Eyelashes have evolved as a protective feature for the eyes, offering defense against external dangers such as contamination, excessive evaporation, and shear stress from airflow. They may also serve as indicators of an individual’s health, since various diseases, both congenital and non-congenital, can influence eyelash length. […]

this research primarily focused on the attractiveness of eyelash length […] investigating perceptions of health and sexual receptivity as functions of eyelash length, hypothesizing that while long eyelashes may be rated as less attractive, they could be perceived as signals of sexual receptivity. […]

results showed that eyelash length is positively associated with perceived sexual receptivity, suggesting that longer eyelashes might signal openness to casual relationships, despite lower attractiveness and health ratings at lengths beyond the optimal one-third ratio

{ Archives of Sexual Behavior | Continue reading }

{ Focus. The stairs will change direction every ~10 seconds. }

Eye Contact Marks The Rise And Fall of Shared Attention in Conversation

Conversation is the platform where minds meet —the venue where information is shared, ideas co-created, cultural norms shaped, and social bonds forged. Its frequency and ease belie its complexity.

Every conversation weaves a unique shared narrative from the contributions of independent minds, requiring partners to flexibly move into and out of alignment as needed for conversation to both cohere and evolve. How two minds achieve this coordination is poorly understood.

Here we test whether eye contact, a common feature of conversation, predicts this coordination by measuring dyadic pupillary synchrony (a corollary of shared attention) during natural conversation.

We find that eye contact is positively correlated with synchrony as well as ratings of engagement by conversation partners.

However, rather than elicit synchrony, eye contact commences as synchrony peaks and predicts its immediate and subsequent decline until eye contact breaks. This relationship suggests that eye contact signals when shared attention is high.

Further, we speculate that eye contact may play a corrective role in disrupting shared attention (reducing synchrony) as needed to facilitate independent contributions to conversation.

{ PsyArXiv | Continue reading }

photo { Edward Weston, Flora Chandler Weston, 1909 }

Between the 1970s and the early aughts, the incidence of myopia in the US nearly doubled, to 42 percent. Myopia’s rise has been the starkest in Asia; one survey in Korea found a rate as high as 96 percent among teenagers.

Clearly, something is going on. But scientists can’t agree on exactly what. Being constantly tethered to devices and books indoors might be part of it: Based on a handful of large epidemiological studies on myopia, spending time outdoors—especially in early childhood—reduces the onset of myopia. […]

Neuroscientists discovered the classic animal model for myopia by accident in the 1970s, when they were sewing one eye shut in newborn monkeys to study the development of the brain’s visual system. […] Around the same time as the eye-sewing experiments, neuroscientists figured out they could do the same in chickens and tree shrews—much easier to keep in the lab than monkeys. And instead of sewing the eyelid shut, they could just put what looks like half a ping pong ball over the eye. This “form deprivation” model of myopia has inspired some fascinating science. In 2010, for example, Morgan’s collaborators found that exposure to bright light could reverse this type of induced myopia in chickens. Further experiments pinned down the mechanism, too: Light activates the neurotransmitter dopamine, which prevents the eyes from growing longer.

{ Wired | Continue reading }

When he was two years old, Ben stopped seeing out of his left eye. His mother took him to the doctor and soon discovered he had retinal cancer in both eyes. After chemotherapy and radiation failed, surgeons removed both his eyes. For Ben, vision was gone forever.

But by the time he was seven years old, he had devised a technique for decoding the world around him: he clicked with his mouth and listened for the returning echoes. This method enabled Ben to determine the locations of open doorways, people, parked cars, garbage cans, and so on. He was echolocating: bouncing his sound waves off objects in the environment and catching the reflections to build a mental model of his surroundings.

Echolocation may sound like an improbable feat for a human, but thousands of blind people have perfected this skill, just like Ben did. The phenomenon has been written about since at least the 1940s, when the word “echolocation” was first coined in a Science article titled “Echolocation by Blind Men, Bats, and Radar.” […]

Neuroscience used to think that different parts of the brain were predetermined to perform specific functions. But more recent discoveries have upended the old paradigm. One part of the brain may initially be assigned a specific task; for instance, the back of our brain is called the “visual cortex” because it usually handles sight. But that territory can be reassigned to a different task. There is nothing special about neurons in the visual cortex: they are simply neurons that happen to be involved in processing shapes or colors in people who have functioning eyes. But in the sightless, these same neurons can rewire themselves to process other types of information. […]

we refer to the brain’s plasticity as “livewiring” to spotlight how this vast system of 86 billion neurons and 0.2 quadrillion connections rewires itself every moment of your life. […]

In Ben’s case, his brain’s flexible wiring repurposed his visual cortex for processing sound. As a result, Ben had more neurons available to deal with auditory information, and this increased processing power allowed Ben to interpret soundwaves in shocking detail. Ben’s super-hearing demonstrates a more general rule: the more brain territory a particular sense has, the better it performs. […]

Recent decades have yielded several revelations about livewiring, but perhaps the biggest surprise is its rapidity. Brain circuits reorganize not only in the newly blind, but also in the sighted who have temporary blindness. In one study, sighted participants intensively learned how to read Braille. Half the participants were blindfolded throughout the experience. At the end of the five days, the participants who wore blindfolds could distinguish subtle differences between Braille characters much better than the participants who didn’t wear blindfolds. Even more remarkably, the blindfolded participants showed activation in visual brain regions in response to touch and sound. When activity in the visual cortex was temporarily disrupted, the Braille-reading advantage of the blindfolded participants went away. In other words, the blindfolded participants performed better on the touch- related task because their visual cortex had been recruited to help. After the blindfold was removed, the visual cortex returned to normal within a day, no longer responding to touch and sound.

But such changes don’t have to take five days; that just happened to be when the measurement took place. When blindfolded participants are continuously measured, touch-related activity shows up in the visual cortex in about an hour. […]

In the ceaseless competition for brain territory, the visual system has a unique problem: due to the planet’s rotation, all animals are cast into darkness for an average of 12 out of every 24 hours. (Of course, this refers to the vast majority of evolutionary time, not to our present electrified world.) Our ancestors effectively were unwitting participants in the blindfold experiment, every night of their entire lives.

So how did the visual cortex of our ancestors’ brains defend its territory, in the absence of input from the eyes?

We suggest that the brain preserves the territory of the visual cortex by keeping it active at night. In our “defensive activation theory,” dream sleep exists to keep neurons in the visual cortex active, thereby combating a takeover by the neighboring senses. […]

In humans, sleep is punctuated by rapid eye movement (REM) sleep every 90 minutes. This is when most dreaming occurs. (Although some forms of dreaming can occur during non-REM sleep, such dreams are abstract and lack the visual vividness of REM dreams.)

REM sleep is triggered by a specialized set of neurons that pump activity straight into the brain’s visual cortex, causing us to experience vision even though our eyes are closed.

{ Time | Continue reading }

image { Michael Mann, Manhunter, 1986 }

quote { Does the popular quote, “No artist tolerates reality,” belong to Nietzsche? }

Faces provide not only cues to an individual’s identity, age, gender, and ethnicity but also insight into their mental states. The aim was to investigate the temporal aspects of processing of facial expressions of complex mental states for very short presentation times ranging from 12.5 to 100 ms. […]

Results show that participants are able to recognise very subtle differences between facial expressions; performance is better than chance, even for the shortest presentation time. Importantly, we show for the first time that observers can recognise these expressions based on information contained in the eye region only.

{ i-Perception | Continue reading }

We showcase an optical phenomenon that we call Third-Eye Rivalry. The effect is most easily induced by viewing one’s own reflection in a mirror. Using the pupil of the opposing eye as a fixation target, people can easily cross their eyes in free fusion to experience vivid rivalry. The resulting percept is of a prominent central “third” eye and two peripheral faces rivaling for perceptual dominance.

{ i-Perception | Continue reading }

{ sunglasses-like VR hardware }

If you wear designer glasses, there’s a very good chance you’re wearing Luxottica frames.

The company’s owned and licensed brands include Armani, Brooks Brothers, Burberry, Chanel, Coach, DKNY, Dolce & Gabbana, Michael Kors, Oakley, Oliver Peoples, Persol, Polo Ralph Lauren, Ray-Ban, Tiffany, Valentino, Vogue and Versace.

Along with LensCrafters, Luxottica also runs Pearle Vision, Sears Optical, Sunglass Hut and Target Optical, as well as the insurer EyeMed Vision Care.

And Italy’s Luxottica now casts an even longer shadow over the eyewear industry after merging last fall with France’s Essilor, the world’s leading maker of prescription eyeglass lenses and contact lenses. The combined entity is called EssilorLuxottica. […]

“You can get amazingly good frames, with a Warby Parker level of quality, for $4 to $8,” Butler said. “For $15, you can get designer-quality frames, like what you’d get from Prada.”

And lenses? “You can buy absolutely first-quality lenses for $1.25 apiece,” Butler said.

Yet those same frames and lenses might sell in the United States for $800.

{ Los Angeles Times | Continue reading }

photo { Jeff Wall, Parent child, 2018 }

Faces are a primary source of social information, but little is known about the sequence of neural processing of personally relevant faces, such as those of our loved ones.

We applied representational similarity analyses to EEG-fMRI measurement of neural responses to faces of personal relevance to participants – their romantic partner and a friend – compared to a stranger. Faces expressed fear, happiness or no emotion. […]

Models of face processing postulate that recognition of face identity takes place with structural encoding in the fusiform gyrus around 170 ms after stimulus onset. We provide evidence that the high personal relevance of our friends’ and loved ones’ faces is detected prior to structural encoding […] as early as 100 ms after stimulus onset. […] Our findings imply that our brain can ‘bypass’ full structural encoding of face identity in order to prioritise the processing of faces most relevant to us.

{ BioRxiv | Continue reading }

acrylic on canvas { Nychos, Barbie Meltdown, 2016 }

Where Does Time Go When You Blink?

Retinal input is frequently lost because of eye blinks, yet humans rarely notice these gaps in visual input. […]

Here, we investigated whether the subjective sense of time is altered by spontaneous blinks. […]

The results point to a link between spontaneous blinks, previously demonstrated to induce activity suppression in the visual cortex, and a compression of subjective time.

{ bioRxiv | Continue reading }

photo { Helmut Newton, A cure for a black eye, Jerry Hall, 1974 }

We have scientifically studied magic tricks to explore the human mind. For example, we use cutting-edge eye-tracking technologies to investigate how magicians misdirect our attention, and this work informs us about why people fail to see things right in front of their eyes. […] Magic works because we are typically unaware of our mind’s limitations, and most magic techniques rely on exploiting these surprising cognitive biases and limitations. Magicians don’t simply manipulate what you perceive – they manipulate your false beliefs about how much you can perceive.

{ The Psychologist | Continue reading }

related { we report a series of studies investigating the “paranormal potential” of magic performances }

The new “eyes wide shut” illusion uses a standard enlarging (shaving or makeup) mirror. Close one eye and look at the closed eye in the mirror; the eye should take up most of the mirror. Switch eyes to see the other closed eye. Switch back-and-forth a few times, then open both eyes. You see an open eye. Which eye is it? To find out, close one eye. Whichever you close, that’s the eye you see. How can this be possible? The brain is fusing two images of the two eyes.

{ Perception | Continue reading | Thanks Brad! }

However, no one has hitherto laid down the limits to the powers of the body, that is, no one has as yet been taught by experience what the body can accomplish solely by the laws of nature, in so far as she is regarded as extension. No one hitherto has gained such an accurate knowledge of the bodily mechanism, that he can explain all its functions; nor need I call attention to the fact that many actions are observed in the lower animals, which far transcend human sagacity, and that somnambulists do many things in their sleep, which they would not venture to do when awake: these instances are enough to show, that the body can by the sole laws of its nature do many things which the mind wonders at.

Again, no one knows how or by what means the mind moves the body, nor how many various degrees of motion it can impart to the body, nor how quickly it can move it.

{ Spinoza, Ethics, III, Proposition II, Scholium | Continue reading }

unrelated { eye colour may not be a priority when choosing a partner }

Across four experiments participants chose between two versions of a stimulus which either had an attractive left side or an attractive right side. […]

In each experiment participants showed a significant bias to choose the stimulus with an attractive left side more than the stimulus with an attractive right side. The leftward bias emerged at age 10/11, was not caused by a systematic asymmetry in the perception of colourfulness or complexity, and was stronger when the difference in attractiveness between the left and right sides was larger.

The results are relevant to the aesthetics of product and packaging design and show that leftward biases extend to the perceptual judgement of everyday items. Possible causes of the leftward bias for attractiveness judgements are discussed and it is suggested that the size of the bias may not be a measure of the degree of hemispheric specialization.

{ Laterality | Continue reading }

art { Adrian Piper, Catalysis III, 1970 }

The image of the world that we see is continuously deformed and fragmented by foreshortenings, partial overlapping, and so on, and must be constantly reassembled and interpreted; otherwise, it could change so much that we would hardly recognize it. Since pleasure has been found to be involved in visual and cognitive information processing, the possibility is considered that anhedonia (the reduction of the ability to feel pleasure) might interfere with the correct reconstruction and interpretation of the image of the environment and alter its appearance.

{ Schizophrenia Research and Treatment | 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 }

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 2012, a genetic analysis confirmed that Concetta’s enhanced color vision can be explained by a genetic quirk that causes her eyes to produce four types of cone cells, instead of the regular three which underpin colour vision in most humans. […]

Women with four cone types in their retinas are actually more common than we think. Researchers estimate that they represent as much as 12% of the female population. […] A woman has the potential to produce four cone types because she inherits two X-chromosomes. […]

The three cone types that most of us have in our retinas allow us to see millions of colours. Each cone’s membrane is packed with molecules, called opsins, which absorb lights of some wavelengths and cause the cone to send electrical signals to the brain. […]

Four cones don’t automatically grant you superior color vision. […] Only one of the seven women with four cones behaved as if she actually perceived differences between the colour mixtures that were invisible to everyone apart from her sons.

{ The Neurosphere | Continue reading }

Criminal investigations often use photographic evidence to identify suspects. Here we combined robust face perception and high-resolution photography to mine face photographs for hidden information. By zooming in on high-resolution face photographs, we were able to recover images of unseen bystanders from reflections in the subjects’ eyes.

To establish whether these bystanders could be identified from the reflection images, we presented them as stimuli in a face matching task (Experiment 1). Accuracy in the face matching task was well above chance (50%), despite the unpromising source of the stimuli. […] In a test of spontaneous recognition (Experiment 2), observers could reliably name a familiar face from an eye reflection image.

For crimes in which the victims are photographed (e.g., hostage taking, child sex abuse), reflections in the eyes of the photographic subject could help to identify perpetrators.

{ PLOS | Continue reading }