Researchers develop the first objective tool for assessing the onset of cognitive decline through the measurement of white spots in the brain.
- MRI brain scans may show white spots that scientists believe are linked to cognitive decline.
- Experts have had no objective means of counting and measuring these lesions.
- A new tool has just been published that both counts white spots and cleverly measures their volumes.
White spots and educated guesses<p>The white spots, or "hyperintensities," are brain lesions, fluid-filled holes in the brain believed to have been left behind by the breaking down of blood vessels that had previously provided nourishment to brain cells.</p><p>Prior to the new research, the quantity of white spots was assessed using an imprecise three-point scale indicating an ascending likelihoods of dementia: A minimal number of spots was considered as level 1, a medium number of spots level 2, and a great number of them level 3.</p>
How the new measurements were derived<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDYwMTc1OS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNDQ1ODExNX0.vqhQJSvL99KjOe24TOs4E8R7c6-pprbXYSrGcIqbVps/img.jpg?width=980" id="c64d9" class="rm-shortcode" data-rm-shortcode-id="002d9b8ef47b5a86c3a387ad2cd90629" data-rm-shortcode-name="rebelmouse-image" />
Credit: sfam_photo/Shutterstock<p>The team of researchers from NYU's Langone's <a href="https://med.nyu.edu/departments-institutes/neurology/divisions-centers/center-cognitive-neurology" target="_blank">Center for Cognitive Neurology</a> and <a href="https://med.nyu.edu/departments-institutes/neurology/divisions-centers/center-cognitive-neurology/alzheimers-disease-research-center" target="_blank">Alzheimer's Disease Research Center</a> were led by <a href="https://med.nyu.edu/faculty/jingyun-chen" target="_blank">Jingyun "Josh" Chen</a>. They analyzed 72 MRI scans from a national database of older people taken as part of the <a href="http://adni.loni.usc.edu" target="_blank">Alzheimer's Disease Neuroimaging Initiative</a> (ADNI). The scans were mostly of white people over age 70, and there were a roughly equivalent number of men and women. Some had normal brain function, some were presenting moderate cognitive decline, and some had severe dementia.</p><p>Without knowing each individual's diagnosis, the researchers analyzed the white spots in their scans. While the team counted each scan's lesions, the innovation they introduced was the production of a 3D measurement for each lesion's fluid volume. The measurement was derived by measuring a lesion's distance from opposite sides of the brain.</p><p>Measurements of 0 milliliters (mL) were assessed for areas without white spots, with other white spots coming up as containing 60 mL of fluid. Chen's team predicted that volumes over 100 milliliters could signify severe dementia.</p><p>"Amounts of white matter lesions above the normal range should serve as an early warning sign for patients and physicians," Chen tells <a href="https://nyulangone.org/news/white-matter-lesion-mapping-tool-identifies-early-signs-dementia" target="_blank">NYU Langone Health NewsHub</a>.</p><p>When the team compared the likely diagnoses derived from their calculations against the individuals' medical records, they found that their predictions were correct about 7 out of 10 times.</p><p>The researchers compiled their formulas into a tool that's available to physicians online for free online at <a href="https://github.com/jingyunc/wmhs" target="_blank" rel="noopener noreferrer">GitHub</a>. The researchers plan to further refine and test it using an additional 1,495 brain scans representing a more diverse group of individuals from the ADNI database.</p>
The new tool and its limits<p>Chen notes that white spots alone may not tell the entire story of an individual's cognitive decline or the onset of dementia. Other factors must be considered as well, including memory loss, hypertension, and brain injuries.</p><p>Nonetheless, says senior investigator <a href="https://med.nyu.edu/faculty/yulin-ge" target="_blank">Yulin Ge</a>, "Our new calculator for properly sizing white matter hyperintensities, which we call 'bilateral distancing,' offers radiologists and other clinicians an additional standardized test for assessing these lesions in the brain, well before severe dementia or stroke damage."</p><p>Having an objective means of measuring white hyperintensities will allow physicians not only to get a better handle on the association between white spots and dementia, but also to track the spots alongside changes to a person's tau and beta-amyloid proteins, two chemicals implicated in Alzheimer's disease and dementia.</p>
Experts explain how lie detectors work, what happens in the brain when we tell lies and how accurate polygraph tests are.
- In a 2002 study, 60 percent of people were found to lie at least once during a 10-minute conversation, with most people telling an average of two or three lies. The polygraph, invented in the early 1920s, detects physiological responses to lying (such as elevated heart and respiratory rates as well as spikes in blood pressure.
- Three main areas of the brain are stimulated during deception: the frontal lobe, the limbic system, and the temporal lobe.
- According to the American Polygraph Association, the estimated accuracy of a polygraph can be up to 87 percent.
What happens in your brain when you lie?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU5ODY0Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY2NDU4OTUzMX0.GHs9ZTFWtuC8IGBQTLsM4qd2LFriJZFuAn4whFj-GZ0/img.jpg?width=1245&coordinates=0%2C19%2C0%2C101&height=700" id="c3d06" class="rm-shortcode" data-rm-shortcode-id="4747d0e2eb354c19bc9d0749c2d28f26" data-rm-shortcode-name="rebelmouse-image" alt="concept of lying polygraph test" />
Image by Shidlovski on Shutterstock<p>We all lie. Some might argue it's human nature. In a 2002 study, 60 percent of people were found to lie at least once during a 10-minute conversation, with most people telling an average of two or three lies. Some lies are small, some are bigger, some are done out of kindness, and some done out of malice. But a lie is a lie, and the way that your body reacts when you lie is the same.</p><p><strong>Lying is an inherently stressful activity. </strong></p><p>When you engage in a false narrative (or a lie), your respiratory and heart rate will increase and you may even start to sweat. While people may vary in the ability to tell a lie, most of the time your body will react in this same way. Exceptions to this rule are, for example, psychopaths, who lack empathy and therefore do not exhibit the typical physiological stress responses when telling a lie. </p><p><strong>Brain imaging studies have shown what really happens in the brain when you tell a lie. </strong></p><p>Lying generally involves more effort than telling the truth, and because of this, it involves the prefrontal cortex. <a href="https://www.scientificamerican.com/article/the-art-of-lying/" target="_blank" rel="noopener noreferrer">A 2001 study</a> by late neuroscientist Sean Spence (University of Sheffield in England) explored fMRI images of the brain while lying. Participants answered questions about their daily routine by pressing a yes or no button on a screen. Depending on the color of the writing, they were to answer either truthfully or with a lie. </p><p>The results showed participants needed more time to formulate a dishonest answer than an honest one, and certain parts of the prefrontal cortex were more active when they were lying. </p><p><a href="https://mashable.com/2013/12/20/psychology-of-lying/?europe=true#:~:text=When%20we%20lie%2C%20it%20stimulates,memories%20and%20creating%20mental%20imagery." target="_blank" rel="noopener noreferrer">Further research</a> explains that three main areas of the brain are stimulated during deception - the frontal lobe works to suppress the truth, the limbic system activates due to the anxiety that comes from lying, and the temporal lobe activates in response to retrieving memories and creating mental imagery (fabricating a believable lie). </p><p><strong>Research also suggests lying becomes easier the more you do it. </strong></p><p><a href="https://pubmed.ncbi.nlm.nih.gov/27775721/" target="_blank" rel="noopener noreferrer">In a 2016 study</a>, Duke psychologist Dan Ariely and his colleagues showed how dishonesty can alter your brain, making it easier to tell lies in the future. When people told lies, the scientists noticed a burst of activity in the amygdala, the part of the brain involved in fear, anxiety, and emotional responses. When the scientists had their subject play a game in which they won money by deceiving their partner, they noticed the negative signals from the amygdala begin to decrease. </p><p>"Lying, in fact, desensitized your brain to the fear of getting caught of hurting others, making lying for your own benefit down the road much easier," wrote Jessica Stillman for <a href="https://www.inc.com/jessica-stillman/the-science-of-lying-more-you-do-it-easier-it-gets.html" target="_blank" rel="noopener noreferrer">INC</a>.</p>
How do lie detectors work?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDU5ODY3MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNzg5MDU0OX0._xLKh6Lu15CNNf0eoLNROD6XGuqiT2R8pKxq0TECV2A/img.jpg?width=1245&coordinates=0%2C193%2C0%2C1994&height=700" id="db217" class="rm-shortcode" data-rm-shortcode-id="092c4388f3cea4afb66387c522754519" data-rm-shortcode-name="rebelmouse-image" alt="lie detector illustration" />
The polygraph will be able to detect if someone is telling the truth 87 percent of the time.
Image by OllivsArt on Shutterstock<p>In 1921, a California-based police officer and physiologist John A. Larson created an apparatus that simultaneously measures continuous changes in blood pressure, heart rate, and respiration rate to aid in the detection of deception. This was the invention of the polygraph, which is commonly referred to as a lie detector.</p><p>Seven years before this, in 1914, an Italian psychologist (Vittorio Benussi) published findings on "the respiratory symptoms of a lie," and in 1915, an American psychologist and lawyer (William M. Marston) invented a blood pressure test for the detection of deception.</p><p>The accuracy of polygraph tests has been called into question for nearly as long as they've existed. These machines detect typical stress responses to telling a lie. This means increased heart rate, blood pressure, and respiration rate. Some people are naturally good liars, or become better with controlling these stress responses, and can manage to stay calm during a lie detector test. </p><p><a href="https://www.psychologytoday.com/us/blog/the-nature-deception/202001/do-lie-detector-tests-really-work#:~:text=It%20does%20work%20much%20of,trained%20polygraph%20examiner%20can%20tell.&text=They%20estimate%20the%20accuracy%20of,lying%20or%20telling%20the%20truth" target="_blank" rel="noopener noreferrer">According to the American Polygraph Association</a> (made up largely of polygraph examiners), the estimated accuracy of a polygraph can be up to 87 percent. That means that in 87 out of 100 cases, the polygraph will be able to detect if someone is telling the truth.</p><p>If the person lies but doesn't have the stress symptoms of telling that lie, they will pass the test. Similarly, innocent people may fail the test due to being anxious about taking it to begin with and therefore emitting the elevated heart, respiratory, and blood pressure rates that can be detected. </p>
In some situations, asking "what if everyone did that?" is a common strategy for judging whether an action is right or wrong.
Researchers explore the "complex web of connections" in your brain that allows you to make split second decisions.
- Researchers at the University of Colorado discovered the cerebellum's role in split-second decision making.
- While it was previously thought that the cerebellum was in charge of these decisions, it's been uncovered that it is more like a "complex web of connections" through the brain that goes into how you make choices.
- If the decision is made within 100 milliseconds (of being presented with the choice), the change of mind will succeed in altering the original course of action.
Photo: StunningArt / Shutterstock<p>This understanding of the cerebellum's role in decision-making is new. Because the mice became less confident in their choices after the release of those agents, it appears the cerebellum is partly responsible for quick decision-making responses.</p><p>Restrepo notes that the cerebellum is responsible for a lot of learning—perhaps unsurprisingly, given its proximity to the spinal cord and its influence on motor patterns. Split-second decisions are an old evolutionary necessity and would have started evolving quite early on. As he <a href="https://news.cuanschutz.edu/news-stories/cu-anschutz-researchers-shed-light-on-split-second-decision-making" target="_blank">says</a>,</p><p>"We found an entire subset of brain cells that change after learning. It sheds further light on how the cerebellum functions and the complex web of connections that go into quick decision making."</p><p><strong>How long does it take to make a split decision and have good results?</strong></p><p>The researchers in Susan Courtney's study highlighted that timing is everything when it comes to these quick decisions. If the decision to change is made within 100 milliseconds (of being presented with the choice), the change of mind will succeed in altering the original course of action. However, if it takes at least (or more than) 200 milliseconds, the chances of the change succeeding are significantly less.</p>
Psychologists W. Keith Campbell, (Ph.D.) and Carolyn Crist explain why narcissists rise to power and how to make sure your support is going to someone making effective, positive change.
- Pathological narcissism is rare. It impacts an estimated 1 percent of the population.
- Narcissism is tied closely to leadership emergence, as narcissists tend to initially be confident, charismatic, and charming. Leadership is a natural goal for narcissists because it feeds their motivational goals of status, power, and attention.
- Psychologists W. Keith Campbell, (Ph.D.) and Carolyn Crist explain why narcissists rise to power.