Critical Reasoning

Further evidence of a connection between brain physiology and psychological states has recently been uncovered in the form of a correlation between electroencephalograph patterns and characteristic moods. A study showed that participants who suffered from clinical depression exhibited less left frontal lobe activity than right, while, conversely, characteristically good-natured participants exhibited greater left lobe activity. Thus one's general disposition is a result of the activity of one's frontal lobe.

Each of the following, if true, weakens the argument EXCEPT:

A.Many drugs prescribed to combat clinical depression act by causing increased left lobe activity.
B.Excessive sleep, a typical consequence of clinical depression, is known to suppress left lobe activity.
C.Frontal lobe activity is not subject to variation the way general disposition is.
D.Earlier studies indicated that frontal lobe activity and emotive states are both caused by activity in the brain's limbic activity.
E.Social interaction of the kind not engaged in by most clinically depressed people is known to stimulate left lobe activity.

I am doing real bad on 300 GMAT CR doc Qs. The language is tough to understand and comprehend. OA later.

Is it D ?

Took 10 minutes.. definitely a letgo question for me on GMAT..

After such a long time, fixed upon D.
Wouldnt be surprised even if that is not the answer, because, the longer we do the question, more the probability of getting it wrong

BTW, what is OA?

my pick is A
clearly everyone except A WEAKENS THE CONCLUSION

hi SUMAN84,
can u send me the link of CR 300 document . thanks

IMO A as well.

C - if variation in frontal lobe activity isn't correlated with general disposition, then general disposition isn't necessarily a result of the activity of one's frontal lobe.

ansh.kumar wrote:hi SUMAN84,
can u send me the link of CR 300 document . thanks

Here you go!!

https://www.beatthegmat.com/download-gma ... 59366.html

Too Bad; took 6:56 mins;

IMO A - appears to strengthen the argument, rest all weaken

Conclusion: frontal lob-->general disposition

Each of the following, if true, weakens the argument EXCEPT:

A.Many drugs prescribed to combat clinical depression act by causing increased left lobe activity.

Depression signify lack of general disposition. Drugs-->increase left lobe-->reduce depression (ie increase general disposition). Follows the causal reasoning of argument.

Answer: A
Explanation: The author is assuming because low left lobe levels and depression are correlated, the former causes the latter. We can weaken this causal relationship by establishing that 1) Depression causes a loss of left lobe activity (b, e), 2) Some other root cause is responsible for both effects (d), or 3) the findings are simply coincidence and the relationship isn't reliable (c). A, meanwhile, indicates that depression can be fought by raising left-lobe levels, strengthening the conclusion that lobe levels control disposition.