, ,

Cracking cases with nuclear forensics

Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy; photographer Jason Richards

Oak Ridge National Laboratory’s Joe Giaquinto investigates chemical clues for
trace-level radioactivity. Giaquinto leads ORNL’s Nuclear Analytical Chemistry
and Isotopics Laboratory, which makes critical contributions to nuclear forensics
and nonproliferation.

Specialized team uses nuclear forensics
to solve mysteries and safeguard materials

A group of nuclear detectives at the Department of Energy's Oak Ridge National Laboratory takes on tough challenges, from detecting illicit uranium using isotopic "fingerprints" to investigating Presidential assassination conspiracies.

"A very big capability at Oak Ridge exists for nuclear analytics, all the way from helping commercial production of nuclear power to making sure the world's nuclear materials are properly accounted for," said ORNL's Joseph Giaquinto, leader of the Nuclear Analytical Chemistry and Isotopics Laboratories, or NACIL. "My group is a specialized analytical group. We focus in the nuclear arena, from nuclear fuels R&D to nuclear forensics and safeguarding nonproliferation."

From the Manhattan Project in the 1940s to the High Flux Isotope Reactor's 50th anniversary and its selection as an American Nuclear Society Nuclear Historic Landmark, ORNL has been the preeminent destination for nuclear R&D.

Now NACIL researchers are bringing attention once again to ORNL's nuclear capabilities. Equipped with the world's best elemental mass spectrometers, superb cleanrooms and unmatched experience, the ORNL scientists are in high demand.

For instance, within the NACIL group are the analytical laboratories which were the first to be approved for as a network analytical laboratory for the United Nation's International Atomic Energy Agency (IAEA), assisting the "Atoms for Peace" organization's goal of safeguarding nuclear nonproliferation with global tests to detect illicit uranium enrichment activity.

In 2011 ORNL invested in its nuclear analytical chemistry group, converting the Mouse House, an underused facility that once held the national lab's groundbreaking genetics program, into the state-of-the-art Ultra-Trace Forensics Science Facility. Over the last two years the U.S. Department of State provided NACIL investments totaling more than $1.5 million to replace aging mass spectrometers with state-of-the-art instruments with capabilities unmatched in sensitivity and precision. Under Giaquinto's six-year leadership, the group's funding for nuclear forensics work has skyrocketed, increasing nearly 10-fold over previous years.

With growing project requests coming from myriad sources like the State Department, the U.S. Department of Homeland Security, NASA and IAEA, the ORNL scientists are applying seventy-plus years of nuclear know-how to tackle some of the world's most pressing nuclear security problems.

Sleuthing for success NACIL scientists have examined numerous nuclear "crime scenes." They unraveled the mysteries behind President John F. Kennedy's assassination and President Zachary Taylor's sudden death using mere hair strands, fingernail shards and bullet fragments. They analyzed ratios of elements in mixed-oxide fuel for the U.S. Nuclear Regulatory Commission, profiling the alternative fuel source's safety and effectiveness. And they reached even higher, helping in the development of a production process to create the source materials for NASA's deep-space battery for the next era of interplanetary exploration.

NACIL's twenty-plus researchers collaborate from several sites throughout the national laboratory's campus. The team's ingenuity and experience are invoked on a variety of global projects, such as teaching analytical practices at international Centers of Excellence for safeguards and, in the case of NACIL's Rob Smith, co-patenting a chemical detector that can "sniff out" secret graves.

The team often works with radioactive materials, assisting in development of methods for extracting high-purity isotopes for medical use and performing detailed chemical extractions and isolations. Measurements like these enable improved simulations for irradiation of the material, providing a radiochemical template for better understanding nuclear materials.

Examinations to find remnants of trace-level radioactive material are a cornerstone of NACIL efforts. A large portion of the group's trace-level forensic work began as a pilot project two years ago -- and was so successful that the program is now an ORNL mainstay. The development of rapid techniques for separating elements and their isotopes and methods for detecting trace "fingerprints" in nuclear materials now benefit their multiple national sponsors in the arena of nuclear forensics.

To assure smear kits are not contaminated prior to sample collection, chemists screen them in HFIR's irradiation facilities before the kits are deployed in the field. The IAEA, the world's nuclear watchdog, can then use the approved kits to swipe nuclear facilities to detect if a nation has broken promises to abate enrichment and violated nonproliferation agreements.

But it is neutron activation analysis, or NAA, that gives this team its unique capabilities. Access to the world's highest continuous thermal neutron flux enables the lowest detection limits for uranium and plutonium of any global NAA facility. ORNL scientists use it to characterize nuclear materials by scrutinizing their ratio of major, minor and trace chemical elements.

Researchers bombard an unknown sample (say, a swipe from an IAEA test) with neutrons from HFIR until a gamma ray is released, creating a unique and detectable "fingerprint" of the sample's fissile material. Matching the evidence to established reference standards identifies the sample's contents.

Currently ORNL's David Glasgow is developing a method to further improve the fingerprint of nuclear isotopes. "The Neutron Activation Analysis Lab [located at HFIR] provides high-fidelity irradiated nuclear forensics materials to the research community," Glasgow said. "In addition, we use specialized nuclear methods that yield bulk and isotopic data of fissile traces to analyze materials of interest to the nuclear forensics and nonproliferation missions."

Meanwhile, NACIL's latest experiment involves advancing procedures for expanded characterizations of spent nuclear fuel. Accurate and comprehensive analyses are vital at all stages of the fuel cycle, and the researchers are developing standards and methods for testing materials based on this work. ORNL computational scientist Ian Gauld, for example, models nuclear fuels and irradiated test materials. He works closely with NACIL scientists examining aging spent nuclear fuel to compare experiment with theory-based calculations to improve predictive models of fuel behavior. Such validation efforts may also help ORNL's radiochemical detectives support future forensics activities.

With the advent of the Ultra-Trace Forensics Science Facility and a multi-sponsored mass spectrometry center at ORNL -- complete with strict clean rooms, a small energy footprint, new protective glove boxes and a walk-in hood for forensic analysis -- there is undeniable potential for a NACIL future that honors its past.

Story Source:  Materials provided by Oak Ridge National Laboratory.  "Cracking cases with nuclear forensics: Specialized team uses nuclear forensics to solve mysteries and safeguard materials." ScienceDaily, 25 January 2016. 
Share:
 /  No comments  / 
, ,

Eyewitness identification reforms may have unintended consequences

Eyewitness identification reforms 
may have unintended consequences

Research by a University of California, Riverside psychologist raises serious questions about eyewitness identification procedures that are being adopted by police departments across the United States.  These new procedures are designed to reduce the kinds of false identification errors that can lead to wrongful convictions of innocent people.

While it has long been held that these changes reduce false identifications with little or no loss of correct identifications, UC Riverside psychology professor Steven E. Clark suggests that that is not the case.

The loss of correct identifications can be significant, Clark says. Importantly, the new procedures may, under some circumstances, lead to identification evidence that is less accurate than the identification evidence from the procedures they are designed to replace. Policymakers need to look very carefully at the data from empirical studies as they consider adopting new procedures, he cautions.

Clark has been involved in more than 200 criminal and civil cases, has consulted with prosecution and defense attorneys, and has testified as an expert in federal and state courts in six states, including California. Much of his research has been funded by the National Science Foundation.

In the paper, the psychologist notes that the reforms are directed at fundamental aspects of the identification process: How lineups are constructed, what witnesses are told and how they are instructed prior to the lineup, the way that the lineup is presented, and what police officers should and should not say and do during the identification procedure.

"Whether policymakers decide to adopt or not adopt these new procedures is up to them," he says. "In order to make those policy decisions, they need to know clearly what the benefits are and what the costs are."

The blind line-up
For some of the new procedures the cost-benefit trade-offs are clear. For other procedures, Clark suggests that the critical research has not been done. For example, one of the new procedures coming into use requires that the police officer who shows the lineup not know which person in the lineup is the suspect. In this "blind" procedure, the police officer would not know whether the suspect was second, third or sixth in the lineup. The blind procedure prevents police officers from deliberately or inadvertently cuing witnesses about who they should pick from the lineup.

"The principle behind blind lineup administration is solid," Clark says. "If the criminal justice system is concerned that the police might inadvertently communicate their expectations to witnesses, then a good solution is for the police to not have expectations by not knowing which person in the lineup is the suspect. However, many ideas that seem right in principle don't actually work, or have unintended side effects. The principle behind the blind lineup may be solid, but solid data would be better."

Clark's research examines the results from dozens of eyewitness identification studies that have been conducted and published over the last 32 years. The trade-off between false identifications avoided versus correct identifications lost is consistent, he says.

This trade-off raises an important question: How many correct identifications is the justice system willing to lose in order to avoid a false identification? Clark explains that under some conditions that trade-off may be very high, with many correct identifications lost for each false identification avoided.

Is that a trade-off that the criminal justice system is willing to accept? It depends, Clark says.

"In our justice system there is a view that a false conviction is a far worse error than a false acquittal," he says. "However, false identifications do not always lead to prosecution or false convictions, and false non-identifications do not always lead to false acquittals. This raises a question about the justice system's ability to correct its mistakes.

"Whether the justice system prefers one eyewitness identification procedure over another depends on many factors, the nature of the trade-off -- for example, how many correct identifications are lost in exchange for each false identification that is avoided -- and what the consequences of those errors are. There are many other considerations as well, in terms of due process and procedural justice. Policymakers have a lot to chew on."

Story Source:  Materials provided by University of California - Riverside, original written by Bettye Miller.  S. E. Clark. Costs and Benefits of Eyewitness Identification Reform: Psychological Science and Public Policy. Perspectives on Psychological Science, 2012.
Share:
 /  No comments  / 

How we get directions wrong

Credit: Kyoto University  
Using virtual three-dimensional mazes together with functional magnetic
resonance imaging (fMRI), researchers from Kyoto University investigated
whether a person's preconceptions could be represented in brain activity.
Ever had the experience of receiving details instructions on how to do something, then get it mixed up and confused?

According to this research out of the University of Kyoto, this confusion may be due to the way our brain maintains our preconceived ideas.  Our preconceived ideas are hard to shake, so we end up mixing up our preconceptions with the instructions.  Result?  Confusion.

So how does this apply to writers?  Suppose you're writing a murder mystery, and your bad guy has an accomplice who is given specific instructions on setting up the bad guy's alibi.  Your detective can't break the bad guy.  But the accomplice?  Did he do exactly as instructed?  Or did he make a mistake?

Or perhaps you're developing an action-adventure plot.  The main character must rely on others to accomplish something.  Given this research, it's natural and normal for someone to intermix instructions with their own preconceived ideas.  Result?  The plan goes wrong.

Here's the report with a link to the full study in the attribution.
*  *  *  *  *


Mazes and brains: When preconception trumps logic
Regions in brain that may lead to new communication tools found

Researchers reconstruct what we see in our minds when
we navigate -- and explain how we get directions wrong.

Rhe regions of the brain responsible for preconception have been found by researchers who have decoded what scenes people picture in their minds. The discovery helps researchers to reconstruct what we see in our minds when we navigate -- and explain how we get directions wrong.

The brain helps us navigate by continually generating, rationalizing, and analyzing great amounts of in-formation. For example, this innate GPS-like function helps us find our way in cities, follow directions to a specific destination, or go to a particular restaurant to satisfy a craving.

"When people try to get from one place to another, they 'foresee' the upcoming landscape in their minds," said study author Yumi Shikauchi. "We wanted to decode prior belief in the brain, because it's so crucial for spatial navigation."

Using virtual three-dimensional mazes together with functional magnetic resonance imaging (fMRI), the researchers investigated whether a person's preconceptions could be represented in brain activity.

Participants were led through each maze, memorizing a sequence of scenes by receiving directions for each move. Then, while being imaged using fMRI, they were asked to navigate through the maze by choosing the upcoming scene from two options. In contrast to methods in previous studies, the re-searchers focused on the underpinnings of expectation and prediction, crucial cognitive processes in everyday decision making.

Twelve decoders deciphered brain activity from fMRI scans by associating signals with output variables. They were ultimately able to reconstruct what scene the participants pictured in their minds as they progressed through the maze.

They also discovered that the human sense of objectivity may sometimes be overpowered by preconception, which includes biases arising from external cues and prior knowledge.

"We found that the activity patterns in the parietal regions reflect participants' expectations even when they are wrong, demonstrating that subjective belief can override objective reality," said senior author Shin Ishii.

Shikauchi and Ishii hope that this research will contribute to the development of new communication tools that make use of brain activity.

"There are a lot of things that can't be communicated just by words and language. As we were able to decipher virtual expectations both right and wrong, this could contribute to the development of a new type of tool that allows people to communicate non-linguistic information," said Ishii. "We now need to be able to decipher scenes that are more complicated than simple mazes."
Story Source:  Materials provided by Kyoto University.  Yumi Shikauchi, Shin Ishii. Decoding the view expectation during learned maze navigation from human fronto-parietal network. Scientific Reports, 2015
Share:
 /  No comments  / 

Write standing: It worked for Woolf. Hemingway. Roth. Why not you?


Thomas Jefferson and his stand-up desk.
Søren Kierkegaard wrote standing.

As did Charles Dickens.

And Winston Churchill.

Philip Roth.

Add to that Vladimir Nabokov and Virginia Woolf.

Plus Ernest Hemingway.

What are we waiting for?
*  *  *  *  *


New study indicates students' cognitive 
functioning improves when using standing desks

Donald Rumsfeld.  (Okay,
so not a writer.  But he
worked standing.)
Do students think best when on their feet? New findings provide the first evidence of neurocognitive benefits of stand-height desks in classrooms. These findings provide the first evidence of neurocognitive benefits of stand-height desks in classrooms, where students are given the choice to stand or sit based on their preferences.

Ranjana Mehta, Ph.D., assistant professor at the Texas A&M School of Public Health, researched freshman high school students with who used standing desks. Testing was performed at the beginning and again at the end of their freshman year.

Winston Churchill.
Through using an experimental design, Mehta explored the neurocognitive benefits using four computerized tests to assess executive functions. Executive functions are cognitive skills we all use to analyze tasks, break them into steps and keep them in mind until we get them done. These skills are directly related to the development of many academic skills that allow students to manage their time effectively, memorize facts, understand what they read, solve multi-step problems and organize their thoughts in writing. Because these functions are largely regulated in the frontal brain regions, a portable brain-imaging device (functional near infrared spectroscopy) was used to examine associated changes in the frontal brain function by placing biosensors on students' foreheads during testing.

"Test results indicated that continued use of standing desks was associated with significant improvements in executive function and working memory capabilities," Mehta said. "Changes in corresponding brain activation patterns were also observed."

Philip Roth working at his lectern.
In earlier studies that primarily focused on energy expenditure, teachers observed increased attention and better behavior of students using standing desks. Mehta's research study is the first study not subject to bias or interpretation that objectively exams students' cognitive responses and brain function while using standing desks.

"Interestingly, our research showed the use of standing desks improved neurocognitive function, which is consistent with results from previous studies on school-based exercise programs," Mehta said. "The next step would be to directly compare the neurocognitive benefits of standing desks to school-based exercise programs."

"There has been lots of anecdotal evidence from teachers that students focused and behaved better while using standing desks," added Mark Benden, Ph.D., CPE, co-researcher and director of the Texas A&M Ergonomics Center. "This is the first examination of students' cognitive responses to the standing desks, which to date have focused largely on sedentary time as it relates to childhood obesity."

Ernest Hemingway at his
typewriter.
Continued investigation of this research may have strong implications for policy makers, public health professionals and school administrators to consider simple and sustainable environmental changes in classrooms that can effectively increase energy expenditure and physical activity as well as enhance cognitive development and education outcomes.
Story Source:  Reprinted from materials provided by Texas A&M University, original written by Rae Lynn Mitchell.  Ranjana Mehta, Ashley Shortz, Mark Benden. Standing Up for Learning: A Pilot Investigation on the Neurocognitive Benefits of Stand-Biased School Desks. International Journal of Environmental Research and Public Health, 2015.

We think better on our feet, literally


A study from the Texas A&M Health Science Center School of Public Health finds students with standing desks are more attentive than their seated counterparts. In fact, preliminary results show 12 percent greater on-task engagement in classrooms with standing desks, which equates to an extra seven minutes per hour of engaged instruction time.

Copyright: Gettyimages
Vladimir Nabokov wrote standing.
The suit and tie is optional.
The findings, published in the International Journal of Health Promotion and Education, were based on a study of almost 300 children in second through fourth grade who were observed over the course of a school year. Engagement was measured by on-task behaviors such as answering a question, raising a hand or participating in active discussion and off-task behaviors like talking out of turn.

Standing desks -- also known as stand-biased desks -- are raised desks that have stools nearby, enabling students to sit or stand during class at their discretion. Mark Benden, Ph.D., CPE, associate professor at the Texas A&M Health Science Center School of Public Health, who is an ergonomic engineer by trade, originally became interested in the desks as a means to reduce childhood obesity and relieve stress on spinal structures that may occur with traditional desks. Lessons learned from his research in this area led to creation of Stand2Learn™, an offshoot company of a faculty-led startup that manufactures a classroom version of the stand-biased desk.

Benden's previous studies have shown the desks can help reduce obesity -- with students at standing desks burning 15 percent more calories than students at traditional desks (25 percent for obese children) -- and there was anecdotal evidence that the desks also increased engagement. The latest study was the first designed specifically to look at the impact of classroom engagement.

Benden said he was not surprised at the results of the study, given that previous research has shown that physical activity, even at low levels, may have beneficial effects on cognitive ability.

"Standing workstations reduce disruptive behavior problems and increase students' attention or academic behavioral engagement by providing students with a different method for completing academic tasks (like standing) that breaks up the monotony of seated work," Benden said.

"Considerable research indicates that academic behavioral engagement is the most important contributor to student achievement. Simply put, we think better on our feet than in our seat."

demoforpost.tk

Taking the standing thing too far?  Not if it powers your equipment.

The key takeaway from this research, Benden said, is that school districts that put standing desks in classrooms may be able to address two problems at the same time: academic performance and childhood obesity.
Story Source:  Materials provided by Texas A&M University, original written by Ellen Davis. Marianela Dornhecker, Jamilia J. Blake, Mark Benden, Hongwei Zhao, Monica Wendel. The effect of stand-biased desks on academic engagement: an exploratory study. International Journal of Health Promotion and Education, 2015.
Share:
 /  No comments  / 
, ,

How to use eyewitness identifications: Cautiously

As a science geek, I do watch the many true-crime shows, especially those that rely on forensic science to identify and convict culprits.  But as this latest series of reports indicate, the science isn't perfect, in fact in some cases, the science is plainly flawed.

Fortunately, researchers and defense attorneys are aware of the flaws and can use this information to help protect the truly innocent.

Here's another report on a flaw in forensics with suggestions on how to correctly us eyewitness testimony.  The full report is available in the attribution line.
*  *  *  *  *

Using eyewitness identifications: 
New report urges caution

A new report from the National Research Council recommends best practices that law enforcement agencies and courts should follow to improve the likelihood that eyewitness identifications used in criminal cases will be accurate. Science has provided an increasingly clear picture of the inherent limits in human visual perception and memory that can lead to errors, as well as the ways unintentional cues during law enforcement processes can compromise eyewitness identifications, the report says.

"Human visual perception and memory are changeable, the ability to recognize individuals is imperfect, and policies governing law enforcement procedures are not standard -- and any of these limitations can produce mistaken identifications with serious consequences," said Thomas Albright, director of the Vision Center Laboratory at the Salk Institute for Biological Studies and co-chair of the committee that wrote the report. The report focuses on identifications of strangers rather than of family members or others well-known to the witness.

Problems with eyewitness identifications have long been documented, and many of the cases in which DNA evidence later exonerated an innocent person involved at least one mistaken eyewitness. Research in recent decades has revealed many factors that can lead to such mistaken identifications, the report says. Conditions during the commission of the crime such as dim lighting, brief viewing times, stress, or the presence of a visually distracting element such as a gun or knife can influence people's perceptions. Gaps in sensory input are filled by expectations that are based on an individual's prior experiences with the world, which can bias perceptions. Studies also have shown that eyewitnesses are more likely to make mistakes when making an identification among people of another race rather than when making an identification of a person from the eyewitness's own race.

In addition, memory is often an unfaithful record of what was perceived through sight; people's memories are continuously evolving. As memories are processed, encoded, stored, and retrieved, many factors can compromise their fidelity to actual events. Although the individual may be unaware of it, memories are forgotten, reconstructed, updated, and distorted.

Standardized Procedures for Eyewitness IDs Needed
The law enforcement community, while operating under considerable pressure and with limited resources, is already working to improve the accuracy of eyewitness identifications, the report says. However, these efforts have not been uniform and often fall short because of insufficient training, the absence of standard operating procedures, and the presence of actions and statements that unintentionally influence eyewitnesses.

Caution should be exercised in using eyewitness identification procedures and when relying on these identifications in court, the report says. For example, police departments should implement standardized procedures for handling lineups, including using "double-blind" processes to prevent cues and biases from creeping in. Judges should ensure, through expert testimony or jury instructions, that jurors understand factors that may affect the accuracy of an eyewitness identification in a particular case.

Many police departments have begun to use sequential lineups -- in which the witnesses are shown one person or photo at a time -- instead of simultaneous lineups, which show several people or photos at once. However, additional research is needed to determine which procedure is superior, the report says. It recommends the establishment of a National Research Initiative on Eyewitness Identification to better understand best practices for conducting lineups and photo arrays, assessing witnesses' confidence levels, and understanding other aspects of eyewitness identifications.

"At this point, more research needs to be done to tell us whether sequential or simultaneous lineups are more effective at producing accurate identifications," said co-chair Jed Rakoff, senior judge on the U.S. District Court for the Southern District of New York. "But there are many practices that have been validated by scientific methods and research that we already know can reduce the likelihood of erroneous identifications, and law enforcement agencies and courts should implement and follow them consistently."

Best Practices for Law Enforcement
To increase the likelihood of accuracy in eyewitness identifications, the report recommends that law enforcement agencies use the following practices in handling eyewitness identifications.

  • Train all law enforcement officers in eyewitness identification. An eyewitness's memory of an incident can be contaminated by a wide variety of influences, including interaction with the police. All law enforcement agencies should provide their officers and agents with training about vision and memory, practices for minimizing contamination, and effective eyewitness identification protocols. Police officers should be trained to ask open-ended questions, avoid suggestiveness, and efficiently manage scenes with multiple witnesses (for example, minimizing interactions among witnesses).
  • Implement double-blind lineup and photo array procedures. Even if a line-up administrator doesn't verbally tell the witness which person in a lineup or photo array is the suspect, he or she could still convey the suspect's identity through unintended body gestures, facial expressions, or other nonverbal cues. Using a double-blind procedure, in which neither the witness nor the administrator knows which person in the lineup or photo array is the suspect, can avoid this inadvertent bias.
  • Develop and use standardized witness instructions. The report recommends the development of a standard set of easily understood instructions to use when engaging a witness in an identification procedure. Witnesses should be instructed that the perpetrator may or may not be in the photo array or lineup and that, regardless of whether the witness identifies a suspect, the investigation will continue. Such instructions should be used consistently in all photo arrays and lineups and could either be pre-recorded or read aloud by administrators.
  • Document witness confidence judgments. Evidence indicates that an eyewitness's level of confidence in their identifications at the time of trial is not a reliable predictor of their accuracy. The relationship between confidence and accuracy is likely to be strongest at the time of initial identification. Law enforcement should document the witness's level of confidence verbatim at the time when she or he first identifies a suspect.
  • Videotape the witness identification process. To obtain and preserve a permanent record of the conditions associated with the initial identification, the committee recommended that video recording of eyewitness identification procedures become standard practice.

Best Practices for Courts
The federal standard governing the admissibility of eyewitness testimony is set forth in the Manson vs. Braithwaite test under the Due Process Clause of the U.S. Constitution. But the test was set out in 1977 before much of the applied research on eyewitness identification had been conducted, and it includes factors that are not diagnostic of reliability. The best guidance for legal regulation of eyewitness identification evidence comes not from constitutional rulings but from the careful use and understanding of scientific evidence, the report says. It recommends best practices for judges to follow in assessing and using eyewitness testimony.

  • Conduct pre-trial judicial inquiry. Judges have an obligation to ensure the reliability of evidence presented at a trial and should make basic inquiries about eyewitness identification evidence being offered. When assessing the reliability of an eyewitness identification, it is important to know which eyewitness identification procedures the agency had in place and the degree to which they were followed. If indicators of unreliable eyewitness identifications are present, judges should follow applicable procedural law in deciding whether to exclude the identifications or use a lesser sanction. A judge could limit portions of the eyewitness's testimony, for example, or ensure that the jury is provided with a scientific framework within which to evaluate the evidence.
  • Make juries aware of prior identifications. The accepted practice of in-court eyewitness identifications can influence juries in ways that cross-examination, expert testimony, or jury instructions are unable to counter effectively. Moreover, the passage of time since the initial identification may mean that a courtroom identification is a less accurate test of an eyewitness's memory. Whenever the eyewitness identifies a suspect in the courtroom, juries should hear detailed information about any earlier identification, including the procedures used and the confidence expressed by the witness at that time. An eyewitness identification should not typically occur for the first time in a courtroom.
  • Use scientific framework expert testimony. Many scientifically established aspects of eyewitness memory are counterintuitive and may defy expectations, and jurors need assistance in understanding the factors that may affect the accuracy of an identification. In many cases this information can be most effectively conveyed by expert testimony. Judges should have the discretion to allow expert testimony explaining relevant research on eyewitness memory and identifications. Local jurisdictions should make efforts to ensure that defendants receive funding to obtain access to qualified experts.
  • Use jury instructions as an alternative means to convey information. These instructions can be used as an alternative way to convey information about eyewitness identification factors the jury should consider. Jury instructions should, in clear language, explain the relevant principles, allowing judges to focus the instructions on factors relevant to the specific case. Appropriate legal organizations, together with law enforcement, prosecutors, defense counsel, and judges, should convene a body to establish model jury instructions regarding eyewitness identifications.

Related stories:

Story Source: Materials provided by National Academy of Sciences. "Using eyewitness identifications: New report urges caution." ScienceDaily, 2 October 2014. 
Share:
 /  No comments  / 

Forensic sciences 'fraught with error'

Forensic sciences are 'fraught with error'

"People tend to seek, perceive, interpret, and create new 
evidence in ways that verify their preexisting beliefs."

Researchers review various high-profile false convictions and provide an overview of classic psychological research on expectancy and observer effects and indicates in which ways forensic science examiners may be influenced by information such as confessions, eyewitness identification, and graphical evidence.

A target article recently published in Journal of Applied Research in Memory and Cognition (JARMAC) reviews various high-profile false convictions. It provides an overview of classic psychological research on expectancy and observer effects and indicates in which ways forensic science examiners may be influenced by information such as confessions, eyewitness identification, and graphical evidence.

Objective evidence is actually subjective
The target article authors, Saul Kassin and Jeff Kukucka, of John Jay College of Criminal Justice, and Itiel Dror, University College, London, point out that when the instrument of analysis is a human examiner, then even evidence considered by the public to be highly objective, such as fingerprint evidence, is actually subjective in its judgment. Therefore, they argue, there is a potential for confirmation bias because psychological research shows that "people tend to seek, perceive, interpret, and create new evidence in ways that verify their preexisting beliefs."

The authors reveal that even DNA evidence, more famously known for exonerating wrongfully convicted people, has contributed to false convictions, especially when other, flawed, evidence chronologically precedes it, such as a mistaken eyewitness identification or false confession.

"Popular TV programs, such as CSI: Crime Scene Investigation, communicate a false belief in the powers of forensic science, a problem that can be exacerbated when forensic science experts overstate the strength of the evidence," explained leading author, Saul Kassin.

The study does not just point out flaws -- it details many things that can be done to limit or avoid these problems, both during an investigation and during a trial. The authors propose various best practice recommendations to reduce confirmation biases. During the investigation, for example, an easy solution would be to shield forensic examiners from everything other than the evidence they are examining. This minimizes chances of fitting the evidence to a known suspect.

"The target article describes an important force that has the potential to erode the quality of our judicial system. Solving the problem will require psychological researchers, legal scholars and forensic scientists communicating with one another - a process that is fostered by the exchange of ideas," says Ronald Fisher, Editor-in-Chief of JARMAC, and Professor of psychology at Florida International University.

Story Source:  Materials provided by Elsevier. Saul M. Kassin, Itiel E. Dror, Jeff Kukucka. The forensic confirmation bias: Problems, perspectives, and proposed solutions. Journal of Applied Research in Memory and Cognition, 2013 
Share:
 /  No comments  / 
, ,

Bite-mark analysis can lead to false convictions

www.pjstar.com

At least 24 men convicted or charged with murder or rape based on bite
marks on the flesh of victims have been exonerated since 2000, many
after spending more than a decade in prison. Source: The Peoria Journal Star.  
Bite-mark analysis can lead to false convictions

Since 2000, at least 25 people convicted on bite-mark evidence 
have been exonerated due to advances in DNA testing.

Forensic science is a vital crime-fighting tool in today's criminal justice system. But it can also lead to false convictions, according to H. David Sheets, PhD. Landmark research by the Canisius College physics professor proves that bite-mark analysis is "far from an exact science."

Bite-mark analysis compares the teeth of crime suspects to bite-mark patterns on victims. Historically, forensic odontologists (dentists who provide forensic dental identifications in criminal investigations and mass disasters) operate under two general guidelines when interpreting bite-mark evidence. First, that everyone's dental impression is unique to the individual, "similar to fingerprints," Sheets explains. Second, that human skin -- the most common material on which a bite mark is inflicted -- reliably records an individual's dental impression.

Bite-mark analysis is widely accepted in criminal courts and often presented as key evidence in prosecutions. "People assume that it's close to fingerprints in terms of accuracy," Sheets says. "But the notions that a person's dentition is unique or that the human skin can accurately record an individual's bite mark have never been validated scientifically."

Sheets and his colleagues, Mary A. Bush, DDS and Peter J. Bush, from the University at Buffalo (UB) School of Dental Medicine, sought to do just that.

Using a variety of dental impressions, they examined more than 1,000 human dentitions and studied hundreds of bite marks in cadaver skin. With the help of computer analysis and applied statistics, the team then worked to match its database of bite marks to the correct dental impressions.

"When the dental alignments were similar, it was difficult to distinguish exactly which set of teeth made which bites," Sheets says. "That tells us that a single bite mark is not distinct enough to be linked to a specific individual. It can actually point to many different individuals." This means that a false identification is possible, which can lead a police investigation away from the real perpetrator and toward an innocent individual.

The Canisius-UB studies are among the largest conducted on bite-mark analysis and the first to use human-skin models (rather than animal models, wax or Styrofoam). More notable is that its findings call into question criminal convictions that rested entirely on bite-mark evidence.

Since 2000, at least 25 people convicted on bite-mark evidence have been exonerated due to advances in DNA testing, according to the Innocence Project. The national organization, which works to free wrongfully convicted individuals, is now using the Canisius-UB studies to help build a case for having bite-mark evidence cast out of criminal proceedings.

"This is an example of where science can help prevent future wrongful convictions and perhaps even provide some social justice to those already convicted," Sheets concludes.

In addition to Sheets' research on bite-mark analysis, he is a member of the Expert Working Group on Human Factors in Handwriting Analysis. Appointed by the National Institute of Standards and Technology (NIST) and the National Institute of Justice (NIJ), which provide oversight to the federal forensic community, the Expert Working Group on Handwriting Analysis is one of several discipline-specific groups charged with identifying the human factors that affect the outcomes of forensic analyses and developing best practices, based on scientific research, that will reduce the likelihood of errors in the future.

Related stories:
Story Source:  Materials provided by Canisius College.  "Bite-mark analysis can lead to false convictions, landmark research shows." ScienceDaily, 8 January 2016.
Share:
 /  No comments  / 

Why superstitions are hard to shake

www.ebay.tv
The power of magical thinking:
Why superstitions are hard to shake

When sports fans wear their lucky shirts on game day, they know it is irrational to think clothing can influence a team's performance. But they do it anyway.  Even smart, educated, emotionally stable adults believe in superstitions they recognize are unreasonable.

In a paper from the University of Chicago Booth School of Business, to be published in an upcoming issue of Psychological Review, Associate Professor Jane Risen finds that even when people recognize that their belief does not make sense, they can still allow that irrational belief to influence how they think, feel and behave.

In "Believing What We Don't Believe: Acquiescence to Superstitious Beliefs and Other Powerful Intuitions," Risen contends that detecting an irrational thought and correcting that error are two separate processes, not one as most dual-system cognitive models assume. This insight explains how people can detect irrational thought and choose not to correct it, a process she describes as "acquiescence."

"Even when the conditions are all perfect for detecting an error -- when people have the ability and motivation to be rational and when the context draws attention to the error -- the magical intuition may still prevail," said Risen.

Although the suggestion to decouple detection and correction was inspired by the findings from research on superstition and magical thinking, Risen suggests there are broader applications. Understanding how acquiescence unfolds in magical thinking can help provide insight into how it is that people knowingly behave irrationally in many other areas of life.

Certain variables create situations in which intuition is likely to override rational thought. For example, people may acquiesce if they can rationalize their intuition by thinking that a particular situation is special. Acquiescence may also be more likely if the costs of ignoring rationality are low relative to the costs of ignoring intuition -- as with people who receive a chain letter; they acknowledge it is irrational to believe that breaking the chain brings bad luck, but still forward the letter.

The research has implications for how people make decisions at home, at work and in public life. It also suggests how to help people fix their errors. Interventions to effectively change behavior need to target the appropriate cognitive process, which Risen suggests starts by acknowledging that detection and correction are separate processes.

Related stories:
Story Source:  Materials provided by University of Chicago Booth School of Business.  "The power of magical thinking: Why superstitions are hard to shake." ScienceDaily, 9 November 2015. 
Share:
 /  No comments  / 

Religious beliefs don't always lead to violence

Yesterday, a woman in Muslim garb was escorted out of a political rally sponsored by a leading candidate for office - for the only reason of her clothing.  As she exited, she was loudly booed and subjected to intolerant cat-calls.

Not a pretty event.

Is there a better way?  Can we learn to be more tolerant of other's political, ethnic, and religious views?

According to these two reports, the answer is yes, and that the solution is within us.

Read the reports of these studies, and consider how reviewing your own religious or ethical beliefs can change the way you respond to people of a different race or that hold different views than yourself.

Here are the reports, with links to the full studies in the attributions.
*  *  *  *  *

Religious beliefs don't always lead to violence
Study shows thinking from God's perspective can reduce bias against others

From the Christian Crusades to the Paris attacks, countless conflicts and acts of violence have been claimed to be the result of differing religious beliefs. These faith-based opinions are thought to motivate aggressive behavior because of how they encourage group loyalty or spin ideologies that devalue the lives of non-believers. However, new research reveals the opposite: religious beliefs might instead promote interfaith cooperation.

Religious beliefs might promote interfaith cooperation
However, new research published in the Proceedings of the National Academy of Sciences (PNAS) reveals the opposite: religious beliefs might instead promote interfaith cooperation. Researchers from the New School for Social Research and Carnegie Mellon University examined how Palestinian youth made moral choices, from their own perspectives and from the perspective of Allah. The results showed that Muslim-Palestinians believed that Allah preferred them to value the lives of Palestinians and Jewish-Israelis more equally, raising the possibility that beliefs about God can mitigate bias against other groups and reduce barriers to peace.

"Our findings are important because one precursor to violence is when people believe that the lives of members of their group are more important than the lives of members of another group. Here, we show that religious belief -- even amidst a conflict centered on religious differences -- can lead people to apply universal moral principles similarly to believers and non-believers alike," said Jeremy Ginges, associate professor of psychology at the New School for Social Research.

For the study, 555 Palestinian adolescents between the ages of 12 and 18 were presented with a classic "trolley dilemma" that involved a Palestinian man being killed to save the lives of five children who were either Jewish-Israeli or Muslim-Palestinian. The participants responded from their own perspective and from Allah's perspective.

The results showed that although Muslim-Palestinian participants valued their own group's lives over Jewish-Israeli lives, they believed that Allah preferred them to value the lives of members of both groups more equally. In fact, thinking from Allah's perspective decreased the bias toward their own group by almost 30 percent.

"Beliefs about God seem to encourage an application of universal moral rules to believers and non-believers alike, even in a conflict zone. Thus, it does not seem to be beliefs about God that lead to outgroup aggression," said Nichole Argo, a research scientist in engineering and public policy and social and decision sciences at Carnegie Mellon.

"There may be other aspects of religion that lead to outgroup aggression. For instance, other work done in conflict zones has identified participation in collective religious rituals and frequent attendance at a place of worship to be associated with support for violence. This study, however, adds to a growing literature on how religious belief can increase cooperation with people from other faiths," Argo said.
Story Source:  Materials provided by Carnegie Mellon University.  Jeremy Ginges, Hammad Sheikh, Scott Atran, Nichole Argo. Thinking from God’s perspective decreases biased valuation of the life of a nonbeliever. Proceedings of the National Academy of Sciences, 2015



Reminding people of their religious
belief system reduces hostility

New research may shed some light on religion's actual influence on believers -- and the news is positive. Researchers hypothesized that being reminded of religious beliefs would normally promote less hostile reactions to the kinds of threats in everyday life that usually heighten hostility. Across nine different experiments with 910 participants, the results consistently supported the hypothesis for Christians, Jews, Muslims and Hindus alike. The religiously reminded were significantly less hostile.

Few topics can prove more divisive than religion, with some insisting it promotes compassion, selflessness and generosity, and others arguing that it leads to intolerance, isolation and even violence.

"Based on our premise that most people's religious beliefs are non-hostile and magnanimous, we hypothesized that being reminded of religious beliefs would normally promote less hostile reactions to the kinds of threats in everyday life that usually heighten hostility," says researcher Karina Schumann, the article's lead author, now a postdoctoral fellow at Stanford University.

To test this hypothesis, participants either received a simple reminder of their religious belief system ("which religious beliefs system do you identify with?") or not. They were then exposed to either threatening experiences (such as thinking about their own death or failing at an academic assignment) or not. They were then given a chance to judge and assign punishments for transgressors, criminals and worldview critics.

Across nine different experiments with 910 participants, the results consistently supported the hypothesis for Christians, Jews, Muslims and Hindus alike. The religiously reminded were significantly less hostile and punitive in the threatening circumstances than the non-reminded participants were (there were no effects of the religious reminders among the non-threatened participants).

"Our research suggests that people generally associate their religious beliefs with Golden Rule ideals of forgiveness and forbearance, and that they turn to them when the chips are down, in threatening circumstances," says York U psychology professor Ian McGregor, the article's second author. "This research contributes to the current dialogue on religion by demonstrating that even brief religious belief reminders not accompanied by any explicit beliefs or injunctions tend to promote more magnanimous, less hostile choices in threatening circumstances."

Though the researchers say the link between religion and magnanimity may seem surprising given that news headlines so often focus on terrorist attacks and other atrocities committed in the name of religion, their results suggest that for most people, the influence of religion may be more positive than what is often portrayed in the media.

"Part of the reason for our magnanimity finding could be that in our research we focused on religious ideals, whereas extremist groups may often be more focused on intergroup rivalries and coalitions than the core religious ideals of love and forgiveness," says Schumann. "Future research is needed to determine whether reminders of religious belief can also foster magnanimity in non-Western countries, among less educated individuals, and in the context of high-stakes conflicts in which transgressions are committed by others with competing religious convictions."
Story Source:  Materials provided by York University.  Karina Schumann, Ian McGregor, Kyle A. Nash, Michael Ross. Religious magnanimity: Reminding people of their religious belief system reduces hostility after threat. Journal of Personality and Social Psychology, 2014.
Related stories:
Share:
 /  No comments  / 

Reading Fiction: Zoning out or deep thinking?

Credit: © Sergey Nivens / Fotolia  
(Stock image)

Real-time brain scans show that when people read stories that deal with these
core, protected values, the "default mode network" in their brains activates. 

Zoning out or deep thinking?

Reading stories about values you hold sacred activates a part of your brain once thought to be used for zoning out. The researchers suggest that these results were gained not just because the brain is presented with a moral quandary, but rather that the quandary is presented in a narrative format.

Everyone has at least a few non-negotiable values. These are the things that, no matter what the circumstance, you'd never compromise for any reason -- such as "I'd never hurt a child," or "I'm against the death penalty."

Real-time brain scans show that when people read stories that deal with these core, protected values, the "default mode network" in their brains activates.

Working to find meaning in narratives
This network was once thought of as just the brain's autopilot, since it has been shown to be active when you're not engaged by anything in the outside world -- but studies like this one suggest that it's actually working to find meaning in the narratives.

"The brain is devoting a huge amount of energy to whatever that network is doing. We need to understand why," said Jonas Kaplan of the USC Dornsife Brain and Creativity Institute. Kaplan was the lead author of the study, which was published on Jan. 7 in the journal Cerebral Cortex.

Kaplan thinks that it's not just that the brain is presented with a moral quandary, but rather that the quandary is presented in a narrative format.

"Stories help us to organize information in a unique way," he said.

To find relevant stories, the researchers sorted through 20 million blog posts using software developed at the USC Institute for Creative Technologies.

"We wanted to know how people tell stories in their daily lives. It was kind of like finding stories in their natural habitat," said Kaplan, assistant research professor of psychology at the Brain and Creativity Institute at the USC Dornsife College of Letters, Arts and Sciences.

That 20 million was pared down to 40 stories that each contained an example of a crisis involving a potentially protected value: cheating on a spouse, having an abortion, crossing a picket line, or getting in a fight.

Those stories were translated into Mandarin Chinese and Farsi, and then read by American, Chinese and Iranian participants in their native language while their brains were scanned by fMRI. They also answered general questions about the stories while being scanned.

Stories that participants said involved values that were protected to them activated the default mode network in their brain to a greater degree. In addition, the level of activation varied from culture to culture. On average, Iranians showed the greatest level of activation in the study, while the Chinese participants showed the least.

"Stories appear to be a fundamental way in which the brain organizes information in a practical and memorable manner. It is important to understand the neural mechanisms required to do this, and this study is a step in that direction," said Antonio Damasio, senior author of the study. Damasio is co-director of the Brain and Creativity Institute, holder of the David Dornsife Chair in Neuroscience and a professor of psychology and neurology.

It's not yet clear whether a value either is or is not protected, or whether the sacredness of a value is on a sliding scale. But in a nation where political beliefs are growing more polarized and entrenched, it's important to understand what biological processes lie at the root of these values, Kaplan said.

"People will often hold political values as protected values and protected values are at the root of many political conflicts around the world, which is why they're interesting to us," he said.

Related stories:


Story Source: Materials provided by University of Southern California. Jonas T. Kaplan, Sarah I. Gimbel, Morteza Dehghani, Mary Helen Immordino-Yang, Kenji Sagae, Jennifer D. Wong, Christine M. Tipper, Hanna Damasio, Andrew S. Gordon, and Antonio Damasio. Processing Narratives Concerning Protected Values: A Cross-Cultural Investigation of Neural Correlates. Cerebral Cortex, January 2016
Share:
 /  No comments  / 

Understanding your character's sixth-sense for danger: Here's how it works.

Credit: © Dario Lo Presti / Fotolia

Anxious individuals detect threat in a different region of the
brain from people who are more laid-back.
Characters having a sixth-sense for danger borders on cliché, a trope even.

Yet, many if not most clichés are a statement of the obvious.  We as humans do have a sixth sense for danger, and as with most characteristics some of us have a sharper sense of impending danger, and some have less.

Researchers in France are investigating the relationship between this sixth-sense and anxiety, how it functions in different people, and when it is a healthy reaction and when it's not.

Is this sixth-sense extra-sensory?  Not from what I understand about brain science.  Significant research using fMRI and other technology reveals that most processing in our brain takes place out of the notice of our conscious mind, and alerts us to a potential threat in far less time than our conscious mind can register.

So when a section of our brain notes an angry look on the face of someone staring directly at us in a social situation, we feel anxious.  This is our subconscious mind alerting us to potential danger so that our conscious mind can work to identify the threat.
*  *  *  *  *


Being anxious could be good for you in a crisis
Brain prioritizes threats, especially in anxious people

Seeing anger paired with a direct gaze produces 
a response in the brain in only 200 milliseconds.

New findings could help explain the apparent 'sixth sense' we have for danger in social situations, with the direction of a person's gaze being a crucial cue. People with non-clinical anxiety are particularly well poised for action.

The results in the journal eLife may help explain the apparent "sixth sense" we have for danger. This is the first time that specific regions of the brain have been identified to be involved in the phenomenon. The human brain is able to detect social threats in these regions in a fast, automatic fashion, within just 200 milliseconds.

Even more surprising for the scientists was the discovery that anxious individuals detect threat in a different region of the brain from people who are more laid-back. It was previously thought that anxiety could lead to over-sensitivity to threat signals. However, the new study shows that the difference has a useful purpose.
  • Anxious people process threats using regions of the brain responsible for action. 
  • Meanwhile, 'low anxious' people process them in sensory circuits, responsible for facial recognition.
Facial displays of emotion can be ambiguous but the researchers managed to identify what it is that makes a person particularly threatening. They found that the direction a person is looking in is key to enhancing our sensitivity to their emotions. Anger paired with a direct gaze produces a response in the brain in only 200 milliseconds, faster than if the angry person is looking elsewhere.

"In a crowd, you will be most sensitive to an angry face looking towards you, and will be less alert to an angry person looking somewhere else," says lead author Marwa El Zein from the French Institute of Health and Medical Research (INSERM) and the Ecole Normale Supérieurein Paris.

Seeing fear in others triggers our sixth-sense
Similarly, if a person displays fear and looks in a particular direction you will detect this more rapidly than positive emotions. Such quick reactions could have served an adaptive purpose for survival. For example, we evolved alongside predators that can attack, bite or sting. A rapid reaction to someone experiencing fear can help us avoid danger.

"In contrast to previous work, our findings demonstrate that the brain devotes more processing resources to negative emotions that signal threat, rather than to any display of negative emotion," says El Zein.

Electrical signals measured in the brains of 24 volunteers were analysed while they were asked to decide whether digitally altered faces expressed anger or fear. Some faces displayed exactly the same expression, but the direction of their gaze was altered. A total of 1080 trials were carried out.

It has often been theorized that elevated anxiety, even in a non-clinical range, could impair the brain's processing of threats. However, El Zein and her co-authors instead found that non-clinical anxiety shifts the neural 'coding' of threat to motor circuits, which produce action, from sensory circuits, which help us to recognize faces. The researchers note that it would be interesting to determine whether the same is true for people with anxiety scores in the clinical range.

Story Source:  Materials provided by eLife.  Marwa El Zein, Valentin Wyart, Julie Grèzes. Anxiety dissociates the adaptive functions of sensory and motor response enhancements to social threats. eLife, 2015.
Share:
 /  No comments  / 
Subscribe to: Posts (Atom)