For questions regarding the visual system, which serves to transduce light energy into neural impulses, or regarding visual perception, how we interpret such incoming visual information.

learn more… | top users | synonyms (1)

3
votes
0answers
17 views

Has there been a neuroscientific explanation of the color phi phenomenon?

The color phi phenomenon is a perceptual illusion in the visual domain which was demonstrated in an experiment by Kolers and von Grunau (1976). The experiment is as follows. A sequence of coloured ...
2
votes
1answer
35 views

Is there a difference between the time/effort it takes for the blind and the sighted to learn to read Braille?

The visually deprived brain undergoes extensive remodeling due to cross-modal plasticity. This leads to increased areas of the cortex being available for other purposes such as tactile processing. Now ...
2
votes
1answer
31 views

A subtle test for color-blindness

Is there a test method of proving a person being color-blind, without letting the test subject know, that he/she is being tested? E.g. showing the person cards with colored dots like depicted here is ...
2
votes
1answer
46 views

Does the brain stop processing data when the eyes move?

I was reading this question and remember back to the 70s when our local newspaper changed formats. In an article about why they made the changes that they did, one of the points they mentioned was ...
2
votes
1answer
27 views

What is the relationship between neurotransmitter release and resting potential in retinal bipolar cells?

Retinal bipolar cells are known to have resting potentials from which they can become more or less polarized. What I'm wondering is whether a bipolar cell's neurotransmitter-release rate is zero when ...
5
votes
0answers
42 views

Are some facial features more important than others in human facial recognition?

I'm often surprised by the human ability to correctly identify other individuals despite significant modifications due to ageing, hairstyle, injury etc. But, sometimes the addition of a beard and a ...
1
vote
1answer
28 views

Pupillometry: how long needs the pupil to respond towards an cognitive stimuli?

I would like to know if somebody could give me some literatur advice about the latency response of the pupil after a cognitive stimuli. I know that the light reflex response is quiet fast compared to ...
6
votes
1answer
41 views

Number of presynaptic inputs per cell in primary visual cortex

I have been digging in the literature lately, but I haven't found a nice answer with clear cut numbers (avg +- std) to this question: How many presynaptic inputs receives a pyramidal cell in primary ...
4
votes
0answers
40 views

What functions does the brain perform to recognize a familiar object unconsciously?

Let's say a person's brain experiences how a vehicle/object looks for the very 1st time. It would require lot of attention/focus/processing to analyse the object, extract features and train its neural ...
3
votes
0answers
56 views

What's the explanation of this optical illusion where many coloured arcs radiate from a central point?

I saw the image below on facebook. At first, I thought it's a GIF animation since it doesn't appear static but it turned out to be a static JPEG image and the apparent motion is caused by the brain. ...
3
votes
0answers
27 views

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

The Word Wide Web Consortium (W3C) has a formula for the contrast ratio of any two arbitrary colors, which they use to set minimum standards for text legibility: ...
5
votes
2answers
139 views

What is the minimum angle off horizontal before a line visually appears inclined at first glance?

Here is a straight line, which visually looks like a straight line: At first look (lets say minimum 2–3 sec.) the line below looks straight, but after some time you can see that it is actually an ...
4
votes
0answers
56 views

What would happen if you saw no form of light for a year?

It's proven that low levels of dopamine result in depression, anxiety, etc. And low levels of dopamine just means a lack of production or intake by the dopaminergic receptors. If the lack of happiness ...
0
votes
0answers
32 views

Does the brain reconstruct informations from modalities?

Are brains reconstructing the information that come into the modalities? For example if I see a chair, has my visual cortex built a chair and placed it where the lower layers reported the parts of ...
3
votes
0answers
26 views

Grating orientation & frequency which induces highest gamma

I am doing some research on perception and gamma activity in V1 area. To check some of my results I need to find an experimental result, from which I would know which orientations and frequencies of ...
4
votes
1answer
26 views

What study showed that humans can successfully detect objects within images once they are able to recognize those objects?

A professor in an online lecture I was watching referenced a study which he said showed that our ability as humans to detect objects within scenes (especially complex scenes) was very much connected ...
5
votes
2answers
36 views

Do we have a predisposition to view visual stimuli in a clockwise pattern?

I understand that we typically view the center of the image first and then are likely to move on a horizontal axis, but is there evidence that we tend to follow a clockwise path when viewing more ...
3
votes
1answer
72 views

Distortion of faces presented serially in peripheral vision

I've kind of already answered this question for myself, but I can't resist sharing it anyway. Please feel welcome to add anything you can in another answer. Stare at the cross in the middle and try ...
2
votes
1answer
37 views

Does transparency have its own visual channel?

Referring to (for example) Visual Thinking for Design, the book discusses various low-level processing channels in the brain. Colour and orientation are two examples. I wonder if transparency is ...
4
votes
2answers
95 views

How fast is the visual system?

I've heard that the visual system is one of our slowest sensory systems. How fast is the visual system, and how does it compare to other sensory systems (auditory, mechanosensory, pain, etc.)? For ...
5
votes
1answer
41 views

Binocular rivalry in animals?

Are there any experiments on binocular rivalry in animals? (In humans, brain responses to Rubin's vase are for example well studied.)
1
vote
2answers
57 views

Why can we not see around our point of focus of our eyes?

Why do we have to strictly focus on something to really see what it looks like? Is everything else around blurred, or is our brain trained only to see in the center of the image projected on the ...
4
votes
1answer
837 views

How does the brain read rotated text?

Suppose a human ran across a letter written at a 45 degree angle. How does the brain read this text? Most people don't often see text written at an angle, so it seems safe to assume that the brain ...
1
vote
1answer
42 views

3D Glasses Aftereffect

I am wearing a pair a 3D glasses. The left lens is red and the right lens is cyan. However, when I take them off, my left eye sees in cyan and my right eye sees in red, the complete opposite of the ...
3
votes
1answer
46 views

What is the metabolic load of the visual system?

The brain consumes energy at eight times the rate that would be predicted from mass alone (20% of total organismic load). How much of this is drawn from the visual system? How does the metabolic load ...
3
votes
0answers
54 views

Evidence for a 2-component framework of visual attention distribution

As part of my bachelor thesis on eyetracking-based gaze guidance, I've done quite a bit of reading (again) on visual attention and visual attention distribution. What caught my attention (haha) ...
3
votes
0answers
50 views

Progress on Arnheim's perceptual forces in vision

In the second edition of Rudolf Arnheim's Art and Visual Perception: A Psychology of the Creative Eye, published in 1974, the opening chapter on "balance" begins with a discussion of "perceptual ...
3
votes
1answer
53 views

How do hallucinations appear through reversing goggles?

If one is experiencing elaborated visual hallucinations, what will happen when one puts on reversing goggles? Will hallucinations change their orientations as well? Links to relevant papers will be ...
7
votes
2answers
77 views

What is the difference between spike-triggered averaging and reverse correlation?

I'm interested in the difference between spike-triggered averaging and reverse correlation. In some papers (i.e., Schwartz, Odelia, et al) I see the term 'Spike Triggered Averaging'. In others, (ie ...
9
votes
2answers
194 views

Does perception have a “frame rate”?

Are the objects of visual perception processes divisible into individual, still frames, like video is? If so: Are the perceptions from different senses synced to the same frequency? Are these ...
5
votes
2answers
74 views

Sensitivity of human eye to luminance

I heard once that the human eye has a logarithmic scale for luminance, e.g. to "feel" that a surface is three times as luminous compared to another, the former emits a light 8 times more powerful than ...
0
votes
0answers
28 views

What is the most biologically plausible model of the retina?

The retina is perhaps one of the most well-studied and well-understood parts of the brain. Are there any papers that detail full models of the retina that would mimic the firing of the ganglion cells ...
3
votes
1answer
31 views

Are representations of unattended objects “bound”?

In our phenomenal experience, different features of an object, like shape and color, seem to be "bound" together into a single percept, even though those features are represented in different parts of ...
5
votes
1answer
128 views

Computational model of biological object recognition

The human brain can achieve a remarkable ability to recognize visual patterns in an Invariant, selective and fast manner. The human visual system is quite powerful. It has an exquisite selectivity ...
2
votes
1answer
62 views

What are the visual cognitive abilities of a new born?

We know that a newborn (3 days or less) can mimic facial expressions such as tongue protrusion and head movement. This means that the child can detect faces, segment various parts of face like tongue, ...
2
votes
1answer
72 views

Is all vision based on movement?

This is something I recall from a class on human perception: vision is based on "movement" or change in what hits receptors, so if your eyes were perfectly still you couldn't see, but always-present ...
4
votes
1answer
77 views

Are we actually seeing black colored objects?

We know that black objects absorb light with almost all the frequencies of the visible spectrum. This means there will not be any frequency of light reflected and falling on our retina, in order for ...
4
votes
0answers
43 views

How is the focal point determined when looking into a clear sky?

When looking into a clear blue sky, no cloud, birds, trees or any object to give a frame of reference. When a person is actively looking, as opposed to day dreaming or gazing. The sky goes for a long ...
4
votes
3answers
457 views

Are colors real?

We know that we distinguish colors when they fall on our photo receptors in our eyes and neurons pass its signals to our brain to recognise them as the specific colors. How accurate is it? For ...
7
votes
2answers
108 views

Are there physical techniques to relieve eye strain? [closed]

I asked a question about eye strain Does looking into a mirror relieve eye strain in a similar way to looking at distant objects?. Are there any physical exercises or techniques that can help to ...
3
votes
1answer
44 views

How can I create a set of comparable symbols of different shapes?

I was thinking about doing a small experiment during university course where participants have to answer a personality quiz and then they have to compare different symbols (like triangles, rectangles ...
7
votes
1answer
51 views

What are biologically plausible ways to model binocular disparity?

I figure there is a vast body of literature on stereovision, both neurophysiological and computational studies. Computer Vision also provides some algorithmic insight on implementing binocular ...
3
votes
1answer
1k views

Why do humans' eyes enter an unfocused gaze when recalling a memory or imagining something?

The question is self-explanatory (I hope). Is this trait unique to humans? Does the direction of the unfocused gaze indicate anything about which physical part of the brain is being utilized? Is ...
1
vote
0answers
45 views

What creates the experience of “erasure” in visual perception?

When I was reading about object substitution masking, the author mentioned that sometimes we experience "erasure" of masked object. I sometimes have this kind of experience myself. It looks like the ...
4
votes
1answer
135 views

Sensory dissonance: Will the visual or auditory channel win?

Is there any research showing that our visual channel takes precedence over the auditory channel (or vice versa) if there is some dissonance between them? Examples: Say a person driving a car ...
4
votes
1answer
118 views

Why is my Gabor patch not resizing as a function of the bounding box?

I'm trying to create a Gabor patch of variable size for an upcoming experiment. Below is the python function used to generate the code. The code was ported from this tutorial for Matlab (assume ...
3
votes
1answer
416 views

Why do “cool” colors, which are actually warmer, look cool, and vice versa?

Why do cool colors look cool that are in fact warmer, and why do warm colors look warm when they are actually cooler? Blue wavelength has higher energy than red, i.e, blue flame is hotter than red ...
5
votes
0answers
77 views

How to set up a binocular rivalry experiment, that splits a single image in two separately controlled ones?

The question is about the actual physical setup and steps needed to take in order to experiment with the phenomena. I found a tutorial on jove.com, "How to Create and Use Binocular Rivalry", and it ...
5
votes
2answers
185 views

Are closed eye movements related to the content of dreams or the imagination?

During rem sleep there are observed eye movements, which seem like they would correlate with the person visualizing their dreams. Do their eye movements actually try to follow what they're dreaming ...
4
votes
1answer
187 views

Does looking into a mirror relieve eye strain in a similar way to looking at distant objects?

Sometimes when having an eye exam the eye chart is viewed through a mirror to increase the distance between the person and the chart. When using consoles, it is recommended to look away from the ...