Catherine Leona, BA – Brain Blogger http://brainblogger.com Health and Science Blog Covering Brain Topics Wed, 30 May 2018 15:00:03 +0000 en-US hourly 1 https://wordpress.org/?v=4.9.6 Improve Your Gambling Odds – Do Not Think Like a Winner http://brainblogger.com/2014/03/13/improve-your-gambling-odds-do-not-think-like-a-winner/ http://brainblogger.com/2014/03/13/improve-your-gambling-odds-do-not-think-like-a-winner/#comments Thu, 13 Mar 2014 14:36:22 +0000 http://brainblogger.com/?p=16148 My Aunt C. took up an unlikely hobby after her retirement as a school teacher. Not long after she read her last Dr. Seuss to a roomful of children, a flashing neon sign on the highway lured her to the new casino. From then on, whenever my parents visited Aunt C., I no longer heard about golf scores but of small wins at the slot machines at the casino.

The Curse of the “Almost Winners”

Despite Aunt C’s loyal business, the blackjack tables were not always happy to see the thrice-weekly visitor with the sharp sixth sense. The casino was more interested in her revolving coterie of friends, especially the near-missers. Near-missers are gamblers who breakeven or come close to winning at the slot machines, roulette tables, poker games and other games of chance. As long as they are not incurring major losses, these ‘almost winners’ keep returning expecting their luck to turn in their favor. Previously, scientists have attributed this intoxicating behavior to the dopamine effect — the feel-good hormone that reinforces behavior.

Scientists now have the brain images to show what they suspected all along about near-missers — these losers think they are winners. More specifically, a near win triggers the same reward circuitry as a win. Both winners and near-missers have more theta-band activity in the insula and right orbitofrontal cortex (OFC) of the brain. This near-miss effect is what makes pathological gamblers return to the blackjack table even though they are not winning.

Gambling While High on Theta

Theta waves (4–7 Hertz or cycles per second) are associated with zoning out. If you just missed five minutes of your business meeting, you were likely in the theta zone daydreaming. Theta oscillations in the prefrontal cortex create a number of other faulty circuitry that may predispose us to take more risks. When theta brainwave activity is high, humans are more apt to circumvent the human instinct to act in a way that gains rewards and avoids punishment to achieve a goal. The rational man may choose to walk away from the casino’s offer of free chips to stay in a high stakes blackjack game. The irrational man may take the offer even though he has six month’s salary at risk, beating his built-in instinctual bias to avoid the high potential losses.

Gamblers high on theta from a winner’s mentality are less likely to cooperate and more likely to increase the potential losses of all players. In an ultimatum game, players with prefrontal theta oscillations were less likely to adapt their behavior to cooperate with an adversary and maximize earnings in a game. In a strategic game such as Mahong that requires cooperation, a selfish winner’s mentality can be a form of self-sabotage. In blackjack, a player on a theta high may forego a gentlemanly wager and raise the stakes far beyond the comfort level of all players.

Are the Odds Stacked Against You?

Manufacturers of gambling machines well aware of the near-miss effect have been accused of designing gambling machines and games of chance to create more near misses than chance. Over time, a higher number of near misses in gambling machines has been shown to lower performance. The suspected rigging of gambling machines for near misses is at the center of several lawsuits. Calling on the latest research, pathological gamblers can now present evidence, in the form of brain images, of how manipulating the number of near misses feeds their gambling addiction.

The gambling industry is exploiting our predisposition to breakeven in games of chance. When we spend an entire evening at the slot machines our schooling tells us that, at the very least, we will breakeven — according to the theory of probability, a basis of all fields from science to psychology since 17th century Frenchmen developed it while debating the outcomes of a roll of dice. The laws of probability dictate that if a coin is repeatedly tossed, over time, it will come up heads 50% of the time and tails 50% of the time.  Even if the gambler has experienced losses, he will still find betting opportunities that provide the prospect to breakeven attractive, according to Richard Thaler, the founding father of behavioral economics.

Despite what the positive psychologists say, in gambling, thinking like a winner when you are not winning is likely to lead to losing more money.

References

Billeke P, Zamorano F, López T, Rodriguez C, Cosmelli D, & Aboitiz F (2014). Someone has to Give In: Theta Oscillations Correlate with Adaptive Behavior in Social Bargaining. Social cognitive and affective neuroscience PMID: 24493841

Dymond S, Lawrence NS, Dunkley BT, Yuen KS, Hinton EC, Dixon MR, Cox WM, Hoon AE, Munnelly A, Muthukumaraswamy SD, & Singh KD (2014). Almost winning: Induced MEG theta power in insula and orbitofrontal cortex increases during gambling near-misses and is associated with BOLD signal and gambling severity. NeuroImage, 91C, 210-219 PMID: 24457067

Oberg, S., Tata, M. S., & Gruber, A. J. (2013, January). The Value of Uncertainty: A Reinforcement Learning Model of Increased Risk Seeking During Gambling With Near-Miss Outcomes. In JOURNAL OF COGNITIVE NEUROSCIENCE (pp. 178-178). 55 HAYWARD STREET, CAMBRIDGE, MA 02142 USA: MIT PRESS.

Thaler, R., & Johnson, E. (1990). Gambling with the House Money and Trying to Break Even: The Effects of Prior Outcomes on Risky Choice Management Science, 36 (6), 643-660 DOI: 10.1287/mnsc.36.6.643

Image via Fer Gregory / Shutterstock.

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False Memories on Trial – Embed, Manipulate, Delete http://brainblogger.com/2014/02/09/false-memories-on-trial-embed-manipulate-delete/ http://brainblogger.com/2014/02/09/false-memories-on-trial-embed-manipulate-delete/#comments Sun, 09 Feb 2014 12:00:23 +0000 http://brainblogger.com/?p=15902 Recent successful efforts by neuroscientists to falsify, change, delete, and improve memories highlight how highly manipulable memories are. This growing awareness is behind the call by memory experts for a protocol to regulate memory manipulation of witnesses by therapists, lawyers, and law enforcement officials.

A popular topic in neuroscience, recent research on memory manipulation is showing how easy it is to tamper with recovered memories. Even brief confirmatory feedback by a law enforcement officer to an eyewitness such as “good job, your description matches a suspect” can change a jury verdict. By increasing the confidence of the witness, confirmatory feedback creates over-belief in what he or she is reporting.

When confirmatory feedback was provided to witnesses in a recent study, those listening to the testimony judged the testimony of accurate and mistaken eyewitness accounts at the same level of credibility. Without the feedback, jurors are two times more likely to believe the true versus the false testimony.

A closer look into recent advances in the neuroscience of memory reactivation may shed light on why interference such as confirmatory feedback creates false testimonies that eyewitnesses often retract at a later date. When study participants were asked to perform repetitive tasks, scientists at the National Institute of Neurological Disorders and Stroke demonstrated that interference with memory reactivation can decrease functional connectivity between the cerebellum and cerebral cortex — two brain areas that communicate through polysnynaptic circuits. An example of such interference is the pressuring of a witness by police to wrongly identify Larry Henderson in a photo as a suspect in a New Year’s day shooting in New Jersey.

In the study, when subjects began to perform the memorized tasks again, the cerebellar-cortical connectivity appeared to be reset. In the case of Henderson, who was later exonerated by DNA, the defense asking the witness over and over if he was too high on cocaine to identify the shooter could be a example of memory reset mechanism. The demonstration of the ambiguity of memory by these studies helps explain the conclusions of a report by the Innocence Project that 75% of the 270 people exonerated by DNA in the United States were wrongfully convicted by mistaken eyewitness testimony.

Regional brain connectivity deficits have also been shown to affect working memory in schizophrenics and psychopaths. These memory deficits may explain why psychopaths are more likely to lie in court. While studies have shown that we have memory bias towards emotional versus neutral events and their contexts, psychopaths’ memories are disassociated from the context, which would lead to less accurate memories.

Following a 2012 ruling of the New Jersey Supreme Court involving the Henderson case, more jurors are being educated on the scientific evidence for how memory works. We are learning that memory is more like real-time streaming than a video recording, and is continuously edited by our perceptions, imagination, experiences and a myriad of other interfering factors. Naturally, jurors are beginning to question the authenticity of memories.

Neuroscientists are getting closer to the day when, as expert witnesses, they will be able to independently and definitively identify if a memory is authentic. Acting as neural detective to identify if a memory has indeed existed, brain imaging can compare subjective versus objective memories and whether they are new or old memories. The idea is to track brain patterns to determine if a memory is mnemonically perceived as having been previously experienced. Indeed, a groundbreaking 2010 study by Stanford neuroscientists showed that brain imaging can be used to determine whether a witness’ recognition of a face is old or new.

Of equal concern to court cases is the manipulation of memories post-trauma, especially during therapy. Carol Felstead, for example, received “thought stopping” treatment to dampen her memories of satanic abuse. Scientists have employed numerous techniques to manipulate memories. Those involving the hippocampus, where memory traces may be replayed and reinforced or blocked and impaired, include brain stimulation to alter memories, the reactivation of memories through cues during sleep, and medication. These same techniques have also been used to treat post-traumatic stress disorder and depression after traumatic events.

Longer term, neuroscience is striving to retrieve perfectly intact memories. Mental time travel, a fascinating area formerly in the realm of science fiction, offers the greatest potential among the latest developments in memory research. When neuroscience can retrieve a memory intact in the context in which it was recorded, the credibility of eyewitness testimony will be restored.

Some of this new research is expected to surface in false memory cases slated for 2014 as neuroscience-based evidence takes center stage in trials involving eyewitness testimony. Current advances in brain imaging allowing us to ascertain the veracity of recovered memories (whether they are new or old) could soon vindicate many victims and falsely accused, as well as illuminate and regulate the practices of mental health and law enforcement officials.

Until then, the growing awareness of how easily our memories can be manipulated by ourselves and others is hastening the need for the strengthening of eyewitness questioning protocols to prevent distortion and ensure the contextual preservation of memories.

References

Censor N, Horovitz SG, & Cohen LG (2014). Interference with existing memories alters offline intrinsic functional brain connectivity. Neuron, 81 (1), 69-76 PMID: 24411732

Felstead, K. and Felstead, R. (2013). Justice for Carol – The True Story of Carol Felstead. Britain.

The Innocence Project. Reevaluating Lineups: Why Witnesses Make Mistakes and How to Reduce the Chance of a Misidentification.

Glass SJ, & Newman JP (2009). Emotion processing in the criminal psychopath: the role of attention in emotion-facilitated memory. Journal of abnormal psychology, 118 (1), 229-34 PMID: 19222329

Meyer-Lindenberg A, Poline JB, Kohn PD, Holt JL, Egan MF, Weinberger DR, & Berman KF (2001). Evidence for abnormal cortical functional connectivity during working memory in schizophrenia. The American journal of psychiatry, 158 (11), 1809-17 PMID: 11691686

Rissman J, Greely HT, & Wagner AD (2010). Detecting individual memories through the neural decoding of memory states and past experience. Proceedings of the National Academy of Sciences of the United States of America, 107 (21), 9849-54 PMID: 20457911

Schacter DL, & Loftus EF (2013). Memory and law: what can cognitive neuroscience contribute? Nature neuroscience, 16 (2), 119-23 PMID: 23354384

Smalarz L, & Wells GL (2013). Post-Identification Feedback to Eyewitnesses Impairs Evaluators’ Abilities to Discriminate Between Accurate and Mistaken Testimony. Law and human behavior PMID: 24341835

Image via bikriderlondon / Shutterstock.

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