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If I think of a checkerboard, is there a similar structure to see in my visual cortex?

Probably. What you mentioned in your question is called retinotopy. There is a mapping between locations on your retina and areas on your cortex. As you go further up the visual processing streams, ...
K A's user avatar
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9 votes
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If the optic nerve transmits to both hemispheres, how do split-brain experiments work?

Some of those pop science articles might be simplifying a bit by saying the stimuli are provided to the left or right eyes. In fact, they are actually presented to the left or right visual field which ...
Bryan Krause's user avatar
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7 votes
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Why is it easier to see black text on a white background?

The short answer is that it is not necessarily easier to read black on white. Contrast is more important in lightness and colour, it just so happens that black and white is the highest contrast. So ...
Comte's user avatar
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7 votes

If the color black reflects no light, how are we able to see it?

Objects are visually perceived when they reflect light. A black object does not reflect any light. In other words, no photons are reflected to be detected by the photoreceptors in the retina. A black ...
AliceD's user avatar
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Do cats exhibit the bouba/kiki effect?

The bouba/kiki effect is the phenomenon that about 95% of subjects assign the name bouba to a blobby form, and the name kiki to a pointy shape (Fig. 1). Fig. 1. Kiki and bouba, at least in 95% of the ...
AliceD's user avatar
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7 votes
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How to use a QUEST staircase in 2-AFC?

There is a lot going on in your question. QUEST, as well as many other adaptive procedures, is well suited for a task like estimating morph distance in a 2-AFC paradigm. There are, however, a couple ...
StrongBad's user avatar
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6 votes

How does the brain structure 3D visual data?

This question cannot be answered in the form in which you asked it both because of the limits of current neuroscientific theories and methodologies when it comes to determining the structures of ...
Larry Muhlstein's user avatar
6 votes

Are we able to simulate pain through the brain?

Short Answer It appears that stimulation of the thalamus would invoke feeling of pain: Direct deep brain stimulation (DBS) in the VP thalamus from patients without pain typically evoked nonpainful,...
Chris Rogers's user avatar
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6 votes
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When your two eyes disagree sharply

Binocular rivalry refers to a situation where you present different images to each eye (often in the context of an experiment, although you also point out some quick 'at home' ways to achieve this), ...
Bryan Krause's user avatar
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6 votes
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Why is the occipital lobe behind instead of in front?

From the retina, visual signals next travel through the lateral geniculate nucleus of the thalamus. This nucleus is quite centrally located, about as much in the middle of the brain as possible, and ...
Bryan Krause's user avatar
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6 votes
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What degree of control do we have on eye movements?

Short answer We have a lot of control over our eye movements, including saccades. We can suppress saccades and make an anti-saccade instead. So can monkeys, our close cousins. Children have a lot more ...
AliceD's user avatar
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5 votes

Do direct cortical pathways exist in the visual system, or do they all go via the thalamus?

Short answer Intracortical projections can be routed directly to other cortical areas (cortico-cortical projections), or via the thalamus (cortico-thalamo-cortical projections). Background ...
AliceD's user avatar
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5 votes

What is the optimal contrast ratio for best readability?

Short answer Higher contrast increases readability. Background In a series of papers under the umbrella "Psychophysics of Reading" (link is to first paper in the series of five) the authors ...
AliceD's user avatar
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5 votes
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What do you call sensations without stimuli?

Short answer Visual hallucinations and, more specifically, phosphenes are the terms you are probably after. Background I'll basically provide a list of terminologies below, as your question seems to ...
AliceD's user avatar
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5 votes
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How does a person who wears prism glasses through which the world is perceived upside-down experience the transition back to normal?

Short answer Based on the papers I've found I conclude that visual perceptions are not grossly altered after wearing prism glasses for extended periods. Instead, adaptation to prism glasses is mainly ...
AliceD's user avatar
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5 votes
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What happens in my retina if I press on my eyeballs?

Short answer Pressure phosphenes are believed to be induced by sensory neurons in the retina downstream from the photoreceptors due to stretch-mediated activation. Background You are referring to ...
AliceD's user avatar
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5 votes
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Is V1 involved in visual imagery?

Short answer V1 can be recruited for visual imagery, but it is not strictly needed for imagery to occur, and it is not sufficient in itself to allow for visual imagery. Background Visual imagery is a ...
AliceD's user avatar
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4 votes

What is the source for the W3C's Contrast Ratio formula?

The W3C link provided by Mark in a comment on "Understanding WCAG 2.0" provides the source for the contrast ratio formula under the "Notes on formula" section. The formula (L1/L2) ...
Steven Jeuris's user avatar
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4 votes
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How long does it take to learn to cane travel?

Short answer Generally, a few months of active, guided training. Background Based on an article from a guide cane instructor who is a cane traveler himself, I can answer the question as follows: ...
AliceD's user avatar
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4 votes

How do mammals estimate the speed of moving objects?

@AliceD gave a great answer on the bottom up pathway. Let me add some top-down processing bits into the picture, since that's what you are asking. First of all, at a perceptual level, motion ...
Memming's user avatar
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4 votes
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Do we perceive contrast colour patterns easily because of adaptation?

Short answer Contrast is hardwired in the visual system and can be explained by retinal and brain connectivities without the need for adaptive processes. My answer pertains to adaptation at the ...
AliceD's user avatar
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4 votes

Is prior experience necessary to perceive the Kanizsa triangle illusion?

It's a difficult question to answer. My educated guess is that the appearance of the triangle, and illusionary contours in general, would persist, even in individuals who have never seen a triangle ...
AliceD's user avatar
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4 votes

How to use a QUEST staircase in 2-AFC?

Start here: Adaptive Psychophysical Procedures (Treutwein, 1995) [PDF] If you want to get fancy, I suggest a more contemporary approach for the staircase called accelerated stochastic approximation. ...
noumenal's user avatar
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4 votes

How to use a QUEST staircase in 2-AFC?

There are numerous studies that reveal contradictory data about face-to-face in autism. Continues the research paradigm that contrasts faces and objects. https://www.ncbi.nlm.nih.gov/pmc/articles/...
hexadecimal's user avatar
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4 votes
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Learning In Retina

It is not immutable. There are many studies on retinal plasticity, for example using laser coagulation and showing that after selective lesions new connections can be formed even in the adult retina, ...
matteo's user avatar
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4 votes

The interactions between hallucinations and reality in people with schizophrenia

Unfortunately hallucinations of visual type seldom occur with schizophrenia. When visual hallucinations occur in schizophrenia or more frequently (but still uncommon) in other disorders they are ...
r0berts's user avatar
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4 votes
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The interactions between hallucinations and reality in people with schizophrenia

Short answer Visual hallucinations in psychotic disorders like schizophrenia are typically not simple transformations of an inanimate lifeless object into another state. They are not a car turning ...
AliceD's user avatar
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4 votes
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Is there a word that differentiate between image rotation and image translation?

I believe you are talking about recognition part that say if the image is transformed to be flipped one is able to righaway recognize the object, however if the transformation is say 90 degrees then ...
user0193's user avatar
  • 202
3 votes

What is the maximum time difference to still associate an acoustic and visual event?

Short answer In the case of simple stimuli, visual and auditory stimuli can be offset between 25 and 50 ms and still be perceived as coming from one and the same same event. Background The question ...
AliceD's user avatar
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