My Lab

This week I am preparing to defend my thesis proposal, so I thought I’d share a write-up of my lab in the New York Times:  http://www.nytimes.com/2012/01/13/us/robotic-technology-to-help-understand-and-treat-strokes.html

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Seeing the light

Imagine being in your early thirties, married and excited about what life has in store for you.  One day, you start to notice that your peripheral vision is not as good as it once was.  You have a hard time detecting things that are not right in front of you; objects and people start to appear very blurry; reading and driving become impossible.  After consulting your doctor about this problem, you are told that you have a genetic condition called retinitis pigmentosa.  There is nothing that can be done, and eventually you will lose your sight completely.  You will just have to adjust to this new way of life.

In the eye, the cells that convert light signals from the external world into neural signals are called photoreceptors (the rod and cone cells in the diagram below).  They sit at the back of the eye and detect light as it hits the retina.  Once they detect this light, they have to translate it into a language the brain can understand, crucial for transmitting visual information to the brain.  Retinitis pigmentosa causes degeneration of these rod and cone cells, and therefore leads to the breakdown of the interface between the world (light) and the brain.  Without these cells, information about a visual scene becomes stuck and unable to get through to the brain to be processed; the brain cannot interpret visual information, eventually leading to blindness.

picture of the retina

(Jamie Simon, Salk Institute for Biological Studies)

 Larry Hester was diagnosed with retinitis pigmentosa more than 30 years ago, but recently, he was able to see light again for the first time in many years.  Researchers at Duke University implanted a device with many tiny electrodes that could essentially bypass the damaged rods and cones to send information to the brain.  Here is how it works: Larry wears glasses with a video camera attached, which sends a signal about what Larry is looking at through a tiny wire to a computer attached to his belt.  The computer receives the information and relays it to the electrodes on the retina, which activates the cells that project into the brain.  The device is translating the light information into neural activity, giving Larry the ability to experience and interpret the image he is looking at.  At a basic level, the device is able to perform the function of the photoreceptors that have died.

See Larry’s amazing experience here: http://www.wimp.com/bioniceye/

It is important to note that this technology is new and limited, giving Larry only a blurry version of the world.  Despite this, I have no doubt that the technology and its use will continue to improve rapidly, inching closer and closer to giving people normal vision.  Larry says it is his dream to be able to see his wife’s blue eyes again.  Although he is not able to achieve this with his current implant, at least he is one step closer.

Dr. Paul Hahn, an Assistant Professor at the Duke Eye Center, points out that we are entering an era of medicine where, for the first time, instead of just watching as patients lose basic abilities such as vision or movement, we can start to build devices that will help restore those abilities.  What an exciting new time!

It is often the case that researchers can get discouraged by costly failures and uncertain obstacles, but this is the important work that serves as a necessary reminder that every once in a while, when things work out, it is actually possible to give someone back the gift of sight.

Citations:

Price, Jay. “Duke Fits First Patient in State History with ‘bionic Eye'”Newsobserver. N.p., 10 Sept. 2014. Web. 19 Oct. 2014.

http://www.newsobserver.com/2014/09/10/4140145/duke-fits-first-patient-in-state.html

“It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better.  The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood; who strives valiantly…who knows great enthusiasms, the great devotions; who spends himself in a worthy cause; who at the best knows in the end the triumph of high achievement, and who at the worst, if he fails, at least fails while daring greatly, so that his place shall never be with those cold and timid souls who neither know victory or defeat.”  Theodore Roosevelt, “The Man in the Arena,” 1910.

Stereotype This

On a crisp fall evening of November last year, a young woman was heading home after a night out with friends.  In the early hours of the morning, she reportedly sped down the street and hit a parked car.  Confused and discombobulated, she wandered to a nearby house in search of help, and after banging on the door, she watched as it opened to a man behind the screen.  He was standing there with his shotgun raised towards her.  Before she could say anything, he shot her in the face.

The facts of this story make it particularly shocking and horrific, but it is made more complicated by the fact that Renisha McBride was African American and her killer, Theodore Wafer is white.

Some scholars have argued that racial bias has declined due to strengthening of egalitarian social norms, but anyone who tries to argue that racism is a thing of the past is not seeing the full picture.  It is a complex and deeply ingrained problem in our society today that has been made all the more clear for me since moving to Chicago.  I hear it in the personal story of a friend who was faced with the question “do you belong here?” in the elevator of his own building; I see it in reports of the persistent tragedy of gun violence in South Side Chicago; I read it in the news cycles about Trayvon Martin and Michael Brown; story after story demonstrating hatred and prejudice, on all sides.

We live in a world in which displaying outward prejudice towards others is no longer socially acceptable.  We know it’s not ok, and most people try to behave in ways that do not imply obvious prejudicial feelings.  We think we know ourselves and how we will react in a given situation, but what if our brains hold beliefs that we are not consciously aware of?  And if this is the case, how could we even detect these hidden beliefs?

We can turn to neuroscience for answers.  

Modern neuroscience has the ability to probe the nervous system in ways that go beyond our reported and conscious experience.  It can detect processes that are going on underneath the surface, and doing so might help us better understand why people who sincerely believe they are not racist might still make racist decisions in the heat of the moment.

Let’s start at the beginning: looking at a face.

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Our eyes pick up information about how that face reflects light.  You might think that once this information reaches the eye, it gets sent into the brain to be processed and interpreted.  While this is partially true, the story is a little more complicated.

Face Area in the brain

There is an area in the brain that is specialized for interpreting faces.  When the wolf sees the attractive lady face, his own face area activates (the orange blob in the back of the brain, above the ear).

PIIS0140673609613763.gr2.lrg

Research has shown that this area activates more in response to members of one’s own racial group (your ingroup) when compared to other racial groups (your outgroup).  As early as 170 milliseconds after seeing a face,  this difference shows up in electrical activity coming from this face area.  The solid line (in the figure below) reaches a lower point, representing an increased response to people within an individual’s group.

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This evidence suggests that at the very earliest stages in processing a face (.17 seconds after!), information about social group membership may be influencing our response at an unconscious level; therefore, visual perception is not just a direct sequential export of information from the eyes to the brain, but instead a complicated mixture of the perceived subject and a whole lifetime of previous experience and cultural exposure.  It would be like having an unusual camera; instead of taking an objective picture representing items in the world, it would produce a doctored image that put some parts of the image in focus and make others blurry based on previous pictures taken.

The Amygdala

We also see racial differences emerge in a small structure in the brain called the amygdala, an almond shaped cluster of cells that are thought to be involved in memory, decision-making and emotional reactions.

amygdala

Jaclyn Ronquillo and her colleagues carried out a study where they flashed photos of faces to participants and measured brain activity.  The faces were either light or dark versions of white or black individuals (see examples below).  They found that darker skin tones elicited a greater amygdala response (“white dark”, “black light”, and “black dark” bar graphs labeled below), which they explained as a heightened fear response.  Unexpectedly, this trend also shows up in African-American subjects viewing darker skin tones, suggesting that the amygdala may be responding to cultural exposure rather than just ingroup/outgroup categories.

F1.medium F3.medium

These two brain regions, the face area and the amygdala, seem to be responding to slightly different things.  The face area activity is related to familiarity with the face (have you seen this face before?); the amygdala response seems to be more of a learned fear response based on previous experience with the world.  These research studies reveal some potential sources of the bias that is able to hide in the depths of the brain.

If these biases exist, how are we able to appear unbiased?

Humans must constantly navigate a social world, and they need to play by the rules of the culture to be accepted.  People must try to curb any unwanted influences of implicit stereotypes, an action that seems to involve a brain region that detects internal conflict: the anterior cingulate cortex (ACC).  Activity in this part of the brain has been associated with a person’s motivation to respond without prejudice.  During times of internal conflict, the ACC will activate, helping to hide our bias not just from the outside world, but also from ourselves!

So we are left with a battle in the brain.

A brain faced with overt questioning regarding race may have the cognitive control to produce the socially acceptable answer (through ACC involvement); however, processes that bypass conscious awareness and produce implicit bias may still be able to influence behavior when decisions are not carefully evaluated.

How does this help us understand what happened to Renisha McBride?

Is it possible that Theodore Wafer, stumbling to his door in the middle of the night, committed this terrible atrocity because of the signals coming from his face area or amygdala?  Could this have been prevented if his ACC had kicked in to regulate his behavior?

People are convinced that they excel at seeing things objectively and without bias, but stories like this one and neuroscientific data tell us otherwise.  The brain is constantly filling in the blanks with past experience, making shortcuts that help us sift through infinite amounts of information every day.  Gaining a deeper understanding of the biological basis of racism can better arm us against allowing it to influence the decisions we make every day.

What can we do when these shortcuts do more harm than good?    

The first step comes from being aware that implicit bias exists, and it is able to influence behavior in ways we may not be aware of.  Knowing that our nervous system may be working behind the scenes in ways we don’t directly experience is the first line of defense.

Research also suggests that we can change these supposed automatic responses by developing a different framework and redefining the boundaries of the ingroup.  The automatic bias response is eliminated when the definition of a group is shifted.  This could be a shift from focusing on racial boundaries to focusing on members of one’s own sports team.  When an individual sees a face as a fellow teammate rather than a member of a different racial group, she no longer displays a different response to racial groups that are not her own.

In this country, prejudice against African Americans is one clear example of ingroup/outgroup mentality, but this concept can be applied to any of the many conflicts seen around the world.  Whether it is a line drawn regarding race, religion, or gender, all the overarching concepts stay the same.

This is a complicated issue that is deeply ingrained in history, culture and politics, but I truly believe that understanding the role the brain plays in social prejudice and stereotyping is a crucial step towards decreasing and ultimately eliminating them.

Sure, but how is this relevant to me?

Not many people will be faced with a stranger on their porch in the middle of the night or required to make a snap judgement while holding a gun; however, these principles are highly relevant in any kind of workplace environment as well.  Check out this great video that google produced about implicit bias.

We need to take responsibility for understanding what assumptions we make on a day to day basis, and shift the way we view others.  Ask yourself, who is in my group and could these lines be changed?  Can a group simply be fellow city-dwellers, leaving race out of it?  What would the world look like if everyone became more aware of the biases they have?

I’d love to hear your thoughts on this!

Citations:

Lieberman, M.D., et al., An fMRI investigation of race-related amygdala activity in African-American and Caucasian-American individuals. Nat Neurosci, 2005. 8(6): p. 720-2.

Ratner KG, Amodio DM (2013) Seeing “us vs. them”: Minimal group effects on the neural encoding of faces. J Exp Soc Psychol 49: 298–301. doi: 10.1016/j.jesp.2012.10.017

Ronquillo, J., Denson, T.F., Lickel, B., Lu, Z., Nandy, A., & Maddox, K.B. (2007). The effects of skin tone on race-related amygdala activity: An fMRI investigation. Social Cognitive and Affective Neuroscience, 2, 39-44.