Goodbye Champaign, IL.

This is for all my friends past and present in Champaign-Urbana, IL. And this is difficult.

It is difficult to say goodbye to you. It means I cannot see you as often as I like. It means that our paths will go separate ways. It means that all the things we've experienced together in the past will be faint memories and I cannot touch them.

This has been and always will be my home. For here is where I have left a part of my heart. That part will very soon split into a hundred pieces, and each go their own way to various parts of the earth. Is this not the most painful thing in the world?

Till we meet again.

Reduced Neural Selectivity Increases fMRI Adaptation with Age during Face Discrimination

Key project finally published! This took quite a while, but it was worth it.

[Link to article if you have journal access]
[Link to Pubmed abstract access]

By Joshua O., Goh , Atsunobu, Suzuki , Denise C., Park
Beckman Institute, University of Illinois, Urbana-Champaign, IL, USA; Center for Vital Longevity, University of Texas, Dallas, TX, USA.

Ventral-visual activity in older adults has been characterized by dedifferentiation, or reduced distinctiveness, of responses to different categories of visual stimuli such as faces and houses, that typically elicit highly specialized responses in the fusiform and parahippocampal brain regions respectively in young adults (Park et al., 2004). In the present study, we demonstrate that age-related neural dedifferentiation applies to within-category stimuli (different types of faces) as well, such that older adults process less distinctive representations for individual faces than young adults. We performed a functional magnetic resonance imaging adaptation experiment while young and older participants made same-different judgments to serially presented face-pairs that were Identical, Moderate in similarity through morphing, or Different. As expected, older adults showed adaptation in the fusiform face area (FFA), during the Identical as well as the Moderate conditions relative to the Different condition. Young adults showed adaptation during the Identical condition, but minimal adaptation to the Moderate condition. These results indicate that older adults' FFA treated the morphed faces as Identical faces, reflecting decreased fidelity of neural representation of faces with age.

NeuroImage, In Press, Accepted Manuscript, Available online 6 February 2010

Slicing up HM's brain

Watch HM's brain being documented, slice by slice.

Click here for live link. At the time of this posting, they are already at the occipital structures. So they may finish soon. Not sure what will happen to the link or the video once this entire process is done.

HM was a famous epileptic patient who had much of his medial temporal structures removed as a treatment for the epilepsy. The result of this operation rendered HM unable to form new long-term memories. This finding was instrumental in the notion that the medial temporal structures, such as the hippocampus, is important for memory. Since his operation, HM has been heavily studied. HM passed away on the 8 Dec 2008 due to respiratory failure. [More about HM]

PhD Degree

Got my degree today in the mail. This has got to be the hardest sheet of paper to obtain in your lifetime!

Boston 2009

This is my first time to Boston, the beginning of America. The brief history is that the revolution of early settlers began here against the British colonialist at the time. It was a bunch of people living in Boston Commons, who held radical views of freedom, that banded together and stood up to the military authorities at the time. Today, Boston is full of history...and oysters.

In fact, Charlene and I are here for the Psychophysiological Society annual meeting. This is the 50th anniversary of the conference and there was much to celebrate. This was my first time to attend this conference, and I was a little unsure of what to expect. Of course, this is not a neuroscience conference, so I did not expect to see the usual crowd. But to my surprise, I actually met a lot of old friends here. A bunch of people from the cognitive aging group, some people from Singapore, some friends from Japan, and a lot of people from Illinois! It felt good that this conference was, to me, more about meeting people than it was explicitly about the posters and talks, although some of those were interesting.

Back to the oysters. Have I ever told you that Boston oysters (which are actually mostly from Maine or at least, further out at sea and are so technically not from Boston), are awesome? You can taste the sea in them. Basically, you should eat these raw. Don't even bother with the lemon, and don't drown yourself in oysters. Have a few, like 3 or 4. And stop. And let the ocean water that was sucked up by the oysters cleanse your body as it permeates your mouth. Seriously, that's really what its like.

Fortuitously, we also met an old Singaporean friend who brought us to an awesome place farther out from Boston (Chung Shin Yuan) for the best bowl of 牛肉面, 豆漿 and 油條 that I have had in a long time.

And now...back home! Yay!

PhD

Well, it is the start of the first weekend after defending. How was the defense? It was utterly fun. How often can you squash 5 brilliant minds in one room and have them talk about your work? How often can you debate with them and have them listen to your thoughts on things? How often can you hear them agree or even disagree with you in the most honest sense of it all? I would wish this on anybody who dares to try.

No one knows it all. But the defense is about stating what you know, and what you know you don't know. It is about being honest, and seeking truth. If what you find is real, it will bear itself. If what you think is true, you will find it. Sound familiar?

After the defense, we all went to Jim Gould's to have dinner. And it was, how shall I put it, fun! I think I felt it, that warmth of accomplishment. So that food tastes better. Sweetness has a fragrance, salt floods with depth, sour comes with juiciness, and bitter? There is no bitter.

Soon after, we watched an amazing movie - Inglorious Basterds! What a choice right? Brad Pitt was brilliant. Incidentally, Brangelina was in my defense.

The next day, I cleaned up the mess that was my apartment. It felt good to exert mindless sweat. The day after, we watched Mamma Mia. Tomorrow, BBQ!

That's what PhD is about, what happens before and after.

3T Trio finds a new home in Beckman Institute

The Siemens 3T Trio is a full body MRI scanner. The Beckman Institute just recently acquired it. Today, the machine was brought to the basement of the Beckman building and we were fortunate enough to have some free time to glimpsed part of the process.

The scanner was brought in through a hole they have in the back of the building. It had rained the night before, so the ground around the hole was a little soggy. More importantly, they had to move fast because more rain was coming. The movers had to remove the heavy covers on the hole, lift the magnet bore and lower it into the basement, where there is a trolley for them to push the magnet into its final place. The movers took a break halfway because the rain did come anyway, before they could finish, but they continued later. As far as I know, the scanner is in the basement now, just waiting to be tested and used!

This is a full-body scanner, compared to the head-only scanner 3T Allegra. It should provide more uniform signal, although the 3T Allegra is sometimes better for certain sequences, or so I hear. So we'll see which one shines. They will move the 3T Allegra, head-only scanner, which is right now at the BIC down south, up into the Beckman basement as well, once this Trio is fully functional. There will still be about a month or so of testing and installation before we can begin to use it.

If you are my Facebook friend, you can check out other photos I have of this there [Facebook photo link].

An evening at Harvest Moon Drive-In

We went again to Bayern Stube, the German restaurant at Gibson City, just 40 min away from Champaign by car. This was to celebrate Sylvia's completion of her defense and graduating! Bayern Stube sells great beer and sausages, not to mention awesome desserts. Creme brule there is a must.

After dinner, we watched Year One at the nearby Harvest Moon Drive-In theater. Back in the good old days in Singapore, we used to have one drive-in theater at Jurong. This was taken over my mediacorp and turned into some place for housing film sets.

Harvest Moon Drive-In as two screens, and the thrill is not so much the movie, as it is the feel of sitting out under the stars, watching a screen, straining your ears to hear the dialogue from other peoples' car radios (you don't turn on your own because you are afraid the car battery will die out). And have that venture thwarted because the local train rolls by, chugging along on the metal tracks just behind the screen. The mosquitoes make a full meal out of you. Some people bring their sofas out behind the back of their trucks, some people bring their bbq. As the sun sets, the sky is glorious. All these make the movie a wonderful experience, no matter what the movie is about!

VSS Conference Day 4: Demo Night Exhibit

VSS Conference Day 4: Demo Night Dinner

VSS Conference Day 4: Beach Day

VSS Conference Day 4: My Poster

This poster was presented at VSS Conference 2009 [link to VSS website], morning session [download poster pdf]. This study investigated the effect of task instructions on repetition suppression in the brain. Repetition suppression refers to the phenomenon that the brain response to repeated stimuli is usually reduced or attenuated. It is thought that such reduction in brain response reflects less neuronal recruitment, and hence, a more "efficient" way of processing the same information.
In this study, however, I postulated that under certain circumstances, the brain requires more neuronal recruitment in order to effectively process information for task demands. That is, repetition suppression becomes inefficient because it reduces the degrees of freedom that the brain can use to manipulate existing representations.

The study evaluated brain response in the fusiform region to face-pairs morphed at different levels of similarity. The idea is that the more similar face-pairs are, the more repetition suppression should be observed in the fusiform face area. Participants viewed the face-pairs under two different task instructions. The first task made face-pair similarity irrelevant. In this task, repetition suppression was observed to repeated faces. In the second task, face-pairs were made critical as participants had to make same-different judgments about the pairs. In this task, repetition suppression was eliminated.

The idea here is that in the same-different judgment task, the brain has to represent faces as distinctinctively as possible so that subtle morph differences can be detected. Thus, repetition suppression is prevented, possibly from executive function areas that process task instruction and exert a top-down modulatory control in the fusiform area.

The study also shows that there are individual differences in participants ability to exert this top-down modulation to regulate repetition suppression in the fusiform regions. This study was also performed in older adults, which will be reported in a subsequent research article. Briefly though, it is thought that older adults show declines in behavioral performance because of less distinctiveness in cognitive representations. This design is thus useful as a means to measure and related distinctinveness of representations in the brain and how that affects behavior.

VSS Conference Day 3: Illusion Night

Start of Illusion Night! This is an annual event where conference attendees submit their visual illusions for competition to see who's is the best. The top 10 are selected and show their exhibit here at Illusion Night. You can check out the illusions online [link]. The one that really wowed me was the curveball illusion, its the most dramatic one!

VSS Conference Day 3: Club car to beach

VSS Conference Day 3: Walking to the conference hotel

VSS Conference Day 2: Naples Grande

Touring the hotel lobby grounds.

VSS Conference Day 2: Poster session

Check out the poster session.

VSS Conference Day 1: Arriving at Fort Myers Airport

Just arrived at Fort Myer's airport, Florida. It is 80F and humid. Nice. The airport is about 30 min away from Naples. The shuttle will bring us there. More as we go along in the conference.

My View on the Singapore River...Apparently!

Ha ha, forgot that I did this for Elaine long long time ago. Wow! Check out my interview.

http://www.fas.nus.edu.sg/geog/SingaporeRiver/vidz2.htm

Tax Form 2009

I have submitted my tax form again this year. For the record, every year they ask me the same thing about how many times I've traveled in and out of the States in previous years, and I think...does that change every year? So this year I said I was in the States in 2004 from date A to date B, then in 2005 from date C to date D...etc. But next year should I say that in 2004 I was in the States from date E to date F? Basically, are they dumb?