Impairment of Memory due to Stress
Regardless of age, gender, race or other factors, experiencing stress every day is one of the many things we all have in common. Various studies have concluded how stress negatively affects both physical and mental aspects of our being. This paper intends to present how stress significantly contributes to the impairment of one’s memory. To address this, this paper also provides practical interventions, with primary focus on meditation, how to control stress and, thus, enhance memory.
To understand the relationship between stress and memory better, it would be helpful to start the discussion briefly describing these terms independently. Discussion on how stress affects memory and the interventions then follow.
Stress is generally defined as an organism’s total response to environmental demands or pressures. It can come from any event or thought that may cause frustration, anger, or nervousness (“Stress and anxiety – overview,” 2011). Stressful experiences may include major life events, traumas, and abuses that may originate from home, workplace, or neighbourhood. (McEwen, 1998).
To be more precise, we differentiate the types of stress which include: (American Psychological Association, n.d.)
- Acute stress. It is the most common form of stress, usually a short-term one, which is caused by demands and pressures of the recent past and anticipated demands of the future. Examples of this type of stress may include deadline that one is rushing to meet, car accident damaging the headlights, or loss of coveted contract, among others.
- Episodic stress. This type of stress occurs when acute stress is experienced frequently and is often suffered by people who are crisis-prone and leading chaotic lives.
- Chronic stress. It is the grinding type of stress that wears people away day after day. People under chronic stress never see a solution from miserable situations, such as poverty, dysfunctional family, or unhappy marriage.
For this paper, the focus is on acute stress. That is why the purposes of discussion acute stress would be referred to as stress.
According to the Miller-Keane Encyclopedia (2003), memory is the mental ability that enables person to keep and remember feelings, impressions, data, and ideas experienced before. For the process of learning to be completed, the ability of the brain to remember and use learning gained from past experiences is critical. The part of the brain which facilitates memory is called the hippocampus (“Stress and memory”, 2004).
Memory follows a three-step process which begins with encoding or placing the things, which we experience, into the memory. This is followed by consolidation or retaining information and then by retrieval wherein the information that has been stored in the memory is reactivated (Stangor, 2010). Sometimes, a fourth step called reconsolidation happens when memory enters an unstable state that it has to be stabilized anew (Schwabe, Joels, Roozendaal, Wolf & Oitzl, 2012).
How Stress Affects Memory
When stress is experienced, a class of steroid hormones called glucocorticoids, or more commonly referred to as corticosteroids or cortisol, is secreted from the adrenal glands (“Stress and memory”, 2004). Currently there are two schools of thought on the effect of stress to memory. One is that high levels of stress hormones during short-term stress may actually enhance memory consolidation and working memory with greater concentration on immediate events (“Stress and anxiety”, 2011). On the contrary, sustained stress is said to damage the hippocampus, thus impairing memory, particularly, a verbal one (“Stress and memory”, 2004). The difference in effect may be due to how cortisol affects glucocorticoid receptors in the hippocampus and prefrontal cortex (“Stress and anxiety”, 2011).
Another finding based on the study conducted by Schwabe et al (2012) is that the effect of stress on all memory processes is actually time dependent. This means that memory is either enhanced or impaired by stress depending on the timing the stress was introduced.
As mentioned earlier, memory processes, particularly memory consolidation and retrieval, are affected by the concerted action of stress hormones, namely glucocorticoids and noradrenaline, in the basolateral amygdale. According to Schwabe et al (2012), stress improves memory if it is experienced within the context of the learning episode. Furthermore, a positive effect is seen if the hormones and neurotransmitters, which are released in response to stress, act on those brain circuits that are activated by the learning episode.
On the other hand, findings based on the same study say that stress impairs memory if it is experienced out of the learning context, i.e. without any link to the learning experience or if the stress is experienced long before or after learning (Schwabe et al, 2012). This is because the glucocorticoid action is already in the genomic mode, meaning delayed and long lasting, and already active, for information processes are suppressed. In addition, the said condition impairs learning of information unrelated to the release of stress hormones. So if there is no direct relation between the stressor and memory test, then memory is impaired by stress.
Given the adverse effects of sustained stress to memory, which is critical to learning, everyone should be aware of how to manage stress in various ways. Learning stress management would not only help enhance one’s memory but the whole well-being as well.
Interventions – Stress Management
There are various ways to handle stress, which include:
- Exercise. It is in any form can effectively serve to relieve stress as one focuses on a task that helps make one calm (Price, 1998). Ongoing exercise interventions have likewise been found to improve memory processes, particularly in older adults and children. This may be attributed to the positive regulation of hippocampal neurogenesis, wherein newborn neurons that act as the foundation for the formation of new memories have higher chances of surviving (van Praag, Kempermann & Gage, 1999).
- Music. Different aspects may also be improved through learning music. A study conducted by Bugos, Perlstein, McCrae, Brophy and Bedenbaugh (2007) showed that adults, who participated in an individualized piano instruction, with no previous musical training exhibited substantially better performance on tasks designed to test attention and working memory relatively to a healthy control group.
- Meditation. Studies have indicated that meditation reduces stress related cortisol secretion, thus leading to improved memory and lower stress levels (Levy, Wobbrock, Kaszniak & Ostergen, 2012).
Meditation has been practiced for ages in various cultures (Price, 1998). Known practitioners of meditation are the Buddhists. In a study conducted by Luders, Toga, Lepore & Gaser (2009), magnetic resonance imaging of Buddhist insight meditation practitioners revealed that this group have physical changes in their brain structure such as the increased cortical thickness and hippocampus volume as compared to the control group.
Meditation comes in various forms: (Monaghan & Viereck, 2011)
- Guided meditation – also known as visualization. This type of meditation involves the formation in one’s mind the images of places or situations that one may find relaxing through the use of as many senses as possible. A guide or teacher may facilitate meditation.
- Mantra meditation entails repeating an easeful word, idea, or phrase to avert distracting thoughts.
- Mindfulness meditation. In this type of meditation, practitioners increase awareness and acceptance of living in the present moment. One observes thoughts and feelings sans judgment.
- Qi gong and Tai-chi. These are parts of the traditional Chinese medicine that combines meditation with physical movement to restore balance.
- Transcendental meditation – With this type of meditation, the practitioner uses a mantra, which maybe a phrase, sound, or word, silently repeated to facilitate narrowing of conscious awareness and elimination of all thoughts in the mind.
Given the multiple benefits of meditation, an increasing number of schools have adopted meditation programs for their students. Researchers have found many positive outcomes for students who meditate. For instance, a study by Semple, Reid and Miller (Vega, 2012) showed decreased anxiety among the students of 7-8 grades. Another study having similar findings among students of 1-3 grades has also been done by Krech Napoli and Holley (Vega, 2012).
To further support the hypothesis that stress indeed negatively impacts memory and meditation helps in countering this effect, a survey through brief interview was conducted among 30 respondents. The respondents were composed of two groups; the first includes fifteen students who have just attended a meditation class with two 30-minute sessions per week, while the second includes students who have other ways of dealing with stress. At the onset of the survey, the respondents will be asked if they experience stress from academic matters, how stress affect their daily lives and what do they do to beat stress. For the follow-up interview, which happens after three weeks, the same respondents will be asked if they experience any change, especially with their memory, relative to how they manage stress.
For both groups, respondents all agreed that their studies are the major source of stress at the moment. Almost everyone also mentioned that such stress somehow affects their memory so they rely heavily on making lists or setting alarms to remind them of deadlines, exams and other activities. In addition, 25 out of the 30 respondents also believe that the lack of sleep on school days increases stress and adversely affects memory. In terms of stress management, the first group reckons that meditation would effectively assist in lowering stress levels. The second group, on the other hand, is inclined to hang out with peers, watch movies, dine out or go shopping to manage stress.
After three weeks, the survey of the first group reveals that twelve out of the fifteen respondents experienced notable change in their overall well-being, including their memory, after practicing meditation. The remaining three respondents said they experienced only a slight change but more sessions are highly likely to cause greater improvements. Meanwhile, five out of the fifteen students in the second group asserted that their alternative methods are effective in improving their memory. Ten respondents from the second group agreed that their methods did not affect their memory but did relieve them of stress for the short-term.
Stress, although it may have a positive side, is shown to have adverse effects on the memory faculty and, thus, on learning. Whatever we do, we could not completely eliminate stress from our lives, as it is critical in honing survival skills. However, what we can do is to be aware of our stressors and know how to control them. In this regard, learning how to manage stress should be one tool that everybody has to be equipped with.
As engagement in exercise through sports and learning music are already prevalent practices in all schools. Making meditation a mandatory part of curriculum in all educational institutions nationwide should be seriously considered by legislators. Children in school age, especially adolescents who are usually confronted by stress coming from peer pressure, school matters, future decisions, and family issues (Phill, n.d.), must be empowered through meditation. Many studies have already proven the multiple benefits derived from practicing meditation by young people. These claims are also further supported by the survey conducted, wherein majority of the respondents practicing meditation acknowledged the positive effects of this method on their well-being.
Another proposal to be taken into account is for local community councils to have meditation programs for people within the community. It would facilitate not only the improvement of individual’s well-being but the entire community’s as well.