The Influence of Emotions and Memory - Research Paper Example

The Influence of Emotions and Memory Interplay between emotions and memories is a significant survival function. It is observed across many animals because survival is an object of living. Memory is that part of cognitive ability that enables an animal to use past experiences to guide future thoughts and actions, while emotions determine which events and experiences threaten its survival (Phelps and Sharot, 2008, p. 151). For example, among younger adults, they detect threatening stimuli much more quickly than other types of stimuli (Mather and Knight, 2006, p. P54). Understandably, the connection between emotions and memories permits one to remember dangerous situations and to avoid them in the future (Phelps and Sharot, 2008, p. 151). Scientifically, studies on emotions and memory touched on the amygdalo-hippocampal junction, aside from other brain structures. Individually, amygdala processes emotions. Through it, a seemingly neutral stimulus elicits negative or positive emotion when associated with a similarly negative or positive event. On the other hand, hippocampus allows a person to store events and experiences at will. Part of their normal function includes their interaction with each other. This interaction is the reason why memories associated with emotions are more vivid and more persistent than others which do not bring forth emotions (Phelps, 2004, p. 198). However, this is also the reason why these memories are susceptible to have inaccurate details (Phelps & Sharot, 2008, p. 147). CREATING MEMORIES WITH EMOTIONS There are three major steps in creating memories, (1) perception, (2) retention, and (3) retrieval. Each involves a set of mechanisms different from the other two, and as such is affected by factors in a different manner. What makes the creation of memories more complicated are the types of memories one must process daily throughout a lifetime. The first type is retrospective memory. It involves remembering information or events from the past, as when one retells a friend what happened yesterday, or when one thinks about what to write on a movie review. The other type is prospective memory, which involves encoding, retaining, and executing intended actions. When one plans tasks, such as paying the bills, remembering to meet a doctor’s appointment, and feeding the dogs, he/she uses prospective memory (Kliegel & Jager, 2006, p. 1). Because of the very different nature of these types of memory, most certainly their processing are different as well. 1. Sensory perception and attention Differences between prospective and retrospective memory are already apparent in the first step of memory processing, which is sensory perception. Because of the circumstances in which prospective memories are used, sensory perception and attention for creating them are much more needed, and the brain is implored to put attention to receiving as much information, and as such may need cortical mediation. For retrospective memories, on the other hand, since they are not as important as the other type, because the attention used for their perception is usually what is made available. What makes it easier for making prospective memories is that, because what is needed to be retained is already defined, the attention one gives to gather the needed information is more or less enough. On the other hand, because retrospective memories usually involve gathering a variety of details, the attention one allots is usually not enough for all details to be gathered (Kliegel & Jager, 2006, p. 1). When a stimulus is encountered for the first time, the attention available for its processing is a telling factor on how well the stimulus activates the sensory processor (Phelps, 2004, p. 199). This attention is important in the subsequent storage of the memory of stimulus encounter. Both hippocampus and amygdala affect attention allocation, albeit independently (Glascher, Rose and Buschel, 2007, p. 4371). The amount of attention one can apportion to a stimulus is influenced by the intensity of emotions brought out by the encounter. When a sensory organ sends signals to sensory cortical processing regions upon negative stimulation, signals are transmitted to the amygdala. After the amygdala has accorded emotions on the stimulus it will send back signals to the sensory cortex to increase attention to the stimulus (Phelps, 2004, p. 199). When a stimulus has poor quality, such as a low resolution picture, it elicits insignificant amygdala activation for both neutral and negative pictures. But when the stimulus is of high quality, amygdala activation significantly differs between neutral and negative stimuli, with negative stimulus activating the sensory processor more than the neutral ones can (Glascher, Rose and Buschel, 2007, p. 4371). Glascher, Rose and Buschel (2007, p. 4366) observed that a high load of stress on hippocampus competes for attention that could otherwise be allotted for stimulus perception. However, it seems to affect a different mechanism from the one used by amygdala. Still, the amygdala can override hippocampal activity, when a high quality, negative stimulus is presented (Glascher, Rose and Buschel, 2007, p. 4371). The superiority of amygdala was noted by Mather and Knight (2006, p. P54). Among younger adults, they detect threatening stimuli much more quickly than other types of stimuli because the process through which threat is detected and processed is an automatic response independent of emotion-regulation by cognitive control. Still, this is in support of using memory and emotion interplay primarily for the individual’s survival. 2. Memory consolidation and retention After stimulus perception comes consolidation and retention. Memory consolidation means that how a memory is stored becomes modified over time so that their retention is less dependent on the brain structures that allowed their early retention, such as hippocampus. Consolidation also allows memories to be less susceptible to disruptive forces, so that it can be retained in the brain (Abraham, 2006, p. 6). The role of hippocampus in the early memory retention allows the intervention of amygdale in this step of memory processing. All memories are encoded by the hippocampus. However, the relatively long period between their encoding and storage opens these memories to disruptive forces that prevent their storage. Many studies support the hypothesis that this period provides a window for an emotional reaction. Included in this reaction is the release of hormones, which influence hippocampal retention and consolidation (Phelps, 2004, p. 199). This is supported by Kleinsmith and Kaplan (1963) when they observed that emotionally arousing words are recalled better when memory is tested after long- than when tested after short-delay intervals (LaBar and Cabeza, 2007, p. 55). Just like in the previous step, differences on memory retention between prospective and retrospective memories are apparent. Again, because of the importance of prospective memories, accurate retention is vital. Inaccurate and incomplete information retained has its consequences. And usually, when this happens the individual is taken at fault because he/she seems to have control over remembering prospective memory. On the other hand, for retrospective memories, when there are details that cannot be remembered, it is usually taken as a fact of life. People tend to forget about these things. When one remembers every detail for a retrospective memory, he or she is exceptional. 3. Memory retrieval The last step in creating memories is to make them retrievable. An easily retrievable memory is one that is (1) confidently dug up from all the information stored in the brain, and that is (2) containing most of the details. Like in the preceding two steps, amygdala is highly involved in this process (Phelps & Sharot, 2008, 150). Emotions give memories additional cues for retrieval (Kensinger, et al., 2004, p. 791). Although the mechanisms are not yet well identified, events that elicit strong activity from the amygdala are those that are recalled more vividly and confidently than neutral ones. These memories that are recalled vividly and persistently are called flashbulb memories (FBM). Initially, it was taught and is still believed by many that FBMs are all-encompassing detailed and accurate, like a flashbulb snapshot. However, what is recalled vividly and readily from each is the gist of the experience, and not the contextual details of the event. Either the details take longer to retrieve or are not recalled at all. For memories based on neutral experiences, on the other hand, they surface mainly through the context that surrounds the event. Because these are based on details, these memories from neutral experiences are harder to retrieve (Phelps & Sharot, 2008, 150-151). Retrieval of memories that are associated with strong emotions is especially important in survival. Confidence in a recalled incident permits quick action, which is important especially in dangerous situations. The problem with not recalling much of the details with a vividly recalled experience is that, there is a tendency for a person to add to the memory, details that may instigate the same emotional response, even if these details did not really happen (Phelps & Sharot, 2008, p. 151). For example, current beliefs can add onto the memory of past experiences (Aaker, Drolet & Griffin, 2008, p. 268). Considering this, emotions seem to make memory retrieval less accurate. Obviously, retrieval is more significant for prospective than for retrospective memories. Because there is much more importance in remembering prospective memories, people usually tend to will them to be brought to the surface even if still not needed. This is usually done just to make sure that the information are still intact, and nothing is missing. But by doing so, it makes the memory more prone to disruptive forces. REMEMBERING AND RECOGNIZING EMOTIONS 1. Recognizing emotions It is widely accepted that experiences to which one associates strong emotions to are more likely to be encoded and retained than neutral experiences do. When encoding emotions from new memories, the brain digs into old memories stored in the brain for certain information to associate with some certain items to be encoded. In addition, emotional experiences are more brought into surface than neutral experiences (Kensinger, et al., 2004, p. 791). However, the brain has found a way to control them, so that sudden resurfacing of emotional outbursts will be prevented. This, however, is a way for an individual to remember emotions during an event not by what it actually was, but by how it was modified using the past experiences and emotions that were also stored in the brain. Not only personal emotions are recognized and stored, but emotions of other people as well. As early as two months, humans incline to look at eyes over other facial features. This preference is carried over until adulthood. Because eyes give a lot of information about the general nature of complex emotions expressed by someone else, it is subconsciously used to discern whether the emotion is negative, positive or neutral. Thus, the amount of attention allotted to the eyes when judging which emotion is being expressed is critical in having an accurate perception of the new experience (Sullivan, Ruffman & Hutton, 2007, p. P53). 2. Mixed emotions One of the most interesting topics about emotion-memory interactions is the recollection of mixed emotions. The property of memory that greatly influences how one remembers emotions during a certain event is its flexibility. Over time, how one remembers emotions during an experience leans toward a unipolar emotion, and may be more positive or more negative than what was actually felt. For example, a set of mixed emotions turn more positive especially when negative emotions are just bursts interspersed in a generally positive feeling during the experience. Usually, what was felt immediately before the remembered event is the one retained as the overall emotion for that memory. These changes also occur as current beliefs, social norms and other memories are unconsciously taken into account when asked, “What did you feel during this time?” (Aaker, Drolet & Griffin, 2008, p. 269) FACTORS AFFECTING EMOTIONS AND MEMORY 1. Trauma For victims and soldiers of war who suffer from posttraumatic stress disorder (PTSD), combative pictures of guns and soldiers activates their amygdala much more than a neutral picture, such as the color wheel, when normally, all pictures should elicit the same response from the amygdala. PTSD patients are also easily more distracted by both combative and non-combative pictures in their working memory performance. They cannot discriminate against threat-related and non-threat related distracters to working memory performance (Morey et al., 2009, p. 815). Once this happens, the capacity to effectively maintain and select relevant information without getting distracted by irrelevant stimuli deteriorates. Low working memory performance relates to control of emotions, and causes a high occurrence of emotionally intrusive thoughts and unsuppressed emotions (Jha, et al., 2010, p. 55-56). This may be resulting to the hypervigilance observed among people with this disorder (Morey et al., 2009, p. 815). However, these clinical observations on PTSD patients are not a sole function of amygdao-hippocampal interaction. The ventrolateral prefrontal cortex (vlPFC) preserves working memory function by preventing distraction by disruptive information. For PTSD patients, together with amygdala’s, vlPFC’s activity is heightened when presented with negative stimuli. Still, with vlPFC, a different response is obtained from non-combative than combative pictures. Such is not the case with the dorsolateral prefrontal cortex (dlPFC). For PTSD patients, both combative and non-combative distracters are able to distract working memory function. As observed in previously-described instances, emotions get the upper hand on memory, and will be able to distract the working memory function, especially when the distraction is something that provokes a very strong emotion, such as combative pictures presented to war PTSD patients (Morey et al., 2009, p. 815). 2. Age and Alzheimer’s One of the most important functions of memories, is to provide the right information about the emotions being expressed by the face at that point. This is especially important among socialized beings who live within tolerance and respect. Rightfully judging emotions of others and acting accordingly are certainly important in our roles as social beings. However, age affects detection of emotions. When one becomes an old adult, the relative attention given to the eyes when trying to recognize emotions from facial expressions, gradually decreases. One plausible explanation is that, because the brain processing speed gradually declines with age, old adults have to spend more time looking at the eyes, to which older adults are not accustomed to (Sullivan, Ruffman &Hutton, 2007, p. P58) Aging seems to distort memories about emotions during experiences in a more positive direction. Apparently, older adults’ attention is more likely allocated to more positive or even neutral stimuli than to negative stimuli. When older and younger adults are compared, both initially react to negative pictures, but younger adults tend to dwell longer on these than older adults do. This means that emotion regulation function is better among older adults (Mather and Knight, 2006, P54-P56). Alzheimer’s disease is the current frontrunner of memory-deficit conditions, comprising of more than 50% of all dementia cases. Damage is mostly in the temporal lobe, entorhinal cortex, precuneus, posterior cingulated cortex, and hippocampus (Goodkind, et al., 2010, p. 31). It may be caused by disorganized brain neurons and extracellular amyloid plaques that accumulated over time. As such, adults are more likely to be affected by this condition. One of the critical effects of Alzheimer’s disease is that the enhancement of memory encoding and retention through emotions are gradually lost (Kensinger, et al., 2004, p. 792). In addition, control over emotional facial behaviour is impaired (Goodkind, et al., 2010, p. 36). However, Goodkind, et al. (2010, p. 35) has also reported that people who suffer from Alzheimer’s disease are able to regulate their emotions unless their memory and other cognitive resources are not burdened. CONCLUSION Because emotions and memories permit one to remember dangerous situations and to avoid them in the future, the interplay between emotions and memory is an innate animal function to protect survival. The main structures facilitating this connection are amygdala, for emotions, and hippocampus, for the memory. In the three steps of creating memories, (1) encoding, (2) retention, and (3) retrieval, emotions were seen to play in modulating and enhancing memories. This collaboration is mainly a function of the amygdalo-hippocamal junction that permits enhancing memories through emotions and remembering emotions by imploring past memories as well. The partnership of these two structures, and their association with other brain structures as well, must keep up with how dynamic emotions and memories needs to be. The differences on the demands and importance of retrospective and prospective memories make creating memories much more complex. Like any other physiological function, emotions and memories, and how they interact with each other are affected by aging and health conditions. As one ages, the tendency to recall positive experiences is much more than the tendency to recall negative or neutral ones because the cognitive control on emotions become strategically enhance with age. However, as one ages, an individual becomes more prone to neuropathological conditions causing Alzheimer’s disease, causing memory deterioration and even loss of emotion’s effect on memory. And because brain is an integrated unit, other brain structures are also involved in emotions and memories, too. Dorsolateral and ventrolateral prefrontal cortex, and sensory processors also has functions similar to or in concert with that of amygdala or hippocampus, and thus should also be performed a similarly in-depth analyses on. REFERENCES Aaker, J., Drolet, A., & Griffin, D. (2008). Recalling mixed emotions. Journal of Consumer Research, 35, 268-278. Abraham, W. (2006). Memory maintenance: The changing nature of neural mechanisms. Current Direction in Psychological Science, 15(1), 4-8. Glascher, J., Rose, M., & Buchel, C. (2007). Independent effects of emotion and working memory load on visual activation in the lateral occipital complex. The Journal of Neuroscience, 27(16), 4366-4373. Goodkind, M., Gyurak, A., McCarthy, M., & Miller, B. (2010). Emotion regulation deficits in frontotemporal lobar degeneration and Alzheimer's disease. Psychology and Aging, 25(1), 30-37. Jha, A., Stanley, E., Kiyonaga, A., Wong, L., & Gelfand, L. (2010). Examining the protective effects of mindfulness training on working memory capacity and affective experience. Emotion, 10(1), 54-64. Kensinger, E. A., Anderson, A., Growdon, J. H., & Corkin, S. (2004). Effects of Alzheimer’s disease on memory for verbal emotional information. Neuropsychologia, 42, 791-800. Kliegel, M., & Jager, T. (2006). The influence of negative emotions on prospective memory: A review and new data. International Journal of Computational Cognition, 4(1), 1-17. LaBar, K. S., & Cabeza, R. (2006). Cognitive neuroscience of emotional memory. Nature, 7, 54-64. Mather, M. & Knight, M. R. (2006). Angry faces get noticed quickly: threat detection is not impaired among older adults. Journal of Gerontology, 61B(1), P54-P57. Morey, R., Dolcos, F., Petty, C., Cooper, D., Hayes, J., LaBar, K., & McCarthy, G. (2008). The role of trauma-related distracters on neural systems for working memory and emotion processing in posttraumatic stress disorder. Journal of Psychiatric Research. 809-817. Phelps, E. (2004). Human emotion and memory: interactions of the amygdala and hippocampal complex. Current Opinion in Neurobiology, 14, 198-202. Phelps, E., & Sharot, T. (2008). How (and why) emotion enhances the subjective sense of recollection. Current Directions in Psychological Science, 17(2), 147-152. Sullivan, S., Ruffman, T. & Hutton, S. B. (2007). Age differences in emotion recognition skills and the visual scanning of emotion faces. Journal of Gerontology, 62B(1), P53-P60. Read More