The Sleep-Deprived Debater
A Year 12 student, Priya, volunteers for a school debating competition held at 8:00 am on a Monday. For the four nights before, she sleeps an average of 4.5 hours per night because she is rehearsing. On the morning of the debate she reports feeling alert and confident, and her measured reaction time on a simple computer task is 12% slower than her baseline recorded two weeks earlier. Her teacher observes that she makes two factual slips during the debate that she would not normally make. Priya insists she felt fine and that the slower reaction time must be 'a computer glitch'.
1. Identify the discrepancy between Priya's subjective report and her objective performance, and explain what this pattern suggests about the reliability of self-report as a measure of alertness.
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Priya reports feeling alert and confident, yet her reaction time is 12% slower than baseline and she makes two uncharacteristic factual slips. The subjective report and the objective measures diverge.
This suggests self-report of alertness is a weak proxy for actual cognitive state. People who are sleep-deprived often lose the ability to judge their own impairment accurately - they rate themselves as functioning normally even when performance data show otherwise. So the feeling of alertness is not evidence that alertness is intact.
A judgement call follows: which measure should be trusted? The objective reaction-time data and observed errors are more directly tied to the behaviour of interest (sustained attention, working memory retrieval) than a feeling. The self-report is still useful - it tells us about her motivation and confidence - but it should not be used alone to conclude she is unimpaired.
2. Priya claims the slower reaction time is 'a computer glitch'. Evaluate this explanation using the principles of scientific reasoning, and describe one further piece of evidence that would help decide the issue.
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The glitch explanation is a post-hoc rescue of a hypothesis, not a tested claim. It is unfalsifiable as stated: any slow result can be dismissed as a glitch, so it cannot be contradicted by data. Good scientific reasoning requires that explanations be testable and that alternative explanations be ruled out, not asserted after the fact.
The claim also ignores converging evidence. The reaction-time result is not isolated - it co-occurs with two factual slips during the debate, which is a different measure (memory retrieval under pressure) pointing in the same direction. Converging evidence from independent measures strengthens the sleep-deprivation explanation.
One useful further piece of evidence: re-run the reaction-time task on the same computer under the same conditions after Priya has had two nights of normal sleep. If her reaction time returns to baseline, the glitch explanation is weakened and the sleep explanation supported. Alternatively, test the computer with another student that morning to check it is functioning normally.