Interesting research

Visual illusion may explain the allure of pointillist paintings



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Bridget Riley

Bridget Riley is a British painter, and one of the forerunners of the Op-Art movement.

"In my earlier paintings, I wanted the space between the picture plane and the spectator to be active. It was in that space, paradoxically, the painting 'took place,'" Bridget Riley summarized with characteristic incisive clarity. "Then, little by little, and, to some extent deliberately, I made it go the other way, opening up an interior space, as it were, so that there was a layered, shallow depth. It is important that the painting can be inhabited, so that the mind's eye, or the eye's mind, can move about it credibly."

(click images to enlarge)


Light Between, 1981-2004

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Untitled (Winged Curve), 1966

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Turquoise, Cerise, Ochre: Closed Discs with Black, 1970

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Encircling Discs with Grey in Grey to Black Sequence, 1970

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Untitled (Rothko Portfolio), 1973

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Displaced Parallels, 1962

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Twisted Curve, Horizontal Colour Movement,1977

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Untitled (Diagonal curve), 1966

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Blaze 1, 1962

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Fall, 1963

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Descending, 1965

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Cataract 3, 1967

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source source source
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It would probably be unconstitutional to not include Bridget Riley in an art + visual perception exhibition. You could talk a long time about all of the perceptual illusions her work activates. Most famously illusory motion, but many many others. While almost all of her work throughout her career has employed optical illusions, or are aesthetically inspired by them, most of her work that will be most relevant to my exhibition is from the early 60s through mid-70s.
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I need to research if there have been any fMRI scans done of people looking at her work...
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Beginnings of the curation process.

Something I need to get going on asap is the curation of what is going to be in my exhibition. I think it will a process in progress for quite a while, but gotta start somewhere. I'll be collecting loads of images to sift through that relate to each other out of a common visual perception concept/theory/phenomena/etc. Basically this will progress eventually to things that will be in the same section together within my proposed exhibition.

This first batch will probably give you a migraine if you look at them too long.

Visual perception relevancy: illusory motion
Art movement: Kinetic and Op-Art

I find it fascinating that some of these were made by "op-artists", while others were made by "vision scientists."
(click images to enlarge)

MacKay Rays
Donald M. MacKay (vision scientist)

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The Christmas Lights illusion
Gianni A. Sarcone (op-artist)

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Bridget Riley (op-artist)
(she gets her own post in a bit)

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Nick Wade (vision scientist)

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The Ouchi Illusion
Hajime Ouchi (op-artist)

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The Ouchi Illusion (variation of previous)
Akiyoshi Kitaoka (vision scientist)

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Hatpin Urchin
Akiyoshi Kitaoka (vision scientist)

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The Rotating-Tilted-Lines Illusion
Simone Gori, Kai Hamburger (vision scientists)

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The Rotating-Tilted-Lines Illusion (variation of previous)
Isia Leviant (op-artist)

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The Enigma Illusion
Isia Leviant (op-artist)

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That's it for the moment, more Bridget Riley and Akiyoshi Kitaoka pieces to come.

]link to some brief info about most of the above pieces.
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Multimodal Perception

This guy is a little goofy, but explains the concept plain and simple...

Awesome use of visual illusions to prove a point.

Transport for London 'Illusions' commercial.
Agency: M&C Saatchi
Credits: Peter Saville, Graham Fink, Mark Goodwin

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Olly Moss

uses visual illusions in poster design.



link


via the apt
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duck or rabbit?

Pretty much everyone has seen this famous illusion at some point...



Simon Cunningham takes it to a new level making a photographic version. awesome.



As fun as these illusions are though, they tell us important information about the way the brain processes visual information. They show the ability of the brain to maintain multistable perceptions. In this example there are two mutually exclusive images to be seen. The duck and the rabbit. You cannot see both the duck and the rabbit simultaneously, instead your brain shifts back and forth between the two perceptions. Other examples of ambiguous figures like this include (most famously) the Necker Cube and old-lady/young-woman illusion (not sure of proper name).



If you wanted to apply this idea to typography, this is the same phenomena that allows the middle character to be read as both '13' and 'B'...



This technique is sometimes used in logotypes. I need to look for some examples...

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The Human Visual System 101

Lovely diagrams (well 3 of the 4), that break the visual system down to its basics...

Fun!

The Whitest Boy Alive - Golden Cage

Not that the visuals are at all relevant to the music,
but it does go well with the beat and presents some fun optical illusions...



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Thanks to my friend anna for showing it to me.

See you there...

Autumn Art Lectures 2008
The Creative Brain: Conversations between Art and Science


25 November 2008
Neuroesthetics, Love and Literature
Semir Zeki and A S Byatt
(obviously going to be related to Zeki's book that comes out this week)

2 December 2008
Art Inspired by Science
Lizzie Burns and Karen Ingham

9 December 2008
In Two Minds: Neuroscience of Perception and Creativity
Mark Lythgoe and Richard Wentworth

15 December 2008
The Power of Art and Science to Understand the World
Paul Nurse and Jason Brooks
CANCELLED!

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All events take place at 6pm in the University of Bristol, Wills Memorial Building, Queen's Road, Clifton.
Open to all, no prior booking.
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Your eye is not a camera. Part 1 of ∞

If you are not convinced vision isn't always veridical (coinciding with reality),
I will have lots of visual illusions soon to change your mind.
I've been a little caught up in research (sans visuals) lately.
So now I am looking for lots of illustrations to help get back to inspiring the visual basis of all this.
They can be more than a little headache-inducing at times though, so I don't want to post tons at a time.
Here's one to get the ball rolling...

(This is a still image. Any perceived motion is an illusion.)

source


One of the most important concepts I want to stress is that our perceptions are internal constructions of hypothesized external realities!!!

(I put the 2nd half in italics because it is quoted from my notes for my Visual Perception class last semester.
It may have been a direct quote from my teacher, Adrien Mack, or it may just be me summarizing her lecture.)
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Visual Perception + Neuroscience x4

The Neural Correlates of Desire
by Hideaki Kawabata and Semir Zeki



Abstract:
In an event-related fMRI study, we scanned eighteen normal human subjects while they viewed three categories of pictures (events, objects and persons) which they classified according to desirability (desirable, indifferent or undesirable). Each category produced activity in a distinct part of the visual brain, thus reflecting its functional specialization. We used conjunction analysis to learn whether there is a brain area which is always active when a desirable picture is viewed, regardless of the category to which it belongs. The conjunction analysis of the contrast desirable > undesirable revealed activity in the superior orbito-frontal cortex. This activity bore a positive linear relationship to the declared level of desirability. The conjunction analysis of desirable > indifferent revealed activity in the mid-cingulate cortex and in the anterior cingulate cortex. In the former, activity was greater for desirable and undesirable stimuli than for stimuli classed as indifferent. Other conjunction analyses produced no significant effects. These results show that categorizing any stimulus according to its desirability activates three different brain areas: the superior orbito-frontal, the mid-cingulate, and the anterior cingulate cortices.
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The Encoding of Temporally Irregular and Regular Visual Patterns in the Human Brain
by Semir Zeki, Oliver J. Hulme, Barrie Roulston, Michael Atiyah



Abstract:
In the work reported here, we set out to study the neural systems that detect predictable temporal patterns and departures from them. We used functional magnetic resonance imaging (fMRI) to locate activity in the brains of subjects when they viewed temporally regular and irregular patterns produced by letters, numbers, colors and luminance. Activity induced by irregular sequences was located within dorsolateral prefrontal cortex, including an area that was responsive to irregular patterns regardless of the type of visual stimuli producing them. Conversely, temporally regular arrangements resulted in activity in the right frontal lobe (medial frontal gyrus), in the left orbito-frontal cortex and in the left pallidum. The results show that there is an abstractive system in the brain for detecting temporal irregularity, regardless of the source producing it.
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Seeing without Seeing? Degraded Conscious Vision in a Blindsight Patient
by Morten Overgaard, Katrin Fehl, Kim Mouridsen, Bo Bergholt, Axel Cleeremans



Abstract:
Blindsight patients, whose primary visual cortex is lesioned, exhibit preserved ability to discriminate visual stimuli presented in their “blind” field, yet report no visual awareness hereof. Blindsight is generally studied in experimental investigations of single patients, as very few patients have been given this “diagnosis”. In our single case study of patient GR, we ask whether blindsight is best described as unconscious vision, or rather as conscious, yet severely degraded vision. In experiment 1 and 2, we successfully replicate the typical findings of previous studies on blindsight. The third experiment, however, suggests that GR's ability to discriminate amongst visual stimuli does not reflect unconscious vision, but rather degraded, yet conscious vision. As our finding results from using a method for obtaining subjective reports that has not previously used in blindsight studies (but validated in studies of healthy subjects and other patients with brain injury), our results call for a reconsideration of blindsight, and, arguably also of many previous studies of unconscious perception in healthy subject
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The Golden Beauty: Brain Response to Classical and Renaissance Sculptures
by Cinzia Di Dio, Emiliano Macaluso, Giacomo Rizzolatti



Abstract:
Is there an objective, biological basis for the experience of beauty in art? Or is aesthetic experience entirely subjective? Using fMRI technique, we addressed this question by presenting viewers, naïve to art criticism, with images of masterpieces of Classical and Renaissance sculpture. Employing proportion as the independent variable, we produced two sets of stimuli: one composed of images of original sculptures; the other of a modified version of the same images. The stimuli were presented in three conditions: observation, aesthetic judgment, and proportion judgment. In the observation condition, the viewers were required to observe the images with the same mind-set as if they were in a museum. In the other two conditions they were required to give an aesthetic or proportion judgment on the same images. Two types of analyses were carried out: one which contrasted brain response to the canonical and the modified sculptures, and one which contrasted beautiful vs. ugly sculptures as judged by each volunteer. The most striking result was that the observation of original sculptures, relative to the modified ones, produced activation of the right insula as well as of some lateral and medial cortical areas (lateral occipital gyrus, precuneus and prefrontal areas). The activation of the insula was particularly strong during the observation condition. Most interestingly, when volunteers were required to give an overt aesthetic judgment, the images judged as beautiful selectively activated the right amygdala, relative to those judged as ugly. We conclude that, in observers naïve to art criticism, the sense of beauty is mediated by two non-mutually exclusive processes: one based on a joint activation of sets of cortical neurons, triggered by parameters intrinsic to the stimuli, and the insula (objective beauty); the other based on the activation of the amygdala, driven by one's own emotional experiences (subjective beauty).
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Synaesthesia

Some of the most fascinating topics within the category of 'Visual Perception and Cognition' are the so-called 'disorders'. While some of them can be incredibly debilitating, others may enhance one's perceptual experience of the world. The later is usually the case for people with synaesthesia.

Last semester I became increasingly interested with this condition of sorts, and chose it as my topic of concentration for an essay in a graduate Visual Perception and Cognition course. For anyone interested, below is my essay. As well as my list of resources, which may prove helpful for further information on this topic.

(Not sure if this was the final-final-edited-version, so please excuse any small grammatical/spelling errors)

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Synaesthesia: Current Research and Findings
Kaile Smith
Visual Perception and Cognition
Professor Dr. Arien Mack
New School University

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Abstract

Synaesthesia is a perceptual and cognitive phenomenon “in which an otherwise normal person experiences sensations in one modality when a second modality is stimulated” (E.D. Hubbard, 2005, p.509). One of the most common forms is grapheme-colour synaesthesia, in which when a synaesthete views a particular letter or number, it elicits a specific colour response. In this essay I will summarize and critique current research concentrating on grapheme-colour synaesthesia, as well as other relevant findings regarding synaesthesia in general.

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“When I see the real figure or grapheme as it is represented on whatever medium is right in front of me, or I hear it spoken, I understand it how it exists in reality, but also, a picture develops in my head of a colour and I understand it to be that colour even though I do not directly see it. From that I can remember static numbers and letters as a colour scheme, as well as a larger picture. Not only colour is associated, but also in semi-linear space like an ocean landscape and also in relation to a family structure. Especially with the numbers 1-9, and the alphabet less so. I understand them as personalities and they have a familial relationship. The number 23, is rose and green, 2 is a mom and a 3 is a pet or young baby. 19 is black and then yellow, and has a father and his oldest son relationship.”

-Rebecca O’Brien, age 22, synaesthete

Synaesthesia is a “condition in which an otherwise normal person experiences sensations in one modality when a second modality is stimulated.” Synaesthesia was first researched over one hundred years ago, and remained a popular topic of interest until halfway through the nineteenth century. Within the last ten to fifteen years there has been a revival of interest in the phenomenon due renewed interest in perceptual and cognitive processes added by advances in neurology and technology (E.D. Hubbard, 2005, p.509). While there are many variations of synaesthesia, grapheme-colour synaesthesia is believed to be the most common form, and as a result has been the most heavily studied in recent years. Topics within synaesthesia research varies from identifying processing levels, if some of synaesthetic associations are learned, the role of attention in synaesthetic experience as well as if the phenomenon is unidirectional or bidirectional.

One of the most common questions addressed in current grapheme-colour synaesthesia research is to try to “identify the level of processing involved in the formation of the subjective colours experienced by synaesthetes: are they perceptual phenomena or are they due to memory and association learning” (C. Gheri, S. Chopping, M.J. Morgan, 2008, p.841).

As a result of advances made in synaesthesia research, grapheme-colour synaesthesia is commonly broken into two major categories consisting of lower synaesthetes and higher synaesthetes, or projectors and associators, respectively, as a result of their different stages in processing. It is believed that lower synaesthetes “may have cross-wiring (or cross activation) within the fusiform gyrus.” When projector synaesthetes look at a grapheme, they see a colour projected or overlaid on the physical printed letter, number or symbol, studies have shown that the individual processes these projections as concrete perceptual phenomenon. In contrast, higher synaesthetes, “may have cross-activation in the angular gyrus” as a result of a genetic mutation casing “defective pruning of connections between brain maps,” so when associator synaesthetes look at a grapheme, they see a colour in a more conceptual manner, somewhere in their mind’s eye, or just know that the grapheme is a certain colour (V.S. Ramachandran & E.M. Hubbard, 2001, p4, E.M. Hubbard, 2005, p.509). The pruning theory is a commonly held explanation for all forms of synaesthesia as well because it has “been suggested that infants may be innately synaesthetic with sensory differentiation coming only with development and the gradual pruning of connections (or at least development of inhibition) between sensory areas” (Witthoft & Winawer, p.1).

Grossencacher and Lovelace (2001) came across another important associator synaesthetic finding. They observed “for most synaesthetes font and case have no impact on the colour.” What this argues is that if font and case did have an effect, that would mean that they synaesthetic experience was triggered by specific shape information, but because that is not the case it shows “that the representation that produces the concurrent is more abstract, concerned with the category to which the letter belongs” (Witthoft & Winawer, p.5). This is also supported by findings by Mills et al. (2002) in which a particular synaesthete, AED, was studied in depth to find many similaries between her colour associations in both English and Cyrillic letters that held similar conceptual similarities (Witthoft & Winawer, p.2).

An area of inquiry that is currently being investigated in depth, regards frequency correlates in grapheme-colour synaesthesia. Researchers have been finding important connections that shed light on what may cause certain colour associations to be more common among many grapheme-colour synaesthetes and to what extent these associations are learned. Studies by Rich et al. (2005) have shown “significant prevalences” of certain grapheme-colour associations. For example, common letters tend to be associated with common colours, i.e. in roughly forty percent of participants; A was red (Rich, 2008, p.1). Associations have also been shown to reflect the colours’ name, i.e. B is often blue or brown, and y is often yellow (G. Beeli, Mm. Esslen, L. Jancke, 2007, p.788). However, these are only approximations because each synaesthete sees a very specific hue, saturation, and lightness for each colour, which may be quite different from another synaesthete’s although both are categorized as red, for example.

Raaikmakers and Shiffrin (1992) did a test with a group of nineteen “colour-hearing” synaesthetes to prove this. “Each letter or digit was spoken aloud by the experimenter,” and all of the participants reported perceiving “the induced colour automatically and immediately after hearing the inducing letter or digital stimulus.” The participants were then asked to reproduce their synaesthetic colour via Adobe Photoshop 7.0 on a HSL scale (RGB hue, saturation, and lightness). This allowed them “to choose from 16,777,216(256^3) colours.” The participants were then asked to repeat the task 57 days later, “all of them demonstrated consistency.” The results found eighteen of the nineteen synaesthetes experiences the digit 0 as uncoloured (saturation =0). For letters, “there was a high incidence of white and yellow colours for I, j, and s (G. Beeli, Mm. Esslen, L. Jancke, 2007, p.789). The reported colours for 1 and I were highly similar in about half the subjects.” Letters and digits were also compared to “the seminal publication of Benford (1938); for letter frequency,” and “recommendations of Larch and Myers (1990);” for number frequency (G. Beeli, Mm. Esslen, L. Jancke, 2007, p.790). The test showed no relation between digit frequency and hue, although there was a slightly positive correlation between increasing digit frequency and increasing luminance. For letters there was a postitive correlation observed for letter frequency and saturation, so if a letter was more frequent, it had a higher saturation. Due to other strong evidence that synaesthesia has a genetic origin (Baron-Cohen, Burt, Smith-Laittan, Harrison, & Bolton, 1996), but is believed to be “not entirely genetically determined” (Smilek, Dixon, & Merikle, 2005) as proven through twin studies (G. Beeli, Mm. Esslen, L. Jancke, 2007, p.790), this holds consistent to Raaikmakers and Shiffrin’s results. They concluded that synaesthesia is modified by experience, i.e. increased or decrease exposure to different letters and numbers based on their frequency.

Another result of this investigation in frequency findings, was the prevalence of the digits 1 and 0, and letters i and o as commonly being associated as being colourless or white. This is believed to be a result of the characters being made up of natural shapes, a line and a circle, “that we learn to recognize before mastering the alphabet or learning to count,” thus overriding typical alpha-numerical associations (New Scientist, 2007, Vol. 196, Issue 2630). This might imply that “synaethetic linkage [takes] place very early in development, when children have typically not yet learned the digit 0 and its concept” (G. Beeli, Mm. Esslen, L. Jancke, 2007, p.791).

Another test that is commonly done to research the effects of synaesthesia, as well as identify the level of processing in which the phenomenon occurs is by using modified Stroop interference paradigms. This research has proven shown that “synaesthesia is automatic and perhaps obligatory” (Hubbard & Ramachandran, 2005, p.509). Stroop interference paradigms were tested between a group of synaesthetes, projector and associator, as well as a group of otherwise similar control subjects. Traditional Stroop paradigms were given to the controls, while modified version were given to the synaesthetes to be either purposefully congruent or incongruent to each particular synaesthete’s colour associations. For example, “for a synaesthete who sees 7 as yellow, a 7 presented in yellow would be congruent, and a 7 presented in any other colour would be incongruent.” Results showed that in the incongruent condition, for projector synaesthetes, their responses were typically much slower than in congruent conditions. In contrast, incongruent and congruent conditions did not prove to have any corollary results for associator synaesthetes in comparison to the controls taking the Stroop interference paradigms (Hubbard & Ramachandran, 2005, p.509). This reveals the differing levels of processing of synaesthesia between projector and associator synaesthetes.

These Stroop interference paradigm results have been similar to findings reported using search-related paradigms. In a study done by Hubbard and Ramachandran (2001), they “adapted a texture segregation test to subjects with displays in which one of four shapes (4-AFC) composed of a target grapheme was embedded in a background of distracter graphemes. Synaesthetes were significantly more accurate than control subjects in identifying which of the target shapes was presented.” This is congruent to a study by Palmeri et al. (2002) in which search-related tasks were given to synaesthetes in which target and distracter colours were either similar or contrasting. In cases where the target and distracters were similar, synaethete’s were much less efficient than control subjects, and more efficient than controls when the target and distracters were contrasting. These results are consistent with the idea commonly held that synaesthesia is evoked early in perceptual processing. It should be noted however that both of these tests were done with projector grapheme-colour synaesthetes, and evidence has not proven the same results for associator synaesthetes (Hubbard & Ramachandran, 2005, p510).

The question of unidirectional or bidirectional effect is also currently being explored in regards to synaesthesia, among both lowers and higher synaesthetes. Studies seem to lean towards unidirectional effect, as “an object of some sort is required to bind the synaesthetic experiences. For example, when a synaesthete views a letter, it evokes a colour, so there is a visual image that the colour is being ascribed to, be it as a projection, or in the “mind’s eye.” So far there is little evidence to show the reverse of this in which a colour evokes a number because “the number may not be able to be represented as a stimulus with physical properties of size, distance, and the like.” However, there have been arguments made for a bidirectional effect, stating, “the connections leading to synaestetic experience are of the appropriate strength or form to reach conscious awareness, whereas the connections that support bidirectional effects are not” (Hubbard & Ramachandran, 2005, p516). The exactly reasons for this difference however, is still being explored.

Yet another topic of interest among researchers is the relationship between attention and synaesthesia. Similar search-related paradigm tests by Laeng et al. (2004) have suggested, “that perceptual enhancement might occur only within the ‘functional field of attention.’” Or at least that attention is necessary for synaesthetic projections and associations to enter consciousness (Hubbard & Ramachandran, 2005, p.510).

While there have been huge strides made in the field of research relating to synaesthesia, it is often a particularly difficult field to find substantial findings and thus arguments about. One of the problems is that there remain so many varying forms and degrees of synaesthesia even within the same types. This leads to the inability to draw generalizations regarding levels of processing, innate or learned conclusions, as well as other perceptual versus cognitive arguments (Hubbard & Ramachandran, 2005, p.514). Often times studies are done with only one or a few primary subjects in which they researcher tries to make generalizations for the phenomenon of synaesthesia on a whole, and while interesting; it is hardly substantial enough to make a substantial argument. In contrast, when larger studies are done, because of the inherent variability of synaesthesia, important results are often missed as a result of trying to make generalizations based on highly variable data.

One of the most basic problems current research regarding synaesthesia is experiencing is determining an accurate estimate of the prevalence of synaesthesia within the general population. Estimates have ranged from one in twenty-five thousand, to one in twenty. One reason for large discrepancy is a result relying on most synaesthetes in samples as being self-elected participants. Also, the phenomenon on the whole is not widely known about outside the field, and many people are not even aware that they are synaesthetic. In 2006, the first random population study was done and found synaesthesia prevalence to be one in twenty-three people (J. Simner, C. Mulvenna, N. Sagiv et al., 2006, p.1024-1033). However, this has been met with much resistance claiming that its definition of synaesthesia was too broad and that it is the first study of its kind without other similar results being reported to support this argument.

Another problem that is to be considered is that while grapheme-colour synaesthesia is the most prevalent type of synaesthesia, “only 10% of synaethetes are projector synaesthetes. Past research seems to be heavily dominated by studies concentrating on the results of these projector synaesthetes, but much evidence shows that the ways in which lower synaesthetes process their experiences differs greatly from higher synaesthetes (Hubbard & Ramachandran, 2005, p.512). This fact is commonly disregarded or omitted from results.

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Resources

Baren-Cohen, S., Burt, L., Smith-Laittan, F., Harrison, J., and Bolton, P. (1996). Synaesthestia: Prevealence and familiality. Perception, 25, 1073-1079.

Beeli, G., Esslen, M., and Jancke, L. (2007). Frequency Correlates in Grapheme-Color Synesthesia. Psychological Science. Volume 18, Number 9, 788-792.

Brang, D., Edwards, L., Ramachandran, V.S., Coulson, S. (2008). Is the Sky 2? Contextual Priming in Grapheme-Color Synaesthesia. Psychological Science. Volume 15, Number 5. 421-428.

Date, M. (2008). Colour My World. Sydney Morning Herald, 10.

Galton, F. (1880). Visualised Numerals. Nature 21, 252-256.

Gheri, C., Chopping, S., Morgan, M.J. (2008) Synaesthetic Colours Do Not Camouflage Form in Visual Search. Proceedings: Biological Sciences, Volume 272, Issue 1636, 841-846.

Hubbard, E.M., and Ramachandran, V.S. (2001). Synaesthesia- A Window Into Perception, Thought and Language. Journal of Consciousess Studies, 8, Number 12, 3-34.

Hubbard, E.M., and Ramachandran, V.S. (2005). Neurocognitive
Mechanisms of Synesthesia. Neuron. Volume 48, 509-520.

Lehrer, J. (2007). Blue Monday, Green Thursday. New Scientist. Volume 194, Issue 2604, 48-51.

Simner, J.C., Mulvenna and N. Sagiv et al. (2006), Synaesthesia: The Prevelance of Atypical Cross-modal Experiences. Perception 8, 1-24-1033.

Simner, J., Ward, J. (2007). Synaesthesia, Color Terms, and Color Space. Psychological Science. Volume 19, Number 4, 412-414.

Smilek, D., Dixon, M.J., and Merikle, P.M. (2005) Synaesthesia: Discordant Male Monozygotic Twins. Neurocase, 11, 363-370.

Witthoft, N. and Winawer, J. (2003). Syesthetic Colors Determined by Having Colored Refrigerator Magnets in Childhood. Cortex, 1-9.

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As before, I have pdf's of all the above academic journal/magazine articles, email me if you are interested in reading any.
Also, the 'synaesthete' quoted at the beginning of my essay, just so happens to be my roommate back in NY, so I can put you in touch if you want to study her. ha-ha.
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Hermann Grid Illusions

link
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