The (not so very) fearless amygdala

          There are certainly some emotional responses that I would rather do without. You have mostly likely encountered at some point the well-used horror movie scene in which the protagonist, cautiously tiptoeing down a dimly lit hallway, approaches a corner or doorway and suddenly…bam! Out leaps the villain/axe-murderer/monster, and you jump, feel your heart rate kick up a notch, and involuntarily grab whoever is sitting next to you in the theater. Or the situation in which you must venture into a dark basement or attic and find yourself sprinting back to the main floor, heart pounding, at a strange noise or the perceived movement of a shadow.

As useful as this stress response may be when danger is actually present, it is less appropriate in the usual safety of most basements and movie theaters. Nonetheless, even if you know that nothing good can happen at the end of that dark hallway on screen, the sympathetic branch of your body’s autonomic nervous system still presents a classic response. What enables you to feel that fear? Furthermore, what if that reflex were muted or lost?

Fortunately for science, there’s a rare, autosomal recessive genetic disorder to give insight into that question. Urbach-Wiethe disease, also called lipid proteinosis, is a gradual thickening and hardening of the body’s mucous membranes. The symptoms of the disorder are caused by the infiltration of the skin, brain, and mucous membranes by a substance similar to hyalin, a large, acidic, strongly adhesive protein that plays an important role in embryonic development. Symptoms include waxy papules on the face and around the eyelids from a buildup of hyaline material, vocal hoarseness, thickening of the tongue and impaired ability to heal from wounds. While generally not fatal, lipid proteinosis can become dangerous when it affects the respiratory system or brain. With respect to the respiratory system, enlargement of the tongue or hyaline deposits in the pharynx can obstruct breathing. With respect to the brain, the hardening of tissue in the medial temporal lobes can cause epilepsy and other neurological disorders.

One of the structures often damaged by the calcification caused by Urbach-Wiethe disease is of particular interest to neuroscience: the amygdalae. These two small, almond-shaped collections of nuclei are located deep within the brain’s temporal lobes and perform a variety of intriguing functions. Most notably in this case, they play a role in emotional memory, which brings us back to our opening horror movie scene. Lipid proteinosis patients with damaged amygdalae can have trouble identifying and relating to fear. One patient with almost completely destroyed amygdalae, known by her initials SM, seems fearless indeed. Haunted houses, disturbing movie footage, and even experiences such as being held at knifepoint induce in her not the slightest hint of panic or urgency. According to three scientists at the University of Iowa who have worked with her extensively, SM cannot tell what a fearful facial expression looks like or means, nor can she draw a fearful expression when asked, though she has no trouble identifying and illustrating other emotions.

Though cases of Urbach-Wiethe disease do not imply that the amygdala is the fear center of the brain, they do highlight its role in fear processing, likely as a stop that connects areas of the brain that sense the environment to parts of the brainstem that initiate fear and stress responses. While much remains to be studied about the enigmatic roles of the amygdala, in the meantime, you know what little almond-shaped structures play a big part in the next time you jump out of your skin in a movie theater.

-Kate Oksas

Sources

<http://blogs.discovermagazine.com/notrocketscience/2010/12/16/meet-the-woman-without-fear/#.VH-MjTHF9qI>.

<http://brain.oxfordjournals.org/content/126/12/2627>.

<http://www.sciencedirect.com/science/article/pii/S187140480500002X>.

Memory Palaces & Avoiding Ancient Greek Dinner Parties

One night around 514 B.C., the Greek poet Simonides of Ceos was attending a dinner party. According to myth, it ended rather badly. The banquet hall buckled and collapsed, crushing everyone inside beyond recognition—except Simonides, who had stepped outside and was saved. (Okay, it ended very badly.) As the story goes, although the dead were too crushed to be identified by their physical features, Simonides was able to name each one by recalling where the unfortunate partygoers had been seated, and from the disastrous feast came an interesting mnemonic technique called the method of loci.

Simonides was apparently struck by the idea that one could remember anything by associating it with a mental image of a location. This method, also known as a memory palace or mind palace, links memories with specific spatial locations and activates brain regions such as the medial parietal cortex, the retrosplenial cortex and the hippocampus, which are all involved in spatial awareness.

The place a person chooses as a memory palace should be complex as well as well-known, for instance, his or her house. The important aspect of the technique is not the actual space chosen, but rather the visualization and the interaction of each part of a visualized memory with the surroundings. If, for example, a person were trying to remember a shopping list that included toothpaste, he might picture himself walking into the bathroom and squeezing an enormous tube of toothpaste into the sink. Creative, vivid and absurd visualizations add to the effectiveness of the method, so fully imagining the smell of the toothpaste and the feeling of squeezing the tube would help solidify the item at that particular locus.

The success of the method comes from its use of trigger locations along a familiar route—or, for more advanced memorizers, a route designed entirely in one’s mind. The technique has been employed by real and fictional people ranging from Simonides to Sherlock Holmes to Hannibal Lecter to Gary Shang, who took it upon himself to memorize pi to over 65, 536 digits and who makes my mind palace look like a mind hovel.

Though it might seem like a lot of work just to avoid writing down a grocery list, I suppose you never know when you might end up in a structurally unsound banquet hall and have to show off your visualization skills. Happy remembering.

—Kate Oksas

Sources

<http://www.smithsonianmag.com/arts-culture/secrets-sherlocks-mind-palace-180949567/?no-ist>.

<http://health.howstuffworks.com/human-body/systems/nervous-system/how-to-improve-your-memory7.htm>.

<http://remembereverything.org/memory-palace-the-method-of-loci/>.

An Optical Illusion: What do you mean that’s not a spiral?

We all have our own set of burning questions—those inquiries that sit in the back of our minds and refuse to leave us alone. They vary widely from person to person; Alessandro Volta was apparently tormented by the mystery, “What would happen if I completed the circuit of a 50-volt battery by sticking two metal rods into my ears?” while Paul Broca wondered (somewhat more prudently), “What does the brain’s left frontal lobe have to do with our ability to speak?”

A question that bothers me on occasion (while perhaps not quite as creative as Volta’s) is one regarding optical illusions. Specifically, “Why does my brain tell me that the picture below is a spiral?”

The image consists of concentric circles (you can trace one with your finger for proof). I know that the image consists of concentric circles, but no matter how I try to convince myself of the fact, all I can see is a spiral. The illusion, known a Fraser spiral or a false spiral, was first studied by British psychologist James Fraser in 1908. It combines a regular pattern of circles with misaligned, differently colored strands, which create visual distortion. And as if the tilted strands weren’t hard enough on our unsuspecting brains, the checkered background also contains spiral components to heighten the illusion.

The deception happens through a combination of simple image processing in the retina and more complex processing in the brain’s striate cortex, a primary visual receptive area. Orientation-sensitive cells in the cortex make horizontal connections with each other that change depending on context. In the case of this irritating not-spiral, the cells interpret the message of diagonal bands—that is, the misaligned black and white strands—that they receive from the retina as an unbroken line, creating the appearance of a spiral.

Maybe not the most dramatic answer, but at least it didn’t require closing an electrical circuit with my ears.

-Kate Oksas 

Sources

<http://www.psychologie.tu-dresden.de/

i1/kaw/diverses%20Material/www.illusionworks.com/html/fraser_spiral.html>.

<http://mathworld.wolfram.com/FrasersSpiral>.

Brainstorm Enters the 21st Century

Like learning about the brain? Wish you could learn more? We've got you covered! The Brainstorm team is excited to announce the first ever Brainstorm twitter account! Follow @PennBrainstorm for daily facts on all things neuroscience!

To Be Another

I was hopping around the Internet, when a certain headline jumped out at me: “What’s it like to see through the eyes of Another?” This was either going to be about some bizarre alien conspiracy or some very enticing science experiment. What I found was a project called “The Machine to be Another”, which was conducted by a Barcelona design collective. A team of artists, programmers, and engineers sought to experiment with empathy, perspective, and reality.

Typically in labs that explore empathy, subjects use computer avatars and answer questions while sitting in front of a screen. Video games are a common tool of simulation to study racial or gender bias. In the Be Another lab, however, there is a new method to create integrative approaches to expand our concept of reality.

Using two large goggle and earpieces mounted on the two subjects’ heads, the user’s brain is essentially tricked into seeing a 3-D, lifelike video of the other person’s perspective. The goggles record the view from one user and then feed those images and sounds to the headset of the partner. When the two subject sync their movements—by touching objects, looking around the room, and feeling their respective bodes—the subject gets the complete sensation of being in the other’s body.

The goggles were designed based off of the Oculus VR, which is a virtual reality headset originally designed for immersive video gaming. The headset uses tracking technology that allows for 360 degree viewing. Every movement that the goggles pick up gets tracked in real time, which allows for optimal viewing. The Oculus rift captures unique and parallel images for both eyes, which is similar to the way our eyes view the world. The headset mimics reality as closely as possible.

Here’s the scene: a man and woman stand opposite each other. They are both naked save for a headset that is connected to a monitor for third-party viewing. The woman will look at her hands and see hairy knuckles and a bulge in her pants. The man is quick to explore his newfound breasts. As long as the pair stays roughly in sync, the Machine To Be Another can cheat the brain and convince people that they have switched bodies.

This sounds like some sort of sci-fi version of 13 going on 30, but the Be Another Lab is focused on studying issue of race, gender, and physical disability. The most startling aspect of the experiment of the lab is how quickly the brain changes its understanding of reality. After years and years of living in the same body, in fewer than ten seconds your can brain forget your old physique and accept a completely new reality. That’s pretty cool. A relatively low budget art science experiment can make brains forget sex, physical build, and the sound of your own voice.

The brain displays astounding plasticity in its ability to pick up new languages, patterns, and ideas, but this seems to strike another level of impressive. The brain is so able to blur the boundaries between self and other. What has been such a foundational human belief—that we are ourselves and everyone else is someone else—is being put to trial by this type of experimentation. Indeed we are developing new tools to study human sympathy that can affect human sympathy.

Perhaps with gizmos like this becoming less experimental and more practical, we will be forced to accept the existence of other people on an entirely new level. We will be able to interact with someone else’s existence, either a stranger or a brother. The ultimate scope of this experiment is far from over. Technologies like this will continue to proliferate, and as they grow, our minds will need to expand with them.

By: David Ney 

Insights from the Perspective of an Undergraduate Researcher

I recently completed my first semester of independent research. As a Biological Basis of Behavior major at Penn, I have the opportunity to work in a lab for 10-12 hours per week and earn credit. I currently work in Dr. Anjan Chatterjee’s lab, the details of which I will elaborate on in a separate post. I started working in the lab last July and plan on continuing the project during this upcoming semester.

Now that the semester is over, I have unsurprisingly been reflecting upon the things I learned. I’ve realized that I had many misconceptions about what “research” entails. I’m still not quite sure where my previous views of research originated from…maybe high school biology and chemistry labs or inaccurate stock photos in textbooks. Regardless, I hope to dispel some of these ideas which I know, after speaking to other undergrads, are not unique to myself.

Here are some of the things that surprised me the most.

1) Research takes a really, really, really long time.

When I started in July, I was expecting to have completed an entire project and sent out a paper to be published by the end of the semester. Long story short, I was wrong. Getting enough subjects was one of the initial hurdles. The practical challenges of finding people who met the criteria just hadn’t occurred to me. I learned the hard way that not everyone wants to come to the lab to participate in our study, even if they already signed up to do so. I was also overwhelmed by the sheer amount of data we collected. Each subject yielded a 30,000 line spread sheet with over 12 columns of numbers. With over 55 subjects, it took (and is still taking) awhile to format everything so that it can be analyzed using a statistical program. I’ve read many studies in the past, but I now have a better understanding of the sheer amount of time and effort that went into each article. A succinct 5-page paper could easily take thousands of hours to produce. Researchers are probably some of the most patient people out there.

2) Labs are not all sterile places filled with test tubes and pipets.

Look what comes up when I type in “research lab” on Google: https://www.google.com/search?q=research+lab&safe=active&espv=210&es_sm=91&source=lnms&tbm=isch&sa=X&ei=4jTIUumNBsbNsQSAqIDgDQ&ved=0CAkQ_AUoAQ&biw=1223&bih=651. This makes me feel slightly better about the fact that this was exactly how I envisioned a “lab.” Microscopes. Rubber gloves. Colorful chemicals. Lab coats. I could not have been further from the truth. I guess I never really considered cognitive neuroscience labs when I was younger. My research professor’s office overlooks a beautiful pond and has walls covered in modern art. There is no “lab” per se. The researchers who work for Dr. Chatterjee have their own offices and cubicles scattered throughout the 3^rd floor of the Center for Cognitive Neuroscience. There are some patient testing rooms, but all of our eye tracking trials were run in a regular office at a desk. If I were to walk into the building and remove all the neuroscience posters on the walls, it would look more like a scene from corporate America than a prestigious scientific institution, aside from the fact that no one wears a suit.

3) Labs are actually social places.

This one goes along with my previous misconception. In that sterile place, I imagined people in lab coats and goggles pipetting things into test tubes for hours without any human contact. While there are a lot of opportunities for individual work, there is almost just as much collaboration. I did not do anything without first consulting with my two co-workers and discussing what the best course of action would be. In weekly lab meetings, everyone updates the group on their progress and any problems they faced during the previous week. We even had lab dinners which, while not centered around the research, definitely allowed me to get to know people better which helps the overall chemistry of the group in the long run. I know that it’s cheesy and that we’ve all been hearing this from a young age, but cooperation really does yield to better results.

Working in a lab was not what I expected it to be, but I had a great experience overall and look forward to continuing my research in the future. While the excessively long excel spreadsheets continue to haunt me, I genuinely believe all this work will be worth it if I am able to provide some new insights to the scientific community. On top of that, I’ve met some extremely interesting people to look up to as I continue my undergraduate studies. I’m excited to see what challenges and successes next semester will bring.