Tag Archives: psychology


Some dreams may help our brains process our thoughts and the events of the day. Others may just be the result of normal brain activity and mean very little, if anything. Researchers are still trying to figure out exactly why we dream.


Behavioral economics

Behavioral economics, along with the related sub-field behavioral finance, studies the effects of psychological, social, cognitive, and emotional factors on the economicdecisions of individuals and institutions and the consequences for market prices, returns, and resource allocation, although not always that narrowly, but also more generally, of the impact of different kinds of behavior, in different environments of varying experimental values.[1] Behavioral economics is primarily concerned with the bounds of rationality ofeconomic agents. Behavioral models typically integrate insights from psychology, neuroscience and microeconomic theory; in so doing, these behavioral models cover a range of concepts, methods, and fields.[2][3]

The study of behavioral economics includes how market decisions are made and the mechanisms that drive public choice. The use of the term “behavioral economics” in U.S. scholarly papers has increased in the past few years, as shown by a recent study.[4]

There are three prevalent themes in behavioral finances:[5]

Overgeneral autobiographical memory (OGM)

Overgeneral autobiographical memory (OGM) is an inability to retrieve specific memories from one’s autobiographical memory.[1] Instead, general memories are recalled, such as repeated events or events occurring over broad periods. For example, when asked to recall a happy event, a person who exhibits OGM may say, “when I was on vacation last month” instead of remembering a single incident, such as, “my high school graduation.”[2] Research shows a correlation between OGM and certain mental illnesses, such as major depressive disorder (MDD) and posttraumatic stress disorder (PTSD).[3]

Stroop effect

In psychology, the Stroop effect is a demonstration of interference in thereaction time of a task. When the name of a color (e.g., “blue”, “green”, or “red”) is printed in a color not denoted by the name (e.g., the word “red” printed in blue ink instead of red ink), naming the color of the word takes longer and is more prone to errors than when the color of the ink matches the name of the color. The effect is named after John Ridley Stroop, who first published the effect in English in 1935.[1] The effect had previously been published in Germany in 1929.[2][3][4]The original paper has been one of the most cited papers in the history ofexperimental psychology, leading to more than 701 replications.[4] The effect has been used to create a psychological test (Stroop test) that is widely used in clinical practice and investigation.

Brain imaging techniques including magnetic resonance imaging (MRI), functional magnetic resonance imaging (fMRI), and positron emission tomography (PET) have shown that there are two main areas in the brain that are involved in the processing of the Stroop task.[7] They are the anterior cingulate cortex, and the dorsolateral prefrontal cortex.[8]More specifically, while both are activated when resolving conflicts and catching errors, the dorsolateral prefrontal cortex assists in memory and other executive functions, while the anterior cingulate cortex is used to select an appropriate response and allocate attentional resources.[9]

The posterior dorsolateral prefrontal cortex creates the appropriate rules for the brain to accomplish the current goal.[9] For the Stroop effect, this involves activating the areas of the brain involved in color perception, but not those involved in word encoding.[10] It counteracts biases and irrelevant information, for instance, the fact that the semantic perception of the word is more striking than the color in which it is printed. Next, the mid-dorsolateral prefrontal cortex selects the representation that will fulfil the goal. The relevant information must be separated from irrelevant information in the task; thus, the focus is placed on the ink color and not the word.[9] Furthermore, research has suggested that left dorsolateral prefrontal cortex activation during a Stroop task is related to an individual’s’ expectation regarding the conflicting nature of the upcoming trial, and not so much on the conflict itself. Conversely, the right dorsolateral prefrontal cortex aims to reduce the attentional conflict and is activated after the conflict is over.[8]

Moreoever, the posterior dorsal anterior cingulate cortex is responsible for what decision is made (i.e. whether you will say the incorrect answer [written word] or the correct answer [ink color]).[8] Following the response, the anterior dorsal anterior cingulate cortex is involved in response evaluation—deciding whether the answer is correct or incorrect. Activity in this region increases when the probability of an error is higher.[11]

In the neo-Piagetian theories of cognitive development, several variations of the Stroop task have been used to study the relations between speed of processing and executive functions with working memory and cognitive development in various domains. This research shows that reaction time to Stroop tasks decreases systematically from early childhood through early adulthood. These changes suggest that speed of processing increases with age and that cognitive control becomes increasingly efficient. Moreover, this research strongly suggests that changes in these processes with age are very closely associated with development in working memory and various aspects of thought.[21][22]

survivor bias

Lucky people generate their own good fortune via four basic principles.

  • They are skilled at creating and noticing chance opportunities,
  • make lucky decisions by listening to their intuition,
  • create self-fulfilling prohesies via positive expectations, and
  • adopt a resilient attitude that transforms bad luck into good.


This project scientifically explores why some people live such charmed lives, and develops techniques that enable others to enhance their own good fortune. The research has involved working with hundreds of exceptionally lucky and unlucky people, and the findings have been published in The Luck Factor. For an overview of this work, download this articlefrom Skeptical Inquirer magazine.
The Four Principles

Prof Wiseman has identified the four basic principles that lucky people use to create good fortune in their lives.

Principle One: Maximise Chance Opportunities
Lucky people are skilled at creating, noticing and acting upon chance opportunities. They do this in various ways, including networking, adopting a relaxed attitude to life and by being open to new experiences.

Principle Two: Listening to Lucky Hunches
Lucky people make effective decisions by listening to their intuition and gut feelings. In addition, they take steps to actively boost their intuitive abilities by, for example, meditating and clearing their mind of other thoughts.

Principle Three: Expect Good Fortune
Lucky people are certain that the future is going to be full of good fortune. These expectations become self-fulfilling prophecies by helping lucky people persist in the face of failure, and shape their interactions with others in a positive way.

Principle Four: Turn Bad Luck to Good
Lucky people employ various psychological techniques to cope with, and often even thrive upon, the ill fortune that comes their way. For example, they spontaneously imagine how things could have been worse, do not dwell on ill fortune, and take control of the situation.

Luck School

Prof Wiseman’s work also involves developing techniques that help people think and behave like a lucky person. The efficacy of these techniques has been scientifically tested in a series of experiments referred to as ‘luck school’. The project has proved highly successful, with almost all participants reporting significant life changes, including increased levels of luck, self-esteem, confidence and success.


BBC Online article on Prof Wiseman’s luck research

Forbes.com carries Prof. Wiseman’s article on the psychology of opportunity.

Fast Company article on The Luck Factor in business.

The Times reports Prof Wiseman’s work on creating opportunities and his book, Did You Spot the Gorilla?

The Daily Telegraph reports on an experiment on connectivity and luck.

Report on Prof Wiseman’s work exploring luck and superstition.

How the Survivor Bias Distorts Reality

learning only from success is a deeper problem than you imagine

Survivorship bias, or survival bias, is the logical error of concentrating on the people or things that “survived” some process and inadvertently overlooking those that did not because of their lack of visibility. This can lead to false conclusions in several different ways. The survivors may be actual people, as in a medical study, or could be companies or research subjects or applicants for a job, or anything that must make it past some selection process to be considered further.

Survivorship bias can lead to overly optimistic beliefs because failures are ignored, such as when companies that no longer exist are excluded from analyses of financial performance. It can also lead to the false belief that the successes in a group have some special property, rather than just coincidence. For example, if three of the five students with the best college grades went to the same high school, that can lead one to believe that the high school must offer an excellent education. This could be true, but the question cannot be answered without looking at the grades of all the other students from that high school, not just the ones who “survived” the top-five selection process.

Survivorship bias is a type of selection bias.

In Search of Excellence is an international bestselling book written by Tom Peters and Robert H. Waterman, Jr..

First published in 1982, it is one of the biggest selling business books ever, selling 3 million copies in its first four years, and being the most widely held monograph in the United States from 1989 to 2006 (WorldCat data).

The book purports to explore the art and science of management used by several 1980s companies.

As early as 1984 it was apparent, to certain analysts, that the book’s choice of companies was poor to indifferent. NCR, Wang Labs, Xerox and others did not produce excellent results in their balance sheets in the 1980s.

Rick Chapman titled his book on high-tech marketing fiascoes, In Search of Stupidity, as a nod to Peters’s book and the disasters that befell many of the companies it profiled. He notes that “with only a few exceptions… [the excellent companies were] large firms with dominant positions in markets that were senescent or static.”

In an article in Fast Company, cited below, Peters remarked that the criticism that “If these companies are so excellent, Peters, then why are they doing so badly now,” in his opinion “pretty much misses the point.”[6]

The research methodology employed by the authors of this book is also severely criticized by Phil Rosenzweigh in his book “The Halo Effect” [7] as the “Delusion of Connecting the Winning Dots”. Rosenzweigh opines that it was not possible to identify the traits that make a company perform simply by studying already-performing companies which Peters and Waterman did.

Peters’ “confession” of “faked data”

In December, 2001, Fast Company printed an article, crediting Tom Peters as author, entitled “Tom Peters’s True Confessions”. Most of the “confessions” were humorously self-deprecating remarks (In Search of Excellence had been “an afterthought… a hip-pocket project that was never supposed to amount to much”). One of them, however, used the term “faked data:”

This is pretty small beer, but for what it’s worth, okay, I confess: We faked the data. A lot of people suggested it at the time. The big question was, How did you end up viewing these companies as “excellent” companies? A little while later, when a bunch of the “excellent” companies started to have some down years, that also became a huge accusation: If these companies are so excellent, Peters, then why are they doing so badly now? Which I’d say pretty much misses the point.
[In] Search [of Excellence] started out as a study of 62 companies. How did we come up with them? We went around to McKinsey’s partners and to a bunch of other smart people who were deeply involved and seriously engaged in the world of business and asked, Who’s cool? Who’s doing cool work? Where is there great stuff going on? And which companies genuinely get it? That very direct approach generated a list of 62 companies, which led to interviews with the people at those companies. Then, because McKinsey is McKinsey, we felt that we had to come up with some quantitative measures of performance. Those measures dropped the list from 62 to 43 companies. General Electric, for example, was on the list of 62 companies but didn’t make the cut to 43 — which shows you how “stupid” raw insight is and how “smart” tough-minded metrics can be.
Were there companies that, in retrospect, didn’t belong on the list of 43? I only have one word to say: Atari.
Was our process fundamentally sound? Absolutely! If you want to go find smart people who are doing cool stuff from which you can learn the most useful, cutting-edge principles, then do what we did with Search: Start by using common sense, by trusting your instincts, and by soliciting the views of “strange” (that is, nonconventional) people. You can always worry about proving the facts later.[6]

BusinessWeek ran an article about Fast Company’s article. As related by BusinessWeek, the article was actually written by Fast Company founding editor Alan M. Webber, based on a six-hour interview with Peters. Peters reviewed and approved the article prior to publication, but the actual phrase “we faked the data” was Webber’s, and Peters had not actually used these words during the interview. BusinessWeek quoted Peters as saying “Get off my case. We didn’t fake the data.” According to BusinessWeek, Peters says he was “pissed” when he first saw the cover. “It was his [Webber’s] damn word,” he says. “I’m not going to take the heat for it.”[8]

The definition of luck (or chance) varies by the philosophical, religious, mystical, and emotional context of the one interpreting it; according to the classic Noah Webster‘s dictionary, luck is “a purposeless, unpredictable and uncontrollable force that shapes events favourably or unfavourably for an individual, group or cause”.[1] Yet the author Max Gunther defines it as “events that influence one’s life and are seeminglybeyond one’s control”.[2]

When thought of as a factor beyond one’s control, without regard to one’s will, intention, or desired result, there are at least two senses that people usually mean when they use the term, the prescriptive sense and the descriptive sense. In the prescriptive sense, luck is asupernatural and deterministic concept that there are forces (e.g. gods or spirits) that prescribe that certain events occur very much the way laws of physics will prescribe that certain events occur. It is the prescriptive sense that people mean when they say they “do not believe in luck“. In the descriptive sense, people speak of luck after events that they find to be fortunate or unfortunate, and maybe improbable.

Therefore, cultural views of luck vary from perceiving luck as a matter of random chance to attributing to such explanations of faith orsuperstition. For example, the Romans believed in the embodiment of luck as the goddess Fortuna,[3] whereas the philosopher Daniel Dennett believes that “luck is mere luck” rather than a property of a person or thing.[4] Carl Jung viewed luck as synchronicity, which he described as “a meaningful coincidence”.

Lucky symbols are popular worldwide and take many forms.

Ego depletion

Ego depletion refers to the idea that self-control or willpower draw upon a limited pool of mental resources that can be used up.[1] When the energy for mental activity is low, self-control is typically impaired, which would be considered a state of ego depletion. In particular, experiencing a state of ego depletion impairs the ability to control oneself later on. A depleting task requiring self-control can have a hindering effect on a subsequent self-control task, even if the tasks are seemingly unrelated. Self-control plays a valuable role in the functioning of the self on both individualistic and interpersonal levels. Ego depletion is therefore a critical topic in experimental psychology, specifically social psychology, because it is a mechanism that contributes to the understanding of the processes of human self-control.

The word “ego” in “ego depletion” is used in the psychological sense rather than the colloquial sense.

American social psychologist Roy Baumeister and his colleagues proposed a model that relates self-control to a muscle, which can become both strengthened and fatigued. Initial use of the “muscle” of self-control will cause a decrease in strength, or ego depletion, for subsequent tasks. Multiple experimental findings show support for this muscle model of self-control and ego depletion.[2]

A key experiment by Roy Baumeister, Ellen Bratslavsky, Mark Muraven and Dianne Tice in 1998, demonstrated some of the first evidence that ego depletion has effects in many diverse contexts or situations.[1] They showed that people who initially resisted the temptation of chocolates were subsequently less able to persist on a difficult and frustrating puzzle task. They attributed this effect to ego depletion, which resulted from the prior resisting of a tempting treat. Additionally, it was demonstrated that when people voluntarily gave a speech that included beliefs contrary to their own, they were also less able to persist on the difficult puzzle, indicating a state of ego depletion. Interestingly, this effect was not nearly as strong when individuals were not given a choice and were “forced” to write a counter-attitudinal speech. Thus, it is believed that both the act of choice and counter-attitudinal behaviors draw upon the same pool of limited resources. While giving a counter-attitudinal speech is expected to produce ego depletion, introducing the element of choice further increases the level of experienced depletion. These findings demonstrated the effects of ego depletion in differential situations and emphasized that ego depletion is not context-specific. This experiment was critical in that the researchers synthesized ideas proposed by prior studies that had suggested evidence for a strength model of willpower. With this study, Baumeister and his colleagues therefore provided the first direct experimental evidence of ego depletion, and initiated research interest on the subject.

Physiological correlates

The role of glucose as a specific form of energy needed for self-control has been explored. Glucose, a sugar found in many foods, is a vital fuel for the body and the brain. Multiple experiments have connected self-control depletion to reduced blood glucose, and that self-control performance could be replenished by consuming glucose (e.g., lemonade).[3] However, some (but not all) of the findings were questioned.[4] Several recent experiments have found that resource depletion effects can be reversed by simply tasting (but not swallowing or consuming) sweet beverages,[5][6][7] which can have rewarding properties.[8] Others have suggested that the taste of sugar (but not artificial sweetener) has psycho-physiological signaling effects.

An experiment by Segertrom (2007) and Solberg Nes, has shown that HRV (heart rate variability) is a marker for both ego depletion, and an index for self-control power before the task. [1]

The underlying neural processes associated with self-control failure have been recently examined using neurophysiological techniques. According to cognitive and neuroscientific models of mental control, a “conflict-monitoring/error-detection system” identifies discrepancies between intended goals and actual behaviors.[9] Error-related negativity (ERN) signals are a waveform of event-related potentials, which appear to be generated in the anterior cingulate cortex when individuals commit errors in various psychological tasks.[10]Using electroencephalography (EEG) recordings, Inzlicht and Gutsell found that individuals who had undergone an emotion-suppression task displayed weaker ERN signals compared to individuals who had not undergone emotion-suppression tasks.[9] These findings demonstrate preliminary evidence that depletion experienced after exerting self-control, can weaken neural mechanisms responsible for conflict monitoring.
The majority of ego depletion studies have been carried out on university students, which raises concerns about how generalizable the results really are. The effects of age are unknown, but maybe younger people are more susceptible to the effects of ego depletion, given that the areas of the brain involved in self-control continue to develop until the mid 20s. For example, a recent study found that people over the age of 40 did not become ego depleted following a typical depletion manipulation, whereas younger university students did.[11]

Although self-control has traditionally been thought of as a limited resource that can be depleted, some researchers disagree with this model[2]. While multiple studies provide support for the ego depletion effect, there is currently no direct measure of ego depletion, and studies mainly observe it by measuring how long people persist at a second task after performing a self-control task (the depleting task).[1] The theory of ego depletion relies on the inner workings of an individual’s volition, which can only be indirectly tested; therefore, only inferences can be made. Another challenge facing research on ego depletion is the influence of the overall mental conditions of individuals being studied. There is speculation that results may be disrupted in individuals who report experiencing depression and already possess high levels of ego depletion prior to the study.

Many ego depletion studies, however, have shown that mood is not relevant to the results. In fact, many of the earlier experiments have tested for the effects of mood and saw no effect of mood whatsoever. Furthermore, the study and measurement of ego depletion may be affected by the confounding effect of cognitive dissonance. Researchers have questioned whether subjects are truly experiencing ego depletion, or whether the individuals are merely experiencing cognitive dissonance in the psychological tasks.[1]

Process model

In contrast to the original most known model of self-control, Michael Inzlicht and Brandon J. Schmeichel propose an alternative model of depletion, which they refer to as the process model.[26] This process model holds that initial exertions of willpower lead an individual’s motivation to shift away from control, and towards gratification. As a part of this process, one’s attention shifts away from cues that signal the need for control, and towards cues that signal indulgence. Inzlicht and Schmeichel argue that the process model provides a starting point for understanding self-control and that more research examining these cognitive, motivational, and affective influences on self-control is needed.

Reproducibility controversy and conflicting meta analyses

A 2010 meta analysis found the effect significant. Even after accounting for possible unpublished failed studies, the analysis concluded that it is extremely unlikely that the effect is untrue. [27] In 2015, another meta analysis argued that more strict meta analysis and different statistical models show no effect. [28][29] Others, however questioned the statistical analysis used in this analysis.[30]

In 2016, a major study carried out at two dozen labs across the world using a single protocol failed to find any evidence for ego depletion.[31][32]

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