"...various indirect mechanisms possibly mediating this phenomenon were tested: accommodation, brightness, increases in arousal by increased mental effort. None of these behavioral tests could support an indirect strategy as the mode of action"
591 karma · joined February 14, 2012
"...various indirect mechanisms possibly mediating this phenomenon were tested: accommodation, brightness, increases in arousal by increased mental effort. None of these behavioral tests could support an indirect strategy as the mode of action"
When it comes to data, the 2016 National Household Education Survey by the National Center for Education Statistics shows that 51% of parents selected "A desire to provide religious instruction" as an "important" reason for homeschooling their children, and 67% selected "A desire to provide moral instruction" as an "important" reason for homeschooling [0, in bar plot form; 1, original data].
[0] https://responsiblehomeschooling.org/research/summaries/reas... [1] https://nces.ed.gov/pubs2017/2017102.pdf
[0] https://www.globalresearch.ca/the-real-reason-america-used-n...
I assume their clickbait subsidizes their investigative journalism, a business model that gives me hope given the importance of investigative journalism. Unfortunately that hope is tempered by the recent round of layoffs.
[0] https://www.buzzfeednews.com/investigations [1] https://www.pulitzer.org/finalists/staff-buzzfeed-news
But I'm a little confused why you made this comment on an earlier HN post about Shannon Labs: https://news.ycombinator.com/item?id=17675617
It's not clear why they faked his death, but apparently it led to something happening.
[0] https://www.theguardian.com/world/2018/may/30/russian-journa...
Coordination of movement in space (for example something like grasping an object) is more dependent on parietal cortex & the dorsal visual stream (the so-called "where" pathway), and the cerebellum.
"Visuospatial skill", as typified by tasks like mental object rotation, is more ascribable to temporal cortex & the ventral visual stream (the so-called "what" pathway, responsible for object recognition). However, it often requires both ventral and dorsal visual cortex.
Navigation is hippocampus-dependent. However, the hippocampus is not a "GPS". I cannot emphasize this strongly enough. It is a hub for integrating and associating disparate information from across the brain in order to form representations of and the relationships between behaviorally-relevant states. This explains why the hippocampus is also involved in "navigating" abstract state spaces, for example turn-based game states [0] or auditory frequency [1], when they're behaviorally relevant. It gets analogized as a GPS because 1) most of the research involves spatial tasks, so space is the behaviorally-relevant dimension, 2) a certain Nobel Prize winner does not feel the need to update his theory, and 3) "Hippocampus = GPS" is too sexy and intuitive of an analogy, especially for the lay press.
The idea of the hippocampus as an "associative engine" also helps unify its seemingly disparate roles in "navigation" and memory when you consider that a memory is just information from disparate brain areas that's been associated via temporal correlation because of its behavioral relevance. It also explains why researchers observe "place cells" and "time cells" and "head direction cels" and "eye position cells": because these variables are behaviorally relevant (i.e. important for maximizing reward) in the task the animal is performing.
[0] https://onlinelibrary.wiley.com/doi/pdf/10.1002/hipo.22523
And the quantity, youth, and low latency of organs for transplant exclude every possibility except harvesting.
The Falun Gong desires to exist.
This Vanity Fair piece provides a fair amount of character background: https://www.vanityfair.com/news/2016/09/elizabeth-holmes-the...
source: https://www.nature.com/articles/nature11400
abstract: Antibiotics administered in low doses have been widely used as growth promoters in the agricultural industry since the 1950s, yet the mechanisms for this effect are unclear. Because antimicrobial agents of different classes and varying activity are effective across several vertebrate species, we proposed that such subtherapeutic administration alters the population structure of the gut microbiome as well as its metabolic capabilities. We generated a model of adiposity by giving subtherapeutic antibiotic therapy to young mice and evaluated changes in the composition and capabilities of the gut microbiome. Administration of subtherapeutic antibiotic therapy increased adiposity in young mice and increased hormone levels related to metabolism. We observed substantial taxonomic changes in the microbiome, changes in copies of key genes involved in the metabolism of carbohydrates to short-chain fatty acids, increases in colonic short-chain fatty acid levels, and alterations in the regulation of hepatic metabolism of lipids and cholesterol. In this model, we demonstrate the alteration of early-life murine metabolic homeostasis through antibiotic manipulation.
1) MIT is very good at publicity and press.
2) Causal neuroscience experiments are still technically challenging to implement in complex behaving organisms (e.g. monkeys and humans). We have methods such as microstimulation (invasive) and transcranial magnetic stimulation (non-invasive), but these methods are pretty ham-fisted. They indiscriminately activate (or deactivate) all the neurons in and passing through a given volume in the brain (optogenetics is promising in this regard, but it's still a nascent technology in monkeys). So while this study may appear weak because it's correlational, it may actually represent a meaningful step forward in the field.
It's unclear whether local field potentials (LFPs), of which "beta rhythms" are one specific frequency band (approximately 12-30hz), are actually a mechanism that the brain uses to transmit information. Information is known to be transmitted via the discharges of single neurons; LFPs represent the aggregate activity of tens of thousands of neurons within ~3mm of a recording electrode. It's possible that these aggregate voltage fluctuations feed back onto the activity of single neurons [0], but LFPs are generally considered an emergent property of populations of neurons as opposed to an information transmission mechanism in their own right.
[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210929/#!po=22...