Motivation and emotion/Book/2013/Memory and emotion

Emotion and memory:
How does emotion affect memory?

Multimedia presentation (5 min)

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An experience may be so exciting emotionally as almost to leave a scar on the cerebral tissues (James, 1980).

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Overview

Emotion can heavily affect ones Memory (Cabeza & LaBar, 2006). Emotions are defined as "short-lived, feeling-arousal-purposive-expressive phenomena that help us adapt to the opportunities and challenges we face during important life events" (Schneider, 2007). Memory is the capacity to store and retrieve information which are explained further below (Campbell, Cumming, Gerrig, Wilkes, & Zimbardo, 2008). Many things can contribute to the effects of emotion on memory, and multiple parts of the brain contribute to the connective function of emotion and memory. Emotional stimuli, mood, and contextual features all effect our memories such that they are often remembered better than neutral stimuli, particularly where perceptually salient details are concerned (Gross & Richards, 2006). Memory is not a perfect record of our experiences some people remembering an emotional experience completely and accurately, while others left with bits and pieces (Loftus, 1993). Davis and Follette (2001) found that emotion enhances attention which is a distinct cognitive construct necessary for forming new memories. A good example of emotion effecting memory and its reliability is research of eyewitness testimony. Elizabeth Loftus (1979) an influential researcher of eyewitness memory concluded that memories were quite vulnerable to distortion from post event information (Loftus & Wells, 2003). Another example is depression, stress, and anxiety, these can disrupt concentration which can affect memory (Gross & Richards, 2006). Theories discussed within this chapter will delve into the why and how of the effects of emotion on memory.

Memory is processed in three stages

Encoding	Encoding is the first step of information processing that leads to a representation in memory for later retrieval
Storage	Storage is the retention over time of information encoded
Retrieval	Retrieval is the recovery of encoded and stored information from long-term memory

Two types of memory

Short term memory	Short term memory is the memory process associated with preservation of recent experiences and with retrieval of information from long-term memory.
Long term memory	Long term memory is the memory process associated with preservation of (theoretically unlimited) information for retrieval at a later time.

The Amygdala and Hippocampus role in emotion and memory

The Amygdala and Hippocampus are both part of the Limbic system, the brain structure thats functions involve emotion, behaviour and long-term memory. The brain region most involved in emotional memory is the amygdala. The amygdala is involved in assessing the emotional significance of events. The amygdala is also seen to be particularly sensitive to negative experiences. The hippocampus is known for its role in the formation of new memories about experiences and events (using the storage function of memory). The Cerebellum is also involved in remembering strong emotions, specifically in strengthening long-term memories of fear. The hippocampus, Prefrontal cortex and the cerebellum, collaborate to determine how we store memory from the past and present, based on our emotions (LeDoux, 2000).

Quick facts on how emotions can effect memory

Emotionally charged events are remembered better than less emotionally charged events.
Pleasant emotions are typically remembered better than unpleasant emotions as positive memories have more contextual details which helps memory recall.
Strong emotion can impair memory for less emotional events and information encoded at the same time.
It is emotional arousal the helps memory not the importance of the information.
Retrieval of a memory is easier when your mood matches the mood you were in when you encoded the information
The stronger the emotional arousal, the greater its effect on memory.
Emotions can be dulled or evoked by displaying or suppressing expressions of emotion.

Trauma and memory

Psychological trauma can result from a traumatic event or experience and be the cause of long term emotional and memory problems. The area of memory most commonly effected by emotional trauma is long-term memory i.e. missing memories, intensified memories, and changes to memory. Trauma is caused from intense emotion, especially if a near death experience is had. The link between emotions and memory is an integral part in the effects of trauma on memory. Emotional events are recalled with more frequency and vividness than memories not associated with intense emotions. Traumatic events such as a car accident or sexual abuse, are associated with strong negative emotions and the memories of these events tend to be very strong and more easily recalled than memories of lessor degree, such as neutral or positive emotions. As mentioned earlier attention plays an important part in emotion's connection to memory. If one is heavily emotionally involved in an event much of their attention is focused on what is going on around them, thus creating a stronger memory (Van der Kolk, 1998).

Post traumatic stress disorder

Posttraumatic stress disorder (PTDS) is another example of emotions effecting memories. PTSD is an anxiety disorder caused from a fear inducing experience or event involving threat of physical harm. The stress of PTSD can effect the hippocampus creating problems with transferring information from short-term to long-term memory (Cabez & LaBar, 2006). There are many symptoms of PTSD though symptoms relevant to this section are emotional numbness and one of the most common and powerful symptoms - the random recurrence of intense memories that caused the PTSD; This can happen in different ways ie. flashbacks or unwanted thoughts related to the trauma. Neurobiological models of PTSD have found brain regions and stress hormones that are involved in fear, arousal and most importantly emotional memory. Chronic stress in PTSD has shown to display smaller volume in the hippocampus and declarative memory deficits (Cabez & LaBar, 2006).

Repressed memories

Repressed memories are another theory of what can happen to information stored in long-term memory as a result of trauma. It is the idea that a traumatic event of high levels of emotion and stress are able to be repressed from consciousness so the memory is blocked from being retrieved. Some psychologists claim repressed memories can be recovered through therapy, though, this can be tricky as to not manipulate memories or create false memories. This is a controversial topic therefore will not be extensively discussed (Clancy, McNally, & Schacter, 2001; Hansen & Hansen, 1998).

Dissociative amnesia

Dissociative amnesia is when the normally well-integrated functions of memory, identity, perception, or consciousness are dissociated (separated). It is primarily associated with trauma or severe stress, with a strong internal conflict that forces one to separate unacceptable knowledge, information, or feelings. Individuals with dissociative amnesia have extensive memory loss often forgetting important personal information or events. Dissociative amnesia memory loss is almost always anterograde meaning only the period directly following the event(s) is affected (DSM–IV–TR, 2000). This is another of the many examples of how psychological trauma can affect memory.

Tunnel memory - A study of different emotions effect on memory

Encoding and storage of memories focuses on different aspects of a situation depending on emotions experienced; Negative emotions are seen to focus on specific detail, whereas positive emotions tend to see the situation more broadly (Bluck & Levine, 2004). To test this hypothesis, Levine and Bluck (2004) looked into the effects of emotions on memory using the televised announcement of the O.J. Simpson murder trial verdict. Participants showed strong positive or negative emotions toward the trial depending on if they saw Simpson as guilty or not. Seven days after the verdict was seen by the participants, participants were asked how they felt about the trial verdict. 50% of participants reported being angry or sad about the verdict, 25% were happy, and 25% reported not caring. 14 months after the verdict, participants' were tested on their memory of the announcement by asking which items on a list of events occurred during the announcement. Half of the items on the list happened, and the other half were made up. As predicted, participants who felt happy about the verdict tended to recall the verdicts details better than the sad, angry, or neutral participants. However, the happy participants also reported more false positives listing items that did not occur. Negative emotion participants recalled less about the event overall, though made fewer errors of commission (responding when you are not supposed to). Therefore, the research found the happier or angrier the person felt about the event, the more vivid their memory (Dingfelder, 2005).

Retrieval of emotional memories

Memory retrieval refers to “the access, selection, reactivation, or reconstruction of stored internal representations” (Buchanan, 2007).

Fun fact! Ever wondered how a smell can instantaneously trigger an emotion or vivid memory? Out of the five senses, smell is the strongest and most direct connection to memory. This is because of an important part of the limbic system called the olfactory bulb. The olfactory bulb works closely with the amygdala (which if you can remember processes emotion), and the hippocampus which is responsible for associative learning. When you first encounter a smell, the hippocampus links this smell to a memory of an event; then the next time you encounter this smell the association is remembered and the amygdala links this to the emotion felt at this time (Baddeley, 1999; Buchanan, 2007). Can you think of the last time this happened to you? (For more info see Smell and emotion )

Contextual effects

Contextual effects are just one way emotion can influence retrieval of memories. Contextual effects refer to your emotional state at the time of encoding or retrieving. Two types of effects exist, the mood congruence effect and mood state dependent retrieval, both similar in the function though using different cues for retrieval. They can both assist in the retrieval of memories (Blaney, 1986).

The mood congruence effect:

The mood congruence effect is the phenomena by which we remember events that match our current mood. An example of this would be if you are in a happy mood you are more likely to remember positive events. Another situation this is evident is research of individuals with depression; Depressed people are more likely to remember events that are negative rather than positive.

Mood-state dependent retrieval:

Mood-state dependent retrieval is the idea that remembering is easier when your mood at retrieval matches your mood at when you encoded the information. Therefore, if you induce the same emotional state that was experienced at the time of the event you have a better chance of accurately remembering the information.

Emotion regulation

Everyday whether you know it or not you are actively regulating your emotions in a variety of ways. Gross's (1998) process model of emotion regulation suggests strategies that are undertaken early in the emotion-generative process have different consequences than strategies that are undertaken later in the process. A commonly used strategy called down-regulating emotion is where reappraisal comes early in the emotion-generative process; It also involves changing the direction of the emotional response by changing your perception of the emotional stimuli thus reducing the emotional response. Another strategy is suppression, which comes later in the emotion-generative process consisting of inhibiting the outward expression of internal feelings and the ongoing emotion-expressive behaviour. It is suggested self-regulatory demands from emotion regulation may come at a cognitive price; greater use of suppression causes worse memory (Gross, 1998).

Easterbrook (1959) previously stated that "emotion hurts memory"; Easterbrook’s cue-utilization hypothesis argues that emotions can have an "attentional narrowing effect" that diminishes memory straight after an event has occurred. However, Richards and Gross’s (2006) analyses gives an alternative explanation; More effort is put into hiding feelings as the intensity of an emotional feeling increases, thus we could expect that particularly emotional events also evoke particularly high levels of cognitively costly emotion regulatory effort. When looking at “emotion hurts memory” studies, they tend to show participants violent or gruesome stimuli, which may be more aversive and distasteful than stimuli typically used in “emotion helps memory” studies (i.e. hospital or accident scenes)(Richards & Gross, 2006).

Did you know: Not enough snooze, and you'll lose! - Sleep deprivation including quantity and quality of sleep is important to memory. Not getting enough sleep or constantly waking up throughout the night we know can make you grumpy and leaves you fatigued, but did you know it interferes with your ability to consolidate and retrieve information from memory (Gross, 2002).

Self help - Application to your life!

There are many suggestions on how to improve ones memory or help retrieve information more readily from memory, yet a little less common is the incorporation of emotion in the equation. As we have seen, different cues, emotions and contexts can effect the way or how much we store into memory and how well we can later retrieve memories. For this self help section the focus will be on mindfulness and how it can help mediate the connection between emotion and memory and improve how your emotions may effect your memory.

Mindfulness has been found to be a useful tool in psychology. Mindfulness is based on the interdependence of action, cognition, memory, and emotion (Epstein, 1999). Meditation can help improve depression, anxiety, chronic pain, diabetes, and even high blood pressure; it can also improve focus, concentration, creativity, and learning ability (Epstein, 1999). One perspective in relation to the topic is that mindfulness training can alter the processing of emotional information (Roberts-Wolfe et al., 2012). Studies of people that regularly meditate show more activity in their left prefrontal cortex, which is associated with feelings of joy and self-control. Meditation has also shown to increase the thickness of ones cerebral cortex and encourages more connections within the brain which all lead to greater mental sharpness and memory ability (Epstein, 1999). Mindfulness training can alter the processing of emotional information (Roberts-Wolfe et al., 2012). Roberts-Wolfe et al. (2012) investigated this by looking at the effects of mindfulness training on emotional information processing (i.e., memory). Mindfulness training was found to be associated with improvement of processing efficiency for positive stimuli. The improvements in emotional information processing were associated with improvements in psychological well being and lower depression and anxiety, suggesting mindfulness training may improve well being via changes in emotional information processing (Roberts-Wolfe et al., 2012).

Roberts-Wolfe et al. (2012) used self-report measures of anxiety and depression and measured wellbeing, before and after 12 weeks of either mindfulness meditation or a control condition. They found that mindfulness training was associated with increased positive word recall and well being than the control group. These increases were also associated with improvements in anxiety, depression and overall well being. An interesting note from this study was that change in emotional processing was specific to positive information.

How does mindfulness work you ask? In short, the meditator begins by focusing on a body-based meditation object such as sensations of breathing, and re-engages body awareness as a method of disengaging from distracting thoughts. Try it yourself! Here is an example of how to use mindfulness in your day-to-day life: You could be walking to work, to your car or around the block, start by taking a deep breath in and scan your surroundings. Notice the air temperature, light and shadows, different smells and sounds. As you walk, notice how your foot hits the pavement or grass and how it lifts up. Notice the points of contact. Notice how your body feels every part of it as it moves. Notice how your arms swing by your side and how you hold your hands and head. Be aware of each and every sensation. (For more info see Mindfulness )

Try it! It doesn't take long, so give it a go sometime! Here is a short video from 'Ted talks' on mindfulness and how to use mindfulness in your life mindfulness video

Quiz - Test your knowledge of the effects of emotion on memory!

Conclusion

The purpose of this chapter was to provide a comprehensive understanding of how emotion can affect memory. Previously there has been many suggestions on how to improve memory in general, less information is available about incorporating emotion into the equation; Throughout this chapter we have done just that. We have seen how memory works at a neurological level, the three processes of memory, and how the amygdala and hippocampus contribute. The effects of psychological trauma on memory was summarised focusing on PTSD, repressed memories, and dissociative amnesia, giving a good overview of the result of a psychologically traumatic event or experience and its cause of long term memory problems. A good example of different emotions effecting memory was given with the study of O.J. Simpson murder trial giving an interesting perspective on how perceiving something effects how we remember it. The ways in which memory can be more readily recalled looked at context effects and emotional regulation and how emotions can even trigger memories spontaneously. Evidently emotions can have strong effect on memory in a variety of ways and retrieval can be effected by a number of things. Lastly, Mindfulness was the chosen method to help you improve your emotional memory, which I hope by now you have considered trying yourself.

References

American Psychiatric Association. (2000). Diagnostic and Statistical Manual of Mental Disorders. 4th edition, text revised. Washington, DC: American Psychiatric Association.

Baddeley, A. D. (1997). Human memory: Theory and practice. Hove: Psychology Press.

Baddeley, A. D. (1999). Essentials of human memory. Hove: Psychology Press.

Blaney, P. H. (1986). Affect and memory: A review. Psychological bulletin, 99(2), 229.

Buchanan, T. W. (2007). Retrieval of emotional memories. Psychological bulletin, 133(5), 761.

Dolcos, F., LaBar, K. S. & Cabeza, R. (2005). Remembering one year later: Role of the amygdala and the medial temporal lobe memory system in retrieving emotional memories. Proceedings of the National Academy of Sciences, 102, 2626–2631.

Dingfelder, S. F. (2005). Feelings' sway over memory. APA Monitor on Psychology, 36(8), 54-55.

Epstein, R. M. (1999). Mindful practice. The Journal of the American Medical Association, 282(9), 833-839.

Gerrig, R. J., Zimbardo, P. G., Campbell, A. J., Cumming, S. R., & Wilkes, F. J. (2008). Psychology and life (Australian ed.). Sydney: Pearson Education Australia.

Gross, J. J. (2002). Emotion regulation: Affective, cognitive, and social consequences. Psychophysiology, 39(3), 281-291.

Hansen, R. D., & Hansen, C. H. (1988). Repression of emotionally tagged memories: The architecture of less complex emotions. Journal of Personality and Social Psychology, 55(5), 811.

James, W. (1890). The principles of psychology. New York: Holt.

LaBar, K. S., & Cabeza, R. (2006). Cognitive neuroscience of emotional memory. Nature Reviews Neuroscience, 7(1), 54-64.

LeDoux, J. E. (2000). Emotion circuits in the brain. Annual review of neuroscience, 23(1), 155-184.

Levine, L. J., & Bluck, S. (2004). Painting with broad strokes: Happiness and the malleability of event memory. Cognition and Emotion, 18, 559-574.

Loftus, E. F. (1979). Eyewitness testimony. Cambridge, MA: Harvard University Press.

McNally, R. J., Clancy, S. A., & Schacter, D. L. (2001). Directed forgetting of trauma cues in adults reporting repressed or recovered memories of childhood sexual abuse. Journal of abnormal psychology, 110(1), 151.

Richards, J. M., & Gross, J. J. (2006). Personality and emotional memory: How regulating emotion impairs memory for emotional events. Journal of Research in Personality, 40(5), 631-651.

Roberts-Wolfe, D., Sacchet, M., Hastings, E., Roth, H., & Britton, W. (2012). Mindfulness training alters emotional memory recall compared to active controls: Support for an emotional information processing model of mindfulness. Frontiers in human neuroscience, 5, 15.

Schneider, T. (2007). The Clinician, the Brain, and 'I'. United Kingdom: Taylor & Francis.

Van der Kolk, B. A. (1998). Trauma and memory. Psychiatry and Clinical Neurosciences, 52, S52-S64.

Wells, G. L. & Loftus, E. F. (2003). Eyewitness memory for people and events. In A.M. Goldstein (Ed.), Handbook of psychology: Forensic psychology (Vol. 11, pp.149-160). New York: Wiley.

	The brain region most involved in emotional memory.
	Is a part of a limbic system.
	Is particularly sensitive to negative experiences.
	All of the above.

	There is no difference in remembering.
	Unpleasant; Pleasant.
	Sad; Happy.
	Pleasant; Unpleasant.

	We remember events that match our current mood.
	Remembering is easier when your mood at retrieval matches your mood at when you encoded the information.
	Depressed individuals remember more negative events.
	It is the same as the mood congruence effect.

	TRUE.
	FALSE.

	TRUE.
	FALSE.