Category: Neuroscience Page 12 of 15

Aphasia: Acceptance, Hope, Purpose

On March 11, 2014

In Behavior/Psychology, Biology, Neuroscience, Science Communication & Education

By Sonal Gagrani

Imagine having a head full of things to say, but not being able to articulate them. This is the life of Carl McIntyre.

courtesy of aphasiathemovie.com

There is a three-hour window of opportunity after the initiation of a stroke in which it can be effectively treated. However, when a stroke hit Carl McIntyre, those three hours passed before he could be safely withdrawn from danger. His ability to speak and understand became heavily impaired, a condition known as aphasia. In order to raise awareness of this condition that affects not only him, but almost 40% of the people who suffer a stroke, he starred as himself in a film called Aphasia. Carl McIntyre came himself to speak at Duke for Brain Awareness Week following a screening of his film.

Aphasia is a group of communication disorders that affect the language centers of the brain causing impairments in speech, speech comprehension, reading and writing. It tends to arise with damage of some part of the brain, often due to a stroke, brain tumors, or neurodegenerative diseases.

McIntyre expressed powerfully that, “what happens to one, happens to two.” The aphasia affects not only him but his entire family. Life felt as if it was over, loving was difficult; he felt “trapped inside of his head.” Having a reservoir full of thoughts that he was unable to empty due to this inability to communicate could be eternally frustrating. Aphasia patients often are cognitively intact, but have trouble expressing what they want to say. McIntyre occasionally used a whiteboard to write down words he was struggling to say or stumbled on the first sounds of words.

Carl McIntyre But rather than letting the aphasia control the way that he lived, McIntyre worked hard to restore his language capabilities and spread awareness of the challenges that inflicted individuals must face. Most importantly, McIntyre expressed the importance of keeping hope.

He explained that the first step to having a positive outlook on his condition was to accept the “old Carl was dead.” The next was to keep hope that his life could continue as normal as possible – that the condition would not impair his lifestyle. Last, he expressed the importance of having a sense a purpose by picking up hobbies and not losing all meaning in life. Carl strives to have a strong sense of self despite the adversities he and his family has had to face and inspires others to understand and do just this.

Music, the Brain and Jimi Hendrix

By Ashley Mooney

On March 10, 2014

In Biology, Faculty, Lecture, Neuroscience

By Ashley Mooney

Hearing music and moving to it are more connected than you’d think.

Richard Mooney and one of his research subjects. (Photo – Duke Magazine)

Neurobiologists have traditionally viewed human responses to sound as reflexive.

But in fact, perception of sound and music can be viewed as much more dynamic, said Richard Mooney, George Barth Geller professor of neurobiology and classically-trained guitarist. Rather than speaking in a typical lecture hall, Mooney presented his research in Motorco Music Hall.

“In the classic view of how the nervous system works, there’s a sensory stimulus in the world that excites our sensory receptors and then we behave,” Mooney said. “This can’t be so. We don’t live in a reflexive experience. We’re living in a state where we’re present in the moment.”

Using a video of musician Jimi Hendrix’s performance of “Johnny B. Goode,” Mooney illustrated the connection between the motor system and the auditory cortex.

“Hendrix is anticipating all these dynamics in music, moving his body in a way to accentuate it,” Mooney said. “It’s a really good example of how our brain must be forecasting the sound it wants to make or the sound it wants to experience.”

Mooney cited a study in which trained keyboard players were asked either to listen to music without making physical movements or to play a piece without being able to hear it. Using functional MRI, researchers found that the auditory cortex, the supplementary motor area and the premotor cortex of the brain all receive more oxygen than other sections during either task, implying a connection between the systems.

“Music isn’t passive. Even when we’re listening, it’s engaging not only the biological amplifier in our ear, but also this really complex network of sensory motor structures in our brain,” Mooney said.

800px-Uncoiled_cochlea_with_basilar_membrane

An uncoiled cochlea with the basilar membrane. Courtesy of Wikimedia commons.

A part of the inner ear called the cochlea functions as an acoustical prism, splitting complex sounds into an array of simpler, tone-like components.

“The lens of our eye focuses stimuli in a way that’s Cartesian,” Mooney said. “In contrast, what our ear has to do is really take a mismatched pattern of energy that’s vibrating in our eardrum and decompose it into simpler components.”

People have biological amplifiers deep in their cochlea that allow them to perceive and interpret speech and music. Average-volume speech usually causes the basilar membrane, a structure in the inner ear, to vibrate within a very small distance—approximately the diameter of a gold atom. Mooney noted that the level of vibration indicates that the membrane moves about 100-fold more than it would if the system were purely passive.

The cochlea even vibrates in deaf ears, just not to the same extent. But much of a person’s ability to hear, that is to discern differences in pitch and the nuances of spoken language, also rely on hair cells within the ear.

“These aren’t the things responsible for your grandfather’s tufts of hair that are coming out of his ears,” Mooney said. “These are all a special kind of nerve cell called a receptor cell.”

Even though all people have connections between their motor and auditory systems and may understand the connections conceptually, musicians and those who frequently practice making music can usually predict upcoming tones with more accuracy.

He provided the example of basketball players shooting free throws. If shown video clips of a person shooting a free throw, but not the final trajectory, only professional players can accurately predict whether the ball went into the basket. Sportscasters and audience members cannot accurately predict baskets, even if they are highly exposed to watching the actions.

The lecture was part of Brain Awareness Week, a global campaign to encourage public interest in the progress and benefits of brain research. Mooney noted that Brain Awareness Week helps him gain a different perspective on his research.

“Scientists hang out with themselves in their labs and they ask each other these really sort of pointy headed questions all the time,” he said. “They don’t get a lot of chances to hear from people who have really different perspectives.”

The final event in the series was a hands-on demonstration at the Museum of Life and Science, Saturday from 1 to 4 p.m.

My Brain and Your Brain Speak Different Languages

By Clara Colombatto

On March 5, 2014

In Behavior/Psychology, Faculty, Lecture, Medicine, Neuroscience, Science Communication & Education

By Clara Colombatto

The fact that “different people speak language differently” is one of the major challenges in uncovering the neural basis of language. Brain structure and function differ highly among individuals, and this is the core of the new discipline of cognitive neurolinguistics. Duke professor Edna Andrews explained the fascinating complexity of language research at the Regulator Bookshop on Tuesday, March 4.

Edna Andrews gives an overview of the new field of cognitive neurolinguistics at the Regulator Bookshop for Brain Awareness Week Credit: Clara Colombatto

Edna Andrews gives an overview of the new field of cognitive neurolinguistics at the Regulator Bookshop for Brain Awareness Week (Photo: Clara Colombatto)

A linguist by training, Edna Andrews is the Nancy & Jeffrey Marcus Distinguished Professor of Slavic & Eurasian Studies, Chair of the Linguistics Program and holds appointments in Cultural Anthropology and the Duke Institute for Brain Sciences. Over time, Andrews’s research interests led her to neuroscience — so she went back to the classroom, studied as a beginning student with neurobiologist Gillian Einstein and shadowed a team of neurosurgeons at Duke Hospital.

This range of disciplines is fundamental for Andrews’ pioneering work in the field of cognitive neurolinguistics. Observations of brain-damaged patients led to a 19^th century model that held that language centers are mainly in the left hemisphere of the brain. In particular, language was thought to be dependent on grey matter, the part of the brain that contains mostly cell bodies and is responsible for information processing, as opposed to white matter, which contains mainly long-range connection tracts (axons) and is responsible for information communication. Researchers realized this understanding was an oversimplification when surgeons started to notice that cutting white matter tracts alone significantly impaired linguistic abilities. New methods, such as electrical stimulation of the brain during surgeries in awake patients, led to the realization that the whole brain is involved in language.

White matter fiber tracts of a human brain visualized with a Tensor Imaging technique. The U-shaped fibers connect the two hemispheres. The finding that these tracts are essential for language revolutionized the field of neurolinguistics because language was previously thought to be localized to gray matter in the left hemisphere. Credit: Thomas Schultz via Wikimedia Commons

White matter fiber tracts visualized with a tensor imaging technique. Findings that the fibers connecting the two hemispheres are essential for language revolutionized the field of neurolinguistics.
(Photo: Thomas Schultz via Wikimedia Commons)

When theoretical linguists such as Andrews joined the conversation, they merged empirical data with theory to answer questions such as, is language learned or innate? Are there specific structures and localized circuits in the brain responsible for language? And are there critical periods where our brain is particularly sensitive to changes?

The picture is complicated by the fact that “most of the world population is bi or multilingual,” and “one could argue that in fact there are no monolinguals.” In our daily lives, we use different languages at school, at work and at home (Learn more about this hypothesis here). Andrews’ current work addresses these complexities by looking at changes in neural activity as individual speakers acquire Russian as a second or third language. Her latest book “Neuroscience and Multilingualism,” coming out at the end of the year from Cambridge University Press, is an exploration of the neuroscientific modeling of multilingualism.

The lecture was part of Brain Awareness Week, a global campaign to encourage public interest in the progress and benefits of brain research. Not to miss: Michele Diaz on “Language and the Aging Brain” on Thursday, 3/5 at 7:30pm, and Richard Mooney on “Music and the Brain” on Friday, 3/6 at 6 pm at Motorco Music Hall.

Inside the Monkey Brain

By Ashley Mooney

On February 12, 2014

In Animals, Behavior/Psychology, Field Research, Neuroscience

By Ashley Mooney

Both in the lab and on a tropical island, primate behaviors can shed light on social-decision making.

To fully understand the biology of social-decision making, Michael Platt, director of the Duke Institute for Brain Science, conducts lab work at Duke and field research an island off the coast of Puerto Rico called Cayo Santiago. His research focuses on understanding both the physiological and social aspects of decision making.

“Our brains are exquisitely tuned to making [social] decisions and acquiring the information to inform them,” Platt said. “When these processes go awry, as occurs in disorders like autism, schizophrenia or anxiety disorders, the consequences can be devastating.”

Courtesy of Lauren Brent.

Platt’s group uses rhesus macaques as model animals because of their strong behavioral, physiological and neurobiological similarity to humans. But understanding how the monkey brain—and thus the human brain—works requires both laboratory-based biological information and social studies in a natural environment.

Researchers can combine the knowledge they gain from lab and field studies to create a holistic picture of the biological basis of behavior, said Lauren Brent, associate research fellow at the University of Exeter who did her post-doc with Platt at Duke.

Lab studies are best suited for quantitative, repeatable studies in which variables can be precisely controlled, Platt said. On the other hand, field studies emphasize external validity and an animal’s response in its natural conditions, but are not suitable for determining precise measurements of internal processes.

In the lab, Platt’s group studies the neural mechanisms that mediate prosocial and antisocial decisions, Platt said. They can also study the ways in which humans can enhance prosocial decisions using pharmacological or behavioral interventions.

On Cayo, the researchers are exploring the genetic factors that shape individual differences in social behavior and decision-making in free-living monkeys. They use observations, behavioral experiments and blood and fecal samples to study the monkeys non-invasively.

“The project on Cayo and the work that goes on the lab are complementary in the best sense because we can do things on Cayo that we can’t do in the lab,” Brent said. “For example, we have hundreds of monkeys, of known pedigree, interacting with each other in a purely spontaneous and naturalistic fashion. You can’t get that in a lab.”

Lauren Brent conducting behavioral observations on Cayo. Courtesy of Lauren Brent.

Although working with free-ranging monkeys can produce more naturalistic results, Brent noted that there are drawbacks to working in the field.

“Working with monkeys in the field is painstaking,” Brent said. “You need to be physically fit, but moreover it is a mentally demanding thing to do because you need to pay close attention to everything that is going on in the group at all times so that the data are as finely detailed and accurate as possible.”

Brent found that a monkey’s position in its social network is heritable and can impact the survival of its infants. She determined a monkey’s social connections using grooming and spatial proximity, or how long one monkey spends sitting next to other monkeys.

“Regardless of how big your family is, monkeys who are better connected in the grooming network have greater reproductive success,” Brent said. “Together, these results suggest that social interactions have adaptive benefits and are something on which selection has acted.”

Why Cute Babies are a Cognitive Illusion

By sa160@duke.edu

On February 11, 2014

In Behavior/Psychology, Lecture, Neuroscience

By Nonie Arora

Daniel Dennett, Co-Director Center for Cognitive Studies at Tufts University, spoke last week to a packed room at Duke University’s annual Mind, Brain, and Behavior lecture. He said that The Hard Problem of Consciousness, which describes how we have subjective conscious experiences, rests on a series of straightforward mistakes.

“The Hard Problem is a cognitive illusion,” Dennett said.

Cartesian Theater. Credit: Wikimedia Commons

Dennett’s conclusion rests on two tenets: (1) there is no Cartesian theater and (2) there is no second transduction. The Cartesian theater is an image of a place where the show happens; Dennett said it is where the decisions get made, according to some philosophers.

The second transduction is the idea that the nervous system first converts outer stimuli to neural signals and then the brain translates these signals to some other medium of consciousness, as originally suggested by Descartes. Some theorists still believe that there is a second transduction into a physical medium in the brain that has not been identified, but according to Dennett’s book Kinds of Minds, this idea is a myth.

Dennett said that the features in our brain are more similar to DVDs than to cinema films. They are not iconic. If you show a caveman a DVD, what will he think? He’ll think: where are the mini pictures, where is the sound? Anybody who thinks that there is a Hard Problem is making the analogous naive error about consciousness, Dennett explained.

Depiction of consciousness. Credit: New Yorker 1969 Saul Steinberg

We are the “unwitting creators of fiction,” he said. “Babies are not inherently cute. They’re cute because we adore them. Shapes of babies faces stimulate nurturing behavior… This is an evolved adaptation. We misinterpret an inner reaction as an outer cause,” he said.

He believes that we project our innate predispositions into the manifest world. Thus, we have a propensity to think that babies are cute. “We have expectations about our expectations,” he said. “Not only do we feel the urge to reach out and cuddle, we expect to feel that urge. Our satisfaction of that expectation confirms our perception of cuteness of the baby.”

Interested in hearing more from Dennett?

Learn more about the illusion of consciousness or why babies aren’t actually cute.

New Blogger: Olivia Zhu

By Olivia Zhu

On January 15, 2014

In Neuroscience, Physics, Science Communication & Education, Students

Hi! My name is Olivia Zhu, and I am a sophomore biophysics major hailing from Pleasanton, California. I’m thrilled to start writing for the Duke Research Blog.

When I started my Duke career, I had absolutely no idea what research was. I had a vague conception of it as a drawn-out, painstaking process in which one traded in his life’s freedom for a micropipette. However, midway through my freshman year, a conversation with Professor Henry Greenside prompted me to reconsider. Professor Greenside inverted my perspective on research: he showed me that research did not revolve around tedious procedures, but rather around the pursuit of answers to fascinating questions. Since then, all sorts of research topics, particularly those with some aspect of physics, have captivated me. I found that research fulfills the idealistic conception I have always held of education: research represents the ultimate pursuit of pure knowledge, often without the pressures of immediate practical application.

Currently, I work in the Mooney Lab of neurobiology, which studies the learning processes in songbirds. Via surgical viral infection, I am examining the role that dopamine plays in this circuit.

In other matters, I enjoy forsaking my science-based identity by taking English, art, and history classes. I play soccer, run around campus, read classic novels, and discuss philosophy with friends. At Duke, I am a part of the Round Table and pWILD communities. Sometimes I miss hiking in California or exploring the islands in Beaufort, North Carolina, but I know there’s no place I’d rather be than here in Durham.

I’m looking forward to sharing my exploration of research at Duke!

Fish Need Hugs Too!

By Karl Bates

On December 18, 2013

In Animals, Behavior/Psychology, Guest Post, Neuroscience

Guest post by Lauren Burianek, Doctoral Candidate in Cell Biology

In humans, massages are used for stress relief and relaxation. Tight wraps called Thundershirts can be used on dogs to reduce anxiety from thunderstorms or separation, and giant rolling brush machines are used in the milk industry to calm and comfort dairy cows. Physical touch can have some beneficial roles, but who knew that fish respond to touch, too?

Researchers at the Duke-NUS Graduate School in Singapore studied the effects of physical sensations on fear behaviors in zebrafish.

The zebrafish Danio rerio, workhorse of the lab, is the sensitive type. (public domain photo from Wikimedia Commons)

Zebrafish become afraid when they smell pheromones released by injured fish, and they respond by freezing in place, darting around quickly, or sinking. Why do the fish respond this way? Researcher Annett Schirmer explains, “species develop a sensitivity to these chemicals throughout the course of evolution such that these chemicals can trigger an automatic response, such as fear.”

In other words, by becoming afraid when a nearby fish is injured, the fish can escape or hide from predators more quickly, leading to an increased chance of survival.

Schirmer said that as a kid, her father would claim that his fish enjoyed being petted. “I never believed him,” she said. Instead of petting the fish, however, the scientists used moving water as a non-social physical touch. They wanted to see if physical touch could reduce fear responses in fish, similar to how physical touch can comfort humans and other animals.

[youtube http://www.youtube.com/watch?v=Hxzl54tUi2U?rel=0]

The zebrafish were exposed to the fear-inducing pheromone and then were either placed in a tank with still water or a tank with a water current for two minutes. The fish exposed to the water current showed fewer fear behaviors and lower levels of cortisol, a stress hormone, than the fish that were placed in the non-moving water. It seemed that the moving water helped to calm and reduce anxiety in the fish.

Fish have a sense of touch for feeling movement and changes in water pressure that comes from cells along the sides of their body called lateral line cells. When fish with damaged lateral line cells were put through the same study, the fish exposed to the water current did not show as large of a decrease in fear behaviors, suggesting that they really are responding to physical sensations from their sense of touch.

Fish swimming in schools feel movement from nearby fish and the current of the water as they are swimming through it. These sensations may reduce fear responses in a similar manner. Schirmer adds, “Current stirs up water and brings nutrients and oxygen. So I think that in the water, touch is a rich emotional stimulus that is, to some degree, also socially relevant.”

CITATION: Tactile Stimulation Reduces Fear in Fish, Annett Schirmer, Suresh Jesuthasan, and Ajay S. Mathuru. Frontiers in Behavioral Neuroscience. Online Nov. 22, 2013. doi: 10.3389/fnbeh.2013.00167

5 Dukies On List of World’s Top Biomedical Scientists

By Erin Weeks

On November 8, 2013

In Biomedical Engineering, Cardiology, Faculty, Medicine, Neuroscience

A recent paper in the European Journal of Clinical Investigation identified 400 of the world’s most influential researchers in biomedicine—and five hail from Duke University. The authors used citation data spanning 15 years (1996-2011) from Scopus, a database of peer-reviewed literature, to pinpoint researchers with high degrees of productivity and impact. Get to know the Duke researchers:

Robert M. Califf is a global leader in treating cardiovascular disease and has a long history at Duke, where he completed both his undergraduate degree and his MD. Califf serves as vice chancellor for clinical and translational research and directs the Duke Translational Medicine Institute. You can read Dr. Califf’s blog here.

Marc G. Caron is the James B. Duke Professor of Cell Biology in the School of Medicine, as well as a member of the Duke Institute for Brain Sciences. He studies how neurotransmitters, chemical messengers like dopamine and serotonin, regulate behavior and play a role in diseases like schizophrenia and depression.

Robert J. Lefkowitz was awarded the 2012 Nobel Prize in Chemistry for his work discovering and describing a large family of proteins, known as the G-protein coupled receptors, that regulate cellular responses to outside molecules. His work underlies a third to a half of all prescription drugs today. Lefkowitz is a professor of biochemistry, chemistry, medicine, and pathology at Duke.

Terrie E. Moffitt is a psychologist and the director of two longitudinal studies—one of 1000 New Zealand families and one of over 1000 British families with twins, which she uses to investigate how antisocial and criminal behaviors arise in individuals. She is the Nannerl O. Keohane university professor of psychology and neuroscience at Duke.

Eric D. Peterson is a cardiologist specializing in acute coronary systems and geriatric cardiology with nearly 700 peer-reviewed biomedical papers to his credit. He is the director of the Duke Clinical Research Institute and a professor of medicine at Duke University Medical Center.

Basic Science Day Should be Every Day

By Karl Bates

On October 15, 2013

In Cancer, Medicine, Neuroscience

By Karl Leif Bates

The Med School’s fourth celebration of basic science was held in and around the Great Hall of the gorgeous new Mary Duke Biddle Trent Semans Center on Monday, Oct. 14. Basic science hero and Nobel laureate Bob Lefkowitz of biochemistry packed the room for his keynote, “A funny thing happened on the way to Stockholm,” and attendance was steady throughout the day for a series of half-hour talks by Duke faculty from the six basic science departments of the Med School.

Immunology professor Yuan Zhuang closed his Basic Science Day talk on the lineage of T-Cells from infancy to adulthood with a powerful metaphor.

Immunology professor Yuan Zhuang closed his Basic Science Day talk on the lineage of T-Cells from infancy to adulthood with a very timely political metaphor.

“Duke’s scientists are invited to speak all over the world, but they often don’t have the chance to hear about the great science going on in the labs of their own colleagues here at Duke,” said Sally Kornbluth, vice dean for basic science and master of ceremonies for the day.

Anne West of neurobiology said “there’s still a gigantic gulf,” between what she’s investigating and patient care as she seeks to understand gene expression patterns in the brain that might leave one person more susceptible to high stress responses than another. “We’d like to be able to guess who’s going to respond adaptively and who’s going to respond maladaptively,” she said as she updated colleagues on her group’s progress.

But everything doctors can do for you in the clinic had to start somewhere. “New disease treatments don’t spring from nowhere,” said Kornbluth, who’s home department is pharmacology and cancer biology. “To advance clinical treatments, you need fundamental basic science to provide a pipeline of translatable discoveries. We saw several examples of this kind of work today, from Mariano Garcia-Blanco working on ways to eradicate Dengue and Yellow Fever viruses, to Donald McDonnell establishing important links between obesity and cancer via cholesterol metabolism.”

Speaking of progress, three dozen posters out in the lobby offered updates on Duke’s basic understanding of breast cancer and brain cancer; salmonella, chlamydia and fungal pathogens; DNA repair, RNA interference, neuronal circuitry and Alzheimer’s, schizophrenia and obsessive-compulsive disorder.

Duke Experts Ponder "Brains on Trial"

By Clara Colombatto

On September 13, 2013

In Behavior/Psychology, Faculty, Neuroscience

Guest Post by Clara Colombatto T’15

Neuroscience research is finding its way into the legal system in an increasing number of cases. A panel of four Duke Professors explored the gap between laboratory and courtroom and its consequences on the attribution of guilt and responsibility in a Sept. 11 discussion at the Nasher Museum that was taped for broadcast on PBS-TV the next night.

“Every time we introduce new science into the courtroom, there’s an overconfidence by jurors in the science, as if that’s the objective truth,” said panelist Nita Farahany, Professor of Law, Genome Sciences and Policy, and Philosophy. But when transferring experimental evidence to real-life situations there are many caveats.

The panel discussion taping in the Nasher Museum Auditorium. Host Alan Alda is at right. (Megan Morr, Duke Photography)

Farahany played a significant role in the two-hour series “Brains on Trial,” a PBS special that explores the role and implications of recent advances in neuroscience in criminal justice. The show is hosted by Alan Alda, six-time Golden Globe winner and science journalist, who also moderated Wednesday’s discussion.

In addition to Farahany, the panelists were Ahmad Hariri, Professor of Psychology and Neuroscience and Investigator at the Institute for Genome Sciences and Policy, Scott Huettel, the Jerry G. and Patricia Crawford Hubbard Professor of Psychology and Neuroscience and Director of the Center for Interdisciplinary Decision Sciences, and Walter Sinnott-Armstrong, the Chauncey Stillman Professor in Practical Ethics in the Philosophy Department and the Kenan Institute for Ethics.

The Duke experts said neuroscientific evidence is starting to show the potential to determine, for example, if a witness is lying, if a juror is racially biased, if a brain disease impedes voluntary action, or if executive control regions are not yet developed in a juvenile defendant.

Some discoveries might save lives: Kent Kiehl, a professor of psychology, neuroscience and law at the University of New Mexico who has worked with Sinott-Armstrong, found that lower activity in the anterior cingulate predicts repeat offenses in psychopaths.

Hariri said his work is adding a piece to the puzzle by finding out how gene expression maps onto these brain pathways.

However, Scott Huettel points out that mistakes might arise from inaccurate generalization of function and anatomy that are unique to each individual, or from incorrect interpretation of a pattern of activation.

Hariri also warns about the risks of transferring results from an artificial laboratory setting to a real life situation which is subject to the forces of emotions and intentions.

Philosopher Sinnott-Armstrong raises ethical issues: brain imaging may violate privacy, and threaten our fundamental belief that we are in control of our thoughts, especially when those thoughts might be self-incriminating.

So the transfer of scientific evidence and legal cases is a sophisticated problem. While research advances, as Sinnott-Armstrong notes, “the court has to figure out the right procedure to minimize dangers while still extracting as much information as possible.”