Consciousness and how it got to be that way
Wednesday, November 27, 2013
Sunday, November 10, 2013
Sunday, November 3, 2013
The Physical Diversity of Uralic Speakers
The Uralic language family has always intrigued me. Partly it's because some people think that there is a Uralic substrate to proto-Germanic (see Kalevi Wiik); partly it's because Uralic speakers live in the center of a continent that is at once the center of the Old World, and in many ways not thoroughly explored with its interior still largely wild and uninhabited. But it's really intriguing to see how different Uralic speakers look from one another. They range from blonde, Scandinavian-looking, about-as-white-as-you-can-get Finns and Saami, to very Asiatic-appearing Nenets people in north central Siberia. Is this because there really aren't many genes for face shape, eye shape and hair type - that is, if you looked at, say, Germans and Spaniards genetically, are they genetically as distant on average as Finns and Nenets (just a few genes) but the differing German and Spanish genes don't happen to all be represented in easy-to-spot features? Or is there really a greater genetic distance? In which case, are these people whose ancestors adopted the language, or were they such a small group of hunter-gatherers running into big Turkic and Indo-European populations that their genes were swamped by whoever they met?
The interesting thing is that here the Urals form a fairly clear boundary for these genes. The Udmurts to the west (one of the groups above) are famous for being the most red-haired people on the planet, while on the other hand it's not hard to imagine that the Nenets family above is related to Native Americans and Inuit. (The Udmurts are the first one and the Nenets second, but I probably didn't have to tell you which are which!) But of course there is still cross-over between the two, and it's interesting precisely because most of us in the U.S. don't see these traits represented in the same people very often.
The interesting thing is that here the Urals form a fairly clear boundary for these genes. The Udmurts to the west (one of the groups above) are famous for being the most red-haired people on the planet, while on the other hand it's not hard to imagine that the Nenets family above is related to Native Americans and Inuit. (The Udmurts are the first one and the Nenets second, but I probably didn't have to tell you which are which!) But of course there is still cross-over between the two, and it's interesting precisely because most of us in the U.S. don't see these traits represented in the same people very often.
Friday, November 1, 2013
Does Mindfulness Act Through Modulation of Serotonergic Circuitry?
Investigating the connections between mindfulness meditation and the brain's serotonergic systems seems like a promising avenue of research. Mindfulness may be a way to directly influence this system based on observations from several domains.
1) A bedrock principle of psychopharmacology is that increasing the amount of serotonin in synapses improves depression and anxiety.
2) Acute doses of HT2A agonists (e.g. psilocybin) can also improve depression. These agents produce brief and intense sensory experiences. At low doses, subjects do not report hallucinations, but do report that sensations seem more intense and more affectively pleasant (e.g., colors are brighter).
3) Mindfulness, which is focused concentration on sensory input, has been shown to be effective in reducing depressive symptoms in RCTs (van Aalderen et al 2011).
4) Therefore, concentrating on sensory input as with mindfulness may produce similar effects to the SSRIs and HT2A agonists, mediated by the same pathway.
In a sense, giving SSRIs (or the more powerful one-time punch of psilocybin) may produce an exogenously-created mindfulness. No research has yet been done on the involvement of serotonergic circuitry with mindfulness meditation's effects.
Many of the measures correlating mindfulness meditation to outcome concern decreased rumination. To that end, the introspective among us should take note of this quote from a 2013 paper by Paul et al in Social Cognitive and Affective Neuroscience: "Our results suggest non-reactivity to inner experience is the key facet of mindfulness that protects individuals from psychological risk for depression."
1) A bedrock principle of psychopharmacology is that increasing the amount of serotonin in synapses improves depression and anxiety.
2) Acute doses of HT2A agonists (e.g. psilocybin) can also improve depression. These agents produce brief and intense sensory experiences. At low doses, subjects do not report hallucinations, but do report that sensations seem more intense and more affectively pleasant (e.g., colors are brighter).
3) Mindfulness, which is focused concentration on sensory input, has been shown to be effective in reducing depressive symptoms in RCTs (van Aalderen et al 2011).
4) Therefore, concentrating on sensory input as with mindfulness may produce similar effects to the SSRIs and HT2A agonists, mediated by the same pathway.
In a sense, giving SSRIs (or the more powerful one-time punch of psilocybin) may produce an exogenously-created mindfulness. No research has yet been done on the involvement of serotonergic circuitry with mindfulness meditation's effects.
Many of the measures correlating mindfulness meditation to outcome concern decreased rumination. To that end, the introspective among us should take note of this quote from a 2013 paper by Paul et al in Social Cognitive and Affective Neuroscience: "Our results suggest non-reactivity to inner experience is the key facet of mindfulness that protects individuals from psychological risk for depression."
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