In one experiment, participants either drank five cups of water (about 750 milliliters), or took small sips of water from five separate cups. Then, after about 40 minutes — the amount of time it takes for water to reach the bladder — the researchers assessed participants’ self-control. Participants were asked to make eight choices; each was between receiving a small, but immediate, reward and a larger, but delayed, reward. For example, they could choose to receive either $16 tomorrow or $30 in 35 days.
The researchers found that the people with full bladders were better at holding out for the larger reward later. Other experiments reinforced this link; for example, in one, just thinking about words related to urination triggered the same effect.
“You seem to make better decisions when you have a full bladder,” Tuk says (via.)
This is mildly to moderately freakish.
That division of labor suggests that the brain’s structure follows a predetermined, genetic blueprint. However, evidence is mounting that brain regions can take over functions they were not genetically destined to perform. In a landmark 1996 study of people blinded early in life, neuroscientists showed that the visual cortex could participate in a nonvisual function — reading Braille.
Now, a study from MIT neuroscientists shows that in individuals born blind, parts of the visual cortex are recruited for language processing. The finding suggests that the visual cortex can dramatically change its function — from visual processing to language — and it also appears to overturn the idea that language processing can only occur in highly specialized brain regions that are genetically programmed for language tasks.
“Your brain is not a prepackaged kind of thing. It doesn’t develop along a fixed trajectory, rather, it’s a self-building toolkit. The building process is profoundly influenced by the experiences you have during your development,” says Marina Bedny, an MIT postdoctoral associate in the Department of Brain and Cognitive Sciences and lead author of the study, which appears in the Proceedings of the National Academy of Sciences the week of Feb. 28. (via.)
Neural plasticity is a wonderful thing!
Many studies have suggested that males tend to be more physically and verbally aggressive than females. According to a new study, to be published in Psychological Science, a journal of the Association for Psychological Science, it may not be the case that women are less competitive than men—they may just be using a different strategy to come out ahead. Specifically, women may rely more on indirect forms of aggression, such as social exclusion. [...]
“As their primary competitive strategy to combat any social threat, females may attempt to form an exclusionary alliance, whereas males may endeavor to unilaterally and directly dominate an opponent,” the authors write. Women may be more sensitive than men to social exclusion, and when they feel threatened by the prospect of being left out, a woman’s first response may be to socially exclude a third party.
Preemptive social exclusion appears to be a valuable strategy for women because it allows them to protect their relationships by keeping an outsider at bay. Benenson points out that this may require a re-evaluation of presumed sex differences in competitiveness. She comments, “The same-sex social worlds of boys and girls and men and women then differ in that females have to worry about alienating others, whereas males worry about getting beaten up.” (via.)
Basically, their conclusions came from a game that men and women both played. Follow the via link for more information.
I’ve plugged the fact before that there’s a common anecdote about autistic children’s behavior being temporarily altered by fevers.
I ran across this interesting article on the brain region known as the “locus coeruleus” which apparently creates noradrenaline.
“The LC-NA system is the only brain system involved both in producing fever and controlling behavior,” says co-author Dominick P. Purpura, M.D., dean emeritus and distinguished professor of neuroscience at Einstein.
The locus coeruleus has widespread connections to brain regions that process sensory information. It secretes most of the brain’s noradrenaline, a neurotransmitter that plays a key role in arousal mechanisms, such as the “fight or flight” response. It is also involved in a variety of complex behaviors, such as attentional focusing (the ability to concentrate attention on environmental cues relevant to the task in hand, or to switch attention from one task to another). Poor attentional focusing is a defining characteristic of autism. (via.)
According to this arstechnica article fruit flies lacking (or with extremely low levels of) dopamine suffer from extreme lethargy, and a type of masochism!
Flies that apparently lack dopamine signaling manage to live just as long as their peers. They do, however, end up turning into lethargic masochists. [...]
However, they’re nowhere close to normal. Compared to their normal peers, they were very lethargic, moving relatively little through the course of their normal lives, and not expending the effort to move out of the path of a mild electric current. They spent a lot of their time in the fly equivalent of sleep, even during daylight hours, when they are normally active. Despite the lethargy, however, caffeine was still able to give them a kick start, suggesting that there’s an intact activity control that is simply not getting the sorts of cues it needs without dopamine around.
The same sorts of issues showed up when feeding and visual activity were tested. The flies that lacked dopamine ate only about a third as much as their normal peers and weren’t interested in sugar water even after having been starved. They were still able to respond to sugar and eat, however, which suggests that the animals’ brains still have a feeding capacity that ends up going unused without dopamine. The flies also had normal vision and could use it for spatial orientation, but would no longer move towards light (a phenomenon called phototaxis).
The weirdest effect, however, came when the flies were tested for learned aversion, in which an electric shock is associated with a particular odor. Instead of learning to avoid the shock, however, the dopamine-deficient Drosophila ended up being attracted to the odor, hence the authors’ use of the term “masochistic” to describe the flies’ behavior. (via.)
A friend of mine shared this unusual link with me:
How to Make a Complete Map of Every Thought you Think
That’s the title of a book I wrote. Guess what it’s about!
It’s about how to make a complete map of every thought you think! But it has some other things in there; It talks about visual language, maps, computerized notebooks, theory of notebooks, yadda yadda yadda.
I’m afraid it’s not really written well, but if you are interested in the topic of intelligence augmentation and notebooks, I think you’ll overlook it’s obvious flaws, for an enjoyable experience.
I only took the most cursory glance at the actual content of the book which is in multiple formats. The lack of editing of the book hints at a little crazy, but of course, that just makes it that much more interesting. Probably worth a read through at some point! Check it out.