Zenabi90

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ok so proximal vs distal is def a confusing topic.

they way i personally keep them separate is that the proximal stimulus is whatever is literally hitting your sensory receptor. For vision, that's light, for hearing that's pressure waves, etc.

Distal stimulus is the actual thing that the proximal stimulus originated from. So for vision, that would be the object.

Vision is the simplest way to describe it, and a nice interactive experiment to help you, and it always helps me remember because it's something you can (sort of) do in a testing environment.

Get a square piece of paper. Hold it vertically in front of you. It's clearly a square right? Here the proximal stimulus, the light reflecting off of the paper and stimulating your rods and cones, approximates a square shape. The distal stimulus is the square piece of paper. So in this case, both proximal and distal stimuli are the same.

Now, sit down on the ground and put the square piece of paper down on the floor, right in front of you, like 1 inch away, and look directly down at it. Still looks like a square right?

Now slide the square paper forward, as far away from you as you can. Here comes the challenge. Look at the paper again. Is it still a square? Your instinct is to say yes. Of course it's still a square. But are you actually seeing one?

If you can, try to see the trapezoid paper on the floor. Do you see it? Really try. The truth is, the way our vision works is that the image, the proximal stimulus of the LIGHT reflecting off the paper and acting directly on the rods and cones, is a trapezoid shape. But the distal stimulus, the OBJECT is still a square.

The point of proximal vs distal stimuli isn't to make life hard or confusing. It's to illustrate the concept of "perceptual hypothesis." The perceptual hypothesis states that your brain takes the proximal stimulus (light in the shape of a trapezoid) and interprets it in the context of other information about the environment (life experiences like squares can look like trapezoids from an angle, distance from you, already known information like the paper is square) and it uses that to form a perceptual hypothesis to guess that even though your receptors say "trapezoid" the object is really "square." Your brain is trying to reinterpret the raw data from your rods and cones into "real" information about the environment that more approximates reality. So using its perceptions hypothesis about square shapes, even you your rods and cones see a trapezoid, using contextual clues and experiences, your brain processes the raw data from the rods and cones to tell you "it's a square."
 

Zenabi90

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I hope that helps. It's a longish post, and if it's still not clear, I can try to better clarify the concepts.
 
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acetylmandarin

acetylmandarin

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ok so proximal vs distal is def a confusing topic.

they way i personally keep them separate is that the proximal stimulus is whatever is literally hitting your sensory receptor. For vision, that's light, for hearing that's pressure waves, etc.

Distal stimulus is the actual thing that the proximal stimulus originated from. So for vision, that would be the object.

Vision is the simplest way to describe it, and a nice interactive experiment to help you, and it always helps me remember because it's something you can (sort of) do in a testing environment.

Get a square piece of paper. Hold it vertically in front of you. It's clearly a square right? Here the proximal stimulus, the light reflecting off of the paper and stimulating your rods and cones, approximates a square shape. The distal stimulus is the square piece of paper. So in this case, both proximal and distal stimuli are the same.

Now, sit down on the ground and put the square piece of paper down on the floor, right in front of you, like 1 inch away, and look directly down at it. Still looks like a square right?

Now slide the square paper forward, as far away from you as you can. Here comes the challenge. Look at the paper again. Is it still a square? Your instinct is to say yes. Of course it's still a square. But are you actually seeing one?

If you can, try to see the trapezoid paper on the floor. Do you see it? Really try. The truth is, the way our vision works is that the image, the proximal stimulus of the LIGHT reflecting off the paper and acting directly on the rods and cones, is a trapezoid shape. But the distal stimulus, the OBJECT is still a square.

The point of proximal vs distal stimuli isn't to make life hard or confusing. It's to illustrate the concept of "perceptual hypothesis." The perceptual hypothesis states that your brain takes the proximal stimulus (light in the shape of a trapezoid) and interprets it in the context of other information about the environment (life experiences like squares can look like trapezoids from an angle, distance from you, already known information like the paper is square) and it uses that to form a perceptual hypothesis to guess that even though your receptors say "trapezoid" the object is really "square." Your brain is trying to reinterpret the raw data from your rods and cones into "real" information about the environment that more approximates reality. So using its perceptions hypothesis about square shapes, even you your rods and cones see a trapezoid, using contextual clues and experiences, your brain processes the raw data from the rods and cones to tell you "it's a square."
Wow, thanks! I was more making this post because I thought it was funny that the SDN and reddit post were potentially referencing eachother, and in the grand scheme of studying, everyone is referencing similar MCAT study books. The best answers and explanations seem to come from people who have a new perspective/have understood something very well, or have learned about the topic outside of the mcat study material (similar to what you have presented). Thank you though, that definitely helps, because this concept was difficult to understand.



Just to make sure I understand this concept though, what would be the perception that people ultimately have of an object that comes after the proximal stimulation of the sensory receptors? Is this just termed a "perception"?



So if you are wearing glasses that make everything you see appear distorted, and you look at a dog:
Distal stimulus--->dog
Proximal stimulus--->distorted dog
Perception--->You realize that it is actually a dog, and you know that what your eyes are seeing is, in reality, false. Thus, your perception is the brain making sense of the difference between the proximal and distal stimulus. Even though your sensory receptors are presenting information, you are intelligent enough to know that this information is being altered and thus is not true.

And is the term 'sensory stimulus' for B just the type of information that is causing a perception? This is what I found in another post, and I can't really find information online that would make that definition any clearer
 

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Zenabi90

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Just to make sure I understand this concept though, what would be the perception that people ultimately have of an object that comes after the proximal stimulation of the sensory receptors? Is this just termed a "perception"?
Yes I would term that your perception (of the distal stimulus). Remember though, your perception may not be necessarily correct. Mass media often tries to manipulate the stimuli to force a different perception.

So if you are wearing glasses that make everything you see appear distorted, and you look at a dog:
Distal stimulus--->dog
Proximal stimulus--->distorted dog
Perception--->You realize that it is actually a dog, and you know that what your eyes are seeing is, in reality, false. Thus, your perception is the brain making sense of the difference between the proximal and distal stimulus. Even though your sensory receptors are presenting information, you are intelligent enough to know that this information is being altered and thus is not true.

And is the term 'sensory stimulus' for B just the type of information that is causing a perception? This is what I found in another post, and I can't really find information online that would make that definition any clearer
I would rewrite it thusly (in italics):

So if you are wearing glasses that make everything you see appear distorted, and you look at a dog:
Distal stimulus---> normal dog (correct)
Proximal stimulus--->distorted dog (correct)
Perceptual hypothesis ---> Using context clues (you know you're wearing distorting glasses) you realize that it is not a distorted dog, and using a perceptual hypothesis to correct for the distortion, it is actually a normal dog, and you know that what your eyes are seeing (the proximal stimulus) is, in reality, false. Thus, your perception is the brain making sense of the difference between the proximal and distal stimulus via a perceptual hypothesis. Even though your sensory receptors are presenting information, you are intelligent enough to know that this information is being altered and thus is not true.

And is the term 'sensory stimulus' for B just the type of information that is causing a perception? This is what I found in another post, and I can't really find information online that would make that definition any clearer
This is a poorly written question in my opinion, in the sense that I dislike "gut reaction" answer choices that attempt to penalize guessing. If you hadn't read the passage, running short on time, you would just immediately guess B because the question leads you to B. But the passage combined with the question leads me to D.

The paragraph sounds like the opening of a perceptual hypothesis section in an Intro to Psych textbook. I dug out my old Psych 1 textbook to give you an idea of how similar it is.
"However, scientists are still one step away from understanding how these organized perceptions result in a representation of the real world. Understanding the problem requires distinguishing between two kinds of stimuli..."

or rephrasing both: Science-y people are trying to figure out how you can quickly/subconsciously go from "I literally see this" to "this is what I see."


Answer B is the generically correct answer here. Yes, a sensory stimulus is any stimulus that is registered by a sensory receptor. So for example, light is a sensory stimulus for your rods and cones, but not for the hair cells in the cochlea/Organ of Corti. However, I would only choose B if the passage went on to describe something unrelated to perceptual hypotheses, like a discussion of a person's sensory organs and perhaps signal crossing concepts like synesthesia. If instead, they allude to distal vs proximal stimulus in the subsequent paragraphs, that context should point towards answer D.

This is a case where B and D have some overlap, so you have to choose the best answer. Like I said, if the rest of Passage 4 allude to proximal vs distal via perceptual hypotheses, then I would select D. I would need strong evidence to not select D actually.

What was the correct answer here?
 
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acetylmandarin

acetylmandarin

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Yes I would term that your perception (of the distal stimulus). Remember though, your perception may not be necessarily correct. Mass media often tries to manipulate the stimuli to force a different perception.



I would rewrite it thusly (in italics):

So if you are wearing glasses that make everything you see appear distorted, and you look at a dog:
Distal stimulus---> normal dog (correct)
Proximal stimulus--->distorted dog (correct)
Perceptual hypothesis ---> Using context clues (you know you're wearing distorting glasses) you realize that it is not a distorted dog, and using a perceptual hypothesis to correct for the distortion, it is actually a normal dog, and you know that what your eyes are seeing (the proximal stimulus) is, in reality, false. Thus, your perception is the brain making sense of the difference between the proximal and distal stimulus via a perceptual hypothesis. Even though your sensory receptors are presenting information, you are intelligent enough to know that this information is being altered and thus is not true.



This is a poorly written question in my opinion, in the sense that I dislike "gut reaction" answer choices that attempt to penalize guessing. If you hadn't read the passage, running short on time, you would just immediately guess B because the question leads you to B. But the passage combined with the question leads me to D.

The paragraph sounds like the opening of a perceptual hypothesis section in an Intro to Psych textbook. I dug out my old Psych 1 textbook to give you an idea of how similar it is.
"However, scientists are still one step away from understanding how these organized perceptions result in a representation of the real world. Understanding the problem requires distinguishing between two kinds of stimuli..."

or rephrasing both: Science-y people are trying to figure out how you can quickly/subconsciously go from "I literally see this" to "this is what I see."


Answer B is the generically correct answer here. Yes, a sensory stimulus is any stimulus that is registered by a sensory receptor. So for example, light is a sensory stimulus for your rods and cones, but not for the hair cells in the cochlea/Organ of Corti. However, I would only choose B if the passage went on to describe something unrelated to perceptual hypotheses, like a discussion of a person's sensory organs and perhaps signal crossing concepts like synesthesia. If instead, they allude to distal vs proximal stimulus in the subsequent paragraphs, that context should point towards answer D.

This is a case where B and D have some overlap, so you have to choose the best answer. Like I said, if the rest of Passage 4 allude to proximal vs distal via perceptual hypotheses, then I would select D. I would need strong evidence to not select D actually.

What was the correct answer here?
Thank you. I've never heard of 'perceptual hypothesis' before, so I'm glad I now know the term to describe what I was trying to get at.

The answer was D.
The passage discusses Gestalt Principles. I think this alludes to D as an answer, since the whole idea behind these principles is how our perception is influenced by top down processing and not always 100% reflective of reality.
 

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Zenabi90

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"Perceptual hypothesis" is not a high yield term for the MCAT, but it was the context for how I developed an understanding of proximal and distal stimuli in my psych course.