Motivation and emotion/Book/2015/Zeigarnik effect

From Wikiversity
Jump to navigation Jump to search
Zeigarnik effect:
How does the Zeigarnik effect affect motivation?


Figure 1. An unfinished puzzle creates motivation to complete
Figure 2. An unfinished task is remembered better than a completed one (Zeigarnik, 1938).

Overview[edit]

Have you ever been kept awake at night remembering details about a project that you haven't finished? Does your mind keep going over items on your to do list? With exams, do you vividly remember that question you just couldn’t answer? If you said yes to any of these questions then you might be experiencing the Zeigarnik effect. That is you might be having persistent memories or intrusive thoughts about activities that are incomplete in your mind (Schiffman & Greist-Bousquet, 1992).

What is the Zeigarnik effect?[edit]

The Zeigarnik effect finds that recall or memory of a task occurs more readily when the task is incomplete or interrupted (Zeigarnik, 1938). The Zeigarnik effect is named for the woman who discovered it, Bluma Zeigarnik, a Russian psychologist influenced strongly by the principles of Gestalt Psychology and the Berlin School of experimental psychology (Roeckelein, 2006).   In her classic experiment, Zeigarnik (1938) gave subjects 20 tasks to complete, manual tasks such as constructing clay figurines and mental tasks such as arithmetic puzzles (Seifert & Patalano, 1991) and in half the activities subjects were interrupted before completion.  Zeigarnik subsequently administered a free recall test and found that almost twice as many of the incomplete tasks were remembered. The Zeigarnik effect has been replicated more recently by Seifert & Patalano (1991).  

Earworms - You know those songs that sometimes get stuck in your head? The reason may be partially related to the Zeigarnik effect, perhaps because when you hear a snippet of a song it remains incomplete and thus it persists in your mind (Hyman et al., 2013)

How can the Zeigarnik effect be motivating?[edit]

If the Zeigarnik effect is primarily related to improved memory recall for incomplete tasks, then how is the effect related to motivation? This is a good question, because although the Zeigarnik phenomenon is well explained in literature it is not particularly well understood in terms of motivation (Savitsky, Medvec, & Gilovich, 1997; Stafford, 2012).  

Zeigarnik (1938) and her colleague Maria Rickers-Ovsiankina observed that there was a very strong relationship between the desire to finish the interrupted activity and the memory for the incomplete task (Farina, 1996; Koffka, 1935; Prentice, 1944).  This was shown in two ways, through a general resistance to being interrupted, and a tendency to resume tasks once able (Koffka, 1935; McGraw & Jirina, 1982; Zeigarnik, 1938).  Zeigarnik proposed that the memory advantage for unfulfilled tasks was an outcome of the tension created from the interruption, in doing so she drew on Gestalt psychology and the law of closure (Barlow, 1981).

It was actually Maria Rickers-Ovsiankina who studied the tendency for people to return to an interrupted task (Farina, 1996; Prentice, 1944).  The Ovsiankina effect which describes this phenomenon is considered to be a manifestation of the Zeigarnik effect (McGraw & Jirina, 1982).

Historical basis[edit]

Figure 3. Law of closure - objects grouped together are seen as whole (Koffka, 1935).

Gestalt psychology[edit]

The Zeigarnik effect has its roots in early Gestalt psychology, which has a fundamental focus on holism, or the idea that the mind is focused on representing a whole form rather than seeing sub-elements (Wertheimer, 1938).

The influential Gestalt school of thought arose in Berlin in the early twentieth century and was considered revolutionary at the time by moving away from structuralism's focus on breaking things down into component parts (Wagemans et al., 2012). The Gestalt psychologists developed a core set of laws to explain how the concept of the 'whole' manifests, these laws are known as the principles of perceptual grouping (Wagemans et al., 2012). Gestalt psychology declined in influence post World War II, but many of the key concepts continue to have relevance in the world today (Wagemans, et al., 2012). In fact the well-known expression ‘the whole is greater than the sum of its parts’ is based on the Gestalt principles (Barlow, 1981; Helson, 1933).

Music film clapperboard.svg
Click here to observe closure in music - Bobby McFerrin at the World Science festival in 2009

Law of closure[edit]

The law of closure is one of the principles of perceptual grouping and describes the tendency to see groups of points or shapes as regular forms (Koffka, 1935). Although predominantly related to visual perceptions, early Gestalt psychologists extended the law to describe mental experiences, in that the mind is strongly motivated to reach closure of thought, and that lack of mental closure causes frustration and a strong impetus towards completion (Barlow, 1981).  

Field theory, tension and quasi-needs[edit]

Zeigarnik was a protégé of Kurt Lewin, another Gestalt psychologist who went on to contribute a significant legacy with field theory (Tolbert, 2004). Lewin is considered to be the person who integrated Gestalt with motivational concepts (Wagemans, et al., 2012), and the Zeigarnik effect was early proof that Lewin’s ideas had merit (Tolbert, 2004).

A key tenet of field theory, which extends Gestalt holistic perspectives into the study of motivation, says that behavior is a integration between a person and their psychological environment and that it is this integration which determines behaviour (Lewin, 1938; Weiner, 1992).

Lewin (1938) asserted that all psychological processes tend towards equilibrium and devised the motivational concept of tension. He suggested that tension is created when needs or intentions arise and motivate behaviour until the need is satisfied (Roeckelein, 2006; Weiner, 1992). Zeigarnik (1938) drew on Lewin's work to explain that when a task is started it creates a “quasi-need” (p. 296) for completion such that when the task is interrupted the person remains in a state of tension until the task is resolved. Lewin explained the quasi-need as a psychological intention with similar motivational properties to other physiological needs.

Zeigarnik (1938) explains that this tension creates enhanced memory for incomplete tasks, which is maintained until completion or resolution. A further implication being that the same tension motivates resumption behaviour, and thus the observable Zeigarnik effect of persistent memory or attentional focus for a task is a proxy measure of motivation (Prentice, 1944).

Related theoretical models[edit]

The Zeigarnik effect was an early demonstration of field theory and inspired a range of later motivational concepts (Tolbert, 2004). Subsequent research in achievement motivation (Atkinson, 1953), competence motivation (White, 1959), cognitive dissonance theory (Festinger, 1962), the need for psychological closure (Webster & Kruglanski, 1994) and the concept of intrinsic motivation (Deci & Ryan, 1985) all built on the Gestalt concepts in an attempt to explain the natural human motivation to cognitively engage and persist with tasks until completion (Roeckelein, 2006).   By examining each of these motivational constructs it becomes easier to see how the memory and recall enhancing attributes of the Zeigarnik effect correlate with or support other theories of motivation. 

Need for achievement[edit]

Figure 4. NASA Exceptional Achievement Medal - demonstrates the value placed on the concept of achievement.

Much literature has been published about the human need for achievement, seeking to understand and explain the basis of motivation (Cooper, 1983; Elliot & Dweck, 2005).  Early research by Atkinson (1953) studied both the need for achievement and the Zeigarnik effect, finding some linkage which was later reproduced by Cooper (1983). Atkinson found that individual’s with high achievement motive tended to recall incomplete tasks rather than completed ones, he also found some contradictory evidence as the effect was opposite with people low in achievement motivation.  Atkinson later drew on the Zeigarnik effect to say that once a motivation has been established it will persist until resolved (Atkinson, 1964 as cited in Revelle & Michaels, 1976).

Competence motivation[edit]

The early research into the need for achievement was focused predominantly on classroom, sports and workplace contexts (Elliot & Dweck, 2005).  Elliot and Dweck (2005) extended beyond this with their focus on competence and suggested that in fact motivation to achieve competence extends more broadly in everyday life.

Competence is considered a basic psychological need to operate effectively in the world (White, 1959).  The need for competence motivates people to test themselves, build skills, make progress and complete tasks (Elliot & Dweck, 2005).  White (1959) proposed that people feel a sense of satisfaction from competence and are motivated to seek out and persist with challenges until they are achieved. This motivation for competence has correlation with Lewin’s (1938) concept of ‘quasi-needs’ as motivators for satisfaction from closure (Elliot & Dweck, 2005) and Zeigarnik’s (1938) finding that interruption prevents this satisfaction.

Figure 5. Mozart
Mozart and closure - It may be apocryphal, but the following story about Mozart illustrates cognitive dissonance and the need for closure. Once a friend was visiting and Mozart would not get out of bed to receive him. So the friend played a piano concerto stopping part way. Apparently Mozart got out of bed to complete the piece, unable to leave the music unfinished (Goldstein, 2013)

Cognitive dissonance[edit]

Cognitive dissonance is the psychological discomfort felt when beliefs, attitudes or behaviours are incongruent or conflicting (Festinger, 1962), and can be extended to when expectations are not met (Aronson, 1968, as cited in, Beck, 2003). Cognitive dissonance is a strong motivator as people generally seek to reduce their discomfort (Festinger, 1962).

An interruption when undertaking a task creates a kind of dissonance, as the expectation of completion goes unmet (Elliot & Devine, 1994; Roeckelein, 2006). Festinger (1962) explained that dissonance acts motivationally in a similar way to needs or tension.  This explanation indicates a possibility the Zeigarnik effect also arises as a dissonance reduction activity (Wicklund & Brehm, 1976).

Cognitive closure[edit]

The need for cognitive closure is described as the motivating desire to achieve a definitive answer to some pending question (Kruglanski & Webster, 1996).  The need for closure can be understood as two distinct ideas, specific closure, which has a focus on receiving a desired answer, as contrasted with non-specific closure, where the desire is for any answer that will remove confusion or uncertainty (Kruglanski & Webster, 1996; Webster & Kruglanski, 1994). The need for non-specific cognitive closure tends to encourage and bias individuals towards those activities and choices which provide some or any resolution (Houghton & Grewal, 2000). 

Comedyfilm.png
Watch an amusing video demonstrating the powerful need for closure and the tendency to resume incomplete activities.

The need for closure is considered a personality trait with some people having a higher need for closure than others, which can be enhanced or reduced in different situations (Beck, 2003; Webster & Kruglanski, 1994). The Zeigarnik effect may contribute to the need for cognitive closure by creating a persistent attentional focus on unresolved scenarios or questions (Hammadi & Qureishi, 2013).  The need for cognitive closure can have a significant impact on how much time and effort people take to make decisions, and someone with high cognitive closure requires less information and is less likely to change once a decision has been made (Houghton & Grewal, 2000).  Because this need for closure can be situational (Beck, 2003; Webster & Kruglanski, 1994) the implication is that the Zeigarnik effect, aroused by interruptions, influences decision making behaviour. This certainly holds true for consumer attention (Hammadi & Qureishi, 2013).

Intrinsic motivation[edit]

Intrinsic motivation is described as an inherent need for competence and self-determination (Deci & Ryan, 1985). One characteristic of intrinsic motivation is that people are inclined to seek out and engage in interesting activities and that they are naturally persistent when attempting to conquer optimal (not too easy or too hard) challenges (Deci & Ryan, 1985).  A study into the effect of reward on the Zeigarnik effect, made claim that the two phenomenon may actually be one and the same, and that intrinsic motivation is actually a manifestation of the Zeigarnik effect (McGraw & Jirina, 1982).  However on further examination, researchers have demonstrated that this is not the case by showing that parameters which enhance intrinsic motivation, such as self-efficacious feedback, override the Zeigarnik effect (Reeve, Cole, & Olson, 1986).

Exploitation of the Zeigarnik effect[edit]

Figure 6. The Pickwick Papers was an early example of the motivational power of a cliffhanger

Inividuals may have personally experienced the Zeigarnik effect in daily life as it is often apparent in the entertainment and advertising fields as a technique to attract and engage audiences. The following examples might help to recognise the Zeigarnik effect being used to influence behaviour.

The cliffhanger[edit]

The cliffhanger is a well known usage of the Zeigarnik effect. The very effective plot device is often used in entertainment to create a sense of suspense at the end of serialised work, chapters of books, television episodes and films. By leaving readers or viewers with a feeling of incompleteness the intent is to motivate the audience to return for the next installment (Baranowski, Buday, Thompson, & Baranowski, 2008).

Charles Dickens may have been one of the early adopters of the cliffhanger in his novel The Pickwick Papers. Originally published as serialised chapters once or twice a month, his stories always ended with characters in perilous situations (Austin, 2011).  A modern version is the serialised television show, with Australian soap-operas being particularly known for using the cliffhanger to entice viewers to return for the next episode.

Consumer purchase motivation[edit]

Another field in which the Zeigarnik effect is leveraged is marketing.  The power of the Zeigarnik effect is used to influence purchasing behaviour, by creating attentional focus and memory for brand or product (Hammadi & Qureishi, 2013) and promoting the need for closure in relation to consumer decision making (Houghton & Grewal, 2000; Kupor, Reich, & Shiv, 2015; Liu, 2008; Niculescu, Payne, & Luna‐Nevarez, 2014). Purchase motivation at point of sale can be impacted by interruptions which strongly influence consumer purchasing behaviour and the urgency for closure (Niculescu, et al., 2014), with consumers interrupted during transactions likely to reduce the number of options examined (Kupor, et al., 2015) and tend towards higher risk or higher priced purchasing preferences such as luxury goods (Liu, 2008). 

Pringles logo.png
A Cannes Lions 2009 award-winning advertisement, the Pringles Can Hands Banner Advertisement uses the Zeigarnik effect to keep attention.

Advertising[edit]

Some advertising leverages the Zeigarnik effect to grab consumer attention and create persistant memories of a particular brand (Hammadi & Qureishi, 2013).  There is strong evidence that the Zeigarnik effect arises with interruptions of advertising material (Heimbach & Jacoby, 1972).  For example, when television commercial is stopped part way through there is an increased residual memory for the advertisement and awareness of the advertised brand (Heimbach & Jacoby, 1972). Another way is through the introduction of foreign words, this is effective because the unexpected nature of the foreign word creates a cognitive interruption, a motivation to decipher the foreign word and a memory increase for the advertisement (Domzal, Hunt, & Kernan, 1995),   

Online advertising also deploys the Zeigarnik effect regularly, with advertisements often presenting only partial information requiring the viewer to click in order to find out the rest of the information (Joyner, 2001).

Media and clickbait headlines[edit]

Figure 7. Clickbait - Online advertising uses the Zeigarnik effect to entice clicks

Other avid Zeigarnik effect exploiters are online news outlets, especially tabloid, social media and commercial media, which are renowned for using clickbait headlines (Blom & Hansen, 2015; Shire, 2014).  Clickbait headlines are designed to leave unanswered questions by only partially revealing the content of an article, in doing this they establish an unfulfilled goal which entices readers to click (Ifantidou, 2009).  The clickbait headline has increased in prevalence as news industry moves away from print to the online environment and advertising revenue is based on numbers of clicks not number of paper copies sold, meaning journalists need readers to actively click to read (Blom & Hansen, 2015).

Social media engagement[edit]

The compelling nature of social media platforms such as Twitter and Reddit may also relate to the Zeigarnik effect, as incomplete snippets of information are shared continually and create a sense of perpetually unfinished thought or issue (Tam & Walter, 2013)

Video game design[edit]

The video gaming industry is hugely profitable and competitive (Tam & Walter, 2013), and there is significant effort expended to design games that both motivate purchase, and also keep players participating (Murphy, Chertoff, Guerrero, & Moffitt, 2014; Tam & Walter, 2013). 

One key game design feature, which draws on the Zeigarnik effect and the need for closure, is the concept of the unfinished task list (Murphy, et al., 2014). Games incorporate the idea of an unfinished task in numerous ways, sometimes in the form of an overall story quest (Dickey, 2007), repeated mini tasks (Dickey, 2005), a more simple a to-do list (Murphy, et al., 2014) or even a repetitive cycle of pattern matching (Stafford, 2012). Whatever the technique chosen the game designers are creating an environment in which the Zeigarnik effect is induced and players are motivated to continue playing the game.     

Tetris[edit]

Emacs Tetris vector based detail.svg
The Zeigarnik effect can also be observed in the popular early computer game, Tetris (Stafford, 2012).  In this addictive falling block game, the main aim is to complete rows of blocks. The shape of the blocks inevitably means that as you complete one row, another commences.

Minecraft[edit]

Minecraft cube.svg

One enormously popular game, Minecraft has become extremely successful by allowing for an unlimited universe in which players create their own goals, to a certain extent this is the ultimate incomplete task (Murphy, et al., 2014)

A tool for personal motivation[edit]

Figure 8. The Zeigarnik effect can help remember unfinished tasks on a to-do list

Although it may appear the main impact of the Zeigarnik effect on people is to allow manipulation by sales people and the entertainment industry, this doesn’t mean that it isn’t relevant in everyday life (Seifert & Patalano, 1991).  Interruptions are an universal experience and the rate of interruption in life is increasing with text messages, mobile phones, email and social media (Kupor, Reich, & Shiv, 2015).   It is possible that the Zeigarnik effect’s memory enhancement is an adaptive strategy which can be leveraged to enhance personal motivation and, by learning from mistakes, reduce future failures (Seifert & Patalano, 1991). 

Memory and memory cues[edit]

The Zeigarnik effect has a similar effect on prospective memory as it does on retrospective memory, in that it is easier to remember to do an outstanding task (Mäntylä & Sgaramella, 1997). For example it is not important to remember those items on a shopping list that you have already purchased, remembering only outstanding items appears much more useful (Seifert & Patalano, 1991). This focus on unfinished tasks may reduce the memory accessibility for completed tasks which in turn increases cognitive capacity for other tasks (Touré-Tillery & Fishbach, 2014). 

Learning and studying[edit]

Students may have observed the Zeigarnik effect for themselves after participating in exams when they find unanswered questions the easiest to recall (Schiffman & Greist-Bousquet, 1992).   There are several ways the Zeigarnik effect might be useful as a tool to enhance learning habits and motivation for study.

Table 1 Ideas for leveraging the Zeigarnik effect to support learning
Avoid procrastination by just getting started

The act of starting your study may encourage the Zeigarnik effect to kick in after you stop, and thereby motivate you to return to your study (Touré-Tillery & Fishbach, 2014).

Study for short periods and take regular breaks

Interrupting your study flow may mean the Zeigarnik effect improves your recall for the topic (Touré-Tillery & Fishbach, 2014).

Write your own quiz questions before studying

Writing out your own unanswered quiz questions may create an unfinished task, with the resultant Zeigarnik effect motivating you to find out the answers (Hiramatsu, Ito, Fujii, & Sato, 2014)

When the Zeigarnik effect goes wrong[edit]

Figure 9. Problem internet usage may be related to the Zeigarnik effect (Tam & Walter, 2013).

There is evidence that the Zeigarnik effect isn’t universally productive and may be associated with intrusive thoughts and chronic long held feelings of regret (Savitsky, et al., 1997).   

Savitsky, et al. (1997), studied the tendency that people have for regret, and found that regretful memories for past inactions were greater and more prevalent than the regrets for actions.  Savitsky proposed that the Zeigarnik effect was preserving the memory of regret from inaction.  One learning from this may be that when faced with options, taking action may be ultimately preferable and less likely to become an eternally regretted unfinished issue (Savitsky, et al., 1997).

Another example of the negative impact of the Zeigarnik effect can be seen with problem internet usage, which has become more prevalent with the growth of internet based social networking and online gaming (Tam & Walter, 2013).  Those same characteristics of the Zeigarnik effect which make internet usage and video gaming compelling (Murphy, et al., 2014) can also keep people engaged even when it is becoming unhealthy for them (Tam & Walter, 2013).  Issues like problem online gambling and addictive video gaming are correlated with deleterious effects to relationships, mental and physical health issues with some reports from Japan claiming young male deaths from incessant online gaming (Tam & Walter, 2013).

Zeigarnik effect limitations[edit]

There does appear to be some limitation to the Zeigarnik effect.  Individual differences have been observed, and those with low need for achievement experience less of the Zeigarnik effect (Atkinson, 1953). McGraw and Jirina (1982) also found that expectations of reward undermined the Zeigarnik effect by almost half. The effects of intrinsic motivation can also override the Zeigarnik effect (Reeve, et al., 1986).  These limitations indicate that the Zeigarnik effect might not be a universally powerful motivator.

Conclusion[edit]

Despite years of research and examination, much is unknown about the Zeigarnik effect (Savitsky, et al., 1997) and the underlying mechanisms are not well understood (Mäntylä & Sgaramella, 1997; Stafford, 2012). There is little research examining the Zeigarnik effect in a contempory setting, and yet interruptions are an increasingly prevalent experience in modern life so it appears that this area of study is still relevant today.  

Perhaps the real irony of the Zeigarnik effect is that the phenomenon, which explains the memory implications of unfinished tasks, itself remains largely unresolved.

See also[edit]

References[edit]

Atkinson, J. W. (1953). The achievement motive and recall of interrupted and completed tasks. Journal of Experimental Psychology, 46(6), 381-390. doi: 10.1037/h0057286

Austin, M. (2011). Useful fictions: Evolution, anxiety, and the origins of literature: University of Nebraska Press.

Baranowski, T., Buday, R., Thompson, D. I., & Baranowski, J. (2008). Playing for real: video games and stories for health-related behavior change. American journal of preventive medicine, 34(1), 74-82. e10.

Barlow, A. (1981). Gestalt-antecedent influence or historical accident. The Gestalt Journal, 4(2), 35-54. Retrieved from http://www.gestalt.org/barlow.htm

Beck, R. C. (2003). Motivation: Theories and principles (4 ed.). New Jersey: Prentice Hall.

Blom, J. N., & Hansen, K. R. (2015). Click bait: Forward-reference as lure in online news headlines. Journal of Pragmatics, 76, 87-100. doi: http://dx.doi.org/10.1016/j.pragma.2014.11.010

Cooper, W. H. (1983). An achievement motivation nomological network. Journal of Personality and Social Psychology, 44(4), 841-861. doi: 10.1037/0022-3514.44.4.841

Deci, E. L., & Ryan, R. M. (1985). Intrinsic motivation and self-determination in human behavior. New York: Plenum Press.

Dickey, M. D. (2005). Engaging by design: How engagement strategies in popular computer and video games can inform instructional design. Educational Technology Research and Development, 53(2), 67-83.

Dickey, M. D. (2007). Game design and learning: A conjectural analysis of how massively multiple online role-playing games (MMORPGs) foster intrinsic motivation. Educational Technology Research and Development, 55(3), 253-273.

Domzal, T. J., Hunt, J. M., & Kernan, J. B. (1995). Achtung! The information processing of foreign words in advertising. International Journal of Advertising, 14(2), 95-114.

Elliot, A. J., & Devine, P. G. (1994). On the motivational nature of cognitive dissonance: Dissonance as psychological discomfort. Journal of Personality and Social Psychology, 67(3), 382-394. doi:10.1037/00223514.67.3.382

Elliot, A. J., & Dweck, C. S. (2005). Competence and motivation: Competence as the core of achievement motivation. In A. J. Elliot, & C. S. Dweck (Eds.), Handbook of competence and motivation (pp. 3–12). London: Guilford Press.

Farina, A. (1996). Maria Rickers-Ovsiankina (1898–1993): Obituary. American Psychologist, 51(6), 650-650. doi: 10.1037/0003-066X.51.6.650

Festinger, L. (1962). A theory of cognitive dissonance. Stanford, California: Stanford University Press.

Goldstein, J. (2013). 101 Amazing Mozart Facts: Andrews UK Limited.

Hammadi, A., & Qureishi, F. K. (2013). Relationship between the Zeigarnik effect and consumer attention in advertisement. World, 3(4).

Heimbach, J. T., & Jacoby, J. (1972). The Zeigarnik effect in advertising. In M. Venkatesan (Ed.), Proceedings of the Third Annual Conference of the Association for Consumer Research (pp. 746-758). Chicago, IL: Association for Consumer Research.  

Helson, H. (1933). The fundamental propositions of Gestalt psychology. Psychological Review, 40(1), 13.

Hiramatsu, Y., Ito, A., Fujii, M., & Sato, F. (2014). Development of the learning system for outdoor study using Zeigarnik effect. In P. Zaphiris & A. Ioannou (Eds.), Learning and Collaboration Technologies. Technology-Rich Environments for Learning and Collaboration (Vol. 8524, pp. 127-137): Springer International Publishing. Retrieved from http://dx.doi.org/10.1007/978-3-319-07485-6_13

Houghton, D. C., & Grewal, R. (2000). Please, let's get an answer—any answer: Need for consumer cognitive closure. Psychology & Marketing, 17(11), 911-934.

Hyman, I. E., Burland, N. K., Duskin, H. M., Cook, M. C., Roy, C. M., McGrath, J. C., & Roundhill, R. F. (2013). Going Gaga: Investigating, creating, and manipulating the song stuck in my head. Applied Cognitive Psychology, 27(2), 204-215. doi: 10.1002/acp.2897

Ifantidou, E. (2009). Newspaper headlines and relevance: Ad hoc concepts in ad hoc contexts. Journal of Pragmatics, 41(4), 699-720.

Joyner, M. (2001). The confidential internet intelligence manuscript. Newport News, VA: Morgan James Pub.

Koffka, K. (1935). Principles of Gestalt psychology (Vol. 44): Routledge.

Kruglanski, A. W., & Webster, D. M. (1996). Motivated closing of the mind: "Seizing" and "freezing". Psychological review, 103(2), 263.

Kupor, D. M., Reich, T., & Shiv, B. (2015). Can't finish what you started? The effect of climactic interruption on behavior. Journal of Consumer Psychology, 25(1), 113-119. doi: http://dx.doi.org/10.1016/j.jcps.2014.05.006

Lewin, K. (1938). Wills and needs. In W. D. Ellis (Ed.), A source book of Gestalt psychology (pp. 283-299). London: Routledge & Kegan Paul Ltd. 

Liu, W. (2008). Focusing on desirability: The effect of decision interruption and suspension on preferences. Journal of Consumer Research, 35(4), 640-652. doi: 10.1086/592126

Mäntylä, T., & Sgaramella, T. (1997). Interrupting intentions: Zeigarnik-like effects in prospective memory. Psychological Research, 60(3), 192-199. doi: 10.1007/BF00419767

McGraw, K. O., & Jirina, F. (1982). Undermining the Zeigarnik effect: Another hidden cost of reward. Journal of Personality, 50(1), 58. doi: 10.1111/1467-6494.ep7380376

Murphy, C., Chertoff, D., Guerrero, M., & Moffitt, K. (2014). Design better games: flow, motivation, and fun. In S. Coleman & T. Hussain (Eds.), Design and Development of Training Games: Practical Guidelines from a Multidisciplinary Perspective (pp. 146-178).

Niculescu, M., Payne, C. R., & Luna‐Nevarez, C. (2014). Consumer response to interruption features and need for cognitive closure. Journal of Consumer Behaviour, 13(1), 60-72.

Prentice, W. (1944). The interruption of tasks. Psychological Review, 51(6), 329.

Reeve, J., Cole, S., & Olson, B. (1986). The Zeigarnik effect and intrinsic motivation: Are they the same? Motivation and Emotion, 10(3), 233-245. doi: 10.1007/BF00992318

Revelle, W., & Michaels, E. J. (1976). The theory of achievement motivation revisited: The implications of inertial tendencies. Psychological Review, 83(5), 394.

Roeckelein, J. E. (2006). Elsevier's dictionary of psychological theories: Elsevier.

Savitsky, K., Medvec, V. H., & Gilovich, T. (1997). Remembering and regretting: The Zeigarnik effect and the cognitive availability of regrettable actions and inactions. Personality and Social Psychology Bulletin, 23(3), 248-257.

Schiffman, N., & Greist-Bousquet, S. (1992). The effect of task interruption and closure on perceived duration. Bulletin of the Psychonomic Society, 30(1), 9-11.

Seifert, C. M., & Patalano, A. L. (1991). Memory for incomplete tasks: A re-examination of the Zeigarnik effect. In Proceedings of the Thirteenth Annual Conference of the Cognitive Science Society (pp. 114-119). Mahwah, NJ: Erlbaum.

Shire, E. (2014). Saving us from ourselves: The anti-clickbait movement. The Daily Beast. Retrieved from http://www.thedailybeast.com/articles/2014/07/14/saving-us-from-ourselves-the-anti-clickbait-movement.html

Stafford, T. (2012). The psychology of Tetris. BBC. Retrieved from http://www.bbc.com/future/story/20121022-the-psychology-of-tetris

Tam, P., & Walter, G. (2013). Problematic internet use in childhood and youth: evolution of a 21st century affliction. Australasian Psychiatry, 21(6), 533-6. doi: 10.1177/1039856213509911.

Tolbert, M. A. R. (2004). What is Gestalt organization & systems development? OD Practitioner, 36(4), 6-10.

Touré-Tillery, M., & Fishbach, A. (2011). The course of motivation. Journal of Consumer Psychology, 21(4), 414-423. doi: http://dx.doi.org/10.1016/j.jcps.2011.04.004

Touré-Tillery, M., & Fishbach, A. (2014). How to measure motivation: A guide for the experimental social psychologist. Social and Personality Psychology Compass, 8(7), 328-341. doi: 10.1111/spc3.12110

Wagemans, J., Elder, J. H., Kubovy, M., Palmer, S. E., Peterson, M. A., Singh, M., & von der Heydt, R. (2012). A century of Gestalt psychology in visual perception i. Perceptual grouping and figure-ground organization. Psychological bulletin, 138(6), 1172-1217. doi: 10.1037/a0029333

Webster, D. M., & Kruglanski, A. W. (1994). Individual differences in need for cognitive closure. Journal of personality and social psychology, 67(6), 1049.

Weiner, B. (1992). Human motivation: Metaphors, theories, and research: Newbury Park, CA: Sage Publications, Inc.

Wertheimer, M. (1938). Gestalt Theory. In W. D. Ellis (Ed.), A source book of Gestalt psychology (pp. 1-11). London: Routledge & Kegan Paul Ltd. 

White, R. W. (1959). Motivation reconsidered: the concept of competence. Psychological review, 66(5), 297.

Wicklund, R. A., & Brehm, J. W. (1976). Perspectives on cognitive dissonance. New Jersey: Lawrence Erlbaum Associates.

Zeigarnik, B. (1938). On finished and unfinished tasks. In W. D. Ellis (Ed.), A source book of Gestalt psychology (pp. 300-314). London: Routledge & Kegan Paul Ltd. 

External links[edit]