When a person with temporal lobe

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Stimulus

When a person with temporal lobe epilepsy is having an epileptic seizure, part of the brain’s temporal lobe produces abnormal electrical impulses, which can often, but not always, be detected through a test called an electroencephalogram (EEG). Therefore, although a positive EEG reading—that is, evidence a reasonably reliable indicator of temporal lobe epilepsy, ⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽.

What this question is testing

Most Supported

Facts

An EEG can usually pick up the abnormal electrical impulses during a temporal lobe seizure — but not always. So if the EEG shows the impulses (positive reading) during an apparent seizure, that's good evidence the person has temporal lobe epilepsy.

Evaluate

The blank follows "although a positive reading is reliable, ______." That structure asks for the flip side — what does a negative reading mean?

Since EEG only catches the impulses "often, but not always," a negative reading doesn't conclusively prove anything. The patient could have temporal lobe epilepsy and still get a negative reading because the EEG missed it.

It's like a smoke detector that goes off most times there's smoke but sometimes misses it. If it goes off, you should believe there's smoke. If it stays silent, you can't safely conclude there's no smoke.

Goal

Pick the answer that says a negative reading does not rule out the condition.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question

21.

Of the following, which one logically completes the

Answer choices

Too Strong6% picked this
a positive reading is just as reliable an indicator of the absence of
This says a positive reading is reliable for the absence of temporal lobe epilepsy. That doesn't make sense — a positive reading indicates impulses, which point toward the condition, not away from it. Wrong direction entirely. Also fails the "although" structure.
6%
Out of Scope3% picked this
a positive reading can also indicate the presence of other forms
The stimulus only discusses temporal lobe epilepsy and how EEG handles it. It says nothing about whether the impulses (or EEG positives) might also indicate other forms of epilepsy. We can't conclude this from what's given.
3%
Unsupported1% picked this
a positive reading is more frequently an erroneous reading than is
The stimulus tells us EEG can't always detect the impulses, which means there can be false negatives. But it doesn't say anything about the relative frequency of false positives vs. false negatives — only that positives are "reasonably reliable" and detection is not guaranteed. Comparing error rates of the two reading types isn't supported.
1%
Correct87% picked this
a negative reading does not mean that temporal lobe epilepsy can
Why this is right
This is exactly what the contrast structure ("although a positive reading is reliable") sets up. Because EEG can fail to detect the abnormal impulses ("not always" detected), a negative reading can't rule out temporal lobe epilepsy — the EEG might have just missed it. Positives are evidence in favor; negatives are not strong evidence against.
Skill tested: Most Supported · how this choice captures the argument's function is the move to repeat next time.
87%
Reversal / Negation3% picked this
a negative reading is just as reliable an indicator of the presence of
This says a negative reading reliably indicates the presence of temporal lobe epilepsy. That's backwards — a negative reading means the impulses weren't detected, which is at best ambiguous (could be no condition, or a missed detection). It can't reliably indicate presence.
3%

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