Where Does "Identity" Come From?

 (You, Your Brain, and the Nature vs. Nurture Debate)

Imagine your life is a tape, and we rewind it. All your accomplishments, awards, and graduations are erased. Your experiences move in reverse, and you grow smaller and smaller, as you were as a child. Your adult teeth turn back into baby teeth, and eventually retract completely, while all of your traits and quirks start to fade away. Pretty soon language goes away too, and you’re no longer you, but potential you. The tape continues rewinding, halving colonies of your cells until finally we arrive at the amazing singular miracle: the one cell that will evolve to become you.

Now, the question is this: what happens when we press “play” again? The common battle between nature versus nurture arises – the question that psychologists and scientists everywhere are prodding, probing, and researching to figure out. Are your talents, traits, and personal characteristics deeply embedded in your genes? Is what makes you you implanted in the DNA of our cells? Or could things completely change who we are with a few simple nudges? To put it simply – how much of your fate do you believe depends on your genes, your surroundings, or merely just by chance?

Since we can’t rewind time, Julia Freund and her colleagues found another way to better answer this question in a simple but remarkable recent study. To test the nature-versus-nurture phenomenon, Freund and her investigators placed genetically identical mice in a common environment, and tested to see whether systematic behavioral differences still could emerge. By answering “yes,” it would mean that there are sources of behavioral variability (intrinsic individuality, if you will) that could be unaccounted for by a combination of common genes and a common environment.

For the experiment, 40 genetically identical mice were placed in an “enriched” environment, where Freund monitored their behavior for a period of three months (which, for mice, is about 10-15% of their entire lifespan). The enriched environment was about 36 square feet, engineered to include multi-tiered platforms, nesting boxes, and interconnected tubes in order to promote exploratory behaviors in the mice that would not exist in a normal confined cage. What makes this study different from one of human twins is that by using mice, the subjects’ movements could be recorded with extraordinary detail over a major period of their lifespan. A radiofrequency ID transponder was placed on every mouse, measuring their every movement, chase, and sedentary period.

In order to measure the differences in behavior between the mice, the investigators used a gage called “roaming entropy.” Roaming entropy captures how often you get out, and with how much variety – so basically if you are someone who just darts back and forth (say from your dorm room to Van Pelt…) your roaming entropy is low. But if you’re the type of person who could pretty much be anywhere at any given time, you have a high roaming entropy. At the beginning of the study, the mice all had fairly similar roaming entropies… however, as the weeks progressed, the population diverged significantly, with some mice being much more exploratory and active than others. If you take the tendency to explore as a characteristic trait, then this is obviously one that elaborates and changes over time in a way that isn’t strictly determined by genes or the environment.

However, the most interesting part of the study arose when Fruend and her team examined the changes in brain activity that went along with the changes in exploratory behavior. Before the experiment was over, the mice were injected with a compound that selectively incorporates itself into dividing cells. This basically means that the compound can show researchers which neurons are formed in adulthood, and which neurons the mice were born with. While most of our neurons are formed during early development, there are a good number of well-studied brain areas that continuously produce new neurons throughout our adult lives.

Surprisingly, the mice that were the most exploratory throughout the study (who exhibited the most outgoing behavior) were also those who experienced the greatest production of adult-born neurons. While we can’t say this particularly proves anything, the results are still pretty intriguing. Even after your genes are set in stone from birth, and the majority of your environmental surroundings are laid firm throughout your early development, your brain maintains the raw potential to grow its own new neurons. The investigators of this study propose that these neurons are involved in tailoring and tuning our behaviors, implying that the way we live our lives may make us who we are.

So, how does this happen? We don’t actually know. No disrespect intended to these researchers, but any experiment addressing such a controversial, profound, and metaphysically-tangled problem as the nature-vs.-nurture debate is going to generate more questions than answers. It could be that epigenetic changes, where experience modifies gene expression, gives rise to completely different life paths. It can also be questioned just how substantial the differences in roaming entropy could actually be, and whether it was actually statistically significant. Regardless of the specifics and questions left to be answered, this experiment is a reminder that our lives are truly a work in progress. Whether it is our genes, our environments, or generation of adult born neurons, the nature versus nurture debate is yet to be solved. But it seems that if we are living out our lives as a sort of tape, then it’s a tape in which the tracks can be tweaked as they’re read, as our genes can be modified as we live. As your brain is shaped by your life and vice versa, there is so much room for chance and noise – room for you to become you.

The Prophetic Brain: Foretelling Your Future

The act of fortune telling is an ancient practice. Chinese diviners burnt turtle shells and studied the resulting cracks to make a host of predictions, including future crop conditions and weather forecasts, and ancient Greeks read animal entrails in their divinatory practices. While the modern scientific community regards fortune telling as mere hogwash, brain science is starting to use genetic information, environmental conditions, and brain structure to predict an individual’s future actions. Neuroscientists could become the oracles of our era.

One such scientist is Penn professor and neurocriminologist Adrian Raine. In his controversial research, Dr. Raine proposes that the structure of the brain may provide insight into an individual’s propensity to commit a violent crime. In fact, he argues that future criminal offending can be predicted in children as young as three years. In one experiment, Dr. Raine studied 1,800 three-year-old children from the tropical island of Mauritius in the Indian Ocean. In his longitudinal study, he followed subjects for 20 years, noting any criminal convictions. He then compared the criminals with the noncriminals and discovered that the former demonstrated a lack of fear as children.*

Although the findings of Dr. Raine's research are intriguing, the environmental and biological affects on brain and behavior ought to be examined. Child abuse, cigarette smoking and alcohol consumption during pregnancy, and poor nutrition give scientists great predictive power regarding individuals' outcomes. For example, children of moms who smoked tobacco while pregnant were 2-3 times more likely to be violent criminals by age 20, and pregnant women who consumed just 1 drink per week birthed children who were 30% more aggressive than their peers. Poor nutrition during prenatal and postnatal development also leads to greater antisocial behaviors in children.

Additionally, genetics, brain structure and function, and testosterone levels have a tremendous influence on behavior. Using EEG to study the electrical activity of prisoners' brains, Dr. Raine noted that violent criminal offenders demonstrated poor-functioning prefrontal cortexes, the part of the brain associated with the regulation of behavior and emotions. The amygdala, which is responsible for emotions, is also implicated in antisocial tendencies.  For example, sociopaths have been shown to have an amygdala 18% smaller than individuals without sociopathy.

While it is extremely enticing to regard the brain as quasi-prophetic, it is necessary to consider the ethical dilemmas and misguided conclusions that can be drawn from related research. The following questions are helpful in understanding the consequences of such work: Could neuroscience research be used to fuel a eugenics movement? Is it possible to reduce antisocial tendencies in adulthood by enriching the brain in childhood? Are brain structure and function reliable predictive measures? Does brain structure lead to violent behavior, or does a violent lifestyle lead to changes in the brain? Dr. Raine explores some of these concerns and more in Radio Times with Marty Moss-Coane.

*The amygdala is critical in fear conditioning.

Welcome to the Mind-Meld

The way that current research is progressing, our brains may be closer than we ever thought… Ever wanted to know what someone else was thinking? We may have found the answer to connecting human minds – not only figuratively, but literally. Very literally.

Picture this: a scientific experiment, involving two rats. The first rat pressed a lever, as it was trained to, anticipating the reward it would receive for completing the task. An implant in this rat’s brain then converted its neural activity into an electrical signal and beamed the impulse to the second rat. The second rat then jumped forward to press the lever in its own cage… but this rat had never been trained to ever press a lever. The movement impulse it had to press the lever came not from its own mind, but directly from the brain of the first rat, who was in fact thousands of miles away.

What was created in 2012 by lead researcher Miguel Nicolelis was “a new central nervous system made of two brains.” After successfully connecting the brains of two rats, other labs were quick to pick up on the research and one-up Nicolelis’s experiment. A team of researchers at Harvard University engineered a brain-to-brain interface between a human and a rat in the summer of 2013 that enabled the human to control the rat’s tail movements by merely willing them to happen. Pretty crazy…

Then in August 2013 came the final leap that everyone had been waiting for. Scientists Andrea Stocco and Rajesh Rao from the University of Washington successfully created science’s first human-to-human brain-to-brain interface. One person was strapped into a transcranial magnetic stimulation (TMS) helmet, while the other was strapped into a non-invasive electroencephalogram (EEG) helmet – the two researchers became successfully mind-melded in the name of all things science.

The Experiment:

Rajesh Rao and Andrea Stocco, one strapped into each type of helmet, were placed across campus from one another while watching the same video game. Rao was wearing an EEG helmet, a non-invasive device that detects the neuronal firing activity of millions of different neurons underneath the skull. He was also in charge of the controls of the video game, but instead of actually using his hand to hit the spacebar and fire on the video game, he simply imagined moving his hand. Each time he made the conscious thought to fire, an instantaneously fast computer converted the brain signals emitted by Rao’s EEG helmet into a digital signal which was then beamed to a TMS helmet on Stocco’s head. A transcranial magnetic stimulation helmet (also non-invasive) electrically stimulates neurons in particular areas of the brain by creating a small electric current. The helmet attached to Stocco’s head converted Rao’s signals into bursts of magnetic stimulation that were delivered to the exact region of Stocco’s motor cortex that controlled his right hand. The signal would cause Stocco’s hand to involuntarily twitch, sometimes even scoring a hit in the game.

Rao stated that the experience felt very different for both of them. “For me, it was only ater the action had occurred that I had the chance to reflect upon what had happened – that it was Stocco’s hand, stimulated by my brain signal, that had caused the action. That realization was both exciting and a bit eerie.” For Stocco, all that was really felt was an involuntary muscle twitch that caused his hand to move and hit the keyboard. There was no conscious “need” to flex the muscle, he said, because the entire sequence from stimulation to movement happened within a few milliseconds. Moreover, Rao noted about Stucco, “I don’t think he can resist the movement once he’s received the stimulation, since it operates at the subconscious level.” Definitely pretty eerie…

Test Hurdles:

Even with the level of connectivity that was reached at the sub-conscious level, the process revealed that it wasn’t flawless or error-free – and this exposed some interesting discoveries about how our brains process information.

The EEG device used by Rao (which sent the outgoing brain signals) uses technology dating all the way back to 1875. Although today’s advancements in technology are obviously far greater than those of 150 years ago, they still operate on the same basic principle. Electrodes are placed across a person’s scalp that pick up frequencies oscillating within that person’s brain. Because of this, EEG signals can’t pinpoint activity to a specific 3-dimensional point in the brain, but they are handy for tracking large-scale brain impulses. TMS technology is much more recent – and much more controversial as well. It works by disrupting activity deep within the brain by using electrical signals, and some researchers have even reported seizures being triggered as a side effect of TMS. However, most researchers today agree that the risk is small, and many have succeeded in using this technology to trigger movement, increase memory, and treat depression. Rao and Stocco also both agreed to use these procedures because they were non-invasive, making this technology the clear choice. “Andrea and I got really excited about the idea, and we started brainstorming,” he said.

Leading up to the experiment, Rao had to go through quite a bit of brain training in order to successfully execute the experiment. “EEG signals are quite hard to use for controlling devices,” he explained, “because the signal is a weak, noisy, filtered version of the underlying brain activity.” Any extra movement of the eyes, face, or body—or even stray thoughts—could interfere with the signals and give false readings. Rao had to learn, through trial and error, how to control his EEG output more accurately by remaining focused. Finally, in the last session, Rao and Stocco achieved nearly 100% accuracy in the test.

What Now?

Now that scientists have created a full-blown mind-meld, what next? One of the important things to note is that the experiment was built on technology that’s rapidly becoming part of the consumer marketplace, as TMS and EEG devices are becoming more readily available. And, even though this test only transmitted movements from one mind to another, it is the hope of scientists that in the future, we could (theoretically) learn to transfer perceptions, concepts, emotions, and even thoughts. Then we would actually be talking about a REAL mind-meld, allowing people to communicate directly through their brains. As long as humans have been around, the need to communicate thoughts clearly and understanding the minds of others has been an overwhelming desire – the fact that we are this close by putting on little plastic helmets to watch what’s happening inside our brains is both exciting and a little bit scary. Where do you stand? Technologies like this might seem to have the potential to turn us all into robots – or edge us towards a future of communication, understanding, and human contact more intimate and direct than we’ve ever experienced. Where do we draw the line between human connection and complete invasiveness? The thin line is becoming a little bit eerie. Still, the effects of the mind-meld are yet to be discovered…

via Discover Magazine, The Crux

The Brain: Wired To Connect?

Recently, Scientific American covered an interesting interview with scientist Matthew Lieberman, who discussed ideas on the neuroscience of human connections, and the implications behind how we live our lives. As human beings truly are such social creatures, Lieberman took the initiative to explore the social needs we have to connect with one another, analyzing this in regards to brain function. So whether out at social events, hanging out with friends, or (surprisingly) even when we’re alone – our brain is wired to be set on social interaction. In his interview, Lieberman reflects with his insight on these topics.

Our need to connect socially is “powerful.” But just how powerful is it?

Lieberman asserts that our need to connect is as fundamental as the need for food and water. Cultures around the world all have different beliefs about how important community and social interdependence are to our lives. Here in America, and in the West, we tend to believe that we are relatively independent and self-focused, immune to the sway and opinion of others around us. We like to think that we are driven to pursue our personal goals – but according to Lieberman’s studies, we may be less socially independent than we’d like to believe.

What is the connection between physical pain and social pain?

When we experience social pain – a rejection, harsh words – the feeling is as real as physical pain in our minds. Around the world, we use physical pain language to describe emotional or social pains we feel (“he broke my heart,” “she hurt my feelings”). This may be less of a metaphor than at first glance. With respect to human nature and evolution, this finding is pretty interesting… The things that cause us to feel physical pain are things that our brain recognizes as threats to our survival. The existence of social pain indicates that somewhere along the line, evolution treated social connection as a necessity rather than a comfort. Social connection also motivates us in behavior, influencing our decisions to revolve around praise from others and alleviating social threats. Social pain and pleasure are wired into our operating system, even though we never actually consider these as factors motivating “who we are.”

Human mind reading – what is it, and why is it important?

Not in reference to ESP psychic mind reading, this is a skill we use each and every day in social interactions. It’s kind of strange to think about, but humans have a tendency towards trying to understand the thoughts and feelings in the minds of people we interact with. Lieberman asserts that although we are far from perfect at deciphering the inner thoughts of others, the fact that we can even do this at all gives us an “unparalleled ability to connect and cooperate with others.” So in actuality, at times we are using other’s goals to motivate our own behaviors. Strangely enough, thinking about other people’s thoughts doesn’t feel any different from most kinds of analytical thinking we do. Yet Lieberman’s studies of fMRI research show that there are actually two distinct brain networks that support social and non-social thinking. As one of these networks increases its activity, the other one stops its functioning, like a “neural seesaw.” Here is the most fascinating part: whenever we finish doing some kind of non-social thinking, the brain network for social thinking comes on again almost immediately. Why would our brains be wired this way? Research has recently suggested that perhaps this reflex prepares us to enter the next moment of our lives focused on the thoughts behind the actions we see from others. Evolution has placed social functioning highest in our brains, making a major statement about the social nature of humans.

Shedding light on the age-old question: where does the “self” come from, and what does the “self” even mean?

Social psychologists have speculated for a long time that the “self” is a much more social phenomenon than it feels like from the inside, and neuroscience is bringing in new data to directly shed light on this. The region of the brain called the medial pre-frontal cortex, which sits right between your eyes, has been shown repeatedly to become activated when people reflect on themselves. Because we tend to think of the “self” as the thing that separates us from others, it is surprising that the same medial pre-frontal cortex is activated when we allow the beliefs of others to influence our own. The more active your pre-frontal cortex is when someone is trying to persuade you of something, the more likely you are to listen. Rather than being a closed-off area that separates us from others, the “self” is actually a socially-influenced idea, where the ideas of others are subconsciously considered in order that we may have the same kind of beliefs and values as those of the people around us. So the “self” we think of is truly much more an incorporation of the people around us, although we don’t consciously realize it.

So, according to Lieberman’s neuro-scientific research regarding the social nature of the brain, you actually may care what others think just a bit more than you realized… after all, we may be wired to care.

Scientific American, Mind Matters.

http://www.scientificamerican.com/article.cfm?id=why-we-are-wired-to-connect&page=2

Music, Memory, and Awareness of Self

Here at Penn, the 2013-2014 Academic Year has been dubbed “The Year of Sound,” gathering the Quaker Nation to celebrate all things musical, harmonious, noteworthy, and rhythmically driven. We’re all dancing (and learning) to the same tune! And as someone interested in neuroscience – which if you’re reading this, I’m sure you probably are as well or you're on the wrong page – Penn could not have picked a more exciting topic to delve into for all things brainy. Sound and the brain often go hand in hand, as scientists and researchers study effects of music on the brain, the way we process sound, clinical music therapy, and sound and memory, among other endless possibilities. I came across an interesting article regarding music in Alzheimer’s therapy, and immediately was drawn to the idea of music and the brain linking to this year’s theme, Year of Sound. So whether this gets you excited about music, memory, or self-awareness, keep both your ears and your brain open to this noteworthy breakthrough in Alzheimer’s research.

As most people probably know, Alzheimer’s disease, the most common form of dementia, is a neurodegenerative disease characterized by rapid and progressive decline of cognitive function. So far, there has been very little effective treatment for AD, so many have turned to interest in treating Alzheimer’s with behavioral therapy rather than drugs. A broad array of treatments have been investigated to battle this disease, including cognitive training, sensory stimulation, music therapy, and motor stimulation – of which music therapy seems to gather the most interest and results. For some reason, several different studies have shown that in Alzheimer’s patients with moderate to severe AD, their music memory has often been preserved despite of severe impairment in other areas. Several studies have shown that music therapy in Alzheimer’s patients can often alleviate some symptoms and reduce dementia troubles, overall improving healthy cognition, memory, language, and depression or anxiety. However, several researchers in Spain recently set out to examine the effects of music on a slightly different aspect of patients that is lost -- self-consciousness.

Self-consciousness is a characteristic thought to be unique to humans and some apes, separating higher thinking from that of other mammals. Basically, self-consciousness is an awareness of self, an ability to separate ourselves from perception and realize that we are perceiving. Descartes’ aphorism “I think, therefore I am” is the object of self-awareness, an understanding that we can realize we are thinking, and deduce from that our own existence. SC is multi-faceted, including consciousness of the body, its characteristics (i.e. if we are blond, brown, big or small), perception (senses of sight, smell, taste), one’s own autobiography, judgment, and moral decisions. Self-consciousness is a cognitive trait that allows us to be aware of the people we are, what we think, and act by moral reflection. So, in extreme cases, a loss of SC involves the subject no longer being conscious of existing. (Crazy to think we can be alive, yet not know we exist…)

Because music therapy has been shown to improve many symptoms of Alzheimer’s, Gil et al set out to discover if familiar music exposure could improve self-consciousness in cases of Alzheimer’s. 40 patients were recruited from the Memory Clinic in Salamanca, Spain to participate in the study, divided into a control group and an experimental group. 11 familiar songs were chosen for the experimental group and 5 unfamiliar songs were chosen for the control group. To assess levels of self-consciousness, patients were given an SC questionnaire that asked questions regarding personal identity, affective state, body representation, future memory, self-analysis, and moral judgments. They were then exposed to three months of intervention period in which they listened to music as part of daily therapy, and then followed up with the same SC questionnaire. After analyzing the results of the questionnaire, comparisons between the experimental and control groups showed that there were significant differences between the pre and post states of self-consciousness. The experimental group improved significantly in personal identity, affective state, moral judgment, and body representation, whereas in the control group there was impairment in almost all aspects over the three months. The three months of familiar music exposure integrated into daily life appeared to strengthen self-awareness and cognitive mental perception, while the control group continued to decline in state of consciousness.

So what does this mean? Maybe familiar music can be considered an overall enhancer for both self-awareness and mental state of being. Why did unfamiliar music therapy do nothing for patients? It is thought that unfamiliar music may require more processing of short-term memory, which is greatly affected in Alzheimer’s patients, whereas familiar music may trigger involuntary memories by favoring events formerly associated with the music. So it can be proposed that prolonged exposure to familiar music could allow AD patients who have lost other social and cognitive skills to participate in life and gain a sense of their own existence.

Being self-aware is not something we normally think about. How often do we actually take the time to consciously think about our own perception and existence? It’s not exactly something we value, yet in Alzheimer’s patients an ability to recognize ourselves is sadly lost. Who knew that our favorite songs could be the link to bringing us back into existence?

Familiar Music as an Enhancer of Self-Consciousness in Patients with Alzheimer's Disease

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3784147/