Intuitively, intellectual skills and perceptual-motor skills seem very

Question

Intuitively, intellectual skills and perceptual-motor skills seem very different because perceptual-motor skills appear more primitive. Ontogenetically, perceptual-motor skills develop before intellectual skills, or at least before most intellectual skills are manifested. Phylogenetically, creatures "high on the evolutionary ladder" are more obviously capable of intellectual skills than are creatures "lower down ".

Perceptual-motor skills also seem more closely tied to specific forms of expression. Being a chess player does not mean one can only play with pieces of a certain size, that one can only move pieces with one's right hand, and so on. By contrast, being a violinist means one can play an instrument whose size occupies a fairly narrow range and that one must play with a rather rigid assignment of functions to effectors (bowing with the right hand, and fingering with the left). The seeming narrowness of this perceptual-motor skill expression, contrasted with the seeming openness of intellectual skill expression, seems to follow from intellectual skills having symbolic outcomes and perceptual-motor skills having non-symbolic outcomes. Symbolic outcomes need not be realized in specific ways and can rely on abstract rules. Nonsymbolic outcomes, by contrast, need more specific forms of realization and seem to depend on restricted associations between stimuli and responses.

Another difference between intellectual and perceptual-motor skills is that the two kinds of skill seem to be represented in different parts of the brain. For example, structures homologous to the optic tectum, a nucleus located on the dorsal surface of the midbrain, have a common function in all vertebrates—coordinating visual, auditory, and somatosensory information relevant to the control of orienting movements of the eyes, ears, and head. Similarities in structure and function between these and other brain areas associated with perceptual-motor behavior suggest that mechanisms for control of perceptual-motor skills are both highly specialized and conserved across species. In contrast, what distinguishes the human brain from the brains of other species—even closely related ones—is the differential growth of brain regions most strongly associated with intellectual skills, such as the association areas of the cerebral cortex.

The contention that these areas serve intellectual functions is supported by a large body of clinical and experimental literature. Together, these diverse sources of information suggest that perceptual-motor and intellectual skills depend on distinct brain circuits.    1 
 1. The passage is chiefly concerned with

A. Presenting a new theory and describing a new method to test that theory
B. Suggesting an alternative to an outdated research method
C. Demonstrating that perceptual-motor skills are closely tied to specific forms of expression
D. Arguing that two seemingly dissimilar skills are more alike than was previously assumed
E. Presenting evidence on two dissimilar skills that resolves a contradiction

2 
 2. The author mentions the game of chess in paragraph two primarily in order to

A. Present an example of an intellectual skill the mastery of which is not closely tied to specific forms of expression.
B. Present an example of an intellectual skill the mastery of which is closely tied to specific forms of expression.
C. Present an example of a skill that is both an intellectual skill and a perceptual motor skill, the mastery of which is closely tied to specific forms of expression.
D. Present an example of a perceptual-motor skill the mastery of which is not closely tied to specific forms of expression.
E. Present an example of a perceptual-motor skill the mastery of which is closely tied to specific forms of expression.

3 
 3. It can be inferred from the passage that the optic tectum

A. Functions similarly in animal and in plants
B. Functions similarly in vertebrates and invertebrates
C. Is located in a comparable area of the brains of humans and giraffes
D. Coordinates somatosensory moment in snakes
E. Has a much more sophisticated structure than the cerebral cortex

Source: GMAT 4 Full tests

Sajjad1994 · Answer

For  question #1 , I selected answer option  (E)  instead of  (D), (E)  itself did not seem a good answer but I thought it to be better than  (D) , double-checked the answer and it is indeed  (D)  but I am unable to find a strong connection of it as being the OA.

For question #3, let me try to explain.

Explanation

3. It can be inferred from the passage that the optic tectum

Difficulty Level:   Hard

Explanation

As this is a specific purpose question we can go back and re-read the related portion of the passage to strengthen our understanding of optic tectum which is discussed in the  second last paragraph:

"Another difference between intellectual and perceptual-motor skills is that the two kinds of skill seem to be represented in different parts of the brain. For example, structures homologous to the optic tectum, a nucleus located on the dorsal surface of the midbrain, have a common function in all vertebrates—coordinating visual, auditory, and somatosensory information relevant to the control of orienting movements of the eyes, ears, and head."

Now! Let's read the answer choices one by one.

A. Functions similarly in animal and in plants

This is the opposite.

B. Functions similarly in vertebrates and invertebrates

This is providing an outside idea that is not discussed in the passage.

C. Is located in a comparable area of the brains of humans and giraffes

This is correct! According to the passage, the optic tectum occupies the same area of the brain in all vertebrates (animals with a spinal column).

D. Coordinates somatosensory moment in snakes

This could or could not be true but we cannot validate this option with the help of the passage.

E. Has a much more sophisticated structure than the cerebral cortex

Same as  (B)  providing outside idea about optic tectum. Out!

Answer: C

vaishurekha · Answer

anyone explain q1 and q2??

Sajjad1994 · Answer

Official Explanation

1. The passage is chiefly concerned with

Explanation

The passage presents evidence to back the claims that intellectual skills and perceptual-motor skills are more similar than was once believed.

The best answer is D.

Question #1  is debatebale though, read my earlier reaponse  here

2. The author mentions the game of chess in paragraph two primarily in order to

Explanation

Chess is an intellectual skill the mastery of which is not closely tied to specific forms of expression. In other words, once one has learned to play the game, one can vary the way one plays, by using one’s left hand instead of one’s right, for instance.

The best answer is A.

RiyaJ0032 · Answer

can some expert explain Q1)

Isn't the whole RC about difference b/w perceptual motor skills & intellectual skills? 
1st para , though introduces the traditional belief that both are thought to be different

but the following paras just go on elaborating on this difference namely, symbolic/non symbolic outcomes, both operate in different regions of the brain

then why is the main purpose (d)

Bunuel 
 bb

Apoorva800 · Answer

KarishmaB

Can you please explain question 1? Option D doesn't make sense. The passage has throughout maintained that both skills are dissimilar without giving any hint to reduce the apparent dissimilarity.

Thank You!!

AARSHA · Answer

Sajjad1994

Hey Sajjad

Thank you for the explanation.

However, I have a doubt in Q3, why cant the correct option be D, even though the last para mentions that optic tectum has common function in all vertebrate(as snakes are vertebrate), in the following quote-

"structures homologous to the optic tectum, a nucleus located on the dorsal surface of the midbrain, have a common function in all vertebrates—coordinating visual, auditory, and somatosensory information relevant to the control of orienting movements of the eyes, ears, and head..."

Why is the correct option C, I cant find that location of Optic Tectum is the same in all vertebrae.

PietroCavallo · Answer

But the passage talks about the tectum having the same functions in all vertebrates, not being located in the same place. Hence, since a snake is a vertebrate, the tectum has the same function while we don't know wheter it's located in the same part of the brain as a giraffe. What am i missing here??

AnukaS · Answer

Why is the first answer D? The whole passage is about the contrast between the two skills. 
I chose answer E, I don't think it is 100% the accurate answer, however it does seem the closest answer when compared to the other options.

ajeeth11 · Answer

for the first questions, i am not convinced at all with option D. There is no arguing tone. Predominantly neutral and much of the paragraph stresses on the difference.

Sajjad1994 · Answer

Answer of Question #1 is debatable. Do not think much of it.

Bunuel · Answer

Archiving the question. Debatable OA.

Intuitively, intellectual skills and perceptual-motor skills seem very

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