this experiment claims to show that
(1) when rats are sleep-deprived, small populations of rat brain neurons can fall asleep while the rest of the rat is awake, and
(2) this may correspond to performance degradation
summary:
http://arstechnica.com/science/news/2011/04/if-you-only-feel-half-awake-you-probably-are.ars
article:
http://www.nature.com/nature/journal/v472/n7344/full/nature10009.html
i haven’t read the actual article yet…
Read on for a guest-posted ad for WNYC’s radio lab (http://www.radiolab.org)
Transcranial magnetic stimulation (TMS) is a popular technology for stimulating human cortical neurons, due to its safety, noninvasiveness, and efficacy. A TMS device is just a little coil of wire, through which 10,000 Amps of current is cranked during a period of only a few hundred microseconds; the resultant rapidly-changing magnetic field induces eddy currents in the brain. Depending on the protocol used, TMS can drive/inhibit a region of cortex corresponding to roughly a cubic centimeter or two, and is being explored for the treatment of depression, the reduction of auditory hallucinations during schizophrenia, and the alleviation of tinnitus and migraines. Thousands of papers on medicine and psychology have been written using this tool.
Yet the device itself is expensive and rare — they can run from $20,000 to $50,000 or even more, despite the fact that they are, in essence, a coil, a switch, a bank of capacitors, and a power supply. Much of the art lies in making the devices safe and fail-proof. Is it possible to hack/engineer a system that is safe, fault-tolerant, efficacious, and inexpensive? And furthermore, can we facilitate a community that will devise such devices, and share information about protocols and approaches to brain hacking?
This past August at Foo Camp, a hackers’ conference in Northern California, a group of people got together and set out to do just that. We are designing a safe, noninvasive, modular, and “open source” brain stimulator that will open up the field of circuit modulation to a wider audience. Members of the group include therapists and mental health professionals, engineers, programmers, and others interested in either the development of such devices, or the sharing of information on this front. Key to the design is safety — we want to make sure that the devices we create are as safe as devices on the market. Also, all the information is released under the Creative Commons “Attribution and Sharealike” license. This is a new model for “open source” medical device development — which may move it beyond the domain of simply creating “cool toys,” and to creating real devices.
You can find out more information, or contribute to the project, or learn from the project, at
http://transcenmentalism.org/OpenStim/
–Ed
Intelligent Life 2006 | From A to Zzzzz
Introducing CX717, a drug being developed by Cortex Pharmaceuticals of Irvine, California. It’s the first of what promises to be many aimed at detaching people from the daily routine of eight hours each for work, rest and play.
Tests conducted on rhesus monkeys last year suggest that CX717 can wire users to remain awake for 36 hours without the jitters, euphoria and eventual crash that come after mega-doses of caffeine or amphetamines. Further down the line are even more radical compounds—stimulants that can wipe out sleep for several days at a stretch, and pills that deliver a whole night’s shut-eye in two hours.
More information about the ampakine CX717 can be found here. We previously mentioned the delay match-to-sample performance improvement of monkeys on CX717.
I don’t know quite what to make of this. In fact, I just don’t understand what is going on. But I can definitely think of examples from my own life where this is true. Sometimes not thinking about a problem really does lead to its solution and it’s fascinating to think about why this may be.
Also, the authors draw a connection between what they call unconscious thought (as performed in their experiments) and insights that can come “after sleeping on it”; I’m not sure these phenomena are the same. I think sleep taps into deeper organization processes that are not available on the timescale of unconscious thought, as given in the experiment.
Abstract:
Contrary to conventional wisdom, it is not always advantageous to engage in thorough conscious deliberation before choosing. On the basis of recent insights into the characteristics of conscious and unconscious thought, we tested the hypothesis that simple choices (such as between different towels or different sets of oven mitts) indeed produce better results after conscious thought, but that choices in complex matters (such as between different houses or different cars) should be left to unconscious thought. Named the “deliberation-without-attention” hypothesis, it was confirmed in four studies on consumer choice, both in the laboratory as well as among actual shoppers, that purchases of complex products were viewed more favorably when decisions had been made in the absence of attentive deliberation.
The nice NYT article on the function of sleep follows on a recent NIH-funded Nature insight series.
Some interesting facts from the NYT article:
Scientific Clearing House: Mind enhancing drugs
Apparently, CX717, an ampakine developed by Cortex Pharmaceuticals, shows some signs of preventing the cognitive impairment brought on by sleep deprivation. The original study in PLoS Biology (news & views) was done with monkeys.
Neat article in this month’s Nature Neuroscience on how gap junctions (ie. direct, non-synaptic coupling) between neurons in the superchiasmatic nucleus might be responsible for their millisecond-scale synchrony and time-keeping abilities. Also, a variation in the amount of coupling (eg. number of gap junctions) was observed that followed a night-day cycle. Read on below for the news and views.
Continue reading
Their sleep cycle can be different than just their circadian rhythm: if you sleep deprive ’em, they need more sleep. A bunch of molecular similarities, too (i.e. some sleep-related drugs do the same things to flies).
Continue reading
Reto Huber, M. Felice Ghilardi, Marcello Massimini and Giulio Tononi found that the strength of slow wave activity (SWA) during sleep increases LOCALLY in areas that learned something during the day.
neurodudes 