How does fatigue affect comparisons?

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How does fatigue affect latent print comparisons? To answer this question, we collected eye tracking data from 5 examiners when they were either fresh or tired. We found a number of interesting results, including:

Examiners suffer from ‘decision fatigue’, where they are more likely to reach an inconclusive decision when they are tired.

When examiners are tired, their search is less efficient and less organized.

Fatigue seems to reduce the capacity of visual working memory. Rather than putting whole target groups in memory, examiners only put one or two features in memory to compare.

In addition, adaptation is a physiological process that may prevent examiners from extracting faint ridge details when they are tired. To guard against this, keep a printout of the faintest print you can still pull ridge detail out of. If you think you are tired, try looking at it at different orientations (to disrupt memory). If you can’t see details you can normally see, work on paperwork for a while or take a break to let your visual system recover.

For the full report, download the pdf