Monday, January 11, 2010
Too much information... drowning in a sea of data... swamped by "false positives"
When too much information is collected and when there is no rationale or organizing purpose for collecting the data, bad things can happen. This is the problem of "false positives' that you encounter in elementary statistics that is fundamentally misunderstood by the broader public.
Examples include: mammography in 40-50 year old women with no relevant history. So much counter-terrorism data, including drone data (see article in NYT), is collected that no one can connect the dots. Fmri brain scans collect zillions of bits in data in fishing expeditions with no clear hypotheses
What do all of these examples have in common? Computerized imaging and other systems "overcollect" data and imperil our ability to sort and process MEANINGFUL information. We are drowning in a flood of data....The alternative, as Matt Yglesias puts it, is that we will be "swamped with false positives." Jim Arkedis did an excellent post last week based on his work as an intelligence analyst walking you through how difficult it is is actually “connect the dots” and find a bad guy. The mathematical fact underlying the problem is, as I’ve emphasized, that since only a tiny number of people are al-Qaeda operatives, anything you do is going to be swamped with false positives.
Jim Arkedis did an excellent post last week based on his work as an intelligence analyst walking you through how difficult it is is actually “connect the dots” and find a bad guy. The mathematical fact underlying the problem is, as I’ve emphasized, that since only a tiny number of people are al-Qaeda operatives, anything you do is going to be swamped with false positives.
Standing Meditation in the Chinese Martial Arts
A post on kinaesthetic memory in Tai Chi and the qigong based internal meditative arts. One of the most prominent practices is called Zhan Zhuang. Many many Tai Chi players use this stance to enhance.
There are many descriptions of the benefits of Zhan Zhuang. But none of these descriptions offer a scientific account of why Zhan Zhuang might be beneficial. So, if you practice Zhan Zhuang, or anything like it, I am curious, how would you explain this practice to a scientist who was completely unfamiliar with it, what would you say?
Sunday, January 10, 2010
I'm ambivalent about the neuroscience craze
I'm ambivalent about the neuroscience craze. The brain is a vast territory with new, fascinating discoveries being made every day. But, at the same time, it sometimes feels like, as John Lennon put it, impishly, a fad that is (inappropriately) "bigger than jesus."
Here are some recently published books:
Norman Doidge, The Brain that Changes itself
Andrew Newberg, Why God Won't Go Away
David Rock, Coaching with the Brain in Mind
Rick Hansen, Buddha's Brain
Madeline Van Hecke, The Brain Advantage: Becoming a More Effective Business Leader
Here are some recently published books:
Norman Doidge, The Brain that Changes itself
Andrew Newberg, Why God Won't Go Away
David Rock, Coaching with the Brain in Mind
Rick Hansen, Buddha's Brain
Madeline Van Hecke, The Brain Advantage: Becoming a More Effective Business Leader
New meditation studies
New meditation studies.....
Cahn Delorme and Polich, Occipital gamma activation during Vipassana meditation.
Cognitive Processing, 2009
Long-term Vipassana meditators sat in meditation vs. a control rest (mind-wandering) state for 21 min in a counterbalanced design with spontaneous EEG recorded. Meditation state dynamics were measured with spectral decomposition of the last 6 min of the eyes-closed silent meditation compared to control state. Meditation was associated with a decrease in frontal delta (1–4 Hz) power, especially pronounced in those participants not reporting drowsiness during meditation. Relative increase in frontal theta (4–8 Hz) power was observed during meditation, as well as significantly increased parieto-occipital gamma (35–45 Hz) power, but no other state effects were found for the theta (4–8 Hz), alpha (8–12 Hz), or beta (12–25 Hz) bands. Alpha power was sensitive to condition order, and more experienced meditators exhibited no tendency toward enhanced alpha during meditation relative to the control task. All participants tended to exhibit decreased alpha in association with reported drowsiness. Cross-experimental session occipital gamma power was the greatest in meditators with a daily practice of 10+ years, and the meditation-related gamma power increase was similarly the strongest in such advanced practitioners. The findings suggest that long-term Vipassana meditation contributes to increased occipital gamma power related to long-term meditational expertise and enhanced sensory awareness.
longterm meditators show enhanced occipital gamma (not alpha).
van den Hurk et al, Greater efficiency in attentional processing related to mindfulness meditation. Quarterly Journal of Experimental Psychology, 2009.
In this study, attentional processing in relation to mindfulness meditation was investigated. Since recent studies have suggested that mindfulness meditation may induce improvements in attentional processing, we have tested 20 expert mindfulness meditators in the attention network test. Their performance was compared to that of 20 age- and gender-matched controls. In addition to attentional network analyses, overall attentional processing was analysed by means of efficiency scores (i.e., accuracy controlled for reaction time). Better orienting and executive attention (reflected by smaller differences in either reaction time or error score, respectively) were observed in the mindfulness meditation group. Furthermore, extensive mindfulness meditation appeared to be related to a reduction of the fraction of errors for responses with the same reaction time. These results provide new insights into differences in attentional processing related to mindfulness meditation and suggest the possibility of increasing the efficiency in attentional processing by extensive mental training.
Evan Thompson, Contemplative Neuroscience as an Approach to Volitional Consciousness
This chapter presents a methodological approach to volitional consciousness for cognitive neuroscience based on studying the voluntary self-generation and self-regulation of mental states in meditation. Called contemplative neuroscience, this approach views attention, awareness, and emotion regulation as flexible and trainable skills, and works with experimental participants who have undergone training in contemplative practices designed to hone these skills. Drawing from research on the dynamical neural correlates of contemplative mental states and theories of large-scale neural coordination dynamics, I argue for the importance of global system causation in brain activity and present an “interventionist” approach to intentional causation.
Andrew J. Waters et al,
Associations Between Mindfulness and Implicit Cognition and Self-Reported Affect
Substance Abuse, 2009
Theory suggests that mindful individuals exhibit enhanced attentional processing (e.g., attentional control) and that they maintain a detached perspective to problematic stimuli. For smokers, smoking and affective stimuli are problematic stimuli when they try to quit. In this cross-sectional study, smokers (n = 158) completed 3 modified Stroop tasks (to assess attentional control), 3 Implicit Association Tests (IATs; to assess detached perspective), and a battery of self-report assessments. Degree of mindfulness was negatively associated (P < .05) with self-reported negative affect, perceived stress, and depressive symptom severity, and positively associated (P < .05) with positive affect. Degree of mindfulness was not associated with the ability to disengage attention from smoking or affective stimuli. On the depression IAT, more mindful participants exhibited a more negative IAT effect, suggesting that they may have developed a detached perspective to depression-related stimuli. Theoretical and clinical implications of the data are discussed.
Cahn Delorme and Polich, Occipital gamma activation during Vipassana meditation.
Cognitive Processing, 2009
Long-term Vipassana meditators sat in meditation vs. a control rest (mind-wandering) state for 21 min in a counterbalanced design with spontaneous EEG recorded. Meditation state dynamics were measured with spectral decomposition of the last 6 min of the eyes-closed silent meditation compared to control state. Meditation was associated with a decrease in frontal delta (1–4 Hz) power, especially pronounced in those participants not reporting drowsiness during meditation. Relative increase in frontal theta (4–8 Hz) power was observed during meditation, as well as significantly increased parieto-occipital gamma (35–45 Hz) power, but no other state effects were found for the theta (4–8 Hz), alpha (8–12 Hz), or beta (12–25 Hz) bands. Alpha power was sensitive to condition order, and more experienced meditators exhibited no tendency toward enhanced alpha during meditation relative to the control task. All participants tended to exhibit decreased alpha in association with reported drowsiness. Cross-experimental session occipital gamma power was the greatest in meditators with a daily practice of 10+ years, and the meditation-related gamma power increase was similarly the strongest in such advanced practitioners. The findings suggest that long-term Vipassana meditation contributes to increased occipital gamma power related to long-term meditational expertise and enhanced sensory awareness.
longterm meditators show enhanced occipital gamma (not alpha).
van den Hurk et al, Greater efficiency in attentional processing related to mindfulness meditation. Quarterly Journal of Experimental Psychology, 2009.
In this study, attentional processing in relation to mindfulness meditation was investigated. Since recent studies have suggested that mindfulness meditation may induce improvements in attentional processing, we have tested 20 expert mindfulness meditators in the attention network test. Their performance was compared to that of 20 age- and gender-matched controls. In addition to attentional network analyses, overall attentional processing was analysed by means of efficiency scores (i.e., accuracy controlled for reaction time). Better orienting and executive attention (reflected by smaller differences in either reaction time or error score, respectively) were observed in the mindfulness meditation group. Furthermore, extensive mindfulness meditation appeared to be related to a reduction of the fraction of errors for responses with the same reaction time. These results provide new insights into differences in attentional processing related to mindfulness meditation and suggest the possibility of increasing the efficiency in attentional processing by extensive mental training.
Evan Thompson, Contemplative Neuroscience as an Approach to Volitional Consciousness
This chapter presents a methodological approach to volitional consciousness for cognitive neuroscience based on studying the voluntary self-generation and self-regulation of mental states in meditation. Called contemplative neuroscience, this approach views attention, awareness, and emotion regulation as flexible and trainable skills, and works with experimental participants who have undergone training in contemplative practices designed to hone these skills. Drawing from research on the dynamical neural correlates of contemplative mental states and theories of large-scale neural coordination dynamics, I argue for the importance of global system causation in brain activity and present an “interventionist” approach to intentional causation.
Andrew J. Waters et al,
Associations Between Mindfulness and Implicit Cognition and Self-Reported Affect
Substance Abuse, 2009
Theory suggests that mindful individuals exhibit enhanced attentional processing (e.g., attentional control) and that they maintain a detached perspective to problematic stimuli. For smokers, smoking and affective stimuli are problematic stimuli when they try to quit. In this cross-sectional study, smokers (n = 158) completed 3 modified Stroop tasks (to assess attentional control), 3 Implicit Association Tests (IATs; to assess detached perspective), and a battery of self-report assessments. Degree of mindfulness was negatively associated (P < .05) with self-reported negative affect, perceived stress, and depressive symptom severity, and positively associated (P < .05) with positive affect. Degree of mindfulness was not associated with the ability to disengage attention from smoking or affective stimuli. On the depression IAT, more mindful participants exhibited a more negative IAT effect, suggesting that they may have developed a detached perspective to depression-related stimuli. Theoretical and clinical implications of the data are discussed.
Saturday, January 9, 2010
How are scientists, in the deepest corners of their personality, motivated to carry out the research they do?
Just read a terrific interview with Lee Nadler, the Harvard oncologist who pioneered the discovery of monoclonal antibodies and their use in treatment of blood cancers. In the interview, he was touchingly personal and candid about his own upbringing. And he also described, in a full bodied way, what motivated him as a scientist. Not least was his desire to escape his family, especially his difficult, embarrassing father in Queens.
The personal stuff was quite moving and unusually revealing for a Harvard medical scientist.
What also struck me was his story of his own personal trajectory in science, how events as random as an afternoon conversation with a friend developed into a lifelong monoclonal research agenda.
I also just read the story of Eugene Braunwald's career at UCSD and Brigham and Womens as an investigator of heart attack -- he was the first to develop treatments for people undergoing active heart attacks. He has probably saved thousands/millions of lives. His story is interesting in the way that he is one of the first to bring together in a geniunely translational way molecular biology with treatments of disease.
The father of all of this research was Jacques Loeb, the early 1900s biologist who famously rejected vitalism. His dogma was: All biology can be reduced to biochemical cellular phenomena.
So, having considered all of this, the thing that came to mind was the question of whether "information" or "coordination" based cellular hypotheses (how do cells coordinate activity, share information etc) might be pushing back, however slightly, on the anti-vitalist, reductionist idea somewhat. Certainly the cortical dynamics hypotheses, which sanction action at a distance (through synchrony) and subtle "informational" interactions across many different cortical areas (related to many different subtle behaviors such as observing the pain or action of another, imagining music or sound or touch, undergoing an illusion that a rubber arm really belongs to you). And, then there is my idea that beta and piper/gamma rhythms suggest that brain rhythms extend into (and may possibly helpt to coordinate) a broad range of peripheral physical/sensorimotor processes: pain, balance, movement, blood flow.
The main point 1: how does my intellectual agenda work? Do my ideas, hypotheses and proposed experiments challenge some of these "big ideas"?
If these brain dynamic processes, in which motor cortex neurons are entrained and organized into cortical assemblies that exert influence on embodied physiological processes, then this would suggest a slight modifcation of Jacques Loeb's dogma. I'm sure I will have more to say about this at a later time.
The main point 2: Noting the questions that matter for me, right now.
For right, now I think it's enough to note the questions that I am interested in: why are people really, in the deepest corners of their personality, motivated to carry out the research they do? How are lifelong research agendas launched by brief encounters with a subject or conversations with a person or fleeting personal experiences with illness or healing? How do abstract intellectual dogmas (Loeb's sustained effort to destroy theories of vitalism and promote reductionistic biology, for example) relate to a one's personal situation?
For me these questions feel especially charged.
The personal stuff was quite moving and unusually revealing for a Harvard medical scientist.
What also struck me was his story of his own personal trajectory in science, how events as random as an afternoon conversation with a friend developed into a lifelong monoclonal research agenda.
I also just read the story of Eugene Braunwald's career at UCSD and Brigham and Womens as an investigator of heart attack -- he was the first to develop treatments for people undergoing active heart attacks. He has probably saved thousands/millions of lives. His story is interesting in the way that he is one of the first to bring together in a geniunely translational way molecular biology with treatments of disease.
The father of all of this research was Jacques Loeb, the early 1900s biologist who famously rejected vitalism. His dogma was: All biology can be reduced to biochemical cellular phenomena.
So, having considered all of this, the thing that came to mind was the question of whether "information" or "coordination" based cellular hypotheses (how do cells coordinate activity, share information etc) might be pushing back, however slightly, on the anti-vitalist, reductionist idea somewhat. Certainly the cortical dynamics hypotheses, which sanction action at a distance (through synchrony) and subtle "informational" interactions across many different cortical areas (related to many different subtle behaviors such as observing the pain or action of another, imagining music or sound or touch, undergoing an illusion that a rubber arm really belongs to you). And, then there is my idea that beta and piper/gamma rhythms suggest that brain rhythms extend into (and may possibly helpt to coordinate) a broad range of peripheral physical/sensorimotor processes: pain, balance, movement, blood flow.
The main point 1: how does my intellectual agenda work? Do my ideas, hypotheses and proposed experiments challenge some of these "big ideas"?
If these brain dynamic processes, in which motor cortex neurons are entrained and organized into cortical assemblies that exert influence on embodied physiological processes, then this would suggest a slight modifcation of Jacques Loeb's dogma. I'm sure I will have more to say about this at a later time.
The main point 2: Noting the questions that matter for me, right now.
For right, now I think it's enough to note the questions that I am interested in: why are people really, in the deepest corners of their personality, motivated to carry out the research they do? How are lifelong research agendas launched by brief encounters with a subject or conversations with a person or fleeting personal experiences with illness or healing? How do abstract intellectual dogmas (Loeb's sustained effort to destroy theories of vitalism and promote reductionistic biology, for example) relate to a one's personal situation?
For me these questions feel especially charged.
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