Normal consciousness relies, at least in part, on the brain’s Default Mode Network (DMN), according to neuroscientist Robin Carhart-Harris, head of psychedelic research in the brain sciences division of the Imperial College of London medical school. The DMN is a network of interacting brain regions that acts as a cognitive transit hub, integrating and assimilating information. As the name implies, it’s the usual system of organization for your mind. Carhart-Harris says the DMN “gives coherence to cognition” by connecting different regions of the brain, and is considered the “orchestrator of the self.”

Carhart-Harris and his colleagues found what seems to be an important function of the DMN inadvertently. While studying brain networks, they got curious about what changes might occur when people are under the effects of hallucinogens. In studies analyzing the effects of psilocybin on brain wave oscillation and blood flow, they found that when the DMN was inactive, an alternate network of consciousness seemed to arise.

When some study subjects tested psilocybin, they reported a strong sense of interconnectedness, as well as spiritual, magical, and supernatural feelings.

In the alternate mode, brains produced a different world that offered other sensations and realizations than in everyday life. In this mode, the self wasn’t the protagonist of the narrative. Meanwhile, scans of blood flow and brain wave oscillations showed new, unusual—but orderly and synchronous—connections forming between cortical regions, as if the brain was reorganizing its network. This led Carhart-Harris to posit that the DMN generates the feeling we each have that we’re individuals, a feeling that manifests very strongly as reality. And that means we can temporarily switch off, or mute, this part of the brain.

{ Quartz | Continue reading }

According to the famous work of Roger Sperry and Michael Gazzaniga, “split brain” patients seem to experience a split in consciousness: the left and the right side of their brain can independently become aware of, and respond, to stimuli. Split brain patients are those who underwent surgery to sever the corpus callosum, the nerve tract connecting the two hemispheres of the brain.

{ Neuroskeptic | Continue reading }

art { Leah Schrager }

There is no robust evidence of nonhuman suicides, notwithstanding countless opportunities for such self-killings, if they occurred, to be documented by the world’s farmers, animal breeders, naturalists, and scientists. We are left with anecdote and fable, including the scorpion’s self-sting, proffered by Peña-Guzmán as an example of animal suicide despite clear evidence that scorpions cannot sting themselves to death.

Scorpions are immune to their own venom, presumably because selection has eliminated the germ lines of scorpions that were not so protected. The ubiquity of such specific, self-preserving adaptations connects to a third, theoretical, problem with animal suicide: the absence of a coherent explanation as to how selection could favour and maintain such a capability. […]

Suicide is not observed in nonhumans for a straightforward evolutionary reason: any genes that permitted suicide would have been eliminated along with the suicides’ bodies. Any animal that, in the absence of restraints, was capable of escaping its pain and suffering by self- killing would be expected to seize the opportunity, because some pain is unavoidable in the Malthusian theatre in which selection plays out, and because pain is designed to motivate action to escape. A suicidal animal, if it appeared, would face a predictable and severe adaptive problem – the kind of problem that selection would expectably and powerfully have addressed in the evolutionary past.

The most parsimonious explanation for the apparent absence of suicide among younger children, the severely cognitively impaired, and nonhuman animals, is that these populations lack the cognitive wherewithal to conceive and enact it.

{ Animal Sentience | PDF }

acrylic on canvas { Olivier Mosset, Untitled, 1970 }

We explored the effect of revealing or conservative attire on perceptions of women’s leadership competence. We also used eye-tracker technology to determine whether looking at sexualized body parts (i.e., breasts, hemline) was related to lower perceptions of leadership competence and electability.

A female candidate for a student senate presidency at a U.S. university wearing revealing clothing was perceived by 191 college students as less honest and trustworthy, electable, and competent than one wearing conservative clothing. Sexualized body parts were looked at longer when the candidate was wearing revealing clothing compared to conservative clothing. Furthermore, mediation analyses indicated that the revealing clothing led participants to gaze at sexualized body parts, which, in turn, led to perceiving the candidate as less honest/trustworthy, which lowered their evaluations of her competence and electability.

These findings suggest that viewing a woman in a sexy outfit can lead others to stare more at her body and make negative evaluations of her personal attributes.

{ Sex Roles | Continue reading }

art { Corinne Dodenhoff }

Why the Victorian era saw a surge in female births and war begets boys

There is empirical evidence that heavy sexual activity increases the chances that conception will occur before the most fertile time of the female cycle, as the woman may be pregnant by then. And the data also suggest that, possibly for hormonal reasons, such conceptions are slightly more likely to be boys. “It doesn’t take much imagination to suppose that the ends of wars, with servicemen home on leave or returning home, are associated with fairly intense sex – more babies were born in the UK in 1919 than any other year in history. Put all these together and you get the conclusion – frantic fornication breeds boys.”

[…]

Which brings us back to the mysterious surge of female births in the late Victorian period. Could it be that, in the same vein in which heavy sexual activity increases the sex ratio, a  trend towards sexual inactivity lowers it? “Victorian morality” distinguished itself through a set of values that espoused sexual restraint, with an increased condemnation of masturbation and sexual activity in general, repressing any form of sexuality other than penetrative intercourse. And indeed, statistics reflect a steady decline of sexual activity throughout the Victorian period, reaching its lowest point in the year 1898. But as there was less sex going on, conception tended to occur around the most fertile time of the months, bestowing a (relative) excess of baby girls on the Victorians.

{ Rolf Degen | Continue reading }

Hypothesis 1

Up to circa two decades age, it was generally supposed – but without hard supporting evidence – that pregnant women exposed to adverse environmental circumstances were at increased risk of foetal loss, and that male foetuses were at greater risk than female foetuses; and that therefore the liveborn infants produced by stressed women contained a higher proportion of daughters. That hard evidence has now been accumulated in a series of papers by Catalano and colleagues, and others.

Using time-series analysis, it has been shown that the Sex ratios at birth (SRB) briefly declined, slightly but significantly, some three to five months after many catastrophic and other adverse events e.g. the terrorist attacks on September 11th, 2001; the Troubles in Northern Ireland (1969–1998), the Breivik shooting in 2011 in Norway, the Sandy Hook shooting in 2012 in Connecticut; the assassination of President Kennedy [though the effect in this case was more marked in non-White than White births]. […]

Thus there is overwhelming evidence that sex ratios at birth are partially controlled by maternal stress-induced selective culling of frail males in utero, resulting in a conception cohort with a low sex ratio at birth. It has also been postulated that the ratio may be skewed because of fertilization of non-optimally matured oocytes under these circumstances. Moreover, it has also been hypothesized that higher coital rates will lead to ejaculation of newly formed spermatozoa cells, possibly leading to a preponderance of Y-sperm since it is also hypothesized that X-sperm age faster and are eliminated earlier.

However, it will be appreciated that selective culling of frail males during pregnancy cannot explain some of the established variations of SRB. First, it cannot explain why some reported sex ratios are higher than prevailing norms. Second, it cannot explain why these norms almost always exceed 0.5 (equal numbers of males and females).

Hypothesis 2

It has been hypothesized that human sex ratios at birth are partially controlled by the parental hormone levels of both parents around the time of conception. Ex hypothesi, high levels of testosterone (in either parent) and/or of oestrogen (in the mother), are associated with subsequent male births. And high levels of gonadotrophins (in either parent) are associated with subsequent female births. Most of this evidence is observational and correlational, and is in accordance with the hypothesis of Trivers & Willard.

{ Early Human Development | Continue reading }

lithograph { Ellsworth Kelly, Small Blue Curve, 2013 }

We’d all like to be a little happier.

The problem is that much of what determines happiness is outside of our control. Some of us are genetically predisposed to see the world through rose-colored glasses, while others have a generally negative outlook. Bad things happen, to us and in the world. People can be unkind, and jobs can be tedious.

But we do have some control over how we spend our leisure time. That’s one reason why it’s worth asking which leisure time activities are linked to happiness, and which aren’t.

In a new analysis of 1 million U.S. teens, my co-authors and I looked at how teens were spending their free time and which activities correlated with happiness, and which didn’t.

[…]

Every year, teens are asked about their general happiness, in addition to how they spend their time. We found that teens who spent more time seeing their friends in person, exercising, playing sports, attending religious services, reading or even doing homework were happier. However, teens who spent more time on the internet, playing computer games, on social media, texting, using video chat or watching TV were less happy.

In other words, every activity that didn’t involve a screen was linked to more happiness, and every activity that involved a screen was linked to less happiness. The differences were considerable: Teens who spent more than five hours a day online were twice as likely to be unhappy as those who spent less than an hour a day.

Of course, it might be that unhappy people seek out screen activities. However, a growing number of studies show that most of the causation goes from screen use to unhappiness, not the other way around. […]

A similar trend might be occurring for adults: My co-authors and I previously found that adults over age 30 were less happy than they were 15 years ago, and that adults were having sex less frequently.

{ Quartz | Continue reading }

Drawing on the past well-being literature, the authors propose that a person’s chronic happiness level is governed by 3 major factors: a genetically determined set point for happiness, happiness-relevant circumstantial factors, and happiness-relevant activities and practices.

{ Review of General Psychology | PDF }

If you write clearly, then your readers may understand your mathematics and conclude that it isn’t profound. Worse, a referee may find your errors. Here are some tips for avoiding these awful possibilities.

1. Never explain why you need all those weird conditions, or what they mean. For example, simply begin your paper with two pages of notations and conditions without explaining that they mean that the varieties you are considering have zero-dimensional boundary. In fact, never explain what you are doing, or why you are doing it. The best-written paper is one in which the reader will not discover what you have proved until he has read the whole paper, if then

2. Refer to another obscure paper for all the basic (nonstandard) definitions you use, or never explain them at all. This almost guarantees that no one will understand what you are talking about

[…]

11. If all else fails, write in German.

{ J.S. Milne | Continue reading }

photos { Left: William Henry Jackson, Pike’s Peak from the Garden of the Gods, Colorado Midland Series, ca.1880 | Right: Ye Rin Mok }

People’s capacity to generate creative ideas is central to technological and cultural progress. Despite advances in the neuroscience of creativity, the field lacks clarity on whether a specific neural architecture distinguishes the highly creative brain. […]

We identified a brain network associated with creative ability comprised of regions within default, salience, and executive systems—neural circuits that often work in opposition. Across four independent datasets, we show that a person’s capacity to generate original ideas can be reliably predicted from the strength of functional connectivity within this network, indicating that creative thinking ability is characterized by a distinct brain connectivity profile.

{ PNAS | Continue reading | Read more }

related { Neurobiological differences between classical and jazz musicians at high and low levels of action planning }

This study documents that men and women experience and perform consumer shopping differently. […]

There is an abundant literature on sex differences in spatial abilities and object location that follow from the specific navigational strategies associated with hunting and gathering in the ancestral environment. In addition to sex differences in navigational strategies, the unique features of hunting and gathering may have influenced other aspects of foraging psychology that underlie sex differences in modern male and female shopping experiences and behaviors. […]

It is well accepted that humans do not simply develop new behaviors for every new situation we encounter but instead modify or extend existing behaviors to suit the new situation. Thus, the behaviors we exhibit in a modern and recently developed (i.e., with respect to an evolutionary timeframe) shopping mall, should be based on previously developed behaviors and skills. We believe, and study findings support this belief, that modern shopping behaviors are an adaptation of our species’ ancestral hunting and gathering skills. […]

For the most part, contemporary stereotypes of women in modern industrial countries perceive women as enjoying shopping more than men. Our research provides evidence that this popular stereotype exists because most shopping activities have a greater similarity to women’s traditional activities of foraging and gathering than they do to men’s traditional activity of hunting. The results of our study show that shopping has significantly more in common with gathering than it does with hunting.

{ Journal of Social, Evolutionary, and Cultural Psychology | Continue reading }

related { Hunter-gatherer lifestyle could help explain superior ability to ID smells }

To test the relationship between ambient temperature and personality, we conducted two large-scale studies in two geographically large yet culturally distinct countries: China and the United States. […] Our findings provide a perspective on how and why personalities vary across geographical regions beyond past theories (subsistence style theory, selective migration theory and pathogen prevalence theory). As climate change continues across the world, we may also observe concomitant changes in human personality.

{ Nature | Continue reading }

photo { Dana Lixenberg, J 50, 1993 }

Strange-face illusions are produced when two individuals gaze at each other in the eyes in low illumination for more than a few minutes.

Usually, the members of the dyad perceive numinous apparitions, like the other’s face deformations and perception of a stranger or a monster in place of the other, and feel a short lasting dissociation. […]

Strange-face illusions can be considered as ‘projections’ of the subject’s unconscious into the other’s face. In conclusion, intersubjective gazing at low illumination can be a tool for conscious integration of unconscious ’shadows of the Self’ in order to reach completeness of the Self.

{ Explore | Continue reading }

photo { Richard Kern }

When making trust decisions in economic games, people have some accuracy in detecting trustworthiness from the facial features of unknown partners. […] We observed that trustworthiness detection remained better than chance for exposure times as short as 100 ms, although it disappeared with an exposure time of 33 ms.

{ Experimental Psychology | Continue reading }

photo { Miles Alridge }

In what appears to be the first successful hack of a software program using DNA, researchers say malware they incorporated into a genetic molecule allowed them to take control of a computer used to analyze it. […]

To carry out the hack, researchers encoded malicious software in a short stretch of DNA they purchased online. They then used it to gain “full control” over a computer that tried to process the genetic data after it was read by a DNA sequencing machine.  

The researchers warn that hackers could one day use faked blood or spit samples to gain access to university computers, steal information from police forensics labs, or infect genome files shared by scientists.  

{ Technology Review | Continue reading }

Eye movements of 105 heterosexual undergraduate students (36 males) were monitored while viewing photographs of men and women identified as a potential mate or a potential friend. Results showed that people looked at the head and chest more when assessing potential mates and looked at the legs and feet more when assessing potential friends.

{ Archives of Sexual Behavior | Continue reading }

photo { Michelle Pfeiffer photographed by Jim Britt, 1979 }

Neurobiological research on memory has tended to focus on the cellular mechanisms involved in storing information, known as persistence, but much less attention has been paid to those involved in forgetting, also known as transience. It’s often been assumed that an inability to remember comes down to a failure of the mechanisms involved in storing or recalling information. 

“We find plenty of evidence from recent research that there are mechanisms that promote memory loss, and that these are distinct from those involved in storing information,” says co-author Paul Frankland.

One recent study in particular done by Frankland’s lab showed that the growth of new neurons in the hippocampus seems to promote forgetting. This was an interesting finding since this area of the brain generates more cells in young people. The research explored how forgetting in childhood may play a role in why adults typically do not have memories for events that occurred before the age of four years old. 

{ University of Toronto | Continue reading }

art { Masao Mochizuki, The Air Power of the World, 1976 }

Chang et al. investigated the well-known asymmetry of the scrotum in man and showed that in right-handed subjects the right testis tended to be higher, whereas the converse applied in left-handed subjects.

{ Nature | PDF }

{ On the Inability to Ignore Useless Advice }

oil marker on acrylic on canvas on wood { François Morellet, Rococoncret n°4, 2012 }

The urge to be permanently blind is an extremely rare mental health disturbance. The underlying cause of this desire has not been determined yet. […] Only 5 people with an urge to be blind were found to participate in the study (4 female, 1 male). […]

The hypothesis that people with a desire for blindness suffer from a significantly higher visual overload in activities of daily living than visually healthy subjects was confirmed.

{ Case Reports in Ophthalmology | Continue reading }

art { Douglas Huebler, Variable Piece #44 / Global, 1971 | more }

In a mossy forest in the western Andes of Ecuador, a small, cocoa-brown bird with a red crown sings from a slim perch. […] Three rival birds call back in rapid response. […] They are singing with their wings, and their potential mates seem to find the sound very alluring. […]

This is an evolutionary innovation — a whole new way to sing. But the evolutionary mechanism behind this novelty is not adaptation by natural selection, in which only those who survive pass on their genes, allowing the species to become better adapted to its environment over time. Rather, it is sexual selection by mate choice, in which individuals pass on their genes only if they’re chosen as mates. From the peacock’s tail to the haunting melodies of the wood thrush, mate choice is responsible for much of the beauty in the natural world.

Most biologists believe that these mechanisms always work in concert — that sex appeal is the sign of an objectively better mate, one with better genes or in better condition. But the wing songs of the club-winged manakin provide new insights that contradict this conventional wisdom. Instead of ensuring that organisms are on an inexorable path to self-improvement, mate choice can drive a species into what I call maladaptive decadence — a decline in survival and fecundity of the entire species. It may even lead to extinction.

{ NYT | Continue reading }

art { Cy Twombly, Achilles Mourning the Death of Patroclus, 1962 }

Simulation suggests 68 percent of the universe may not actually exist

According to the Lambda Cold Dark Matter (Lambda-CDM) model, which is the current accepted standard for how the universe began and evolved, the ordinary matter we encounter every day only makes up around five percent of the universe’s density, with dark matter comprising 27 percent, and the remaining 68 percent made up of dark energy, a so-far theoretical force driving the expansion of the universe. But a new study has questioned whether dark energy exists at all, citing computer simulations that found that by accounting for the changing structure of the cosmos, the gap in the theory, which dark energy was proposed to fill, vanishes.

{ New Atlas | Continue reading }

art { Portia Munson, Her Coffin, 2016 }

As men are generally more short-term oriented in their sexuality than women, and given that cigarette and alcohol use are still considered masculine behaviors, we explored if female smoking and drinking can function as a short-term mating strategy. […]

The experiment showed that young men perceive women who use cigarettes and alcohol as being more sexually unrestricted. Furthermore, tobacco and (especially) alcohol use brought some short-term attractiveness benefits to women. In short-term mating contexts, drinking enhanced women’s attractiveness, whereas occasional smoking was found equally desirable as not smoking. However, in long-term mating contexts, frequent drinking and all smoking behavior harmed women’s desirability.

{ Evolutionary Psychology | Continue reading }

art { Edvard Munch, Girls on the Bridge, 1902 }