Mapping the Brain in Decline

Alzheimer's is a nasty disease, resulting in progressive, permanent, neurological deterioration, leading eventually to dementia - and the loss of the unique you that existed before the disease - even if your heart remains strong and your body robust. The causes and progression of Alzheimer's are not well understood.

One of the reasons research in Alzheimer's has been hampered is because of a lack of a reliable method to diagnose it. Alzheimer's is diagnosed with a constellation of symptoms, including memory loss, mood swings, aggression, symptoms of mental decline, and, most notably, amyloid plaques on the brain. Amyloid plaques - bunches of protein fibers in the gray matter of the brain - are necessary for the diagnosis of Alzheimer's, but testing for their presence was not possible until after the person died and their brain could be examined in an autopsy.

A new study shows great promise in the detection of these plaques, however. In this research, radioactive dye is injected into the brain.  This "lights up" the plaques in brain scans, and therefore makes them viewable. This is important for a variety of reasons.

Brain scans that showed plaque could help with some fundamental questions — who has or is getting Alzheimer’s, whether the disease ever stops or slows down on its own and even whether plaque is the main culprit causing brain cell death.

Being able to accurately diagnose Alzheimer's would be pivotal in the development of means by which to combat its effects. For example, we might be able to identify people who were in the process of getting Alzheimer's - a breakthrough that could provide help to people before declines begin. It would also give us more information about whether or not new drugs developed to treat it were working.

But my favorite part of this emerging research? The creativity and tenacity of the scientists who conducted the study. The FDA insisted that proof be supplied that the amyloid plaques being detected in the brain scans are the same as the ones that are identified in the brains of dead Alheimer's patients. How can a researcher collect this information in a reasonable amount of time, given that patients with Alzheimer's often survive for decades after the initial diagnosis is made? Well, the researchers came up with a solution to this - conduct research on participants in a hospice, close to death and nearing their final stop in the march of life. While some criticized this initially as being unethical or demeaning to potential participants, the research was allowed to proceed (and from accounts, people were glad to participate). And the research worked. And now, because of this, a new technique to monitor a terrible disease is within our sights.

Science is not pure. It is shaped and molded by pragmatic and ethical constraints. The trick is not just knowing what to study, but how to go about doing so in a way that is both scientifically valid, ethically justifiable, and practically possible. Kudos to this research team for their ingenuity.

Extra Credit: Undergraduate Assessment

Give your opinions about instructors, course offerings and advising.  And EXTRA CREDIT.  2 points to be specific.

Undergraduate Assessment Survey

Theory Shmeary

So you know how sometimes people complain about theories being just a theory?  You know, as opposed to a law?  Ever wondered what that really meant?

Theories are organized sets of hypotheses, organized sets of whys laid out in an attempt to understand some group of facts that have been observed. In scientific terms at least, theories have stronger support and explanatory power than laws.  Good theories are testable, they can be shown to be wrong, or if we are lucky good and careful scientists, perhaps on the road to right. So theory schmeary and all that.

And, in scientific terms at least, "law" doesn't mean quite the same thing as in everyday speech.  In everyday speech, laws are rules we are supposed to obey - things we have to do but sometimes don't or things we get in trouble for doing.  By contrast, in scientific terminology laws are descriptions of things that happen.  They are primarily observatory in nature, meaning they tell us what happens under a certain set of circumstances.  Apple rolls off head, apple falls.  It tells us the what of what happened.  But - and here's a crucial part - it doesn't tell us the why, and that's because we generally don't understand why they happened, we just know that they do. So in terms of evidence and explanatory power, theories are the better bet.

However, in the spirit of internet memes, let me pass on for you a PSA recently forwarded to me about a law you should follow.

Because seatbelts?  Not just a good idea.  The LAW.

Research Internship at OHSU

Research Intern

Oregon Health Science University, Sleep and Mood Disorders Laboratory http://www.ohsu.edu/sleeplab
The Sleep and Mood Disorders Laboratory at OHSU conducts studies on human circadian rhythm disorders, including experiments testing the effectiveness of properly-timed doses of melatonin to treat such disorders in totally blind people.  Other research studies include work in circadian misalignment in non-seasonal major depression and the genetics of morning and evening types.

We are currently looking for one or more psychology, biology or pre-med students to assist in various levels of the research process, including data entry and analysis, literature searches, transcribing sleep diaries, filing journal articles, and preparing materials for research subjects. This position may also require interaction with research subjects, including recruitment and screening.  Good communication skills and attention to detail are required. Knowledge of computer application software (Word, Excel) is preferred.  This position is an unpaid internship.  To apply for this position, please submit cover letter and resume to Amber Laurie at sleeplab@ohsu.edusleeplab@ohsu.edu>.

Money for Participating in a Research Study!

Hi all,
Robert Roesser, of the psychology department here at Portland State, is recruiting students for a study on contemplative education.  His website is here, his blog is here, and the recruitment information is here.


                  

What's your romantic attachment style?

In line with what I promised in class yesterday, here's a short quiz to measure your romantic attachment style.

This particular questionnaire will break down your beliefs about romantic relationships in two dimensions - anxiety and avoidance.  Anxiety relates to your feelings of self-worth and whether or not you are worthy of the love of others.  Avoidance relates to your desire for closeness in a relationship.

It's a kid's world.

A link to Scientific American Frontiers: It's a kid's world. This has the magical events video, some fun segments (which we won't be covering) on motor development, and some segments on Theory of Mind and Language which we will watch later in the quarter.

The ever increasing pace of the world.

The New York Times just printed an interesting article on the ways in which technology - and the ever increasing pace of change that comes concordant with that - might be affecting our children.  This is interesting in and of itself.  We might wonder how our children's malleable young minds are shaped by the cacophony of media they are exposed to, how their understanding of the world might shift as they inhabit more and more time in electronic and online activities, and how the absence of many of the influences of the past might shape their development. Already we see some differences - younger generations expect information immediately, seem to have less privacy concerns and are better at multitasking than older adults.  These changes may not be all good.  For example, the increase in multitasking could potentially have negative effects on the ability to focus on materials for longer periods of time - such as is needed in schooling.

But there's another issue that has to do more with the increasing pace of change rather than the actual experiences themselves.  We'll be talking about research methods tomorrow, and we'll be discussing types of studies that utilize what are called "developmental designs".  I know you'll be excited to learn about won't really have a choice but to listen to me talk about cross-sectional, longitudinal and sequential designs.  All three of these are ways of looking at change over time.  Cross-sectional designs focus on looking at a group of people of slightly different ages at one point in time, with the implicit assumption often being that by looking at the differently aged people, you can figure out what changes in development due to the effects of age. Longitudinal designs focus on a single group of people over time with the implicit assumption often being that that particular group of people should be illustrative of how development generally occurs in people outside of your specific study sample.  We'll talk about why these assumptions are not always correct, but for now I will just note that sequential designs are an attempt to pin down the actual differences between age effects, cohort effects and time of measurement effects by basically combining longitudinal and cross-sectional designs.

But what happens when change gets really fast?

Researchers are exploring this notion too. They theorize that the ever-accelerating pace of technological change may be minting a series of mini-generation gaps, with each group of children uniquely influenced by the tech tools available in their formative stages of development.

“People two, three or four years apart are having completely different experiences with technology,” said Lee Rainie, director of the Pew Research Center’s Internet and American Life Project. “College students scratch their heads at what their high school siblings are doing, and they scratch their heads at their younger siblings. It has sped up generational differences.”

 Already, we have to be careful in research to attend to which of our findings are driven by actual developmental change and not by cohort.  What happens when cohorts shrink in size?

Consumption

I mentioned today I love coffee.  I really really do.  I also mentioned that coffee, or presumably the caffeine in coffee, has been demonstrated to have a positive effect on cognitive performance.  I like this data.  A lot.

I also like this recent article.  It's an overview of some of the effects that have been found related to coffee consumption.

This month alone, an analysis in the Archives of Internal Medicine found that people who drink three to four cups of java a day are 25% less likely to develop Type 2 diabetes than those who drink fewer than two cups. And a study presented at an American Association for Cancer Research meeting found that men who drink at least six cups a day have a 60% lower risk of developing advanced prostate cancer than those who didn't drink any

And it gets BETTER even.

Earlier studies also linked coffee consumption with a lower risk of getting colon, mouth, throat, esophageal and endometrial cancers. People who drink coffee are also less likely to have cavities, gallstones, cirrhosis of the liver, Parkinson's disease and Alzheimer's disease, or to commit suicide, studies have found. Last year, researchers at Harvard University and the University of Madrid assessed data on more than 100,000 people over 20 years and concluded that the more coffee they drank, the less likely they were to die during that period from any cause.

Seriously - that's music to my ears.

But...I also talked today about how one of the reasons that every psychology course has a section on research methods, and one of the reasons that I go on and on and on until you fall asleep spend so much time and energy trying to hammer home research methods is that understanding some of the details and rules about how science is conducted helps us become better consumers of science.  Just because we find a relationship between two variables (i.e. a correlation) doesn't necessarily imply a causal relationship, even it it's something we really really want to believe.

The WSJ article actually does a relatively good job pointing out some of the complications with the rosy view of coffee presented above.  For example, they point out that while certainly those beneficial effects have been noted, negative effects for coffee consumption have also been found in other research.

But those studies come on the heels of older ones showing that coffee—particularly the caffeine it contains—raises blood pressure, heart rate and levels of homocysteine, an amino acid in blood that is associated with stroke and heart disease. Pregnant women who drink two or more cups of coffee a day have a higher rate of miscarriages and lower birth-weight babies; caffeine has also been linked to benign breast lumps and bone loss in elderly women. And, as many people can attest, coffee can also aggravate anxiety, irritability, heartburn and sleeplessness, which brings its own set of problems, including a higher risk of obesity. 

Moreover, as they point out, research on coffee consumption is plagued by many of the same methodological concerns common to most research focusing on lifestyle issues.  For reasons of both pragmatics and ethics, most studies such as the ones cited above involve observational designs.  In other words, people report on their consumption.  As such, there may be something different about regular coffee drinkers than those who abstain, or people's memories may be faulty or incorrect. And lab studies which do control for these factors can be critiqued on the grounds that they are not ecologically valid.  What happens in the lab may not necessarily mirror what happens in real  life.

The authors of the article conclude that while there are some indications that coffee can be a healthy drink, there is not enough evidence to suggest that non-coffee drinkers take up the habit, and that certain groups (e.g. pregnant women, people with high blood pressure) should consider reducing their intake.

As for me?  I'll stick with my caffeine habit.  After all it makes the morning headache go away just tastes so darned good in the morning!

So how do you really feel about race?

So we talked a bit about race and stereotypes recently in class.  I mentioned that we all know what the stereotypes are, but we differ on how much we endorse them.  In other words, the content of all our stereotypes is very similar, but our endorsement of their accuracy varies wildly.

But, even if we disagree with a particular stereotype, can it still affect us? Research shows that it might.  There are what are called implicit stereotypes that operate outside of conscious awareness, but can still affect us.  A particularly clever methodology has been developed by Greenwald to test out our implicit biases - the underlying beliefs and associations that we might have and not even be aware of.  This methodology was originally developed to examine implicit attitudes directed towards African-Americans, but has since been extended to a wide variety of areas in which people standardly discriminate against each other.

I think this is research that provides a good model of what research should be; about important things, methodologically sound, based on prior knowledge, and ultimately, creative in its development and execution.  What Greenwald's test does is use our reaction time as a measure of what things tend to go together with what other things in our brains.  In other words, how quickly we can perform certain tasks is a clue about the structure of our concepts.

What happens is you are asked to make a decision about a series of pictures.  A photo of a face pops up - if the photo is of the face of an African American you are asked to indicate this by pressing the "e" button, and if it's the face of a European, you are to press the "i" button.  After this training session, the faces are replaced with words.  If a "good" word (e.g. love, glorious) pops up you press the "e", and if a "bad" word (e.g. war, hate) pops up you are to press the "i" button.  Then, after this second training session, you are asked to do both tasks at once.  Either a word or a face will pop up, and you have to categorize them correctly. This process is repeated, although the pairs are varied (i.e. first you might be asked to categorize (AA/good, EA/bad), then (AA/bad, EA/good)).

The critical dependent variables are your reaction times and mistakes.  If you can respond more quickly when the "good" words and European American faces are paired, then this suggests that you have an automatic association of European American and good.  In other words, you are quicker to respond to that particular pairing because it fits with your own unconscious attitudes.  The task and your beliefs match. On the other hand, if they don't, your performance will be slower.  So, we can get a sense of how strong your biases are by how much you are sped up or slowed down in your responses.  Analogously, your mistakes will tend to be in one direction.  If you make very few categorization mistakes for the (EA/good, AA/bad) trials, but many mistakes for the (AA/good, EA/bad) trials, then that suggests that the second pairing is harder for you because it doesn't match your internal associations.

As it turns out, most everyone, even people who are low in prejudice, tend to have biases.  In fact, when the IAT was first developed, many people became upset at discovering that they had been harboring less-than-nice beliefs (that's in fact, now in part of the consent form so that people aren't surprised to find out unsavory truths about themselves).  While some people argue about what these findings might mean, Greenwald and his associates make the argument that without due diligence on our part, implicit biases can indeed color our actions and impact explicit, conscious behavior.

Try the IAT for yourself.