Science is Hard!

Remember back in the good old days when teachers said "Here's how this works! Just learn the process." and that was it?  I wont disagree that there's a certain element of boredom involved with that style of learning.  But this semester is teaching me that performing real science is so far beyond rote memorization.

It's not easy to get access to up there, huh?

Currently I'm working in a lab on my college campus.  I'm just an undergraduate research assistant but our project is relatively small so I get to handle all aspects of the actual research.  When I first volunteered for the position, I thought all the procedures and general direction of the project were pretty obvious.  We're doing a longitudinal study so it breaks up into neat little chunks.

But halfway through the semester I'm seeing all these sources of error!  I have a bit of OCD and sometimes I wonder whether that's a blessing or a curse for doing academic research.  Let's start with the fact that I do human research.  So we had to start by getting a big enough sample size.  We didn't have grandiose expectations yet you'd be surprised on how difficult it is to even get 10 people to it your research criteria.  There are all sorts of things that can eliminate a person from a psychology study.

And even when they do make it past initial screening, you have to remember that these are people you're dealing with.  People, unlike lab rats, have schedules and plans and can't be kept in a cage in the lab.  So you have to keep an eye on your participants and make sure they keep up with the requirements of the project.  This is particularly important for longitudinal studies.

Ah, and we must also remember the fallibility of technology.  For all the good its done us, our tech is never perfect.  You can have faulty wires or computer programs that wont run or even run out of materials.  Just today, my lab ran out of circular adhesives to use with the EEG and had to run a makeshift version of our preferred methods.  And I've had times when batteries nearly died and the electrical leads on the EEG decided to stop working.  There's just so many little places for a slip up to affect your data.

Obligatory cute baby picture!  Though really I meant to
say I'm still young in my training.

Yet, in a weird way I love that variability.  It makes science hard, but it also keeps it interesting.  You're always striving for the perfect run and the most accurate results.  And a truly good scientist learns to compensate for all the possible external factors.  Trying to design the cleanest. most efficient, most reliability study appeals as an interesting study for me.  But for now, I hope to continue to learn in my current position.

Why Cab Drivers Have Better Hippocampi

Ok, so the title is a little ludicrous.  Cab drivers don't necessarily have better hippocampi.  However, there is evidence that they have better trained hippocampi, so to speak, which allow them to process spacial information in a more efficient manner than the average person.

The hippocampus is a structure in your brain that looks a bit like a couple of protruding fingers horizontal with the temporal lobes.  It's primary function has to do with memory, both consolidation and recall.  In my previous posts I've mentioned examples such as H.M. (Henry Molaison) and others like him who suffered from a deficit in the hippocampus.  But now I want to show how a brain structure can also become better at its function, not  just worse.

The hippocampus is here hi-lighted in blue.

This study originated in the ancient city of London.  Like most old cities, the roads don't form a grid pattern.  Instead they form curves and loops in a jumbled mess like a knotted ball of string.  Also, the streets are not numbered in sequential older like the modern cities of today.  The names are assigned from times long past which makes for some confusing navigating.

Yet a recent study found that the cab drivers of London have more developed hippocampi than those of the average person.   The first instinct was to say that people who have better spacial memory naturally would become taxi drivers.  In other words, a simple correlation could be responsible for the connection they observed.

But further testing allowed for a more definite picture.  The researchers took participants who were training to become taxi drivers in London. (The test to become a cab driver requires that you know 320 routes, 25000 streets, and 20000 landmarks.)  The measured the participants early in their training and found average hippocampi.  But after the participants earned their cab license, the researchers took a second measurement system.  Indeed, the hippocampi of the newly minted cab drivers were more developed, proving it was the training leading to causation of brain change and not just correlation.

Just looking at this map of London increases my respect
for the cab drivers who navigate it.

So next time you think that taxi driving is a brain-rotting job, remember that your cab driver probably has a bigger hippocampus than you do.

Memory Trace Theory and What it Means to Remember

Here at the University of Texas, there's a whole department devoted to the study of learning and memory.  There is constant ongoing research regarding the subject of memory consolidation and other similar topics so we are by no means close to understanding the full processes.  However, just going over the current theory for memory caught me as a bit sad in a strange way.

Memory trace theory holds that when we first experience an event, it is recorded as a declarative memory in the hippocampus.  But with further recall (aka- reliving or remembering the event), it turns into a set of semantic information and is stored throughout the neocortex.

Your memory isn't like storage space in a computer.  It's a
constant organic process.

But memories are just memories, right?  Nope.  Our brains aren't a recorder or a photo album.  When we make the jump from declarative memories (life instances) to semantic (collection of facts), so much is lost.  We will never hold the full memory ever again.  And over time, the semantic facts we've collected can shift and change.  This explains when you and a friend tell the same story from a year ago but with very different details.

Maybe I'm excessively attached to my recollections.  As I've said before, I am the product of my memories.  My life experiences have made me who I am.  Just the past year and a half of college have given me numerous experiences that have radically altered my view of the world- some for the better and some...not. But when I realize I will never be able to keep the stories of my past unaltered by my own neural processes, I'm aware of how much I have to lose.

These are my 17 journals which I have filled with my life
experiences.  I'm currently on number 18.

I suppose it's a good thing I'm such a avid writer.  I keep a journal and every night for the past 9 years (approximately) I've written two page entries.  Sometimes they lean towards the dull side but more often than not I have a nice little story to tell.  So even if my brain can't keep the facts straight, at least I'll have these journals to serve as my window into the past.

Remember that one time when.....

How much of our personality, our soul, is composed of our memories?  I think who we are stems from what we've done and how we've learned from those actions.  But imagine an existence where you could no longer form memories.  This is the situation faced by neurological patient H.M.- now know as Henry Molaison.

Henry Molaison passed away in 2008.

Henry suffered from debilitating seizures caused by tissue in his temporal lobes.  Historically, patients before him had undergone surgery to remove the epicenter in the brain that caused the seizures and this usually solved the problem.  But for Henry, the seizures were caused by 2 epicenters- one on each temporal lobe.  So when surgeon Scoville removed the defective tissue in 27 year old Henry Molaison, he had to take large portions from both sides.

But a strange thing happened when Henry recovered from his surgery.  He was no longer able to form new memories.  Semantic information (facts and dates) from before his surgery was untouched but when it came to recalling simple episodic information (like what he had eaten for breakfast), he couldn't recall a thing.

Neuroscientists Brenda Milner and Suzanne Corkin took on the case of H.M. in the hopes of learning more about memory and its storage in the human brain.  They found that the hippocampus, which was almost completely removed, is vital for processing memories.  You could view it as a sort of clearing house where short term memory gets transferred into long term storage.  But without this structure, Henry could no longer process his memories.  In other words, he was forever stuck in the mindset of his 27 year old self.

Hi-lighted in yellow is the portion that H.M. lost.

A similar deficit was found in a Korsakoff's syndrome patient mentioned by Oliver Sacks in his book The Man Who Mistook His Wife for a Hat.  This man was also unable to form new memories, leaving him trapped in a time that has already passed.

Now while there are some technical differences on the types of memories and amount of retrieval between these patients, they both hold an amount of melancholy in my mind.  To be deprived of the ever changing world.  To be able to grow and expand.  These two men lost so much.

I am a firm believer that our genetics set the blue print but our experiences are really what make us unique. And our capacity to change is what makes us so fantastic.  My heart goes out to these two men and all who suffer from anterograde amnesia.  It's a hard world to imagine.

But what about you?  Would you rather suffer anterograde amnesia (where you can't form new memories) or retrograde amnesia (where you can't remember your past from a certain point back)?  It's no easy choice.

Body, Brain, and Mind

Note: This is actually an essay I had to write for philosophy challenging some of our neuroscience assumptions.  I know it's long so don't feel bad if you don't read it.

As a staunch neuroscience advocate, I do not like to think that there is anything we cannot discover experimentally.  The leaps made in even the past few decades have revolutionized our views of mood, personality, and consciousness.  Yet by the same token, we can never have absolute proof that the mind and all that it entails is identical to the physical organ of the brain.  My argument is that the brain functions much as any other body part, only with a much more intimate connection to the mind.  It can be influenced and changed physically and that will lead to alterations in behavior and mood.  But we have no way to control the mind completely through the brain, only to influence it as an outside factor.  Thus the correlation between mind and brain is extremely weighty, but does not serve as an identity between them.

The first case study in differentiating brain and mind comes from research revolving around lesion studies.  Lesions take place when you damage a piece of tissue so that it can no longer operate.  They often happen incidentally due to injury, but the term is usually used to refer to purposely created deficits in neural tissue.  These intentional injuries allow scientists to study what the loss-of-function for a particular region will do to overall cognition.

Just had to add this cause I love brains!

Over the years, thousands of these studies have been conducted, and while some of them have indicated localized regions involved with highly specific function, more often there are examples of the same small-sized lesions making no recordable difference at all.  Even in practical application, we cause brain damage to ourselves every time we drink alcohol or get a strong bump to the head, yet it takes a large degree of damage to actually affect a change at all.

Examining the larger deficits, such as those which plagued Phineas Gage, we still cannot say with complete certainty what the change will be. The ventromedial prefrontal cortex which Gage destroyed with his tamping iron is involved in decision making.  This much we can state as fact.  But the loss of function does not mean that he used to pick B over A but now he will always chose A instead of B.  The effects are highly convoluted with only a general pattern to guide us.

But an opponent to this stance, a physicalist, would claim that of course this makes sense.  The brain does not equal the mind, for we rarely find such a simple association is rarely found in nature.  Instead, it would make much more sense to narrow the statement to say every mental state we can possess is based on a brain state.  And sometimes the brain states are unrelated to conscious thought or processing. Maybe these states are the parts being affected by the small lesions in the studies mentioned above.

Of course, it is important to recall what we are referring to as “the mind.”  Descartes, from whom this original dualism stems, saw the mind as being a collection of ideas, memories, beliefs, and opinions that can be disconnected from the physical world.  So how can we try to change or alter this state?

Descartes: Author of the Meditations

Much of the psychopharmacology of the current era has been based on the belief that we can alter the mind.  Antidepressant drugs rely on changing the composition of cellular channels and levels of neurotransmitters to help patients rid themselves of emotional problems caused by “poor wiring.”  Another example shows that some pain medications block receptors in the body’s central nervous system to keep the signals from reaching the brain and forming full sensations.  And we even have ways of directly stimulating regions of the brains via implanted electrodes to activate the amygdala and invoke a fear response (Though this experiment has only been done on lab animals so the analysis of the effect on cognition is extremely limited.  Not to mention we have not taken into account the implications of animals’ mental states, as well as the fact that only outward behavior can be measured.).

Nevertheless, despite strong arguments for brain alterations leading to changes in behavior or mood, we still have no conclusive evidence that these alterations are affecting the root initiator of the mind.  With all our modern science and technology, we still have nothing resembling brain control.  We can only change influencing factors on the brain, such as physical perceptions like pain or moods such as depression.  These cannot lead to changes in belief or an alteration of how we recall memories.  Our ideas will remain our own, even if our brain chemistry is altered.

Perhaps the most apt metaphor is to compare the brain to another physical aspect of our being such as an arm.  Just as our brain controls the movement of our arm, our mind directs the brain to change in certain physical ways which will then allow it to function as the mind wishes.  The mind just works through the brain which works through the body to accomplish its ultimate goal- whatever that may be.

And just as environmental changes can affect functioning of a limb like an arm, external factors like psychopharmacological drugs can alter the functioning of the brain.  The key lies in that both are experiencing forces outside their existence which tweak how they respond.  And in the case such as damage to the neural cortices, the result is like breaking a bone in the arm.  You may still hold the same intentions but enacting them is challenged by an injury.

Through these examples I have strived to prove the imperfect connection between the brain and the mind.  The correlation between the two grows stronger as modern science progresses but the link will never be perfectly defined.  As correlation does not equal identity, we cannot say that the two are identical entities.  Thus a modified dualist view -which shows the brain is used by the mind like how the body is used by the brain- still holds sway.

Bird-Brained Bombs?

While Pavlov's dogs and B.F. Skinner's work with behavior conditioning are the quintessential studies of learning for psychology and neuroscience alike, the archives of experimentation have even stranger stories to tell.  Some are gruesome, but others are so absurd that you can't help but marvel at human ingenuity and creative thought.

My favorite example of "the odd" starts in the dire settings of America amidst World War II.  B.F Skinner, the famous behaviorist psychologist, wanted to assist in the war efforts.  In particular, he saw a need for improvement in the missile guidance of America's air craft.  The key issue was, we really didn't have one.  Bombers approximated when they were over their target and then dropped the full payload in the hopes that a few would accurately hit.  The sheer inefficiency of this system sent Skinner in search of a solution.  And what better experience did he have than working with operant conditioning?

His solution was to train pigeons to peck at a target through a glass lens marked with crosshairs.  As long as the target was in the center of the lens, the pigeon pecked at the center and the bomb flew straight.  But if the explosive began to veer off target, the trained pigeon would peck off center (in order to hit the target it saw through the glass), altering a complicated series of mechanisms which would change the angle of the bomb's fins and redirect it towards the target.

The military actually funded a good part of this research and initial tests looked promising.  However, by late 1944 the military withdrew their funding in favor of more immediately promising technology.  The idea was revived for a short time in 1948 and paid for by the Navy but ended permanently in 1953 after computer guidance was shown to be consistently reliable.

An image of B.F. Skinner's pigeon contraption.

Still, I can't help but crack up at the idea of pigeon-headed bombs falling on enemies.  Animal rights groups would be aflutter with animal cruelty and abuse claims nowadays.  Nevertheless, I'm perversely proud of Skinner and his finally thinking "outside the box."


*Get it?  B.F. Skinner is best known for the "Skinner boxes" he used to condition his animals in his initial testing.

Because I had a test today....

I don't really have a detailed topic in mind to dive into.  Instead, I thought it might be fun to bring in a part of my life which has been all-consuming for the past year and a half.  Because yes, while brains are my passion I also hold another activity as my personal addiction.  Here, this'll give you a hint.

I was very excited to score a head shot.

For those of you unaware of the differences in types of martial arts, this is an example of WTF (world taekwondo federation) olympic style sparring.  Since entering college, I've become enamored with the sport of taekwondo and the Texas Taekwondo team here at UT.  We train 6 days a week with the usual weight-lifting and sprints as well as the actual technique required for an effective fighter.

Now I see how this could be mistaken as off the mark from my usual subject.  But a large amount of current research is being done on exercise and its effect on your brain.  Sure everyone knows the old adage, "exercise your mind to stay healthy" but increasing evidence indicates you need a healthy body to house that mind as well.  For example, a study done with rats showed that the animals who got time on the wheel (and were more physically active) had a greater number of new cells in their hippocampus.  This showed both adult neurogenesis and survival of the new cells (provided, there were also other factors involved such as a reduced level of stress).

But simple, monotonous workouts aren't nearly as effective for complex organisms like humans.  Yes getting your heart rate up several times a week will increase your general health,  but the best bang for your buck in terms of exercise is taking up an activity which engages both your body and mind.

My personal sport of choice is taekwondo.  To most, it may seem a brutal brawl where someone is liable to be knocked out with no determining factors besides speed and strength.  But the way that we approach taekwondo at my school, the whole sport is understood as a physical chess match.  Of course you still have to be strong enough to make your kicks perform like you want but there's a much larger element of out-thinking the opponent.  You have to apply pressure, learn to read the signs to discover your opponent's favorite kicks, and then use those against them.

It seems to be simple but things get very complex very fast as you move up in belt rankings.  I started as a yellow belt but currently sit at red, nearly black, and I know I've had to think faster and more efficiently to reach this level.

Cheesy I know, but I think it gets my point across.

Interestingly, instead of my workouts physically and mentally draining me I find myself refreshed and sharper than before.  Taekwondo may eat up over 9 hours a week of my time but I don't feel my grades have lagged because of it.

If you're not already physically active, I highly recommend taking up an activity that challenges you both physically and entally. Don't try just going to the gym to run on the treadmill for a half hour.  It wont give you the same mental boost and you'll be left bored and probably wanting to end your workout regime.  Dancing, tennis, volleyball, basketball, and (of course) taekwondo, all offer an excellent way to stay engaged and fit.

But if you'd like to see more about the strategy behind taekwondo (as well as some sweet fights), check out our upcoming event.  We'll be hosting the Southwest Conference Fight-Offs February the 25th.  I guarantee a lot of excellent fighters and some exciting matches.