Exploratorium Part II: Color from Natural Chromophores

Matrix of different natural dyes, different
mordants and different natural fibers

A rainbow of colors produced on wool yarn

Using very simple recipes to make natural dyes, like frozen blackberries (mashed, mixed with boiling water, then strained), and pre-treating the natural fiber yarns with chemical mixtures called mordants from easy to find sources (like alum and cream of tartar, common kitchen chemicals, or even just by using particular metal pots for the boiling/treating, like copper, aluminum, tin or chrome pots), we were able to create a stunning array of colors, like the purple in the picture to the left.


Dyes are typically organic compounds that contain double bonds where electrons can be delocalized, such as a benzene ring or nitro group.  When light hits these chromophores, the energy of a specific wavelength is absorbed, and the rest is reflected, resulting in our perception of a colored substance.  Dyes also have chemical groups (usually charged, like hydroxyl or carbonyl groups) that can bind to a substrate material.  These will form ionic or hydrogen bonds with a charged portion of the substrate, such as keratin in wool or cellulose in cotton.


Mordants are chemicals, usually polyvalent metal compounds like various metallic salts that help fix the dye to the fiber.  Mordants for animal fibers (like wool) are alum (aluminum potassium sulfate, AlKSO4), chrome (potassium dichromate, KCr2), copper sulfate (CuSO4), tin (Stannon's Chloride, SnCl2).  Mordants for vegetable fibers involve tannic acid (or some other source of tannin).    The metal cations from copper, aluminum or tin used as mordants have valencies of +2 or +3 to allow multiple electron donors to bond.  The mordant thus acts as a bridge between the dye molecules and the fabric fiber.  Without the mordant, the dye attaches to the protein of the fiber with hydrogen bonds that break easily.  When the fiber is first heated with the mordant, the metallic salt covalently bonds to the fiber protein and then when you add the dye, the dye also attaches to the metallic salt by a covalent bond.  These stronger covalent bonds allow more dye molecules to attach, resulting in a deeper, longer-lasting color.  The mordant used effects the color achieved with the dye (the same dye will produce different color results with different mordants).  Fastness to washing, light and perspiration totally vary depending on dye used, fiber type, and mordant used.  


Some of my favorite combinations that I did: Cu mordant+carrot-top dye->light green, Al mordant + beet dye->burnt orange, Sn mordant + onion dye->bright yellow, no mordant + indigo->deep blue, Sn mordant + blackberry dye->purple.

The basic solutions with red cabbage indicator juice.

The acids with red cabbage indicator juice.

Some indicator papers made with coffee
filters soaked in various pH sensitive
chromophores (yellow=tumeric, reddish
pink=rose petal, reddish purple=red
cabbage, bluish purple=blueberries)

Anthocyanins are pigment molecules found in vacuoles of plant cells, like red cabbage, violets, blueberries, cranberries, blackberries, concord grapes, that give them a deep red, purple or blue color depending on the pH of their surroundings (redder as environment becomes more acidic). Most store-bought pH indicators change color because of the gain/loss of a H+ which changes the wavelength at which the indicator pigment absorbs and reflects light. Anthocyanins change color because of gain/loss of a hydroxyl ion, OH-, which changes the structure and thus the absorption/reflection of light depending on the acidity of the environment. In their normal function, anthocyanins are thought to act as a 'sunscreen' for the photosynthetic cells of the plant, but absorbing blue-green and UV light (often seen in young trees, shrubs, buds). The reds of autumn leaves are anthocyanins that are synthesized when the plant begins breaking down chlorophyll. Anthocyanins also fluoresce. To extract the anthocyanin from the vacuoles of red cabbage to use as a pH indicator, blend the cut up leaves and strain the juice or just simmer the cut up cabbage in water for 5-10 minutes and strain off the rich purple liquid.  You may need to dilute the dark color of the juice.  Seen in the pictures to the left, we tested the pH of various household items (ammonia, baking soda, vinegar and lemon juice) with the cabbage juice and regular pH indicator strips.  Ammonia at a pH10.0 gave a deep emerald green when mixed with the cabbage juice.  Baking soda at a ph8.5 gave a cyan.  The control cabbage juice was purple in color and had a pH6.5.  Vinegar at a pH3.0 gave a deep red color with the cabbage juice indicator.  Lemon juice at a pH2.5 gave an intense magenta.  A beautiful range of color from the simple cabbage!

Exploratorium Part I: Color from Light

Mylar light box at the Exploratorium's "Colored Shadows" exhibit

To study the caustics of different light sources, I created a box frame out of cardboard (let's say 6" deep), tape a transparency to one side, roll up a bunch of 6" by x" tubes from mylar, where x depends on different diameter tubes you want, place them all in the box, cover other end with tracing paper and *poof* you have an amazingly simple and fun tool to play with light and explore caustic networks.  From wikipedia: "In optics, a caustic or caustic network is the envelope of light rays reflected or refracted by a curved surface or object, or the projection of that envelope of rays on another surface. The caustic is a curve or surface to which each of the light rays is tangent, defining a boundary of an envelope of rays as a curve of concentrated light. Therefore, the caustics can be the patches of light or their bright edges. These shapes often have cusp singularities."

To study interference, fill a flat container with about an inch of water, place a piece of black construction paper into the water, use cheap, clear nail polish and drip a small drop onto the water.  It will quickly disperse into a thin film on the surface of the water.  Gently lift the black paper from the water, capturing this thin film on the surface and allow to dry.  Now think about what is going on to create the 'permanent oil slick' effect from interference.


The layer of nail polish you get by water-dispersing it first, is much thinner than if you tried to paint it onto the paper. Some of the light hitting the surface passes through the top surface of the nail polish layer and reflects off the bottom surface, while some of the light reflects off the top surface.  The light waves reflecting from these two surfaces overlap, adding or subtracting to each other depending on their phase.  The colors you see are the wavelengths left over when some colors are subtracted from the white light and it depends partly on the thickness of the layer of nail polish which varies over the surface of the paper.

hand shadow on homemade phosphor paper

simple cheap supplies: paper, glow in the dark paint,
leftover disposable camera

To study phosphorescence, you need to coat some sort of substrate (I used a thick cardstock) with several layers of glow-in-the-dark paint and allow to dry.  Then take apart a disposable camera so you can access the little gear wheel inside to advance the 'film' so that you can use the flash as your light source.  Have fun capturing your shadow play.

QED called into question by new calculation of the size of a hydrogen proton

A new study throws QED theory into question.  Pohl, R. et al. The Size of the Proton. Nature 466, 213–216 (2010).

The root-mean-square charge radius, rp, has been determined with an accuracy of 2 per cent (at best) by electron–proton scattering experiments. The present most accurate value of rp (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants. This value is based mainly on precision spectroscopy of atomic hydrogen and calculations of bound-state quantum electrodynamics (QED).  However, using an exotic version of hydrogen (muonic hydrogen in which a proton is orbited by a negative muon) and pulsed laser spectroscopy to measure the muonic Lamb shift, the value of rp is 5 standard deviations off of previous value.  This implies either that the Rydberg constant has to be shifted by −110 kHz/c (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient.

Non-contact sensing technology will be future of routine monitoring in medicine and research.

When rest is important to a patient, being rigged up to a heart monitor or disrupted while they sleep and having a cold stethoscope placed on their chest isn’t ideal. To get around this problem, a team of scientists at the University of Sussex, UK have successfully developed sensors that are able to detect a heartbeat up to a meter away. RJ Prance, ST Beardsmore-Rust, P Watson, CJ Harland, H Prance. "Remote detection of human electrophysiological signals using electric potential sensors." Applied Physics Letters (2008) 93: 033906.

The Electric Potential Sensors (EPS) are the world’s first electrical sensors able to monitor heartbeats accurately whilst patients relax in their bed, or rest at home. This breakthrough device gives medical teams and health workers the chance to administer patient-friendly monitoring with minimum impact on mobility or personal space.

The wideband sensors are so sensitive they may also have the capability to detect muscle signals and eye movements, or can even be used to detect brain and nerve-fiber signals.

With financial help from the South East Health Technology Alliance (SEHTA), the research team responsible for creating EPS are also currently working with in-home smart technology company PassivSystems to determine whether there’s scope to develop an even more flexible home monitoring system.

Future uses

In theory, these sensors could be used to help elderly and frail people living independently in their homes. As well as monitoring the occupancy of a room, it would also be possible to detect and alert a medical team automatically if a patient’s heartbeat changes. The EPS monitor also doubles up as a traditional heart monitor, that can take a reading from the tip of a finger.

Speaking on the development of the Electric Potential Sensors, SEHTA CEO David Parry commented, “Remote telecare can play a crucial role in helping people to remain in their homes rather than going into sheltered accommodation, but the current Passive InfraRed sensors require movement to detect a person’s presence and cannot easily differentiate between multiple people in a room.”

The EPS monitor isn’t available commercially yet, and still has to undergo patent licensing and further clinical trials before it can be rolled out to medical establishments. However, for the scientific community and especially Dr. Helen Prance, head of the Department of Engineering and Design at the University of Sussex, the four-year project looks set to make big waves in many aspects of medical science, aviation, microchip manufacture and the automotive industry.

Speaking on the future of EPS technology, Prance commented, “It is our belief that this non-contact technology will form the basis for new imaging instruments which will impact on both research and routine monitoring in many areas of science and technology.”

Not all research can be done in a mouse model...

A protein that has the same exact amino acid sequence in mice and humans, plays an entirely novel role in human brain development, new research reports.  X. Zhang et al. "Pax6 is a human neuroectoderm cell fate determinant,"Cell Stem Cell,7: 90-100. 2010.


Su-Chun Zhang and colleagues at University of Wisconsin-Madison analyzed Pax6 expression and function in human embryonic stem cells (hESCs), human fetuses, and human induced pluripotent stem (iPS) cells.  This is one of the few papers that analyzes gene expression in human embryos, and although controversial, justifies how important this is.

Pax6 is one in a family of paired box (Pax6) transcription factors that control embryonic development in a variety of cell lineages. The best-studied of the Pax factors, Pax6 is highly conserved and important to the development of eyes, pancreas, and cerebrum across many species.  In mice, Pax6 expression is detected in later stages of neural stem cell development, when the cerebrum begins to develop. But with a lack of human models, little was known how Pax6 affects human embryonic development.  When Zhang's team silenced Pax6 in mouse ESCs, the cells still generated neural stem cells when other factors, such as Sox proteins, compensated. But when they did the same in human ESCs, no neural stem cells developed, either in a Petri dish or in vivo.


Through a series of additional experiments, the team found that Pax6 is responsible for suppressing stem cell genes, like Oct4 and Nanog, while simultaneously activating neural-specific genes. Because of these dual roles, Zhang said, it is appropriate to call Pax6 a "master switch," turning some genes on and others off. The factor is so powerful, said Zhang, that even when the researchers tried to block the development of neural cells through three different non-genetic methods, such as adding factors to guide ESCs toward a mesoderm fate, Pax6 won out. As long as the factor was being expressed, cells went on to become neurons.


Since Pax6 so strongly drives hESCs to become neural stem cells, the team is now looking to see if Pax6 can also be used to maintain an adult population of those same cells. While ESCs and iPS can be maintained in a pluripotent state, it is currently very difficult to do the same in adult somatic stem cells -- over time they begin to differentiate and lose their potential. Zhang is also interested in seeing if Pax6 can reprogram other adult cells directly into neural stem cells, skipping the iPS cell state altogether.

Multicellular life is older than we thought, by 200 million years!

Newly uncovered amorphous fossils from black shale formations of the Francevillian Basin in Gabon, Africa hint that multicellular life may have evolved more than 2 billion years ago -- some 200 million years earlier than previously expected, according to a study published last week in Nature.  A. El Albani, et al., "Large colonial organisms with coordinated growth in oxygenated environments 2.1 Gyr ago,"Nature, 466:100-4, 2010.

Sedimentologist Abderrazak El Albani of the University of Poitiers in France and his colleagues discovered more than 250 specimens at the site, all dating to approximately 2.1 billion years ago, and ranging up to 12 centimeters in length. Chemical analyses confirmed the biological origin of the fossils, which are now composed of the iron-sulfide mineral pyrite that replaced the organic tissue as the organism decomposed. Interestingly, these fossils appear just a couple million years after the Great Oxidation Event, when oxygen became more widely available in the atmosphere and in the shallow oceans. This may have facilitated the evolution of a thicker organism (cells in the middle have greater difficulty obtaining oxygen if it's only at trace levels in the atmosphere). And their large and complex structures, as revealed through X-ray microtomography, are indicative of cell-to-cell signaling and coordinated growth between cells.  Specifically, the fossils display scalloped edges with radiating slits, and many have a central structure, not unlike the overall structure of a jellyfish medusa.  Unfortunately, the insides are not preserved, so it is hard to prove multicellularity, but their size, complexity and organization of structure indicate multicellularity.  Of course, there is debate on the definition of multicellularity itself, as the molecular machinery for cell-to-cell communication is found in more primitive organisms like bacterial colonies.

Unfortunately, according to one of the authors, there aren't many other fossils of that age to corroborate the connection (most of the rocks of that time have been destroyed, and the ones remaining are not pristine enough to find delicate fossil structures).  Why?  Is this due to mining?  It's a shame.  Regardless, it's important to realize that although these may be the oldest known multicellular organisms, multicellularity has evolved at least 20 times even among living lineages and thus, these are not necessarily the ancestors of all multicellular life.

Who's gonna live the longest?

Extreme longevity is associated with a select group of genetic markers, according to a new study of centenarians, people living at least 100 years. Using these markers, researchers can predict a person's ability to become a centenarian with 77 percent accuracy.


The study chose 1000 non-related Caucasian centenarians and super-centenarians (those living 110 years or longer) from the New England Centenarian Study, which has been following people since 1995. The centenarians were compared to younger Caucasians with similar genetic backgrounds.

The researchers compared the frequency of 300,000 single-nucleotide polymorphisms (SNPs) in both groups, then looked for the SNPs that appeared most unique to the centenarians. They sequentially added additional markers down the line, increasing the specificity and sensitivity of the prediction algorithm until the results plateaued. Ultimately, the algorithm contained 150 SNPs that predicted a person's chances of reaching 100 with 77 percent accuracy.

The team is developing a software program for use by other researchers, companies, and individuals to analyze a genetic sequence and determine the likelihood of extreme longevity.

Less than half of the SNPs were located in areas associated with functioning genes. Some linked to the insulin pathway, some to genes associated with Alzheimer's disease (including the ApoE4 gene variant, which is a genetic risk factor for the disease) and dementia. Many of the SNPs point to more basic biological processes, such as chromosomal instability, muscle function and control of the immune system.

Of course, the researchers could only compare centenarians to younger controls, some of whom may eventually become centenarians themselves. However, given that it is such a rare trait -- only one in six thousand people reaches 100 or older -- the researchers said this potential confounder likely had minimal impact on the findings.

The centenarians were placed into smaller groups based on their SNP profiles. Some of the groups showed special characteristics, like those who survive the longest or those with the most delayed onset of age-related diseases. There was one cluster of centenarians that did not carry many of the SNPs associated with longevity. These could be people who lived really healthy lives, or harbor rare variants linked to longevity, the authors suggested.

Even though the centenarians survived so long, the researchers found that they have similar levels of a large set of disease-associated genetic risk factors as the controls, including risk factors for Alzheimer's, diabetes, and cardiovascular disease. This seems to indicate that long-life indicators also somehow mask disease traits.
P. Sebastiani,N Solovieff, A Puca, SW. Hartley, E Melista, S Andersen, DA. Dworkis, JB. Wilk, RH. Myers, MH. Steinberg, M Montano, CT. Baldwin, TT. Perls. "Genetic signatures of exceptional longevity in humans,"ScienceExpress, July 2010.

There is an online calculator that says I will live to 94, like my maternal grandmother!  And if I worked less and gave up coffee, that would probably increase by a number of years...I really need to do 23andme and check out my SNPs.  Let me know if you hear of any future deals with them! 

Science...It works, Bitches!

It's time to finally put aside the car religious fish symbols and the darwinian fish with feet.  Recent work is elucidating one of the crucial juicy mysteries in evolutionary biology: how did fins become limbs?


Published online at Nature, a team of researchers describe 2 proteins essential to fin development in bony fishes and the loss of which may have been a key step in the evolution of tetrapods (4-legged vertebrates).  During a routine screen for genes involved in fin regeneration in the zebrafish labs of Marie-Andree Akimenko and Marc Ekker at the University of Ottawa in Canada, the team noted a remarkable pattern among two of many unknown genes revealed by the screen: a unique and specific localization along the early median fin fold, which runs along a fish's back, and in the pectoral fin buds, fins that grow on each side of the fish's body behind the gills.  This gene expression pattern suggests the proteins are structural components of actinotrichia, the thin, rigid fibrils that form the scaffold of developing bony fins.  The team named the proteins actinodin 1 and 2 (And1, And2) and noted that along with related genes from a database, and3 and and4, were entirely absent in tetrapods.


Using morpholinos (molecules that transiently silence gene expression) to knock down these genes, and1 and and2, the team discovered that the genes are partly redundant, but necessary for fin formation.  If only one of the genes was knocked down, fin development was normal.  However, if both genes were knocked down, actinotrichia didn't form and thus there was no regional recruitment of mesenchymal cells (fin bone precursors).  Other gene expression patterns important for fin patterning in the region were also extensively disrupted during the double knockdown, including those for fibroblast growth factor and sonic hedgehog.  Interestingly, the knockdown gene expression profile in the zebrafish, is highly similar to experimental chick and mouse mutants called Gli3, which results in polydactyly (the presence of numerous extra digits).  Even more noteworthy, one of the earliest aquatic tetrapods, Acanthostega, had 8 digits on each hand, which may indicate that loss of actinotrichia in ancestral tetrapods may have been conducive to limbs resembling polydactyly.


Their conclusion: "The loss of formation of actinotrichia during evolution may have induced profound changes in the morphology of the adult pectoral fins that perhaps led to short appendages without lepidotrichia and to gene expression profiles conducive to polydactyly in the earliest tetrapod species. Thus, the loss of actinotrichia may have contributed to the evolutionary transition from fin to limb."


The team's next steps are to use alternative methods of gene silencing of and1 and and2 (remember that morpholinos are only transient silencers) to see whether the fin ray will develop and what it will look like (perhaps a limb with multiple digits?!).  The team may also introduce the gene into tetrapod species and see if they can cause fins in normally limbed animals.

Dreams of Autotrophic Humans

For years I've thought about genetically modifying humans into autotrophs to solve our worries about food production, animal rights, etc. "But wait, I love food" you say. Well, two options, either we also alter the hardwiring in your brain that directly links food to hedonic pleasure and reward, such that you no longer crave food and instead seek sunshine with the same fervent, or we supplement our autotroph-abilities with minimal food, little flavor pills to satisfy our food urges if you will. In all likelihood we would not be 100% efficient in converting available light energy into food (would we all need to start (?) running around naked, to maximize skin exposure to sunlight first of all...) See a friend's calculations on the upper bound of energy production by a human-plant.   In reality, we would likely have to supplement with food anyway.  Still, if would be rad. Think Avatar in green, rather than blue.  Regardless of implausibility of suggested modifications, autotrophs rule!

Part animal-part plant, we are that much closer to making green humans that photosynthesize rather than eat. Go Autotrophs!  See the actual science paper, a Wired post, a New Scientist post.

All websites should strive for this level of creativity

A Rube Goldberg-esque website: http://producten.hema.nl/

parastychies and fibonacci phyllotaxis

Alan Turing's First Computational Biology Graphic

Alan Turing did some interesting work on morphogenesis, inspired and influenced by D'Arcy Thompson's "On Growth and Form", mentioned in an earlier post. Check out the powerpoint talk.

Dictyostelium

Like the waves in a BZ Reaction (Belousov-Zhabotinsky), a lawn of starved Dictyostelium cells is imaged using phase contrast microscopy. Cells signal via spiral waves of cAMP, and population territories form with a fruiting body in the center of each. To visualize the spirals, use has been made of the fact that when the cells experience a high concentration of cAMP surrounding them, they elongate (called polarization). When that happens the optical density of the cells changes which can be captured by the specific type of microscopy used:



A model based on physarum:

A series of experiments testing maze-solving in dictyostelium:

Thermodynamics of flows determine natural form

A 1917 book by D'Arcy Thompson, called 'On Growth and Form', disregards genetics and biochemistry, providing more of a natural philosophy in a pioneering effort to explore the mathematical principles that underlie biological form. D'Arcy studied the similarity between the shapes of a jellyfish and a drop of ink, a splash and a hydroid, between dragonfly wings and bubble froth, the growth of radiolaria and snowflakes, the spirals of nautilus and mollusk shells and sheep horns.


More recently, Adrian Bejan's Constructal theory aims to explain all biological design in nature from one thermodynamic principle. The central principle of Constructal Theory: for a finite system to persist in time (to live) it must evolve so currents can flow easier through it. This idea is used by Bejan to predict the structure of trees and other natural networks, to understand running/swimming/flying, generally to think about the design of everything that flows and moves.

Radiolaria are beautiful

Report on the Scientific Results of the Voyage of H.M.S. Challenger during the years 1873-1876, Zoology, Volume XVIII
by Ernst Haeckel, M.D., Ph. D., Professor of Zoology in the University of Jena.

Check out all the plate illustrations (and Haeckels other work), these paintings are all gorgeous and should be used in more art projects. There is also a beautiful documentary about the man and his passionate forging of art and science called Proteus.

America's Ecosystems

A new national map of the ecosystems of America could help keep healthy species from ending up endangered. Through ground and satellite surveys of land cover, the U. S. Geological Survey’s Gap Analysis Program has generated data that conservationists may be able to use to create and sustain habitat for wildlife. “These data are critical for determining the status of biodiversity, as baseline data for assessing climate change impacts, and for predicting the availability of habitat for wildlife,” said John Mosesso, the USGS manager of GAP in a press release. “Large datasets of this type are extremely important to land and wildlife managers because they allow for analysis and planning across extensive geographic areas.” The Gap Analysis Program is charged with figuring out which common species’ habitats may not be well represented by existing parks and conservation areas. The only way to do that is to mash up a bunch of data about species and land use.

In addition to the large map above, there is a searchable, zoomable mapping system available. You can download the data that underpins the visualizations, too.

LED Things I want to Make

Java-programmable LED modules for lots of fun interaction by neuroLED.

Here is a cube version:


These exploit persistence of vision (POV):

Infrared Proximity Sensor LED Interactive Table

A wind-based LED sculpture:
Firefly 870 L.E.D. Prototype Promo Video from Jason Krugman on Vimeo.

Neuroscience as Muse

Argentinian artist, Mariano Molina, is well known for paintings that bend perception and has spent the last 5 months with Argentinian neuroscientist (based in the UK) Rodrigo Quian Quiroga, developing a deep intuition about how people perceive art, especially through the use of an eyetracker. Molina says the eye tracker fascinated him because "it was like people were painting with their eyes."


The collaborators are looking for a museum or gallery interested in displaying Molina's art accompanied by explanations of the neuroscience theories the paintings illustrate. They are also applying for a grant that would allow Molina to stay as a resident artist for up to three years. Then, says Quian Quiroga, a paper might be possible. "With science, you have to be very specific and you have to aim to prove just one point," he says. "If you put the word 'art' in the title of the paper, it takes a lot more for people to take it seriously. When you mix art and science, it's not so easy to get published." But Quian Quiroga is not deterred by the bias that exists in his field. He says he has a feeling that the alliance of art and science could open a door to a new way of looking at research.


This link between art and neuroscience is also pursued by my own advisor, Shinsuke Shimojo. I attended his art gallery opening, AFTERIMAGE. This exhibit features founding members Shinsuke Shimojo, Shana Mabari, and Elizabeth Tobias and their collaborative works including installation, photography, video and sounds recordings that explore the relationship between perception, consciousness and neuroscience.


Elizabeth Tobias: Distempered

These images emerge by fusing and layering fragments of my brain signals into saturated photo panels that evoke the title of the series- distempered. Arising from my contemplation of the delicate and all too fragile balance of the mind, the traces of wave signals spill downward in broad strokes, uncontrolled yet precise, expressing the contrast between worldly and unconscious instincts. Each image was blended purposefully rendering raw thought pulsations into inimitable objects. Voltage frequencies and electrical currents are intrinsically vibrant and here they are employed within the larger context of perceptual psychology and neuroscience. The prints simultaneously engage the viewer in observing color fields while exposing my mind engaged in the same activity, creating a visual feedback loop between the audience and myself. Moreover, viewing the images for a sustained period of time modifies photoreceptors, which can induce an afterimage effect.
Dr Shinsuke Shimojo:My Own Loop

A composite of my portrait overlaying several decades of my research logs serves as a backdrop to an experimental installation introducing a Motion Induced Blindness effect. This effect indicates the brain’s sensitivity to moving/changing stimulus and quick habituation to static signals. Scrolling on top of my static portrait are brain waves (Visual and Auditory Evoked Potentials, technically speaking), recorded from my brain. The data appears to be patterns of random waves, but, in actuality, is a collective outcome of electric activity of millions of neurons, from which mental events can be decoded. Viewers are invited to fixate their gaze anywhere on the image for a sustained period to experience a rare visual event. Commonly, brain activity is responsible for perception, but here it is conversely used to suppress it. This contemplative loop also visualizes my internal process as a cognitive neuroscientist- I raise questions about the brain and use my own mind to answer. I am driven by my obsession with psychophysics, visual science, cognitive neuroscience, and sensory development. My education, research and creative inspiration is inextricably linked to my long relationship with experimental psychology within the academic and public arena. Though my projects vary, both my research and art endeavors are unanimously designed to bring to light hidden links. What I find most intriguing about (human) perceptual experience is that what is visible is the result of a hidden, invisible process utilizing physical and physiological optics, subconscious and physiological mechanisms, associations to memory, emotion and action, just to name a few. Thus in short, the brain “knows” much more than what you “see,” and as a result, you see much more than what the retina is able to process. By the same token, perception sometimes goes against conscious expectation. For this project, my long-time collaborator, artist and designer, Shana Mabari, and I created installation pieces that enable viewers to have direct experiences with perceptual effects that have driven me to scientific exploration. Though subjective responses to the work will vary, viewers, as a group, will collectively experience rare optical phenomena, which frames this project in the larger context of critical mass.
Shana Mabari:Proof (with afterimages)

Art is the interpretation of objects projected through the retina to our external reality; psychophysics is the interpretationof objects projected through the retina to our internal reality. I attempt to create one continuous interpretation in my work. Both ‘My Own Loop’ and 'Proof' are experiments within themselves exploring the relationship between creator, viewer, visual effect and experience. They are personal and universal at the same time and can only exist through an observer’s experience. My work with Dr Shinsuke Shimojo has repeatedly pushed the known boundaries of collaborative works merging creative and research fields still in development. I desire to understand our perceptual experiences by devouring the challenges shared by both the art and psychophysics communities.


Proof was my favorite. You place your face against cushioned 'goggles' and dark adapt while fixating a dimly lit central led for 30 seconds, at which point a very strong strobe is flashed through a mask with a cutout shape (snowflake like). This completely saturates your photoreceptors and you perceive an evolving, multi-colored snowflake afterimage overlaying your vision for a rather extended period of time (5-10min).

Beauty and the Brain: A Neural Approach to Aesthetics

Why do some works of art appeal so strongly to the human mind? Are artists really neuroscientists, trying to discover new and powerful ways to stimulate perceptual mechanisms in the brain? This collaboration between the Walters Art Museum and the Zanvyl Krieger Mind-Brain Institute at The Johns Hopkins University is a pioneering study in neuroesthetics, a new approach to the neural basis of the aesthetic experience.

Beauty and the Brain is both an exhibition and an experiment. Visitors will be invited to explore aesthetic spaces created by digitally morphing original works of art. Subject areas include modern abstract sculptures by renowned 20th-century artist Jean Arp. Responses from participants will be used to analyze how 3-D shape characteristics define aesthetic preference. The results will form the basis for experiments measuring aesthetic responses in the human brain with functional magnetic resonance imaging.

Art from unusual materials

Emergent art from staples, pushpins, and tape. See also this tape structure.