31 Days: Apocalypse, Now ~ Day 15 :: Vision is Controlled Hallucination

metalorbburiedfernKCCExtNLNH29Sept2018Welcome to day 15 of 31 Days of Apocalypse, Now, a month of posts about apocalypse, revelation, uncovering what’s been hidden. Each post will look at these ideas from its own vantage point, which may not obviously connect with the others, and which may only peripherally seem related. I won’t attempt to tie the posts together. They’ll all be listed here, as they are posted.


You know that famous optical illusion that either shows an old woman looking to her left or a young woman looking over her right shoulder? This:

It’s called: “My Wife and My Mother-In-Law,” created by cartoonist William Ely Hill and published in Puck magazine in 1915.

Usually, you see it one way or the other, and it’s hard to switch, until you finally do see it the other way and then you can move back and forth between the two ways of seeing it fairly easily. I find it almost impossible to see the old woman in this one. I can sort of see something that’s not the young woman, but it’s more like a hand-puppet that resembles a frog’s snout.

There’s another similar illusion, a rabbit-duck (created by Joseph Jastrow, and published in 1899 in Popular Science Monthly), that I repeatedly, even on first viewing, find very easy to switch between.

Both of these illusions involve ambiguity, i.e., the drawing can be visually interpreted in two ways that are mutually exclusive. And when there is ambiguity, the human brain seeks solid ground, either averaging ambiguous information or choosing what it deems the most likely interpretation and ignoring the other alternatives: “The interesting question is then, why does our consciousness insist on reporting that we’re seeing a perfectly unambiguous [image]? … [O]ur intuition is that things must happen one way or the other” (quote from the LessWrong essay cited below). You can test for yourself by looking at various optical illusions and noticing how easily your brain fixes on one way of seeing an ambiguous image. It’s a reminder that it doesn’t take much context or many cues to fix our interpretations rigidly and wrongly.



In an extremely technical neuroscience article, “Ambiguous Figures – What Happens in the Brain When Perception Changes But Not the Stimulus” (March 2012), Jürgen Kornmeier and Michael Bach note that “[n]ormally we experience our visual world as stable and unambiguous – it seems to be as we see it. Numerous optical illusions … , however, demonstrate that the information provided via our eyes is restricted, thus incomplete and often ambiguous. Our perceptual system needs to disambiguate and interpret it in order to construct stable unambiguous percepts that allow us to successfully act in our environment.”

Similarly, Diane Rogers-Ramachandran and Vilayanur S. Ramachandran in a 2008 article in Scientific American, “Ambiguities & Perception: What uncertainty tells us about the brain,” note that “ambiguity is the rule rather than the exception in perception; it is usually resolved by other coexisting … cues that exploit built-in statistical ‘knowledge’ of the visual world. Such knowledge is wired into the neural circuitry of the visual system and deployed unconsciously to eliminate millions of false solutions.”



They offer a simple explanation for how visual stimuli are processed by our brains: “Signals from the eyeballs are initially processed in the primary visual cortex at the back of the brain and then diverge into two visual pathways: the “how” pathway in the parietal lobe of the brain and the “what” pathway, linked to memories, in the temporal lobes. The former is concerned with spatial vision and navigation — reaching out to grab something, avoiding obstacles and pits, dodging missiles, and so on, none of which requires that you identify the object in question. The temporal lobes, on the other hand, enable you to recognize what an object actually is (pig, woman, table), and this process probably benefits partially from … memory-based effects.”

In the case of optical illusions, the perceptual system can’t resolve the image effectively with the information that’s been sent from the visual cortex to the parietal and temporal lobes, at least not without practice.


The systems in our brains like to make sense of things, they seek certainty. But ambiguity is a particular kind of uncertainty, “the kind that results from having too many hypotheses available, and lacking some crucial information to distinguish the correct one among them.”

That insight is from a blog posting, “This is your brain on ambiguity” written by Morendil at the LessWrong blog, who goes on to posit that as painful for the human brain as ambiguity and wavering among choices without choosing one is, it’s actually beneficial in “instrumentally effective thinking” — i.e., it “provides ‘degrees of freedom’ which are necessary to the conceptions of plans, and their flexible execution” – in areas as diverse as math and interpersonal relationships. As to the latter, “[i]n Stumbling on Happiness Daniel Gilbert argues that ambiguity is a key component of psychological resilience. A person’s success in life is partially determined by their ability to redefine their values, sense of happiness, etc. on the fly, in answer to the difficulties they encounter. This is only possible if our interpretation of the world contains lots of ambiguity to start with.”

If you want to reveal your own responses to ambiguity, try this activity (described by Morendil in the LessWrong posting): Two people sit at a café table, “with similar (or very different) implements on each side of the table: plates, forks, knives, glasses… One person touches an item and challenges the other to ‘do this!’ Ambiguity arises … because exact mappings between the two sides may not exist, but ‘analogical’ mappings often do: your wine glass maps to my water glass, for instance. The fun starts when more than one plausible analogical mapping suggests itself. Your lone wine glass maps either to my wine glass (paired with a glass of water) or to my salt shaker (the only non-plate unpaired item on my side).” Sounds like something that would give me a headache in a very few minutes as my brain overheats.




In a 2010 Psychology Today article, Luis Manzo relates the ambiguity inherent in the Old Woman/Young Woman illusion to the sport of running, recommending the mantra “Find Your Young Lady” (for me, it’d be “Find Your Old Woman”) as a reminder “that our initial impression of a situation or what jumps out first, especially when it is negative, only provides part of the story. … In every situation, there is more than meets the eye” [or the eyes’ processing centers]. He points out that “the image itself never changes. The black and white lines and spaces are always the same. However, the meaning of the image, whether it is an ‘Old Woman’ or ‘Young Lady’ changes based on which cues you choose to attend to.” Of course, you don’t have to be a runner to benefit from this insight. By keeping a flexible mind, by becoming comfortable with this kind of uncertainty, by consciously attending to seemingly contradictory cues, we can access a range of interpretations about ambiguous situations.



Interestingly, as Rogers-Ramachandran & Ramachandran note in the aforementioned SciAm article, we may “get stuck in one interpretation” of some visual optical illusions, unable to switch to the other interpretation until we “hear, verbally, that there is an alternative interpretation. It is as if your visual system —- tapping into high-level memory —- ‘projects’ a template (for example, an old or young face) onto the fragments to facilitate their perception.”

This is in line with a Gestalt view, that the mind self-organises, that it maintains “meaningful perceptions in an apparently chaotic world,” and in terms of sensory perception, that it is disposed “to perceive patterns in the stimulus based on certain rules. These principles are organized into five categories: Proximity, Similarity, Continuity, Closure, and Connectedness” (per Wikipedia).


Once the brain has determined an interpretation, sensed a pattern and run with it, we don’t always realise that another perception or interpretation is possible; but when we’ve been told there’s an alternative, our brain leaps to find it, sorting again through what it knows — of shapes, depth, contours, colour, and other stimulus-related elements, as well as of pattern memory, past experience, real-world statistical knowledge, categories of things, hard-wired visual neural circuitry — to help us see the same image differently.


There’s a sort of surreal (and apocalyptic) aspect to our sensory processes, as described in the same SciAm article. The authors relate that they’ve both “had the experience of peering at neurons all day through a microscope and then the next day ‘hallucinating’ neurons everywhere: in trees, leaves and clouds,” and then describe Charles Bonnet syndrome, affecting people who have become blind through macular degeneration or cataracts and who can no longer “limit their hallucinations. It is almost as though we are all hallucinating all the time and what we call object perception merely involves selecting the one hallucination that best matches the current sensory input, however fragmentary. Vision, in short, is controlled hallucination.



Photos are close-ups and art projects that might disorient the viewer.


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