- ARCHIVE / AUTHOR ARCHIVE
Marijuana and Divergent Thinking [The Frontal Cortex]
In response to my post on the effects of mood on cognition, which also referenced the possibilities of self-medicating ourselves into the ideal mood, Andrew Sullivan offered up the following anecdote:
I was talking with a fine artist the other day and he was telling me how blocked he was on a piece, and how he then smoked some pot and everything came together.
It unleashed what he wanted to express, by suppressing the analytic portion of his mind that was inhibiting him. I know this is the bleeding obvious to anyone who has a brain and an ounce of human experience but it is a truth we are somehow circumscribed from uttering in public.
There's a reason why jazz would be impossible without weed.
A new paper published in Psychiatry Research sheds some light on this phenomenon, or why smoking weed seems to unleash a stream of loose associations. The study looked at a phenomenon called semantic priming, in which the activation of one word allows us to react more quickly to related words. For instance, the word "dog" might lead to increased reaction times for "wolf," "pet" and "Lassie," but won't alter how quickly we react to "chair".
Interestingly, marijuana seems to induce a state of hyper-priming, in which the reach of semantic priming extends outwards to distantly related concepts. As a result, we hear "dog" and think of nouns that, in more sober circumstances, would seem to have nothing in common.
Here's Vaughan Bell, lucid as always:
The effect [hyper-priming] has been reported, albeit inconsistently, in people with schizophrenia and some have suggested it might explain why affected people can sometimes make false or unlikely connections or have disjointed thoughts.
As cannabis has been linked to a slight increased risk for psychosis, and certainly causes smokers to have freewheeling thoughts, the researchers decided to test whether stoned participants would show the 'hyper-priming' effect.
Volunteers who were under the influence of cannabis showed a definite 'hyper-priming' tendency where distant concepts were reacted to more quickly. Interestingly, they also showed some of this tendency when straight and sober .
Obviously, you don't want too much hyper-priming, or else everything seems connected; the web of associations becomes a source of delusions. But for many creative tasks it's important to cultivate an expansive associative net, or what psychologists refer to as a "flat associative hierarchy".
Interestingly, there's some speculative evidence that such distant intellectual connections are most likely to be generated in the right hemisphere. There is, for instance, that research on moments of insight that I've written about before. But there's also some interesting data from patients with selective hemispheric damage. When people suffer an injury to their left hemisphere, the side-effects are obvious: they typically lose the ability to speak in coherent sentences, or suffer other dramatic language deficits. They neglect relevant details, miss appointments and struggle to get dressed. People with right hemisphere damage, in contrast, tend to experience much more subtle symptoms, such as an inability to "get" a joke or perceive sarcasm or enjoy a poem. All of these skills require a coarse-grained kind of cognition, an ability to look past the details and see the remote associations.
And this returns us to madness. Several studies have found that people with extremely mild forms of schizophrenia - they're often referred to as "schizotypal"-- perform above average when solving various lab tasks used to measure creativity. What explains this anomaly? Interestingly, schizotypal subjects also have markedly enhanced right hemisphere function, and are more likely to rely on this hemisphere during normal cognitive processing.
Last speculative point: marijuana also enhances brain activity (at least as measured indirectly by cerebral blood flow) in the right hemisphere. The drug, in other words, doesn't just suppress our focus or obliterate our ability to pay attention. Instead, it seems to change the very nature of what we pay attention to, flattening out our hierarchy of associations.
If you're interested in an overview of our distinct hemispheric talents - a fascinating subject that has been obscured by too much bad pop science - I'd recommend this book.
Read the comments on this post...Immune response to brain infection may trigger Alzheimer’s [Neurophilosophy]
ALZHEIMER'S Disease is the most common form of dementia, affecting an estimated 30 million people worldwide. The cause of the condition is unknown, but the prime suspect is amyloid-beta (Aβ), a 42-amino acid peptide which accumulates within neurons to form insoluble structures called senile plaques that are thought to be toxic. Aβ is synthesized in all neurons; it is associated with the cell membrane, and is thought to be involved in cell-to-cell signalling, but its exact role has eluded researchers.
A new study published in the open access journal PLoS One now shows that Aβ is a potent antibiotic that can prevent the growth of a number of disease-causing microbes. The study provides the first evidence of a normal role for Aβ, and also raises the intriguing possibility that Alzheimer's Disease occurs as a result of the immune system's response to infection. The findings could make researchers re-think Alzheimer's, and have implications for how the condition is treated.
Read the rest of this post... | Read the comments on this post...Scientia Pro Publica — It’s Almost Here! [Living the Scientific Life (Scientist, Interrupted)]
Image: wemidji (Jacques Marcoux).
Nam et ipsa scientia potestas est (And thus knowledge itself is power)
-- Sir Francis Bacon.
Read the rest of this post... | Read the comments on this post...
The next edition of Scientia Pro Publica (Science for the People) is less than two weeks away and it is seeking submissions! Can you help by sending URLs for well-written science, medicine, and nature blog essays to me?
Welcome the newest SciBlings! [A Blog Around The Clock]
Go say Hello to Travis Saunders and Peter Janiszewski, the newest bloggers on the Scienceblogs.com network at Obesity Panacea.
They cover health, physiology, nutrition and exercise - something we did not have here on the network before, at least not in such a concentrated form. Check out the archives of their old blog and then bookmark the new Obesity Panacea.
Read the comments on this post...Pay it forward? Cooperative behaviour spreads through a group, but so does cheating [Not Exactly Rocket Science]
Ever wonder if acts of kindness or malice really do ripple outwards? If you give up a seat on a train to a stranger, do they go onto "pay it forward" to others? Likewise, if you steal someone's seat, does the bad mood you engender topple over to other people like a set of malicious dominoes? We'd all probably assume that the answers to both questions were yes, but James Fowler and Nicholas Christakis think they have found experimental evidence for the contagious nature of cooperation and cheating.
The duo analysed data from an earlier psychological experiment by Ernst Fehr and Simon Gachter, where groups of four volunteers had to decide how much money to put in a public pot. For every unit they chipped in, each member would get 0.4 back. So any donations represent a loss to the donor, but a gain to the group as a whole. The best way for the group to benefit would be for everyone to put in all their money, but each individual player could do even better by putting in nothing and feeding off their peers' generosity.
This "public goods game" went on for six rounds. At the end of each one, the players were told what their other comrades did, although everyone's identities were kept secret. The groups were shuffled between rounds so that players never played with each other more than once.
Fowler and Christakis found that the volunteers' later moves were influenced by the behaviour of their fellow players. Each act of generosity by an individual influenced the other three players to also give more money themselves, and each of them influenced the people they played with later. One act became three, which became nine. Likewise, players who experienced stingy strategies were more likely to be stingy themselves.
Even though the groups swapped every time, the contagious nature of generous or miserly actions carried on for at least three degrees of separation. You can see an example of one such cascade in the diagram below. Eleni contributes some money to the public pot and her fellow player, Lucas, benefits (one degree). In the next round, Lucas himself offers money for the good of the group, which benefits Erika (two degrees), who gives more when paired with Jay in her next game (three degrees). Meanwhile, the effects of Eleni's initial charity continue to spread throughout the players as Lucas and Erika persist in their cooperation in later rounds.
Read the rest of this post... | Read the comments on this post...
Marriage [The Frontal Cortex]
One of the hazards of writing a book on decision-making is getting questions about decisions that are far beyond the purview of science (or, at the very least, way beyond my pay grade). Here, for instance, is a question that often arrives in my inbox, or gets shouted out during talks:
"How should we make decisions about whom to marry? If the brain is so smart, why do half of all marriages end in divorce?"
Needless to say, there is no simple answer to this question. (And if I had a half-way decent answer, I'd be writing a book on marriage.) But I've been recently been reading some interesting research on close, interpersonal relationships (much of it by Ellen Berscheid, at the University of Minnesota) and I'm mostly convinced that there's a fundamental mismatch between the emotional state we expect to feel for a potential spouse - we want to "fall wildly in love," experiencing that ecstatic stew of passion, desire, altruism, jealousy, etc - and the emotional state that actually determines a successful marriage over time. Berscheid defines this more important emotion as "companionate love" or "the affection we feel for those with whom our lives are deeply intertwined." Jonathan Haidt, a social psychologist at the University of Virginia, compares this steady emotion which grows over time to its unsteady (but sexier and more cinematic) precursor: "If the metaphor for passionate love is fire, the metaphor for companionate love is vines growing, intertwining, and gradually binding two people together."
What's wrong with seeking passion? Don't we need to experience that dopaminergic surge of early love, in which the entire universe has been reduced to a single person? ("It is the east, and Juliet is the sun.") The only problem with this romantic myth is that passion is temporary. It inevitably decays with time. This is not a knock against passion - this is a basic fact of our nervous system. We adapt to our pleasures; we habituate to delight. In other words, the same thing happens to passionate love that happens to Christmas presents. We're so impossibly happy and then, within a matter of days or weeks or months, we take it all for granted.
I can't help but think that Shakespeare was trying to warn us about the fickleness of passionate love even as he was inventing its literary template. Romeo and Juliet, after all, begins with Romeo in a disconsolate funk. But he's not upset about Juliet. He hasn't even met Juliet. He's miserable over Rosaline. And so, while the rest of the tragedy is an ode to young lovers and impossible passions, Shakespeare has prefaced the action with a warning: passion is erratic. The same randy Romeo who compares you to the sun was in love with someone else last night.
What makes this mismatch even more dangerous is our tendency to confuse physical attractiveness with personal goodness. In a classic 1972 paper, "What is beautiful is good," Berscheid and colleagues demonstrated that we instinctively believe that prettier people "have more socially desirable personality traits" and "lead better lives". Furthermore, this phenomenon works in both directions, so that people who have been "prejudged" to be more or less physically attractive, but don't know they've been judged that way, still behave in a more "friendly, likeable and sociable manner". This suggests that our emphasis on attractiveness, lust and beauty - these are the variables that we associate with passionate love - can actually distort our perception of more important personality variables. Because we'll habituate to those hips, and that sexy smile won't be sexy forever. And then we'll no longer confuse beauty with goodness, or believe that our attractive boyfriend is also really nice.
The point is not that passionate love isn't an important signal. It surely is - that rush of dopamine is trying to tell us something. But a successful marriage has to endure long past the peak of passion. It has survive the rigors of adaptation and intimacy, which are features of romantic relationships that don't get valorized in Hollywood, Bollywood or Shakespeare.
Read the comments on this post...Praying Mantis Attacks Hummingbird [Living the Scientific Life (Scientist, Interrupted)]
tags: Praying Mantis, Preying Mantis, mantid, insects, birds, hummingbirds, offbeat, predation, predatory behavior, nature, streaming video
Read the rest of this post... | Read the comments on this post...
Sandy Lizotte, the Ventura Hummingbird Lady, captures a rare and remarkable moment where a praying mantis was waiting patiently at a hummingbird feeder to ambush a hummingbird. As you'll see in this video, the mantid succeeds.
Science with Moxie’s Princess Ojiaku: PLoS Blog Pick of the Month this week, on tour with band next week [Terra Sigillata]
I want to get this quick shout-out for local hero, blogger, musician, and all around too-cool Princess Ojiaku before her band, Pink Flag, plays tonight at 10 pm in Durham, NC, at The Broad Street Cafe. From their website, "They're a regular three girl rhumba dancing on the common ground of a love of early post-punk, riot grrl and top 40 of the 1990s." Their name pays homage to the 1977 album by Wire (that also includes the song "Three Girl Rhumba"). I like these kids, paying proper respect to their elders.Some of you may know Princess from having met her at ScienceOnline2010 in January or from her blog Science With Moxie. One of her recent posts, Music Emotions: Chill Edition, was selected as the PLoS Blog Pick of the Month for her review of, "The Rewarding Aspects of Music Listening Are Related to Degree of Emotional Arousal," by Valorie N. Salimpoor et al. She wrote:
When we get chills or feel intense pleasure when listening to music we enjoy, there is an actual range of bodily responses that go along with that! This seems like common sense, but this is important scientifically because having an actual, quantitative measure of the changes our bodies go through when experiencing good music opens doors to scientists thinking about other questions like, "why is music so unique that it causes actual emotional and physical arousal?"
Usually emotional responses have a definite function, such as joy from eating good food serves to keep us alive, or bonding with friends keeps us happy and connected to our fellow humans. Feeling these emotions helps us by making sure we keep doing the things that are good for our survival and well-being. But music is one of the only things that makes us happy without having a clear beneficial function to our survival as human beings. I think that makes it pretty special and interesting, and that makes me content to consume and play it.
And music she knows as she takes Spring Break away from the lab next week for a short tour with Pink Flag in Wilmington, NC, Baltimore, Philadelphia, and NYC. Check out their MySpace site for dates and locations.One last thing on this multi-talented scientist and musician: Princess was featured in a Wall Street Journal article last September on virtual internships. Typically wired, Princess found out about the internship via Twitter:
Princess Ojiaku, a graduate student studying biology at North Carolina Central University, wants to work in science policy. In July, she began a virtual internship of up to six months with Scientists & Engineers for America in Washington, D.C. She learned about the internship on Twitter, where she was following updates for the nonprofit group, which promotes awareness of science and technology issues to policy makers.
As part of her internship, Ms. Ojiaku spends 15 minutes to an hour each night tracking news articles, ads and poll results for this year's Virginia gubernatorial election, one of the elections the group is following. She posts updates on the group's Web site, including YouTube videos, campaign ads and summaries of the candidates' positions on science-related issues.
Ms. Ojiaku, who is considering being a lawmaker or policy adviser, says the internship has helped her learn about the legislative process and key players in Congress, without driving eight hours round-trip to Washington. "I'm getting an inside view," says the 25-year-old, who juggles the internship with classes and work as a graduate assistant in a university lab.
Damn. I'm tired just reading about everything she's doing.
Have a great show tonight and safe travels on your Northeast tour!
Readers can follow Princess O on Twitter @artfulaction, on her blog Science with Moxie, and at her band's MySpace or ReverbNation sites.
Read the comments on this post...
