of a momentary hiccup in a basic memory process. The brain is constantly scanning the environment to identify familiar or new things. This process, termed recognition memory, depends on the brain’s ability to recognize something stored in our memory. Recognition memory is an essential function that helps us navigate and interact with the world. Recognition happens in two ways: familiarity, where we have a feeling that we have seen or experienced something before but might not remember when or
SOCIETY OF NEUROSCIENCE GRADUATE STUDENTS
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