Language in Animals

Have you ever really thought about the complexities involved with learning a language?  Try for just a moment to list all the grammatical rules involved with language production.  I don't know about you but I can hardly think of 5.  Yet we unconsciously make very complex sentences all the time.  What's more, we're not just parroting what we hear from those around us.  New combinations of words are created everyday!

But this leads us to the question- are human beings the only ones with the capacity to create and use complex language?  The literature on the science is quite divided.  I even have mixed opinions on the matter as I think we do not appreciate the intelligence of most animals.  But is there is one particularly empirical study by a man named Herb Terrace who seems to provide the most unbiased research.

It should also be noted such studies have the added
difficulty of undomesticated behavior such as biting.

He took a young chimp (named Nim Chimpsky after the linguist Noam Chomsky) and had a human family raise him in their urban home.  Due to physiological differences between humans and apes, chimpanzees can not properly vocalize human speech.  So, the family raised their young Chimpsky by teaching him sign language.  He learned about 125 signs which is a pretty decent array.

However, when Herb Terrace returned for rigorous testing, he found no evidence of language use.  Nim could use signs he had been taught, but he could not create novel sentences.

Now I will by no mean argue this is the only such study performed with apes.  The literature is full of evidence and counter-evidence for other species understanding complex language.  Unfortunately many of these studies are hard to assess because of how attached the researchers become to their animals.  Just as pet owners swear their dog knows exactly what they're thinking, researchers are prone to bias about their animals as well.

Reknown linguist Noam Chomsky.

So, I leave the question in your hands- how well can animals comprehend language?

Language in the Brain

I want to start this post by first stating the oft-repeated paradigm that you're either "left-brained" or "right-brained" has almost no scientific basis.  Your brain is basically a mess of biological wires in the form of axons.  Information crosses from one hemisphere of the brain to the other along the corpus callosum as well as other minor pathways.  Without both parts of your brain, you cannot function normally.  (Just look at patients with hemi-neglect.)  That being said, there are certain functions which are lateralized to one side of your brain.  Language -both comprehension and production- is a key example.

There's a particular experiment called the Wada Test which demonstrates this lateralization particularly well.  The participant is injected with a temporary gaba agonist through the left carotid artery.  Gaba is an excitatory signal so by blocking it, you essentially put the left hemisphere of the participant's brain to sleep.  The participant remains conscious, though they lose the ability to use the left side of their brain.

The interesting bit is that they lost the ability to compose speech.  You can ask them questions but they will be unable to reply in a coherent way.  But if you give them a matching task that requires both comprehension and identification, they are able to preform it easily.  Their main impediment is their verbal abilities.

Wada testing

But the really curious part is that this doesn't work on everyone.  Because although nearly all people have their language centers lateralized to the left side of their brain.  About 95% of right-handed people and 70% of left-handed people have their language centers based in the left hemisphere of the brain.  But in those remaining 5% and 30%, they seem to have a less focused center for language.

Not much research has been done on this topic.  It's unknown why left-handed people are more prone to the un-lateralized form.  But one possible indication is an inability to remember/distinguish between right and left.  So if you have a chronic problem of separating right from left and are left handed, there's a good chance your language center isn't in the usual location of the brain.

Attention

You say to your mother "of course I'm paying attention."  But what does that really mean?  In the last few decades, neuroscientists have begun to tackle some of the more difficult behaviors to explain.  And just like the advances in emotion have come a long way from freudian suppositions, our understanding of attention has begun to grow as well.  At least, depending on your definition of attention of which there are many.

Go ahead.  Take a moment to formulate in your mind what the correct definition for attention should be.  Remember you don't want to be too vague but nor can you make it too specific.

Perhaps some of your definitions went like this:
1. Prolonged dedication of neural processes to an external stimuli
2. Information stored in the short term/working memory to be used in current actions
3. Sensory information of which you are consciously aware
4. Using neural processes to monitor the environment for an unexpected outcome
5. The focal center of awareness

All of these definitions have elements we want to intuitively agree with.  However, they also have pieces which don't work in all life situations.  And we're still left with issues such as "is attention a physical or mental process?"

"Can you attend to more than one thing at once and still call it attention?"

"What does it mean to shift your attention?"

My personal favorite definition is that of William James.  He described attention as a spotlight which focuses on that which we are attending to.  Sometimes you can see on the periphery of that spotlight but most of the time you deal with what is in the center of the light.

Famous American psychologist William James.

But basically, I wanted to share today how difficult it can be to define something which we all find intuitive in our daily lives.  Please comment and let us know- What's your definition of attention?

Depression and its Treatments

I deeply apologize.  I've let this past week get the best of me as I have been extremely, ridiculously busy.  My apologies for not updating on the regular basis as I have in the past.  But I really will try to keep to a more consistent schedule from here on out.  And to get started, let's talk about depression!

Ok, so maybe I said that with a bit too much enthusiasm.  It's just the idea of something so hard to pin down- like emotions- coming from a neurological basis fascinates me.  Surely we all want to believe our moods aren't caused by the whims of our neurotransmitters and synapses.

This Van Gogh painting is the first thing to
pop up when you search for "depression"
via google.

But there is plenty of strong evidence that explains depression (or at least most of its varieties) stem from a lack of three neurotransmitters.  Serotonin, norepinephrine, and dopamine are the main ingredients lacking in a depressed individual.  And most of our modern treatments try to enhance these neurochemicals in some way.

MAO Inhibitors were part of the first generation of anti-depressant drugs.  They blocked an enzyme which breaks down monoamines.  All three of the transmitters mentioned above fall into this category so the MAO inhibitors basically kept them circulating in a persons system for a longer period of time.

Then came the tricyclics.  Their primary focus was preventing reuptake of serotonin and norepinephrine by the surrounding cells.  Once again, this keeps the transmitters in the brain for a longer period of time so they can be more effective.  And tricyclics had less side effects than MAO inhibitors.

The newest of the drug types is SSRI (selective serotonin reuptake inhibitors).  They act in much the same way as tricyclics except they have even less damaging side effects because they are so much more specific.

This is an image of an actual patient who
underwent the deep brain stimulation surgery.

But even with all the pharmacological changes, the most potent treatment is so radical that it has only been tried on a few human patients.  It's called deep brain stimulation.  Basically, a neurologist places electrodes deep into the brain tissue of their patients and switches them on.  Some about the current of these electrodes affects an inhibitory pathway which quiets the subgenal cingulate part of the brain.  Patients report feeloing immediately relief with none of the lag which drugs possess.  They also feel the immediate change if you were to turn off their electrodes- whether they were aware you were doing so or not.  So this isn't just the placebo effect at work.  I'd be curious to see where this research progresses in the future.  Aren't you?

KO'd but Ok

So I know I've been MIA lately but this weekend was one of the biggest events of the year.  Outside of my passion for neuroscience, my favorite obsession is Taekwondo.  And I really don't mean that martial art you did when you were 7 years old.  My type of Taekwondo is where you gear up in light padding and fight for several rounds against an opponent who could potentially knock you out.

The Texas Taekwondo team of 2011-2012 

And this weekend was the National Collegiate Taekwondo Championships.  My team and I travelled to Boston for a weekend spent full of fighting at MIT against some of the best fighters in the nation.  Everyone's year long training regime really showed through and we were a powerful team to beat.  We came away with 3 silvers (including myself) and 1 bronze.

But I'm not here to just brag.  I also found myself raising the neurological question "what exactly causes a knock out?" At this weekend's tournament I saw a good friend and team member of mine get knocked out. I mean he hit the ground and didn't even try to get up for a good ten seconds.  It was sincerely scary.  Afterwards, I watched them take him to the medic station and put him through several rounds of medical and cognitive testing.  In fact, I was put in charge of keeping an eye out for any concussions.

This is what happened to my friend- though this video is of Aaron Cook and Steven Lopez.

When I asked him about the experience, he said his head was a bit sore now but he didn't remember being hit.  In fact, his memory didn't really start recording again until he was seated at the medic station- he doesn't remember standing up.  So what exactly happened to him?

Well after some internet research, I've come to realize that our understanding of knock outs is a little hit-or-miss.  We know that concussions are caused by the brain slamming into the interior of the skull.  But what about knock outs without the concussion?  Some sources say it's short term damage to the brain stem.  But in truth, I couldn't find much on the topic of knock outs without the concussion.  It seems like this should be an area of more study considering the number of contact sports played.

So in a final word- does anyone know where I could get more information on the nature of knock outs?

NeurOlympics

Instead of learning new information in class yesterday, I was afforded the chance to show the progress I've made thus far- both in the classroom and outside.  Because besides today being an exam day in Neural Systems, it was also the long awaited NeurOlympics!

Free t-shirts went to all competitors!

For those of you unaware of this tradition, allow me to explain the premises.  The UT Synapse Neuroscience Club hosts this trivia game show style competition.  Three teams of 4 compete for eternal nerd glory and pretty sweet trophies.

Trophies were handmade
by the wonderful officer Devon!

Questions ranged from psychology, medicine, neurobiology, ion channels, and so much besides!  I participated as part of the "Basal Gang of Four" along with some friends from the club.  I feared that I hadn't taken enough upper division neuroscience classes to be of any help.  My tea members were all older and further along in their degree plans.  However, I proved myself worthy of a few points.

Still, by the end of the first round (out of 3, plus a bonus round) my team was last.  Amazingly, we only gained speed and points from there.  More assertive "buzzing in" and conferring with team members before answering racked up the points.  I honestly believed we wouldn't do well because of our lagging start.  But when all the points were tallied, we proved victorious!

My lucky neuron jewelry
I wore to battle.

I know this was just a small, nerdy competition done for fun.  But I can honestly say I'm proud of myself.  I contributed to our success and proved to myself that I really am learning more everyday.  I'm definitely no expert but if I keep moving at this pace, I know I can create a successful career in neuroscience!

That's right, the Nernst equation!