Further evidence of a connection between brain physiology and psycholo

Looking at the question and answer choices, it does not appear to get finished within 1.3 minutes.

Information provided in first clause is not of any use.
Further evidence of a connection between brain physiology and psychological states has recently been uncovered in the form of a correlation between electrencephalograph patterns and characteristic moods.

Remaining information make some sense to solve this question.
Premise 1 :
A study showed that participants who suffered from clinical depression exhibited less left frontal lobe activity than right, (left frontal lobe vs right frontal lobe)
Premise 2:
conversely, characteristically good-natured participants exhibited greater left lobe activity. (left lobe vs right lobe)
Conclusion:
Thus one's general disposition is a result of the activity of one's frontal lobe. Conclusion is based on overall frontal lobe activity.

lobes are super-set > left frontal lobe and right frontal lobe or frontal lobes are sub-set.
Lets try to find relationship between all these lobes:

This question is bit difficult because relation between Premise 1 and 2 is not concrete it is just based on one of the many assumptions.
Thus we should use negation to validate our assumption.
In a good nurtured person author says overall left lobe activity is higher than right lobe. Thus, I can assume left frontal lobe is highly active in good natured person compared to his right frontal lobe. If I negate it and I say left frontal lobe is not highly active than Premise 1 fails. With this assumption we can relate Premise 1 and Premise 2 and set a relation between them.

Prethinking: Anything which says by improving the activity of left frontal lobe a person can become good nature-rd.

I used POE to get the answer because this question is not that straightforward to allow above mentioned analysis in less than 2 min.


(a) Many drugs prescribed to combat clinical depression act by causing increased left lobe activity. (Suspect)
(b) Excessive sleep, a typical consequence of clinical depression, is known to suppress left lobe activity. ( this option is not a strengthener, it is just describing one symptom and not telling how it affects one's disposition)
(c) Frontal lobe activity is not subject to variation the way general disposition is. ( Weakener : rejecting the relationship between disposition and Frontal lobe activity )
(d) Earlier studies indicated that frontal lobe activity and emotive states are both caused by activity in the brain's limbic system. (Out of context, Only a neurologist can help us to understand how limbic system and disposition are related)
(e) Social interaction of the kind not engaged in by most clinically depressed people is known to stimulate left lobe activity. ( In depressed people something is responsible to stimulate left lobe activity, we do not know whether it decrease or increase the activity or how disposition is related)


After 3 min of brain exercise:
(a) Many drugs prescribed to combat clinical depression act by causing increased left lobe activity. (Suspect)
Why a doctor prescribes drugs to a clinically depressed patient ? Ans : to help him or her out to improve his or her mental condition or I can say to improve his or her disposition. Thus, by improving one's left lobe activity a doctor can improve one's disposition.

Let's break down our passage.
1. There is evidence connecting physiology and pysch states (correlation)
2. study showed: depression --> less left lobe, good natured --> more left lobe
3. (therefore) activity of lobe --> general disposition

As we're explicitly asked to go over all of the answers, we'll do so (instead of thinking for ourselves first).
This is an Alternative approach.

A. Many drugs prescribed to combat clinical depression act by causing increased left lobe activity. This strengthens the claim - if drugs increase activity and we still saw a lower activity, the connection between depression and left lobe is stronger than that observed
B. Excessive sleep, a typical consequence of clinical depression, is known to suppress left lobe activity. This gives an alternative explanation for lower left lobe, so weakens the depression-->activity link
C. Frontal lobe activity is not subject to variation the way general disposition is. This directly weakens the conclusion (this is the weakest 'weakener' as the studies show there is a difference, implying that that difference is one of degree)
D. Earlier studies indicated that frontal lobe activity and emotive states are both caused by activity in the brain’s limbic activity. This gives an alternative reason causing both activity and emotion
E. Social interaction of the kind not engaged in by most clinically depressed people is known to stimulate left lobe activity. Similarly to (B), this gives an alternative explanation for lower left lobe activity

(A) is our answer.

The question can be restated as "What Strengthen's the argument"

If drugs are stimulating the frontal left lobe and still the results show lower than normal activity there, this indicates clinically depressed patients even have lower frontal left lobe activity in the absence of the drugs.

Causal/Explanation Conclusion: control activity of one's frontal lobe -> control one's general disposition

(a) Many drugs prescribed to combat clinical depression act by causing increased left lobe activity.
Combating depression requires increasing left lobe activity. OR Increase (control) left lobe -> (control) combat clinical depression.

(b) Excessive sleep, a typical consequence of clinical depression, is known to suppress left lobe activity.
Clinical depression -> excessive sleep -> reduces left lobe activity. The argument is reversed (control depression to control lobe activity), thus weakening the argument.


Interchanging the cause and effect is rarely valid in critical reasoning, especially with deductive arguments. Actually, for deductive arguments, interchanging invalidates the argument altogether. As for inductive arguments, if the cause and the effect are switched, then the conclusion is inherently weakened.

(e) Social interaction of the kind not engaged in by most clinically depressed people is known to stimulate left lobe activity.

If the conclusion is:
control activity of one's frontal lobe -> control one's general disposition
Statement E is:
No social interactions for depressed ppl -> no stimulation of left lobe activity in depressed ppl
Then,
Perhaps, left lobe activity controls disposition.

However,
If the conclusion is:
control activity of one's frontal lobe -> control one's general disposition
And, opposite statement of E is:
Social interactions for depressed ppl -> stimulates left lobe activity in depressed ppl
Then,
Do we know for sure that depressed people will no longer be depressed after stimulating the left lobe? What if after left lobe stimulation they are still depressed?
Since we're still not sure and I don't think this result can be inferred, thus, E is neutral.

Between A and E anyone want to elaborate a little bit further and get some kudos from me?

Cheers

Lets go through the arguments again: Further evidence of a connection between brain physiology and psychological states has recently been uncovered in the form of a correlation between electrencephalograph 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.

Now,

who suffered from clinical depression exhibited less left frontal lobe activity than right-->

Break It Down to: 1. Had clinical depression
2. Exhibited less lobe activity

characteristically good-natured participants exhibited greater left lobe activity
Break It Down: 1. Had Good Nature
2. Exhibited greater lobe activity

No where in each of these two premises has it been explicitly stated that which is the cause & which is the effect

Now we look at the options-
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.

As we don't know which is the cause & which the effect, both can be considered to be correct

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