Thursday, March 20, 2008

BrainRise



This is just a little something I painted the other day... maybe (hopefully) this is the dawning of a new age in the land of the brain!

Monday, January 28, 2008

Oddballs and the Unexpected

There are many ways to see what the brain is doing during a task. One of the most common techniques is called electroencephalography (EEG), which measures the electrical impulses of the brain collected using electrodes on the scalp. Brain researchers have come to recognize that there are certain brainwaves that characterize responses to a specific class of stimuli. The brainwave that I want to talk about is called the N400.

The N400 appears when a person is presented with a semantically unfitting or 'oddball' (yes, that is a scientific term) sentence. For example, "I spread my toast with jam and socks."

Recently, researchers have been arguing about whether or not people integrate context information when processing the meaning of sentences. By arguing, I mean passionately writing papers and designing definitive experiments.

So this Dutch scientist, van Burken, thought "Well, if conext information IS integrated in language processing, the 'oddball' effect (the N400) should happen when a perfectly acceptable sentence is presented in an inappropriate context." So he presented the same sentence ("I would like a glass of wine.") twice; once in an adult voice, and once in a childs voice. Sure enough, viewers showed an N400 response to an entirely acceptable sentence in an inappropriate context!

I love elegantly designed experiments like this one because even though we intuitively understand something (like that context is a factor when we are interpreting meaning), conclusive scientific evidence for it can difficult to come by.

Saturday, January 19, 2008

Music Make Me Lose Control

My father was scanning the headlines and he came across a news article about a woman who had MUSIC-INDUCED epilepsy! They call it musicogenic epilepsy, and according to the hospital that treated her, she is one of 5 such cases in the world today.

Epileptics of this sort experience seizures only while hearing music. For this patient, Stacy Gayle, singing in her church choir and listening to music by Sean Paul sent her into grand mal seizures.

Ms. Gayle found that medication didn't really help with her seizures, so she went to Long Island Jewish Medical Center for treatment. Doctors there determined that her seizures came from a single, abnormal region of her right hemisphere. They recorded the electrical activity of her brain (using EEG) and when they saw that she was going into a seizure, they injected her with a radioactive tracer and performed a PET scan, which revealed that her seizures started in a part of her temporal lobe (the medial temporal lobe). To further pinpoint the abnormal region, they implanted a set of 100 electrodes in the right side of her brain, targeting the medial temporal lobe. Once these electrodes had recorded her seizure doctors were able to remove the exact epicenter of her epilepsy (without giving her any neurological deficits!). She has not had a seizure in the 3.5 months since the operation.

For the full article, visit
http://www.northshorelij.com/body.cfm?id=15&action=detail&ref=996

Friday, January 11, 2008

In the Mood for Memory

It's January and I just started a new quarter at UCSD, so I'm going to make a fresh attempt to make a habit of posting when I learn something especially interesting. Maybe, if this works, I'll even do a "Coolest Cog Sci Fact of the Week" sort of thing or something.

So, to begin with, I'm taking a class called "Learning, Memory and Attention." In her first lecture Dr. Sarah Creel (my professor) told us the most interesting thing about memory. She was giving us a few scientifically informed study tips, like study a little bit at a time and be sure that you understand the concepts well enough to explain them to your grandmother and caffeine and exercise help consolidate memory, etc., when she mentioned that it is important to study in the same state of mind that you will be in when you take the test. In other words, memory is functionally dependent on your brain state.

Here's her illustration (note: stories and concrete examples are amazing ways to make a concept memorable). A friend of hers, lets call her Carly, was an undergrad at Berkeley taking calculus. Carly was also on crack. When she studied she was on crack, when she went to class she was on crack, when she took tests she was on crack. Carly got an A in calculus. At this point Dr. Creel made sure to disclaim that "This isn't a drug endorsement, and crack doesn't make you smarter." Over the summer Carly got clean and when she came back in the fall she took the next calculus class in the series. Carlys new teacher gave her a test to see how much of the material from the previous class she had retained. She got an F. The sober Carly couldn't remember the things that the drugged Carly had learned. So, Dr. Creel said, the moral of the story is that you should make it easy on yourself by studying AND testing sober.

Great story, but I am much more interested in the implications this has on the nature of my own identity than improving my memory. Think about it. This memory principle applies to our brain states in general (i.e. our overall mood and neurochemical activity) rather than specifically just drug-induced brain states. In practice this means that, for example, when I am depressed I most easily remember episodes and information that I encountered during past periods of depression (by depression I mean a mood, not clinical depression). We've all experienced how our moods seem to feed themselves, but just think about it in terms of identity. Identity is essentially composed from a series of key memories about the experiences that we have had and what we have made them mean about the world. If I am building a definition of myself (to a certain degree) from my own memories, then my understanding of who I am when I am depressed is significantly different from who I think I am when I am happy or calm simply because I am constructing my identity from a different set of memories.

Now, I'm definitely no expert, and I haven't done any experiments to investigate this further (yet), but I have a few theories (or rather, informed intuitions) about the nature of self and identity. There are a ton of real-life illustrations of how a 'person' can behave as though he/she is actually a series of distinctly different people (generally speaking, in terms of personality traits and behavior). Obvious examples are people with Multiple-Personalities Disorder and people who are bipolar, but the same principle can be seen in perfectly functional, well-adjusted, 'normal' people. For example, a woman uses significantly different behaviors and cognitive strategies (she assumes an entirely different role) when she is interacting with her child than she does when she is interacting with her husband. Our culture and our immediate context (our social role and mood)help us filter out memories that aren't appropriate or are inconsistent (in terms of our social context). I definitely need to do a whole lot more thinking (and maybe some research) about this, but if any of you have any thoughts on the subject, please do share them.

Sunday, November 4, 2007

Out-of-Body Experiences Aren't as Far Out as You Think.

Hey All! I've been neglecting my blog for the sake of science, but never fear, I've found loads of really intriguing things to share with you!

Today's tasty tidbit comes to us from radio WNYC's podcast show "Radio Lab", a show that investigates a wide assortment of cutting-edge and curious topics in science. Their podcast is available in iTunes.

During their "Where Am I?" issue on body image, Jad Abumrad and Robert Krulwich explore the relationship between brains and bodies and how they can get way out of synch. Here's just one item from their show.

In the summer of 1952 the pilots-in-training at Luke Airforce Base suffered 9 fatal accidents during routine training exercises. Another pilot from the same training group reported that once, during a training exercise he felt as though he was sitting on the wing of his plane watching someone (actually himself) fly the plane. Eventually he realized that he was watching himself and resumed conscious control of the plane.

They called in Jim Whinnery, Chief Flight Surgeon and Chief Aeromedical Scientist at the Naval Air Warfare Center. He decided to put volunteer pilots in a centrifuge (the whirling mechanisms used to train astronauts) that had been set up to feel and work like a cockpit and see if OOBs can be induced. The body goes through a specific sequence as the centrifuge gains speed: first the blood is pulled from the brain, and you experience 'gray-out' vision, followed by tunnel vision, black-out, and, if you take it far enough, you lose consciousness. When the pilots come to they are very disoriented, they don't know who or where they are or what they're supposed to be doing. Then it all comes back to them in a rush.

Whinnery tested around 500 pilots in 15 years and recorded their experiences. He noted that the average black-out lasted 12-24 seconds. During black-outs pilots experienced strange visions, so of which included OOBs. Whinnery thinks that the visions happen when the brain loses communication with the body. The visions are the brains way of explaining its sensory experience to itself.

Of the 500, 40 had OOBs. Of that 40, a small subgroup had visions of a tunnel with white light. They were the ones with the most intense black-outs.

As far as I'm concerned, this discovery poses way more questions than it answers. Any thoughts?

Saturday, June 9, 2007

Brains, Computing and Computers



This an amazing talk about brains and brain theory from the guy who invented the PalmPilot. Totally worth 20 minutes of your life.

Friday, June 8, 2007

Myspace, Myworld, Myself

I found a really interesting snippet in the latest issue of The Atlantic about some of the social implications of the Myspace generation. Some psychologists have used a"Narcissistic Personality Inventory" test to measure how 16,475 college kids (starting in 1982 and continuing through 2006) view themselves. The results? "Overall, almost two-thirds of the most recent sample display a higher level of narcissism than the 1982 average." They further noted that students born after the invention/spread of the internet (i.e. the demographic most likely to use sites like Myspace and YouTube) are especially prone to narcissism.

Myspace aside, increasing narcissism is a source of concern because independent studies have showed that "narcissists have trouble forming meaningful relationships, tend to be materialistic, and are prone to higher levels of infidelity, substance abuse, and violence." I find it ironic that the same system that makes it amazingly easy to connect with people may be a reason that young people are becoming more self-involved.