December 10, 2012

Blogging and Microblogging

I'm in the midst of crunch time with a big final project due this Friday, so this post will be short and sweet.

I recently came across this website called BiggerBrains, and it just so happened that they had, a few days ago, posted a blurb on The Value and How-To's of Blogging and Microblogging for Disseminating your Research. Believe it or not, I was a bit skeptical on the effectiveness of blogging when I started this online adventure. However, my wariness on using this blog as a tool to further my research has all but gone away, thanks to my colleagues and and the folks at BiggerBrains.

I would highly suggest you check out the link above when you have a few minutes to spare - who knows, you may end up hopping on the blogging train yourself!

S

December 3, 2012

Music, Memory and the Motor System

Can you take a guess as to what the three things in the title of this blog post have in common?

If you can't, don't fret - five minutes ago I wouldn't have been able to give you an answer either. Funny thing is, I was taking a break from doing work when I came across this on Twitter:




Obviously intrigued, I clicked on the link and was brought to the following page:


The Beatles' Surprising Contribution to Brain Science


As I read this story (filed appropriately under News in Science), I came to several realizations:

  1. Social media is the main (if not sole) reason why people procrastinate as much as they do.
  2. Said social media has the power to influence anybody, anywhere, at any time.
  3. It's amazing how fast you can learn something new.
  4. The Beatles' music is so influential that it surpasses any and every socially constructed standard.
  5. Ignoring your mother will get you far in life! (I should note that this is meant to be a joke, for those of you who are taking me too seriously - I love my mother, and only sometimes ignore her!)
  6. Most importantly, that hearing new music activates motor areas - that's right, not areas involved in hearing, but motor areas!

Before dwelling on this last point a little more, I'd like to write a quick recap on what exactly these researchers did. Josef Rauschecker and graduate student Brannon Green from Georgetown University devised an experiment in which participants listened to atonal music (generated by a computer) while in the scanner. Participants first heard a single musical phrase made up of several notes, after which they heard the same phrase of notes but this time, with a new phrase added on at the end. This pattern continued until the entire musical sequence was played in full. You can imagine, then, that at the end of the sequence, the first musical phrase would have been played many times over while the last phrase of the sequence would have only been played once. The purpose of the study? To see precisely what was happening as the brain learned a new musical sequence, of course!

What Rauschecker and Green found from this experiment was what landed them a spot in the News section of the KOSU Radio website. The brain scans showed that motor areas became active when the participants heard something new (i.e., the newest phrase of musical notes played). On the other hand, these same motor areas showed significantly less activation when participants heard more familiar notes. It was during these familiar sequences that activity increased in areas involved in hearing, which suggests that these hearing areas can remember small chunks of notes, but that the motor system is what compiles these chunks of notes into a correct, coherent order. Now some of you may be slightly baffled, thinking, "But motor areas? Really?! I thought motor areas were for movement, not for hearing music!". It actually makes sense, if you think about it this way. Just as in dance, when your motor system is programmed to work with your muscles in a particular sequence, so too your motor system is activated when you hear a new piece of music. Your motor system is responsible for sequencing the notes you hear and programming them into your memory, which explains why you see activity in the motor areas when new music is played. Rauschecker has even gone as far as finding evidence that the motor system can help retrieve chunks of forgotten musical notes - something all musicians (including myself) have surely experienced at least once in their musical career.

So next time you hear a new song on the radio, do a little dance - chances are, you'll be more likely to remember that song the next time you hear it (which should be within the next hour or so, if you listen to the same radio stations I do!). 

S

November 26, 2012

Sleep Deprivation and the Stroop Task

I've decided to start this post off with a small test. See how fast you can identify the font colour of the words below ... and ... GO!


So - how did you do? Did you find it difficult to ignore what the word said and focus instead on the actual colour of the font? If you did, don't worry - it is completely normal to find it difficult to inhibit your automatic response to read the word. What you just did is a common task known as the Stroop task, devised by John Ridley Stroop in 1935. The basis of this task involves the use of incongruent stimuli (i.e., using the name of a colour that is printed in a colour not denoted by the name) to cause what is fondly known as the Stroop effect - where naming the font colour takes longer (measured by reaction time, or RT) and is more prone to errors than when the font colour matches the written word itself. Since Stroop's initial publication on the Stroop effect (see: Studies of interference in serial verbal reactions by J.R. Stroop, 1935), the Stroop task has been widely replicated and is currently one of the most commonly known and used tasks in research and clinical practice worldwide. And so from this brief background on the Stroop task, I now segue into a recent paper published in Brain and Cognition in 2011 - a paper that not only involves said Stroop task, but also incorporates an (indirect) aspect of my Masters thesis: sleep deprivation.


Cain, S.W., Silva, E.J., Chang, A.M., Ronda, J.M. and Duffy, J.F. (2011) One night of sleep deprivation affects reaction time, but not interference or facilitation in a Stroop task. Brain and Cognition 76: 37-42.

Goals of the study?
In this study, Cain and colleagues aimed to study the effects of prolonged wakefulness on Stroop task performance by placing thirty healthy participants in a 40-hour "constant routine" (CR) protocol, during which the participants remained awake in constant conditions and performed a Stroop task every two hours. Several studies prior to this have examined the performance of the Stroop task under acute sleep deprivation conditions, but the results of these studies were not able to differentiate between the general effects of sleep deprivation on performance and the effects specifically related to Stroop interference. Moreover, these previous studies were unable to determine whether the sleep loss-related decrements in Stroop task performance were due to slower RTs or whether executive function (and the prefrontal cortex) were also affected by sleep deprivation.

Hypothesis?
Cain and his research team hypothesized that sleep deprivation would affect RT and error rate but not interference in the Stroop task. This would indicate that attention and vigilance may be more sensitive to sleep loss than the executive functions involved in Stroop interference.

Methodology?
- Three 24-hour baseline days (16 hours of wakefulness and 8 hours of bed rest in the dark)
- 40-hour CR (see above)
- Non-24-hour sleep/wake cycle (designed to determine the period of their circadian timing system)
Interference = mean RTs of incongruent trials - mean RTs of neutral trials (reflects additional time needed to respond when reading the word interferes with responding to the colour)
Facilitation = mean RTs of congruent trials - mean RTs of neutral trials (reflects the increased speed of reaction when colour and word matched)

Results?
There were several significant results that came out of this study. I will list them in the order that they were presented in the paper.

1. There was a significant main effect of time awake on RT, such that RT slowed with increasing time awake.
2. There was a significant main effect of trial type on RT, such that incongruent trials showed the slowest RT, congruent trials showed the fastest RT and neutral trials showed intermediate RTs.
3. There was a significant main effect of time awake on the error rate of responses, such that there were more errors with increasing time awake.
4. There was a significant main effect of trial type on error rate, such that the incongruent trials had the most errors made, the congruent trials had the fewest errors made, and the neutral trials had an intermediate number of errors made.
5. For RT, significant differences between incongruent and neutral trials were observed at 6, 8, 12, 14, 16, 22, 34, 36 and 38 hours awake.

There were also several non-significant results that came out of this study. Again, I will list them in the order that they were presented in the paper.

1. There was no significant interaction between the main effects of time awake and trial type on RT.
2. There was no significant interaction between the main effects of time awake and trial type on error rates of responses.
3. There was no significant main effect of time awake on indexes of interference or facilitation.

What do these results mean?
An interesting pattern of performance was found when analyzing the results (and this is what REALLY interested me!).
Performance on all three trial types was stable across the first 14-16 hours of CR, which corresponded to the usual waking hours of the participants. For the next 10-12 hours following this period (which corresponded to the usual sleeping hours of the participants), both RTs and error rates showed increases, suggesting that there was no apparent speed/accuracy trade-off. However, RTs and error rates on all three trial types stabilized after about 24 hours awake, and (fascinatingly) rebounded slightly between hours 28 and 36! This pattern of performance rebound in the morning after a night awake may reflect an underlying circadian rhythm in sleep-wake propensity, as studies using other types of cognitive performance have demonstrated a similar pattern.
Both indexes of interference and facilitation used were not significantly affected by sleep deprivation. Therefore, the executive function of inhibiting the prepotent response of responding to the word did not appear to be very sensitive to one night of sleep loss. It may be, however, that one night of sleep loss was merely insufficient to affect these processes. Furthermore, these findings may have arisen from a problem known as "task impurity", in which a particular task may involve the interaction of executive and non-executive components, both of which influence performance. It is thus posited that sleep loss may affect overall performance on the task via either one or more of these components.

Conclusions?
As expected, RTs were slowest for incongruent trials, fastest for congruent trials and intermediate for neutral trials. Also expected were the errors made during incongruent (most errors), congruent (least errors) and neutral trials (intermediate errors). It was thus concluded that under constant environmental and behavioural conditions, one night of sleep loss slows down RT and increases error rates in Stroop performance, but appears to have no significant impact on Stroop interference or facilitation in healthy, young individuals.


So now that my scientific rambles are all out there for you to read, the most important question is: what is the importance of all of this? I mean, it's not every day that you'd be kept awake for 40 hours in a room with constant conditions and told to perform the Stroop task every two hours, right?

... And to that I say, of course this study is important! For one, it gives me some background as to what to expect during my data collection and analyses. Mind you, my participants won't be forced to stay awake, but sleep deprivation will most definitely be a side effect experienced by the experimental group. Moreover, although no interference effects were found in this study, my study may show otherwise as my participants may suffer from days of disrupted sleep. I am therefore very much looking forward to comparing and contrasting my findings to those presented in this paper. Lastly and most importantly (for you readers out there, wherever you may be), this study gives you an idea of the effects acute sleep deprivation has on your mental and physiological processes. Though you may not consciously feel impaired, this study shows that your inhibition processes, for one, are definitely taking a hit. So the next time you're debating whether or not to pull an all-nighter to finish your 50% essay, think otherwise!

And with that final piece of advice, I'm signing off. I'm headed to the scanner to help scan Ken Swift tonight, a world-famous, highly influential B-boy and an honourary guest at York University's own 3T scanner. Updates on my meet and greet with Ken Swift a.k.a. "The Epitome of a B-Boy" to come!

S

November 20, 2012

Midnight Madness

Before I begin, I feel it necessary to pre-empt this post with the following message:

Warning: Do not be fooled by the title! If you continue reading, you are, in fact, not reading about the insanely cheap yet awesome deals that stores put out, but about the (sometimes random) musings of a graduate student into the wee hours of the night .........

It's 3:00am and I find myself wide awake, in bed, with no hope of falling asleep anytime soon. Odd that this should happen on a Monday night, and even odder because I never have trouble falling asleep! Trust me, I am definitely one of those evolutionary anomalies that never outgrew the hibernating a.k.a. sleeping-for-20-hours-a-day phase. Lucky for me, I've grown up in the "technology at your fingertips" generation, so here I am hoping that writing this blog post will settle my mind some and help me get to sleep.

Monday, November 19th, 2012 actually marks quite a momentous occasion for me. I'm probably building this up to way more than it actually is, and most (if not all) of you reading this have probably gone through this at least once, if not more, but ...

TODAY I GOT SCANNED!


Now before you start thinking I've gone a little off my rocker, just give me a chance and hear me out. After months upon months of reading numerous fMRI studies, learning how to analyze the raw data, taking a course on the physics behind fMRI, completing multiple level 1 and level 2 training sessions AND watching several others get scanned, it was finally my turn! I was so excited that I could barely sleep on Sunday night - I was awake every hour on the hour - even though I had told myself that I needed a good night's sleep so that I wouldn't fall asleep in the scanner. [Spoiler: I didn't fall asleep, thanks to the anticipation that had been built up for months on end.] For all of you out there that haven't had the opportunity to be scanned but would like to know what it's like, here's where it gets interesting (and for the rest, read on anyways!).

My first observation was that things were much more lackadaisical than I had expected. If I learned anything from the (few hours of) MRI training that I had, it was to be thorough from beginning to end. Be it with screening, set-up or even explanations to participants, it is crucial to make sure you cover your bases! I guess with this scan being for the purpose of our class only, some things were less important than others. Either way I was comfortable going in, and at the end of the day that's what really matters.

Prepping to go into the scanner was a breeze - I had gone in and out of the magnet room so many times before. Reality didn't finally hit me until I was actually being sent into the Bohr, and at that point all I could think was "holy [bleep]!!". The biggest issue that people run into when inside the MRI is an overwhelming feeling of claustrophobia. Mind you, I am by no means claustrophobic, but some weird situations do set me off (i.e., sitting in the window seat of a bus/plane with someone sitting directly beside me and no immediate escape/exit route ... don't ask). Once inside the scanner, I felt that same feeling slowly creeping over my body, but shortly after Keith's voice came over the intercom and I felt much more at ease. I now know how important it is to immediately establish communication with your participant inside the scanner - it could mean the difference between a successful scan and a withdrawal from your study!

Shortly after the anatomical began, I noticed two things: first, that my vestibular system followed Keith out the door, and second, that my senses were most definitely heightened. With little to no visual periphery, I felt as if I was moving when in reality, I was stationary with no place to go. This quickly resolved itself after I closed my eyes for a few seconds. During the entire 45 minutes of scanning, however, I could feel my body tense and stay tensed. I had to constantly remind myself to relax - beginning at my shoulders all the way down to my toes - only to find that, when I got to my toes, my shoulders were tensed up again! I chalked this up to my way of keeping my head from moving - after all, the instructions "try your best not to move your head" is forever imprinted in my brain! Moreover, I felt as if my breathing was shallow and staggered, something that I could not ignore no matter how hard I tried. What was most unbearable, though, was the fact that I fell into a vicious "I need to swallow" "but I can't swallow because it will create an artifact!" cycle. All the information from the papers I had read and from the classes I had attended - all of that built up and released itself into my working memory as soon as the functional runs began. The more I wanted to swallow, the more I would tell myself not to because I wanted to be an ideal subject with hardly any motion artifacts; the more I thought about being an ideal subject, the more I wanted to swallow; the more I wanted to swallow, the more information I recalled on what not to do when being scanned. This cycle was almost the death of me - you have no idea how close I came to squeezing that emergency ball! And it's a good thing I didn't because the last part of the scan was by FAR the best part. During diffusion tensor imaging (DTI - a technique to track the movement of water particles to and from brain regions via neurons), the entire bed and head coil vibrates with quite some intensity. I had to stifle a laugh at the beginning because I couldn't believe how much it resembled a massage chair! DTI was a welcome reprieve after being all tense and stressed out, so if there's one aspect of today's scan that I would like to experience again, it would be that. I'd also like to do a resting state scan at some point, but I'm sure there will be time for that in the future.

So with this detailed recap on ... dashboard(?) ... I am finally tired enough to head to bed. I definitely did not expect this post to turn out as long as it did, but for those of you who've stuck by to the end I hope you'll take away with you a tidbit of knowledge. Overall? It was a great experience. I cannot wait to log some more hours inside the scanner - hopefully as a research participant next time!

*Pictures of my brain to come!*

S

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UPDATE:

As promised, here are some pictures of my brain! I am extremely fascinated by them and cannot stop staring ... is that normal?! Either way, they have totally made my day!!!




SO. COOL!!!

November 10, 2012

Blog Time.


Well well well. Look what we have here!

I know I'm a little late getting into this whole blogging business (as I usually am with all internet fads), but after speaking with my supervisor Joe and my friend Paula about the benefits of having a blog, I decided I'd try my hand at blogging.

I mean, there's no harm in starting my own blog space, right?

... Except for the fact that I now have ANOTHER means of procrastination! Which really COULD do some serious harm, as I don't have the biggest attention span AND I tend to wander off into my thoughts sometimes ...

Nonetheless, I'll try to update my blog as often as I can. So if you're interested in circadian rhythms, neuroscience or science in general (c'mon, who doesn't like science!), follow me as I blog through my 22nd year of life as an MSc2 student!

Cheers,
S

My Sunshine

Ps. Here is a picture of the love of my life. Just thought I'd share him with the world, and give everyone  a bit of Sunshine on this gorgeous fall day!