Scientific Chicago with Neil Shubin

Dinosaurs, Deception, Touch & Nanoparticles

Can lying be perfected? Researchers at Northwestern University delve into the art of deceit. The Field Museum looks at what caused dinosaurs to grow so large, and a potential breakthrough in the treatment of multiple sclerosis. Our science guy, Neil Shubin, joins us on Chicago Tonight at 7:00 pm with these stories and more in tonight's Scientific Chicago.

Plant-Eating Dinosaurs

The generally accepted theory around plant-eating dinosaurs was that bigger was better. Dinosaurs relied on fermentation in the gut to digest food; therefore a big belly was needed to do this. This seems to be the general trend in all kinds of creatures like elephants, brachiosaurs, and even whales.

Lindsay Zanno, research assistant professor of biology at North Carolina State University and director of the Paleontology & Geology Research Lab at the North Carolina Museum of Natural Sciences, and Peter Makovicky, associate curator of paleontology at the Field Museum in Chicago, decided to see if diet was driving size.

They looked at an evolutionary tree of plant-eating dinosaurs to determine if there was a trend toward increasing body size. What they discovered though is dinosaurs got both bigger and smaller. Essentially, eating habits didn’t necessarily dictate size in dinosaurs.

“Results of our study don't rule out diet as affecting body mass, but do seem to indicate that fluctuating environmental conditions over time were trumping the benefit of becoming a giant,” Zanno says. “The long and short of it is that for plant-eating theropods, bigger wasn't always better.”

So what does drive size? There are several theories including more oxygen in the atmosphere, biological environment and being large is more metabolically efficient.

“Where resources permitted, these animals could get as big as elephants, but that clearly was not the case in all environments and time periods," says Makovicky. “Factors such as resource abundance and competition with other herbivores likely played a more significant role.”

Image credit: David BethuneDeception Can Be Perfected

Northwestern University research shows that lying can be an art form: all it takes is some training and instruction. When people tell a lie, they tend to take longer and make more mistakes in their responses, compared to when they’re telling the truth, because with lying they have two conflicting answers in their mind.

Researchers set out to see whether lying can be trained to be more automatic with fewer errors.

In one group, participants were told to speed up their lies and to not make any mistakes, but they weren’t given time to prepare an answer ahead of questioning. A second group received the same training but was also given time to rehearse responses.

The group that was able to practice their lies had no difference between their deceptive and truthful responses.

“We found that lying is more malleable and can be changed upon intentional practice,” said Xiaoqing Hu, lead author of the study.

Researchers also found that just instruction alone reduced reaction times with participants’ deceptive responses.

In real life, there usually is a time delay between a crime and interrogation, so lie detector tests are often used, relying on physiological responses to detect deception. Next, researchers will be exploring whether or not additional instruction could train physiological changes in addition to behavior changes.

Image credit: David BenbennickSense of Touch ‘Uses Vibrations Just Like Hearing’

It turns out our sense of touch uses vibrations to send information to our brain about a particular object, just like vibrations convey information about sound for hearing.

And it’s the precise timing and frequency of the vibrations that really inform our sense of touch as to the objects and surfaces around us.

Researchers at the University of Chicago found that skin is highly responsive to vibrations, and that they produce corresponding vibrations in the nerves that carry information to our brain. This informs specifics like texture to our brain.

When the research team analyzed their data, they found that vibrations produce corresponding oscillations in our nerves, but even more intriguing was that they could predict how human subjects would perceive vibrations based on neural responses.

“In this paper, we showed that the timing of spikes evoked by naturalistic vibrations matters, not just for artificial stimuli in the lab,” said Sliman Bensmaia.

This means that with any given texture, we know what vibrations it will produce in the skin and nerve. For example, if we know the number of vibrations in skin and nerves when we touch silk, we could replicate this same feeling by stimulating the nerves with the same frequency of vibrations without ever touching the fabric.

This research could have an enormous impact for prosthetics and the amount of control and sensory information that they are able to send. Our sense of touch helps us determine how much pressure to put on things; for example, holding up a coffee mug. Using this technology in prosthetics would help people with artificial limbs have more fine control with objects.

Breakthrough Nanoparticle Could Help Treat Multiple Sclerosis

Northwestern Medicine researchers have discovered that a small nanoparticle could be the answer to treating immune-mediated diseases, like Multiple Sclerosis.

In MS, the immune system attacks the myelin sheath protecting nerve cells in the brain, spinal cord and optic nerve. When this insulation is damaged, nerves can’t convey signals as efficiently and it results in a range of problems, from limb numbness to paralysis or blindness.

Current treatment for MS suppresses the entire immune system to slow down the process of degradation, but this makes patients susceptible to infection. What researchers discovered is that they could attach myelin antigens to a nanoparticle that was then injected into mice.

The antigen faked the immune system into thinking that myelin was normal and it wouldn’t break it down. Instead of shutting down the immune system, the immune system is reset to normal.

“This is a highly significant breakthrough in translational immunotherapy,” said Stephen Miller, a corresponding author of the study and the Judy Gugenheim Research Professor of Microbiology-Immunology at Northwestern University Feinberg School of Medicine. “The beauty of this new technology is it can be used in many immune-related diseases. We simply change the antigen that's delivered.”

This method could also be used to treat Type 1 diabetes, food allergies and airway allergies like asthma. The nanoparticle is made of an FDA-approved substance and is now being tested in humans.