Treffer: Classroom Stress Promotes Motivated Forgetting of Mathematics Knowledge
Postsecondary Education
Weitere Informationen
The ability to retain educationally relevant content in a readily accessible state in memory is critical for students at all stages in schooling. We hypothesized that a high degree of stress in mathematics courses can threaten students' mathematics self-concept and lead to a motivation to forget course content. We tested the aforementioned hypothesis by recruiting students from a college course on multivariate calculus. Students were asked to report their ongoing stress in the course. The forgetting rate was assessed by comparing students' final exam performance against their performance for a subset of the same final exam items 2 weeks later. We found that among students with a strong mathematics self-concept, a higher amount of ongoing weekly stress during the course was associated with increased forgetting of course content and a higher report of avoidant thinking about the course. Neither of these associations was found among students with a weaker mathematics self-concept. Our results provide evidence for a scientific account of the affective and motivational forces that shape why students forget educationally relevant content. We discuss the various educational practices that cue forgetting and make recommendations for reducing motivated forgetting in the classroom.
As Provided
Classroom Stress Promotes Motivated Forgetting of Mathematics Knowledge
<cn> <bold>By: Gerardo Ramirez</bold>>
> <bold>Ian M. McDonough</bold>
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> <bold>Ling Jin</bold>
>
<bold>Acknowledgement: </bold>We would like to thank David Taylor for his help with recruitment. This research was supported by Faculty Career Development Award to the PI from the University of California, Los Angeles.
A popular belief among students is that much of what is learned during class is forgotten soon after they are done with classes. Researchers commonly attribute forgetting to the disuse of the target information, interference from competing information, or the absence of the target information’s retrieval cues. More recently, it has been argued that forgetting can also occur because of a deliberate process or motivation to exclude unwanted memories from our awareness (Anderson & Green, 2001). The motivated forgetting perspective broadly posits that internal drives can lead individuals to forget unpleasant memories that threaten the self. In the current study, we argue that one context in which people should be the most motivated to
Motivated Forgetting
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Motivated forgetting is the process by which people have difficulty recalling information and memories for events that are unpleasant, painful, or generally threating to the self-perceptions that individuals strive to maintain (Ceci & Bruck, 1995; Thompson, Morton, & Fraser, 1997; Tajfel & Turner, 1986). By preventing the successful retrieval of these types of memories, motivated forgetting processes are believed to serve an adaptive function that helps preserve psychological well-being (DePrince et al., 2012). Research across clinical, social, and cognitive psychology provides strong evidence supporting this assertion. For instance, clinical and research accounts have reported that forgetting of traumatic information can be caused by memories of death, murder, and war (Arrigo & Pezdek, 1997; Belli, 2012; Pyszora, Barker, & Kopelman, 2003; Rivers, 1917), as well as childhood abuse at the hands of a trusted caregiver (Bowman, 1996; Herman & Schatzow, 1987).
Evidence of motivated forgetting has also been observed in more commonplace circumstances. Several studies investigating memory for historical passages show that people are less able to recall statements about historical atrocities when the perpetrators of those atrocities belong to the individual’s cultural in-group (Imhoff & Banse, 2009; Rotella & Richeson, 2013). For instance, Sahdra and Ross (2007) found that Hindus who strongly identify with their in-group were the worst at recalling instances where Hindus engaged in aggression toward Sikhs (and vice versa). This research suggests that one way individuals are able to maintain a self-serving history is by participating in a motivated forgetting process that reduces accessibility of historical information.
Individuals experience a similar motivated forgetting process when they receive individual level diagnostic history. Researchers investigating mnemic neglect ask participants to fill out personality surveys, which are then used to provide individuals with diagnostic feedback about their personality and behavior. This feedback varies as to whether it describes behaviors that are central or peripheral to the self, as well as whether the feedback is positive or negative. Oftentimes, when individuals are asked to recall previously given feedback, they are equally good at recalling both negative and positive feedback concerning behaviors peripheral to the self. However, when individuals are asked to recall feedback concerning behaviors central to the self, they are generally worse at recalling negative than positive feedback (Sedikides & Green, 2004). Work on mnemic neglect suggests that it is not simply that people are bad at recalling negative or unpleasant information, but rather that people show deficient recall (i.e., forgetting) of feedback that is threatening to a central part of the self.
More recent support for motivated forgetting has been informative in addressing a common criticism that can be raised about much of the aforementioned literature. For instance, one criticism of the motivated forgetting literature is that the threatening information that individuals experience might lead to deficient encoding of information rather than reductions in the retrievability of information after encoding (i.e., storage and retrieval). As an example of this deficient-encoding hypothesis, women show impaired note-taking activities following a manipulation that threatens their identity in science and mathematics (Appel, Kronberger, & Aronson, 2011). There are at least two studies that provide evidence that motivated forgetting can occur even when information was successfully encoded. These studies ask participants to encode neutral information prior to receiving information that is threatening to the self.
Shu, Gino, and Bazerman (2011) studied the ways in which people justify dishonest behaviors by forgetting moral rules. Shu et al. reasoned that when individuals commit dishonest behaviors that threaten their self-image as good and moral people (Aquino & Reed, 2002), it is advantageous that they strategically forget moral rules. To test this, researchers asked participants to memorize an ostensibly neutral “honor code,” solve a problem-solving task, and then pay themselves for every problem they solved correctly. The authors found that participants who cheated by understating how much they actually paid themselves went on to remember less of the honor code during a memory test at the end of the experiment, compared with participants who did not cheat.
Another study asked whether people show reduced recall for neutral information linked to an identity threatened after the encoding phase. Dalton and Huang (2014) asked college students to memorize a set of neutral commercial advertisements that were either linked to their university (i.e., HKU students get 10% off) or not linked to their university (i.e., get 10% off). Following this neutral encoding task, participants either received threatening information (i.e., your institution is performing below other local universities) or nonthreatening information (i.e., your institution is on par with other local universities). Participants demonstrated poorer memory performance for the advertisements when they received the threatening relative to the nonthreatening information, but only if the advertisements were linked to their university. Dalton and Huang (2014) argued that threats to participants’ university identity led to a motivation to forget even neutral information when linked to their threatened self-concept. Thus, in both studies participants encoded the information equally well, but motivational processes led to more forgetting of that information when individuals perceived it as a threat to the self.
Common Tenets in Motivated Forgetting
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As reviewed previously, a diverse body of work provides ample evidence for motivated forgetting. Based on this evidence, we have identified two key tenets that inform our current research design and hypothesis. First, work on motivated forgetting suggests that people have some control over the process of forgetting. Basic memory research provides strong evidence that motives and directives can lead to real difficulty bringing memories to mind. For instance, Bjork and Bjork (1996) and others (e.g., Davis & Okada, 1971; MacLeod, 1998) maintain that explicitly directing individuals to forget words previously committed to memory can subsequently lead to an inability to recall this information (for review, see Bjork, Bjork, & Anderson, 1998). Participants in directed forgetting studies are not simply demonstrating demand effects; people continue to show poor recall even when they are provided a monetary incentive for successfully recalling the words they were previously asked to forget (MacLeod, 1999; Woodward & Bjork, 1971). Similarly, Anderson and Green (2001) demonstrate that the more times participants are instructed to inhibit particular words (using a think/no-think paradigm), the less likely they are to retrieve those words at a later recall test. Converging neuroimaging evidence also notes that this ability to control forgetting is associated with reduced activation in brain regions thought to be involved in memory retention (i.e., hippocampus), as well as increased activation in attentional control regions of the brain (i.e., the dorsolateral prefrontal cortex; Anderson et al., 2004; Benoit, Hulbert, Huddleston, & Anderson, 2015). There is clear support for the premise that individuals are capable of goal-directed forgetting via
A second common tenet in the literature argues that the motivation to forget stems from the desire to protect one’s self-concept. Self-concept refers to a predominantly positive mental representation of how people perceives themselves (Baumeister, 1998; Conway & Pleydell-Pearce, 2000; Gaertner, Sedikides, Vevea, & Iuzzini, 2002). The claim that threats to the self activate a type of psychological immune system with an impetus to protect one’s self-concept goes back as far as Freud (1937), but is also a basic tenet in self-affirmation theory (Sherman & Cohen, 2006). Self-affirmation theory focuses on how individuals adapt and respond to experiences that threaten the self-concept. When situations create a threat to the self, individuals respond in a defensive manner and enlist a number of strategies that dismiss, deny, or avoid the threat in an effort to reaffirm the self. Some of these strategies involve making downward social comparisons against other individuals who are clearly inferior (Fein, Hoshino-Browne, Davies, & Spencer, 2003), misidentifying or downplaying the importance of the domain they are performing in (Major, Spencer, Schmader, Wolfe, & Crocker, 1998), or distancing themselves from situations and people that confirm a threat (Goff, Steele, & Davies, 2008). We and others (Dalton & Huang, 2014; Green, Sedikides, & Gregg, 2008) borrow from self-affirmation theory to argue that memories that threaten a concept central to the self are likely to cue a pronounced motivation to forget.
We draw on the aforementioned tenets of the motivated forgetting literature to ask whether college students, who often are forced to contend with unpleasant course experiences, are at risk of forgetting important content once the class is over. We also address how students’ own self-perceptions for the domain under study (in this case mathematics) moderate the effects of the unpleasant course experience to produce a motivation to forget.
Motivated Forgetting Within Education
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One context where students are highly motivated to retain course content, but often report quickly forgetting, is the classroom (Bahrick, 1979). Curiously, there has been no work on motivated forgetting that focuses on real-world course content or fieldwork within the context of education. College classrooms, in particular, are an ideal place for studying motivated forgetting; students enter college with a strong academic self-concept yet are constantly challenged by a host of experiences in the classroom (Major et al., 1998; Marsh, 1991).
If motivated forgetting does occur within college courses, we reasoned that threats to students’ academic self-concept most likely occur within challenging mathematics courses. Mathematics courses are often rated as the most difficult (Hoyt & Lee, 2002), receive the lowest course ratings (Centra, 2009), and commonly create aversive learning experiences for students across all stages in schooling (Hembree, 1990; Jackson & Leffingwell, 1999). In fact, many individuals suffer from a form of anxiety that is specific to mathematics (what is termed math anxiety). Math anxiety can emerge early in schooling (Ramirez, Chang, Maloney, Levine, & Beilock, 2016), stems from the negative attitudes and beliefs of parents as well as teachers (Beilock, Gunderson, Ramirez, & Levine, 2010; Maloney, Ramirez, Gunderson, Levine, & Beilock, 2015), and has even been associated with activation in brain regions associated with the visceral sensation of pain, threat, and vigilance (Lyons & Beilock, 2012; Pizzie & Krammer, 2016).
Stress and anxiety in regards to mathematics is a common problem even among college students who are quite competent and have strong perceptions about their mathematics ability. For instance, college students who can easily perform basic arithmetic operations and count dots are impaired under the duress of mathematics anxiety (Ashcraft & Kirk, 2001; Maloney, Ansari, & Fugelsang, 2011; Maloney, Risko, Ansari, & Fugelsang, 2010). In fact, international comparison studies reveal that students from countries with the highest levels of achievement (e.g., Singapore and Czech Republic) are most at risk for demonstrating declines in achievement because of mathematics anxiety (Organization for Economic Cooperation and Development, 2013). Mathematics is also a domain where negative ability stereotypes continue to exist even for highly competent college students. Women and underrepresented students in college must contend with negative ability stereotypes about their potential ability in mathematics, which can create additional stress and fear about confirming these existing negative stereotypes (Steele & Aronson, 1995). It is clear that stress and anxiety around mathematics are capable of derailing the educational outcomes of all students, even those who show high ability and great promise in mathematics.
If classroom experiences create threatening memories for students, this would suggest that the very same context where students are most motivated to remember course content might ironically create a powerful motivation for students to forget that course content instead. In fact, one study found that high-achieving women demonstrate more forgetting of algebra knowledge over time (Bahrick & Hall, 1991), which provides indirect evidence that populations who experience added stress in regards to mathematics are at risk for forgetting.
It is certainly the case that not all students who experience ongoing stress around their mathematics course may feel threatened by these experiences and therefore motivated to forget. Rather, students with high self-perceptions of mathematics ability (i.e., mathematics self-concept; Wigfield & Karpathian, 1991) should be the most vulnerable to forget. For students with a high mathematics self-concept, a high degree of ongoing course stress may undermine students’ beliefs that their self-concept is adequately defined, stable, or internally consistent (Campbell et al., 1996). For example, experiencing social, financial, and work stress has been associated with a reduction in the extent to which individuals believe they have a clear idea of who they are (De Cremer & Sedikides, 2005; Lavallee & Campbell, 1995; Nezlek & Plesko, 2001; Ritchie, Sedikides, Wildschut, Arndt, & Gidron, 2011). Stressful classroom events may be threatening, in part, because they challenge one’s daily assumptions and perceptions about their ability in mathematics. One way in which students might respond to such threats to the self is by creating a defensive response that seeks to minimize the accessibility of memories (i.e., motivated forgetting). Hence, students high in mathematics self-concept and whose course experience is characterized by a high degree of stress may come to interpret their stressful experiences as a threat to the assumptions they have about their abilities (e.g., “Mathematics is supposed to be something I am good at, so why am I feeling so stressed out by this class?”). If this is the case, then students with the highest self-concept for mathematics may be at risk for motivated forgetting. Thus, we ask:
We focus on studying motivated forgetting at the conclusion of the course, when students may be most likely to deem the course content no longer relevant for retention (Bunce, VandenPlas, & Soulis, 2011; Khanna, Brack, & Finken, 2013). Hence, for the purposes of this study, we operationalized forgetting as the difference between students’ performance on their final exam and their performance on a subset of the same final exam items given two weeks after the completion of the course. In this way, we tested whether stressful classroom experiences lead to motivated forgetting of classroom content after the course is over.
To the extent that we could find evidence for our first research question, we also must rule out several alternative interpretations. One possibility is that students with higher ongoing stress and higher mathematics self-concept may perform very well on the original exam which, ironically, leaves them with more to lose on the follow-up exam two weeks later. A significant interaction between stress and mathematics self-concept on
While higher ongoing stress could lead students to differentially encode the course material, our intuition was that all students in the course would be equally motivated to effectively encode the material and perform well in this very important gateway course. As a preview, we carried out our study in an advanced multivariate calculus course that was geared for students interested in a science, technology, engineering or mathematics (STEM) career. We surmised that all students would correctly understand the need to maintain course content knowledge during their participation in the course to perform at a high level during exams. But once the class is over, a different story might arise. Students who go into their postcourse break (i.e., the summer) may see little need to reflect on and maintain memories that were threatening to their mathematics self-concept.
Additional alternative possibilities of the hypothesized motivated forgetting effect could be related to the amount of effort students put into the follow-up final exam given two weeks into the summer break. In general, we argue that individuals whose identity is threatened by their ongoing stress experience forget through a motivated process of inhibition that disrupts long-term memories related to the course content (i.e., a subtractive process that degrades retrieval strength; Erdelyi, 2006). However, students higher in ongoing stress and mathematics self-concept may simply not try as hard on the follow up assessment. Research on stereotype threat, for instance, documents that making stigmatized individuals aware of an existing negative stereotype can lead to reduced effort to perform (Schimel, Arndt, Banko, & Cook, 2004; Stone, 2002). Hence, we ask:
Lastly, students might avoid thoughts related to the course between the original exam and the follow-up final exam. This interpretation would implicate an avoidance strategy rather than inhibition as the cause of students’ reduced ability to retrieve memories during the follow-up exam. Thought avoidance is a hallmark of stress and anxiety (Andrews et al., 2010) and a common response to identity threat (Brodish & Devine, 2009; Chalabaev, Sarranzinr, Stone, & Cury, 2008; Seibt & Förster, 2004). In fact, some work has determined that threats to the self can produce spontaneous performance-avoidance goals that are capable of reducing interest in the domain (Smith, Sansone, & White, 2007) and even lead to disidentification with the domain (Osborne, 1997; Osborne & Walker, 2006).
In terms of motivated forgetting, there is previous support that long-term memory recall is impaired by both inhibitory processes that suppress information at retrieval (Anderson et al., 2004; Butler & James, 2010), as well as avoidance processes that replace unpleasant memories with other thoughts (Hertel & Calcaterra, 2005). It is possible that, once the course is over, students whose mathematics self-concept was previously at risk might avoid thoughts related to their unpleasant course experience by occupying their mind with less threatening thoughts and memories (i.e., an additive process that adds “noise” to the signal; Erdelyi, 2006). Avoiding thoughts related to unpleasant memories also holds the potential to deliberately change the mental context altogether (Manning et al., 2016; Sahakyan & Kelley, 2002), which could impair students’ ability to associate the previous course material with retrieval cues that are unique to the context after the course (i.e., the postcourse break). Hence, by measuring students’ avoidance of course-related thoughts, we address the degree to which students were aware that they were actively making an effort to avoid thinking of the classroom material and whether this process accounts for forgetting. In our last question, we ask:
In summary, we attempt to provide the first evidence for motivated forgetting of educationally relevant materials within a natural classroom setting. This work is important in opening a new window into understanding the dynamic interpersonal processes that impact students’ real-world retention of knowledge
Method
> <h31 id="edu-109-6-812-d56e447">Participants</h31>
We recruited students from an advanced multivariate calculus course at a large public university. The course is primarily offered to students who will enter STEM intensive fields that require comprehensive knowledge of advanced calculus. Four hundred students were enrolled in the course. Only
The study consisted of four stages: an initial entry survey, weekly text messages, the original final exam, and a final assessment that included the follow-up exam.
<bold>Stage I: Initial Entry Survey</bold>
During the first week of the 10-week course, students were asked to complete the initial Web survey that asked students to answer a Demographic Survey and complete a Mathematics Self Concept Questionnaire. During this time students were also given instructions on how to respond to weekly text messages that they would receive (which we outline below).
<bold>Demographic information</bold>
Considering the large diversity that exists within the public university setting of our sample, we asked students to report their mother and father’s level of education, completed from 1 (
<bold>Mathematics self-concept</bold>
We assessed students’ mathematics self-concept using a six-item survey that broadly measures self-perceptions related to mathematics and were borrowed from previous identity threat research (e.g., Aronson et al., 1999; Beilock, Rydell, & McConnell, 2007; Markus, 1977; Smith, & White, 2001; Spencer, Steele, & Quinn, 1999). The six items were: (a) It is important to me that I am good at mathematics; (b) I am good at mathematics; (c) I feel that I am good at thinking analytically about mathematics; (d) I feel like I have a good understanding of mathematics concepts; (e) Compared with others, I feel that I perform well in mathematics; and (f) Compared with others, I feel I understand mathematics well. Participants responded to the six items using a 7-point Likert scale, from 1 (
<bold>Ongoing stress</bold>
To get a measure of students’ ongoing stress, we asked students to respond to the following question:
<bold>Stage II: Weekly text message</bold>
Students were sent a weekly text message for the remaining 9 weeks of the course that assessed their current mathematics stress level (i.e., ongoing stress). The same question (“
<bold>Stage III: Final exam</bold>
During Week 11, the students who were still enrolled in the course were scheduled to take their final exam (referred to as the original final exam). The original final exam was cumulative and was built by the course instructor. The final exam was composed of 35 questions in a variety of formats (e.g., multiple choice, short answer, graph-equation matching, true-false). The combined set of items on the final exam showed weak internal consistency (Cronbach’s alpha = .64). This low consistency between items was to be expected given that the exam covered a wide range of topics and was not meant to focus on a single, converging concept. A sample exam item was, “The linear approximation
<bold>Stage IV: Final assessment</bold>
To allow sufficient time for student forgetting, we waited two weeks after the end of the course before emailing the students to complete the final assessment of the study. The email contained a link that directed students to the final assessment that was administered using an online platform for data collection (Collector;
Students were then asked to complete the
Results
> <h31 id="edu-109-6-812-d56e580">Student Background and Scoring</h31>
The majority of our student sample was 18–19 years of age (
Students responded to approximately 74.7% of the weekly text messages across the entire term and rated their average stress as moderate (
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For the original final exam score, we analyzed only the specific items that were present in the follow-up Exam as a proportion of the total possible. Proportion correct on the original final exam (
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Before turning to our main analyses, we checked basic model assumptions for multivariate linear regression. As seen in Table 1, the strength of the correlation between ongoing stress and mathematics self-concept (
We addressed our main research questions by conducting a series of simultaneous regression models using PROCESS (Hayes, 2013). Main effect predictors were all mean centered. A listwise deletion procedure was used to deal with missing data across our model variables.<anchor name="b-fn1"></anchor><sups>1</sups> We present the full results for the regression models in Table 2.
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><anchor name="tbl2"></anchor>
Our main moderation model (Model 1) evaluated whether average ongoing stress (the predictor variable) predicted forgetting rate (the primary outcome) and whether this relation was moderated by mathematics self-concept (the moderator variable) while controlling for SES (the control variable). The results for Model 1 revealed that the main effect of ongoing stress response and mathematics self-concept were not significant (
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One alternative account of the results presented in Model 1 is that students with a higher mathematics self-concept and more ongoing stress may have performed the best on the original final exam and hence had more room to forget during the follow-up exam. We evaluated this alternative account by running the same set of predictors as Model 1, but with original final exam performance as our outcome (Model 3). The coefficient for the main effect of mathematics self-concept was significant (
As stated earlier, our premise throughout the study is that students engage in a motivated forgetting process only once the class is over. Another way of providing evidence for this account is to predict students’ follow-up exam performance when individuals are sharing the same original final exam pretest score (i.e., entering original final exam score as a covariate in the model rather than using a subtraction method). In this model (Model 4), we found no evidence for a main effect of mathematics self-concept (
We also evaluated whether our results might be explained by the amount of effort students were exerting in the follow-up exam. Students higher in mathematics self-concept may have been exerting less effort on the follow-up exam as a function of ongoing stress. We addressed this alternative account by using the same predictors in Model 1 to predict self-reported effort. Results for Model 5 showed that neither the main effects or interaction were significant (
To evaluate this question, we turn to students’ self-reported tendency to avoid thinking about the course, which was measured during the follow-up assessment. In Model 6, we regressed students’ self-reported tendency to avoid thinking about the course on ongoing stress, mathematics self-concept, and the interaction of these two factors (controlling for SES). The main effect of ongoing stress was not significant (
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Our last model tested whether the Ongoing Stress × Mathematics Self-Concept interaction would remain a significant predictor of forgetting rate, even after we added students’ self-reported tendency to avoid thinking about the course as covariate. Our results for Model 7 revealed that the main effect of mathematics self-concept and ongoing stress response were not significant, but the interaction between students’ ongoing stress response and mathematics self-concept remained significant (
Discussion
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Students are commonly tasked with learning important course content under the duress of classroom stress (Centra, 2009; Hoyt & Lee, 2002; Jackson & Leffingwell, 1999; Perry, 2004). We argue that ongoing stress throughout a mathematics course can create a threat for students with a high mathematics self-concept, which triggers a motivation to forget course content. We found support for this argument by demonstrating that higher reported ongoing stress was associated with more pronounced forgetting among students with a higher mathematics self-concept. For students with lower mathematics self-concept, higher ongoing stress for the mathematics course did not relate to the amount of forgotten mathematics content at the end of the course (i.e., during the postcourse break).
Our interpretation follows quite clearly from the common tenets in the motivated forgetting literature, which argue that unpleasant experiences that threaten the self can lead to a real difficulty in bringing unpleasant memories to mind. A good deal of behavioral and neuroimaging evidence also suggests that individuals are quite adept at suppressing unwanted memories (Anderson & Green, 2001; Anderson et al., 2004; Benoit, Hulbert, Huddleston, & Anderson, 2015; Bjork & Bjork, 1996; Bjork, Bjork, & Anderson, 1998; Manning et al., 2016). We borrow from an identity threat framework to propose that students with high self perceptions of mathematics ability are likely threatened by course experiences that challenge that perception, which leads to adaptive processes meant to reduce accessibility of unpleasant memories.
Critically, we argue that even though students may be motivated to forget while they are enrolled in their course, they avoid doing so since the material is still highly relevant to their performance and course grade. But once the course is over, those with a higher mathematics self-concept and who feel threatened by their previous course experience may feel unconstrained and give in to the motivation to forget as a means of protecting their perceptions of mathematics ability.
Of course, there are several alternative accounts for why we observed the pattern of results we report. One account is that students with a higher mathematics self-concept and more ongoing stress might simply have more room to forget. In other words, this subgroup of students might have performed very well on the original final exam, which ironically leaves them vulnerable to forget more on the follow-up exam. The opposite might also be true. Students higher in mathematics self-concept, who experiences account or the deficient-encoding account.
Another alternative account for our results is that students who are higher in mathematics self-concept and ongoing stress may have exerted reduced effort during the follow-up exam relative to their student peers (Schimel, Arndt, Banko, & Cook, 2004; Stone, 2002). We did not find evidence in support of this effort account. The results of Model 5 revealed that neither the main effects nor the interaction of ongoing stress and mathematics self-concept were significant predictors of self-reported effort during the follow-up exam.
We have primarily argued that motivated forgetting is driven by a suppression process that makes threatening information less retrievable. Another possibility, however, is that avoidance rather than suppression is the cause of students’ reduced ability to retrieve memories. We examined this question by asking students how much they avoiding thinking about their mathematics course after the original final exam. We found that students with a higher mathematics self-concept who reported higher ongoing stress did, in fact, report that they avoided thinking about their mathematics course more than students with lower ongoing stress. The thought avoidance results suggest that students appear to have some awareness about their efforts to keep content outside of consciousness. Evidently students with a higher mathematics self-concept who do feel threatened (i.e., those who reported higher ongoing stress) not only forget more content, but also self-report avoidant thoughts about the course two weeks after the course is over.
Naturally one might wonder whether the forgetting results are explained by thought avoidance processes that, perhaps, make information less accessible. There are a number of possibilities by which thought avoidance could lead to greater forgetting. For instance, students who avoid thinking about (and retrieving) course relevant memories during their break could limit opportunities to associate their course memories with additional retrieval cues that are specific to the break context. Associating the course content solely with one context (i.e., the spring term) might reduce the match in retrieval cues that students draw upon during the follow-up exam (i.e., the summer term) and hence lead to difficulties in recall (Sahakyan & Kelley, 2002). It is also possible that avoiding thoughts related to the course could have been carried out by occupying one’s mind with alternative thoughts and memories that disrupt long-term memory retrieval (Anderson et al., 2004; Benoit & Anderson, 2012; Butler & James, 2010).
While a number of reasons might explain why thought avoidance can lead to forgetting, we found that thought avoidance did not explain the forgetting effects in our study. In fact, we found that across the entire sample, students’ self-reported tendency to avoid thinking about the course did not correlate with students’ forgetting rate,
A major limitation in this work is the correlational nature of our design that prevents us from making causal claims about the effects of ongoing stress on students’ forgetting rates. The decision to conduct a correlational study was intentional, as examining motivated forgetting among STEM students allowed us to leverage the real-life variation in mathematics self-concept and weekly classroom stress that might predict forgetting.
Our focus in studying real-life course forgetting via exam performance also limited us in a number of other ways. For instance, the original final exam constructed by the course professor showed weak internal consistency. One possible explanation for the low internal consistency is that the course covered over 10 different topics (i.e., limits and continuity, calculus of vector value functions, gradient and directional derivatives, chain rule ad optimization, etc.) and each exam question incorporated 2 to 3 topics. This is not typical of other scales that focus on single psychological concepts. We were also limited by our decision to omit some final exam items during the follow up exam in an effort to keep the exam short and reduce student dropout. Similarly, we chose to only administer true-false and multiple-choice items, which limits the effects to recognition rather than recall processes. Prior work has found weaker forgetting effects on recognition compared with recall tests (Basden, Basden, & Gargano, 1993; Geiselman, Bjork, & Fishman, 1983; Gross, Barresi, & Smith, 1970; Wetzel, 1975), suggesting that our choice of materials on the follow-up exam may have made memory retrieval easier. It is also the case that readministering the 16 items from the original final exam on the follow-up exam builds in a test-retest effect that might underestimate the rate of forgetting. One way we could have avoided the inflation of scores because of previous testing is to form a new follow-up exam on the same concepts tested in the original final exam. However, following this line of logic makes the forgetting rate effects even more noteworthy because the recognition tests used for both the original final exam and the follow-up exam should have minimized the detection of such motivated forgetting effects.
Finally, we acknowledge that this study could have been strengthened if we had employed a separate measure of course performance outside of the final exam. However, we did not ask students for permission to obtain their course grades because we wanted to make the study minimally intrusive.
<h31 id="edu-109-6-812-d56e873">Educational Implications and Recommendations</h31>Our results suggest that threatening classroom experiences may lead students to employ defense adaptations that unintentionally impair memory for important course content. These defensive adaptations need to be addressed, possibly through interventions, to help students better cope with threats to their identity. For instance, it has been reported that threatening academic experiences can lead to a distortion in students’ perceptions of previous mathematics performance and ability (Necka, Sokilowski, & Lyons, 2015), as well as disidentification and reduced interest in a domain of study (Steele, James, & Barnett, 2002). If threats to the self are indeed what underlie motivated forgetting in the classroom, then ensuring that students
Of course, it is important to also give students the social-emotional skills to better understand and cope with ongoing stress as well. One promising method is to help students endorse a perspective that looks at stress (Crum, Salovey, & Achor, 2013), and failure more broadly (Haimovitz & Dweck, 2016), as an enhancing rather than as a threatening force. Prior work finds that reframing the physiological stress response as beneficial can lead to enhanced performance on standardized exams and school assignments (Jamieson, Mendes, & Nock, 2013). Students who approach classroom stress as a normal challenge that is a part of the learning process rather than a threat to their self-perception may have the appropriate appraisal perspective to minimize motivated forgetting in the classroom.
The work reported here also makes important recommendations for educators to be aware of the various educational practices that encourage forgetting. School systems and instructors widely engage in a host of classroom practices that create implicit cues to forget important classroom content, which may be exacerbated by the students’ own motivation to forget.
At the level of the school system, the postcourse break (especially during the summer) is a time that provides a strong cue for students to forget what they have learned during the previous term. In fact, summer break has been identified as a period that is associated with profound forgetting because of a lack of educationally enriching activities (Cooper et al., 1996). However, the summer period may also lead to forgetting because it cues sharp event boundaries. Research on event cognition and memory (Kurby & Zacks, 2008) argues that memories for events that make up our daily life are segmented to have a beginning and an end, such that when people pass from one event to another, they forget more information than if they had not made such a shift (Radvansky & Copeland, 2006; Radvansky, Krawietz, & Tamplin, 2011). Summer break provides a concrete event boundary by which students might be cued to forget an unpleasant course experience. If this is the case, then extending mathematics activities into the summer could help to diffuse the event boundary between the school year and summer term and improve the retention of course content (Bahrick & Hall, 1991).
At the instructor level, pedagogical decisions impact rates of forgetting. For instance, classrooms that rely on a linear versus a spiral curriculum (Bunce, VandenPlas, & Soulis, 2011) and those in which instructors teach in a more traditional as opposed to inquiry-oriented manner (Kwon, Rasmussen, & Allen Keene, 2005) lead to greater difficulties in recalling STEM knowledge after the passage of time. Students also appear to search for reasons to retain content memories. A common student query is, “Why am I learning this?” which reflects the need to convey to students the importance of content. If answered appropriately, the students’ need for relevance could go a long way in better promoting knowledge retention. For example, STEM textbooks that use applications to introduce and motivate a concept or skill result in greater retention of conceptual knowledge (Garner & Garner, 2001).
In addition, the presentation of blocked practice problems within mathematics textbooks (Rohrer & Taylor, 2007), as well as use of noncumulative examinations (Khanna, Brack, & Finken, 2013; Lawrence, 2013) are practices that also lead to greater forgetting. The aforementioned practices may lead to greater forgetting, in part, because they communicate that previously covered content no longer holds any relevance for future classroom performance.
Anecdotally, it seems like testing (cumulative or not) is a common source of ongoing stress for many students that could tempt educators to reduce testing altogether. Yet distributed testing actually seems to reduce testing-related stress (Agarwal, D’Antonio, Roediger, McDermott, & McDaniel, 2014; Crooks, 1988; Dempster, 1992; Dustin, 1971; Szpunar, Khan, & Schacter, 2013) and promote long-term knowledge retention (McDaniel, Anderson, Derbish, & Morrisette, 2007; Roediger & Karpicke, 2006). Hence, when tests are used as a learning tool, more rather than less testing may give teachers one promising avenue by which to improve knowledge retention and reduce ongoing stress that contributes to motivated forgetting.
At the student level, we suspect that particular study practices such as taking photographs of classroom PowerPoint slides (Henkel, 2014) or taking long-hand notes on a laptop during lectures (Mueller & Oppenheimer, 2014) have the potential to encourage forgetting as well. These practices lead students to expect that they will have future access to the information and do not need to maintain a strong memory representation (Sparrow, Liu, & Wegner, 2011).
Our work contributes to ongoing discussions around whether the forgetting process that underlies motivated forgetting is largely carried out as a result of students’ conscious efforts to suppress threatening information or whether this process occurs below conscious awareness. Indeed, there is a lively ongoing debate (Brewin & Andrews, 2014; Handy, 2015; Patihis, Ho, Tingen, Lilienfeld, & Loftus, 2014) about whether motivated forgetting is best explained by controlled conscious processes (i.e., suppression) or processes outside of conscious awareness (i.e., repression; Epstein, 1994; Freud, 1937), with others suggesting that repression and suppression are largely the same thing (Erdelyi, 2006). Our forgetting results highlight that students may forget the mathematics course content despite being aware that this content will be relevant in their future studies. The thought avoidance results suggest that this motivated forgetting process is also paired with a conscious effort to avoid bringing threatening content to mind. We hope that the work reported here will stimulate this ongoing discussion on whether motivated forgetting is a process that is largely outside of conscious awareness, by providing an example of motivated forgetting within a natural classroom field setting.
Conclusion
>
The ability to retain learned material in a course is critical to excel in related courses and to succeed in a work environment that depends on those learned skills and knowledge. We provide the first evidence of a self-directed motivation that jeopardizes long-term retention of course material in a real-world educational context. Students with a high self-concept related to the course topic and ongoing course-related stress are at the greatest risk for forgetting that material. Future work aimed at supporting long-term retention of course material is critical for this group of students who, ironically, are most in need of retaining the material for future STEM courses and careers.
Footnotes
<anchor name="fn1"></anchor><sups> 1 </sups> There were 1–4 missing cases for each of our model predictors and outcome variables (<5% of the data for each respective variable). The results did not change when a mean imputation procedure was used instead to account for missing data.
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